Well, for you woodworkers with reasonably flat workshop floors, General has
come out with the HoverPad. It's a mobile base for heavy machine tools based
on Hovercraft technology.
I was at the Toronto Woodworking show last weekend to take part in the
premiere presentation of their new line of Access machine tools designed for
people in wheelchairs, who like to sit or who are of lower stature. While
there, I had a good look at their HoverPad. Essentially, you can push
hundreds of pounds of machine tool around with one finger. I can think of a
dozen uses for one of these. They're not much more expensive than other
decent mobile bases, can be cut to size and can be run on really low end
compressors.
So for those of you interested, here's the specs and a video.
http://www.general.ca/pagemach/machines/10824_929.html
On Mar 9, 1:48 pm, "SonomaProducts.com" <[email protected]> wrote:
> On Mar 9, 7:20 am, RicodJour <[email protected]> wrote:
> > On Mar 9, 9:47 am, "Upscale" <[email protected]> wrote:
> > > "J. Clarke" <[email protected]> wrote in message
>
> > > > Before you spend 170 bucks you might want to try
> > > >http://amasci.com/amateur/hovercft.html.
>
> > > Could be a possibility as long as one doesn't mind risking their $1000-$3000
> > > pieces of machinery on some plywood, nuts, bolts and painter's drop sheets.
> > > Of course, it's unlikely that machinery would tip over or anything, but it
> > > would definitely be a jury rig setup and subject to problems.
>
> > It's a great idea, but I have questions about what happens to the
> > exhaust air. Some of it will escape along the floor level, and
> > wherever else it exhausts, and blow sawdust everywhere. Your typical
> > less-than-exemplary-housekeeping shop would probably present
> > problems. To move the machine you'd have to do a choice cleanup, move
> > the machine, then wait for the dust to settle before you can breathe
> > in there?
>
> > The manual says to have the area around the machine clear of dust and
> > debris...how far around and how clear? You don't need a floor you can
> > eat off of with a wheeled mobile base, just clear the bigger stuff out
> > of the way, and it doesn't matter how much crud is on top of the base.
>
> Seeing that they were running it from a small air tank, I assume the
> volume of air actually escaping is pretty low. Once the physics get it
> up and floating, you just need a dribble of air to keep it there. They
> show a small amount of dust being displaced along the edge on one of
> the close-ups and you can see it is not blown but a few inches to the
> side.
Have you ever used compressed air to blow out a tool? That's only
using a small volume of air. It's the pressure which translates to
speed. Of course they're not going to show clouds of dust being blown
about in a promotional video because it would kill half of the market
on the spot. Like I said, it's a nifty idea, but it's problematic in
a working woodworking shop unless you have a shop like in one of the
Festool catalogs.
R
"PCPaul" <[email protected]> wrote in message
>
> Yes, you can get it moving at some speed by pushing it with a single
> finger for a while. *But* when you realise it's heading for somewhere you
> really don't want it to go you have to apply thew same force for the same
> time to stop it. Or in the likely event of wanting to stop it 10x quicker
> than that, multiply the force up by x10 too...
Actually, the answer is "No" it doesn't require an increased amount of
pressure to stop it. When I was playing with it at the woodworking show with
a sizable tablesaw on it, I was able to manoeuvre and stop or change
directions quite easily. So much so, that my wheelchair was only slightly
prone to rolling away when I was moving it around.
On Mar 9, 9:47 am, "Upscale" <[email protected]> wrote:
> "J. Clarke" <[email protected]> wrote in message
>
> > Before you spend 170 bucks you might want to try
> >http://amasci.com/amateur/hovercft.html.
>
> Could be a possibility as long as one doesn't mind risking their $1000-$3000
> pieces of machinery on some plywood, nuts, bolts and painter's drop sheets.
> Of course, it's unlikely that machinery would tip over or anything, but it
> would definitely be a jury rig setup and subject to problems.
It's a great idea, but I have questions about what happens to the
exhaust air. Some of it will escape along the floor level, and
wherever else it exhausts, and blow sawdust everywhere. Your typical
less-than-exemplary-housekeeping shop would probably present
problems. To move the machine you'd have to do a choice cleanup, move
the machine, then wait for the dust to settle before you can breathe
in there?
The manual says to have the area around the machine clear of dust and
debris...how far around and how clear? You don't need a floor you can
eat off of with a wheeled mobile base, just clear the bigger stuff out
of the way, and it doesn't matter how much crud is on top of the base.
R
"Lobby Dosser" <[email protected]> wrote in message
> > http://www.general.ca/pagemach/machines/10824_929.html
> WOW!!!! Sat here watching the video with my jaw dropped!! WOW!!!
> How much??
If I remember properly, it's somewhere around $250 CA. I'm sure they will
give you exact prices if you email them. I actually giggled while I was
pushing around a huge tablesaw within a confined area while peppering the
General company president with technical questions about the HoverPad. Being
a wheelchair user myself, I can think of dozens of applications for this
device, none of them having anything to do with woodoworking. The health
industry will flip on it's ear when it hears about this.
Anything online for the Access tool line?
http://www.general.ca/Access/pagemach/ang/welcome.html
I've been told that the prices for the 5 Access line woodworking machines
are the same as the regular line. That itself is great news since sales
figures will take considerable time for them to truly make a profit out of
them.
"Father Haskell" <[email protected]> wrote in message
>
> Way cool, especially how it makes heavy objects levitate
> 1/2" above the floor. I wonder if a sheet of plywood with a
> hole in the middle wouldn't do just as well.
Can't answer that. The time and effort I'd need running around to get the
parts and assemble one to my satisfaction would be put to better use my just
doing my job the equivalent amount of hours and buying the General version.
Guess which one I'd choose?
"Han" <[email protected]> wrote in message
news:[email protected]...
> PCPaul <[email protected]> wrote in
> news:[email protected]:
>
> > On Sun, 09 Mar 2008 08:47:34 -0500, Upscale wrote:
> >
> >> "J. Clarke" <[email protected]> wrote in message
> >>>
> >>> Before you spend 170 bucks you might want to try
> >>> http://amasci.com/amateur/hovercft.html.
> >>
> >> Could be a possibility as long as one doesn't mind risking their
> >> $1000-$3000 pieces of machinery on some plywood, nuts, bolts and
> >> painter's drop sheets. Of course, it's unlikely that machinery would
> >> tip over or anything, but it would definitely be a jury rig setup and
> >> subject to problems.
> >
> > I think the major issue applies to the Pro and homebuilt versions -
> > inertia.
> >
> > Yes, you can get it moving at some speed by pushing it with a single
> > finger for a while. *But* when you realise it's heading for somewhere
> > you really don't want it to go you have to apply thew same force for
> > the same time to stop it. Or in the likely event of wanting to stop it
> > 10x quicker than that, multiply the force up by x10 too...
> >
> I'd think that removing the air pressure would just about instantaneously
> stop the contraption. Then inertia and friction to the ground surface
> take over. Think Rube Goldberg consequences.
>
> --
> Best regards
> Han
> email address is invalid
The principle behind these isn't new, but this one has to be the flimsiest
design that I've ever seen.
Boeing has been designing and using hover pads to lift and move aircraft
sections into position since WWII. In fact, Boeing formed a subsidiary to
manufacture commercial versions of these for sale. They come in all sizes
(and cost), but the commercial ones are far too expensive for small shops
and hobbyists. A version was available some years back for use under
refrigerators, to be powered by a vacuum cleaner whenever the lady of the
house wanted to clean behind it, but I don't know if they are still
available. If you can find one it would likely be a cheap way to move your
cabinet saw.
Using only one large air chamber in the design produces a very tippy and
unstable unit that would not be very suitable for moving machines (remember
the hover craft show on Myth Busters?). If you look closely at General's
hover pad you will see that it is composed of many small hover pads. The use
of 3 or more give the platform the needed stability. In use, the pad only
needs the thinest of air film between the skirt and the floor for it to
work, but with only a very thin film of air, the floor has to be very
smooth. Increasing the air flow to increases the thickness of the air film
and will allow it to pass over less than perfect floors, but any significant
void in the floor surface will cause all of the air to leak out of the
affected chamber and the pad will bottom out and drag. In other words, they
will work great on a tile or concrete floor, until you try to cross over a
crack or other significant irregularity in the floor surface that the skirt
can't seal. When the air leaks out faster than it's coming in, the pad will
bottom out. A platform with 3 or 4 chambers under it will provide even
lifting and stability. Boeing makes single chamber pads, but they are
intended to be used in groups of 3 or more to distribute the load and
provide the needed stability. It's amazing how much weight they can lift and
move. 4,000 pounds can easily be moved using only 4-8 inch diameter pads
with only 6-11 pounds of air pressure. More air pressure raises the pad
slightly higher, allowing it to cross slight imperfections in the floor more
easily but it isn't necessary for most use, and it wastes a lot of air. It
doesn't take much air loss for the pad to collapse.
I have made some strong and reliable pads by gluing small new lawn tractor
inner tubes to 3/4 thick birch plywood (tractor tubes are available with
center holes as small as 4" dia and overall diameters of about 8"). The air
path for my pads is similar to the one in the link above, where the air
first enters the tube and then exits the tube into the center "hub hole" of
the tube, where it then leaks out between the bottom of the tube's surface
and the floor, forming the "air bearing". You will need to buy new tubes for
this project as their shape needs to be flat and not all stretched out of
shape, so they can be easily glued to the plywood. I use a wide ring of
automotive door gasket cement to bond the inner tube to the plywood and then
place a concrete block on top as a clamp "until the glue dries". The regular
filling stem is cut off and the resulting hole in the tube is glued to the
plywood so that it is in line with the air entrance hole (glue it well - no
leaks allowed around this point). Using a razor knife I then cut 4 slits
about 1/2" long around the center of the tube to allow the air to escape
from the inside of the tube into the center chamber, similar to the design
in the link above. Using rubber tractor inner tubes makes the pads survive
much longer than the 6 mil plastic, as small scratches from a rough floor
surface (pebbles, etc.) won't immediately tear the rubber like it will the
plastic. Many years ago I made some out of hemorroid cushions, but the ones
that are available now aren't very well suited for this. The old ones were
made from a vulcanized canvas material and the ones that are available now
are made of thin vinyl. (I got strange looks from the drugstore cashier
when I bought 4 at the same time - nobody gives you a second look when you
want to buy 4 inner tubes). I use my 18 cfm shop air compressor to power
them, with an air pressure regulator and hose connected to each pad (this
lets me vary the pressure and flow to one pad at a time) and my pads are all
made separate so I can put one under each corner, leg, etc. of whatever I
want to move. I can use 3, 4, or more if necessary (my compressor won't
likely handle more, but that's the plan). For a table saw or other small
machine 3 or 4 pads mounted on a board that's large enough to carry the tool
would work out fine. In a large commercial cabinet shop it would be handy to
have them separate so they could be placed under each corner of a very large
cabinet, etc. for movement around the shop floor.
Once up "on air" your tool will move very easily, so easy in fact, that you
will need to be careful not to get it moving too fast, or you may not be
able to stop it. It will stop very quickly if the air is shut off, but in a
one-man shop you won't have enough hands to hang on and shut off the air
too.
Charley
"Upscale" <[email protected]> wrote in message
news:[email protected]...
>
> "PCPaul" <[email protected]> wrote in message
> >
> > Yes, you can get it moving at some speed by pushing it with a single
> > finger for a while. *But* when you realise it's heading for somewhere
you
> > really don't want it to go you have to apply thew same force for the
same
> > time to stop it. Or in the likely event of wanting to stop it 10x
quicker
> > than that, multiply the force up by x10 too...
>
> Actually, the answer is "No" it doesn't require an increased amount of
> pressure to stop it. When I was playing with it at the woodworking show
with
> a sizable tablesaw on it, I was able to manoeuvre and stop or change
> directions quite easily. So much so, that my wheelchair was only slightly
> prone to rolling away when I was moving it around.
>
>
Momentum is the word.
It's easy to get something moving when it's on an air bearing, but there is
so little friction that it wants to keep moving at whatever speed you get it
up to. Instead of the normal friction slowdown that we are accustomed to,
you will need to supply very nearly the same force to stop it as you did
getting it moving. We are so accustomed to friction slowing and stoping
things that we move our bodies aren't really prepared to have to supply this
much negative force to stop something once it's started moving. After a few
minutes of pushing and pulling we quickly adjust to it, but the first
experience with a relatively heavy object on an air bearing (like 1-2 tons)
can be a bit of a surprise and an almost certain crash. I almost pushed a
3600 pound robot through a wall with my first experience. I got it stopped
in time, but nearly got pinned in the process.
Charley
"RicodJour" <[email protected]> wrote in message
news:f9cd7027-422d-4d38-8025-5d0028d9a05d@e39g2000hsf.googlegroups.com...
> On Mar 9, 3:27 pm, "Charley" <[email protected]> wrote:
> >
> > Boeing has been designing and using hover pads to lift and move aircraft
> > sections into position since WWII. In fact, Boeing formed a subsidiary
to
> > manufacture commercial versions of these for sale. They come in all
sizes
> > (and cost), but the commercial ones are far too expensive for small
shops
> > and hobbyists. A version was available some years back for use under
> > refrigerators, to be powered by a vacuum cleaner whenever the lady of
the
> > house wanted to clean behind it, but I don't know if they are still
> > available. If you can find one it would likely be a cheap way to move
your
> > cabinet saw.
> >
> > Using only one large air chamber in the design produces a very tippy and
> > unstable unit that would not be very suitable for moving machines
(remember
> > the hover craft show on Myth Busters?). If you look closely at General's
> > hover pad you will see that it is composed of many small hover pads. The
use
> > of 3 or more give the platform the needed stability. In use, the pad
only
> > needs the thinest of air film between the skirt and the floor for it to
> > work, but with only a very thin film of air, the floor has to be very
> > smooth. Increasing the air flow to increases the thickness of the air
film
> > and will allow it to pass over less than perfect floors, but any
significant
> > void in the floor surface will cause all of the air to leak out of the
> > affected chamber and the pad will bottom out and drag. In other words,
they
> > will work great on a tile or concrete floor, until you try to cross over
a
> > crack or other significant irregularity in the floor surface that the
skirt
> > can't seal. When the air leaks out faster than it's coming in, the pad
will
> > bottom out. A platform with 3 or 4 chambers under it will provide even
> > lifting and stability. Boeing makes single chamber pads, but they are
> > intended to be used in groups of 3 or more to distribute the load and
> > provide the needed stability. It's amazing how much weight they can lift
and
> > move. 4,000 pounds can easily be moved using only 4-8 inch diameter pads
> > with only 6-11 pounds of air pressure. More air pressure raises the pad
> > slightly higher, allowing it to cross slight imperfections in the floor
more
> > easily but it isn't necessary for most use, and it wastes a lot of air.
It
> > doesn't take much air loss for the pad to collapse.
> >
> > I have made some strong and reliable pads by gluing small new lawn
tractor
> > inner tubes to 3/4 thick birch plywood (tractor tubes are available with
> > center holes as small as 4" dia and overall diameters of about 8"). The
air
> > path for my pads is similar to the one in the link above, where the air
> > first enters the tube and then exits the tube into the center "hub hole"
of
> > the tube, where it then leaks out between the bottom of the tube's
surface
> > and the floor, forming the "air bearing". You will need to buy new tubes
for
> > this project as their shape needs to be flat and not all stretched out
of
> > shape, so they can be easily glued to the plywood. I use a wide ring of
> > automotive door gasket cement to bond the inner tube to the plywood and
then
> > place a concrete block on top as a clamp "until the glue dries". The
regular
> > filling stem is cut off and the resulting hole in the tube is glued to
the
> > plywood so that it is in line with the air entrance hole (glue it well -
no
> > leaks allowed around this point). Using a razor knife I then cut 4 slits
> > about 1/2" long around the center of the tube to allow the air to
escape
> > from the inside of the tube into the center chamber, similar to the
design
> > in the link above. Using rubber tractor inner tubes makes the pads
survive
> > much longer than the 6 mil plastic, as small scratches from a rough
floor
> > surface (pebbles, etc.) won't immediately tear the rubber like it will
the
> > plastic. Many years ago I made some out of hemorroid cushions, but the
ones
> > that are available now aren't very well suited for this. The old ones
were
> > made from a vulcanized canvas material and the ones that are available
now
> > are made of thin vinyl. (I got strange looks from the drugstore cashier
> > when I bought 4 at the same time - nobody gives you a second look when
you
> > want to buy 4 inner tubes). I use my 18 cfm shop air compressor to power
> > them, with an air pressure regulator and hose connected to each pad
(this
> > lets me vary the pressure and flow to one pad at a time) and my pads are
all
> > made separate so I can put one under each corner, leg, etc. of whatever
I
> > want to move. I can use 3, 4, or more if necessary (my compressor won't
> > likely handle more, but that's the plan). For a table saw or other small
> > machine 3 or 4 pads mounted on a board that's large enough to carry the
tool
> > would work out fine. In a large commercial cabinet shop it would be
handy to
> > have them separate so they could be placed under each corner of a very
large
> > cabinet, etc. for movement around the shop floor.
> >
> > Once up "on air" your tool will move very easily, so easy in fact, that
you
> > will need to be careful not to get it moving too fast, or you may not be
> > able to stop it. It will stop very quickly if the air is shut off, but
in a
> > one-man shop you won't have enough hands to hang on and shut off the air
> > too.
>
> How clean does the area around the saw have to be and how much dust
> gets kicked up? You mentioned ~10 PSI for the Boeing thing, what do
> you run yours at?
>
> The hemorrhoid cushion part was hilarious. Reminded me of a cyclist
> buddy telling me about shopping for support hose to help with his
> varicose veins and having the clerk in the lingerie department give
> him odd looks when he asked for a pair in his size. ;)
>
> R
The air pressure that is needed depends on how large the pads are, how heavy
the load is, and how smooth the floor is. The floor smoothness and the
condition of the pad skirt's bottom surface significantly affects the volume
of air that is needed. Of course, some air has to leak out to provide the
air bearing function, but the less air escaping from under the pads, the
less dust will be blown around. I always sweep my floor before using them,
but I don't make it perfectly clean. Sometimes I'll see some dust being
blown around on the floor but I never get major dust clouds in the room from
them. I guess it really all depends on how good the skirt to floor seal is.
They used a vacuum cleaner to inflate the cheaply made pads in the link,
which is high air volume and very little pressure, probably only a few psi.
I use my shop compressed air system, a 3/8 line to supply line my regulator
bank and 1/4 inch lines from the regulators to each pad. My air system has
an 80 gal tank and 18 cfm compressor and I've never run out of enough air to
run them, but if I was to run a pad over an 1/8 inch crack in the floor, the
pad would collapse. I can sometimes crank up the pressure (and thus the
volume) to a collapsed pad to get over small defects, but it's best to make
sure that the floor doesn't have any significant voids in it where you are
going to be using the pads. We used bondo and duct tape as a temporary floor
fix to get the pads to work over some bad spots in the floor when I was
using the commercial pads to move the robots, but rough floors can be a
major problem. Floor defects can easily damage the rubber skirt seals on the
pads as well as pose the significant air leak problems. To lift an 800 lb
table saw with 3 - 8 inch diameter pads on a tile floor you probably will
only need about 2 or 3 psi. I rarely move my tools with my pads any more as
my present shop is relatively small and tool locations are stable. Lately,
they seem to just get used for moving big clumsy projects where it is very
inconvenient to try to move them around with dollys, etc. or sometimes when
I'm the only one in the shop and I want to move something myself. Once the
pads are in place under a project I usually leave them there until the
project is finished, so it can be moved or turned around for the convenience
of getting to the other side, etc.
I didn't mention in the previous note that I have been adding a small circle
of 1/2" plywood in the center of my pads to take the load off the rubber
skirt material when the pads are not inflated. I found that this helps to
protect the rubber should a side force (bump) be applied while the pads are
deflated. They can easily tear if a load is on the rubber alone and the load
is pushed sideways. With the plywood in the center the weight of the load is
on it and not on the rubber.
Charley
"Father Haskell" <[email protected]> wrote in message
news:[email protected]...
> On Mar 10, 8:18 am, "Upscale" <[email protected]> wrote:
> > "Father Haskell" <[email protected]> wrote in message
> >
> > > Way cool, especially how it makes heavy objects levitate
> > > 1/2" above the floor. I wonder if a sheet of plywood with a
> > > hole in the middle wouldn't do just as well.
> >
> > Can't answer that. The time and effort I'd need running around to get
the
> > parts and assemble one to my satisfaction would be put to better use my
just
> > doing my job the equivalent amount of hours and buying the General
version.
> > Guess which one I'd choose?
>
> 1/2 sheet 1/2" plywood, 1 2" cutoff 3/8" pipe, hose, clamp, epoxy,
> 30 seconds labor to drill the hole in the center of the sheet.
If you look closely at the General hoverpad you will find that it's really
many small hoverpads on a big sheet. Making one big one will give you
stability problems. Multiple small ones like 3 or maybe 4 on one common
sheet will give you the stability of the General's version.
Charley
"Father Haskell" <[email protected]> wrote in message
news:a8e213d2-631c-45f7-8cdc-32bb08bb3a9d@e60g2000hsh.googlegroups.com...
> On Mar 10, 9:28 pm, "Charley" <[email protected]> wrote:
> > "Father Haskell" <[email protected]> wrote in message
> >
> > news:[email protected]...
> >
> >
> >
> > > On Mar 10, 8:18 am, "Upscale" <[email protected]> wrote:
> > > > "Father Haskell" <[email protected]> wrote in message
> >
> > > > > Way cool, especially how it makes heavy objects levitate
> > > > > 1/2" above the floor. I wonder if a sheet of plywood with a
> > > > > hole in the middle wouldn't do just as well.
> >
> > > > Can't answer that. The time and effort I'd need running around to
get
> > the
> > > > parts and assemble one to my satisfaction would be put to better use
my
> > just
> > > > doing my job the equivalent amount of hours and buying the General
> > version.
> > > > Guess which one I'd choose?
> >
> > > 1/2 sheet 1/2" plywood, 1 2" cutoff 3/8" pipe, hose, clamp, epoxy,
> > > 30 seconds labor to drill the hole in the center of the sheet.
> >
> > If you look closely at the General hoverpad you will find that it's
really
> > many small hoverpads on a big sheet. Making one big one will give you
> > stability problems. Multiple small ones like 3 or maybe 4 on one common
> > sheet will give you the stability of the General's version.
> >
> > Charley
>
> How hard would it be to glue up a manifold from 1/2" PVC?
Actually, my pads have a sort of manifold made into them. I groove one sheet
of 3/4 ply and then sandwich/glue it on top of another piece to allow me to
have the air inlet enter along the middle of one edge. I epoxy any voids in
the plywood groove and also epoxy a quick connect air line fitting into the
hole (bored out to fit) in the edge. It's positioned so that nothing
interferes with the flat top surface. That way the pad will fit under
anything. To be sure of a good glue-up of the two sheet joint and have no
leakage I make sure that I run an unbroken bead of glue all the way around
the groove area so that it seals real well when put together. Then I hold
the sheets together with clamps followed by screws "until the glue dries".
Of course, the screws remain when the clamps are removed. If you were making
several small pads on a large sheet, manifolding between them this way may
not be such a good idea. Maybe you could sandwich a piece of pipe in the
groove to minimize the possibility of leakage.
I have never made a multi pad assembly. All my pads have been single and
each one has had it's own air line from it's own regulator, so I can feed
each one and control it separately. I don't know how they would respond if
they were all manifolded together.
Charley
Seeing that they were running it from a small air tank, I assume the
volume of air actually escaping is pretty low. Once the physics get it
up and floating, you just need a dribble of air to keep it there. They
show a small amount of dust being displaced along the edge on one of
the close-ups and you can see it is not blown but a few inches to the
side.
Plus, they say it can be cut to shape. That is really cool. Looks like
a great packaging of an existing idea. I'd say watch for Craftsman and
Grizz to have the mass market and low cost versions out soon.
BW
On Mar 9, 7:20=A0am, RicodJour <[email protected]> wrote:
> On Mar 9, 9:47 am, "Upscale" <[email protected]> wrote:
>
> > "J. Clarke" <[email protected]> wrote in message
>
> > > Before you spend 170 bucks you might want to try
> > >http://amasci.com/amateur/hovercft.html.
>
> > Could be a possibility as long as one doesn't mind risking their $1000-$=
3000
> > pieces of machinery on some plywood, nuts, bolts and painter's drop shee=
ts.
> > Of course, it's unlikely that machinery would tip over or anything, but =
it
> > would definitely be a jury rig setup and subject to problems.
>
> It's a great idea, but I have questions about what happens to the
> exhaust air. =A0Some of it will escape along the floor level, and
> wherever else it exhausts, and blow sawdust everywhere. =A0Your typical
> less-than-exemplary-housekeeping shop would probably present
> problems. =A0To move the machine you'd have to do a choice cleanup, move
> the machine, then wait for the dust to settle before you can breathe
> in there?
>
> The manual says to have the area around the machine clear of dust and
> debris...how far around and how clear? =A0You don't need a floor you can
> eat off of with a wheeled mobile base, just clear the bigger stuff out
> of the way, and it doesn't matter how much crud is on top of the base.
>
> R
"Father Haskell" <[email protected]> wrote in message
>
> Depends what supplies you have on hand, I guess. I do
> plumbing, so I have lots of spare 1/2" PVC pipe and fittings
> laying around the shop.
That's the difference then. For some things I like to build them from
scratch like setting up and organizing a workshop, but other things I like
them to just be there for use. The HoverPad would fall into that category as
far as I'm concerned. I'd just want to use it and not worry about saving a
few dollars building one. It's unlikely I'd be saving any time, so building
one from scratch is just not a consideration.
On Mar 9, 2:29=A0am, "Upscale" <[email protected]> wrote:
> Well, for you woodworkers with reasonably flat workshop floors, General ha=
s
> come out with the HoverPad. It's a mobile base for heavy machine tools bas=
ed
> on Hovercraft technology.
>
> I was at the Toronto Woodworking show last weekend to take part in the
> premiere presentation of their new line of Access machine tools designed f=
or
> people in wheelchairs, who like to sit or who are of lower stature. While
> there, I had a good look at their HoverPad. Essentially, you can push
> hundreds of pounds of machine tool around with one finger. I can think of =
a
> dozen uses for one of these. They're not much more expensive than other
> decent mobile bases, can be cut to size and can be run on really low end
> compressors.
>
> So for those of you interested, here's the specs and a video.http://www.ge=
neral.ca/pagemach/machines/10824_929.html
Nice to see somebody engineer this out to an affordable level. The
tech, as you know, is old hat. I seen those used when moving 100 ton
presses. Here's a supplier:
http://www.hovair.com/products.htm
What I did not want to do, is rain on anybody's parade. But the blow-
up dust is a huge issue, as mentioned in here already.
The nice thing about the whole concept is that it easily done by the
little guys on the cheap.
I see guys move skids of granite cut-offs all the time. Whole sheets
of granite moved on pucks, home-made from 3/4" UHMW, where air
pressure is applied to move the piece, and then flipped over with a 3-
way valve to vacuum to hold while machining.
Their problem is water flying all over the place.
To make your own? I was thinking small inner tubes... wheel-barrow/
lawn-tractor style. Cut them along the external and internal
circumference... maybe, if small enough, leave them whole and
perforate them on one side? Insert them in a channel routed out of a
slab (doubled) of MDF with a bowl bit and a circle cutter? Maybe a
bicycle inner tube stretched into a rectangular slot with rounded
corners? The inlet is already on the tube...even...
Come ON PEOPLE!! We're a smart bunch here. One groove for the tube,
one groove outside that tubed perimeter for the shop vac? I want ideas
on my desk by night fall. hehehehe
"Lobby Dosser" <[email protected]> wrote in message
> May I ask what kind of chair you use? Insurance paid for a rental for me
> for a year and then the provider said it was mine. But, it's too heavy
> for me to wrestle into the truck - an invacare, blue seat and lots of
> chrome model. I'm looking for something light weight - <30# or so.
I use comfortable manual heavy duty Invacare inside and a foldable Quickie 2
when I go out. The Invacare outside would just have me spinning my wheels in
the snow.
On Mar 9, 2:29 am, "Upscale" <[email protected]> wrote:
> Well, for you woodworkers with reasonably flat workshop floors, General has
> come out with the HoverPad. It's a mobile base for heavy machine tools based
> on Hovercraft technology.
>
> I was at the Toronto Woodworking show last weekend to take part in the
> premiere presentation of their new line of Access machine tools designed for
> people in wheelchairs, who like to sit or who are of lower stature. While
> there, I had a good look at their HoverPad. Essentially, you can push
> hundreds of pounds of machine tool around with one finger. I can think of a
> dozen uses for one of these. They're not much more expensive than other
> decent mobile bases, can be cut to size and can be run on really low end
> compressors.
>
> So for those of you interested, here's the specs and a video.http://www.general.ca/pagemach/machines/10824_929.html
Way cool, especially how it makes heavy objects levitate
1/2" above the floor. I wonder if a sheet of plywood with a
hole in the middle wouldn't do just as well.
On Mar 9, 10:20 am, RicodJour <[email protected]> wrote:
>
> ...
>
> It's a great idea, but I have questions about what happens to the
> exhaust air. Some of it will escape along the floor level, and
> wherever else it exhausts, and blow sawdust everywhere. Your typical
> less-than-exemplary-housekeeping shop would probably present
> problems. To move the machine you'd have to do a choice cleanup, move
> the machine, then wait for the dust to settle before you can breathe
> in there?
Good incentive for an inveterate slob like me
to change his habits. Cleaning one's work area
frequently is a very good practice. Aside from the
immediate safety aspect, it is a good excuse
to take a break and plan the next operation.
OTOH when turning there is certain charm to standing
in the middle of huge pile of chips.
--
FF
On Sun, 09 Mar 2008 08:47:34 -0500, Upscale wrote:
> "J. Clarke" <[email protected]> wrote in message
>>
>> Before you spend 170 bucks you might want to try
>> http://amasci.com/amateur/hovercft.html.
>
> Could be a possibility as long as one doesn't mind risking their
> $1000-$3000 pieces of machinery on some plywood, nuts, bolts and
> painter's drop sheets. Of course, it's unlikely that machinery would tip
> over or anything, but it would definitely be a jury rig setup and
> subject to problems.
I think the major issue applies to the Pro and homebuilt versions -
inertia.
Yes, you can get it moving at some speed by pushing it with a single
finger for a while. *But* when you realise it's heading for somewhere you
really don't want it to go you have to apply thew same force for the same
time to stop it. Or in the likely event of wanting to stop it 10x quicker
than that, multiply the force up by x10 too...
"J. Clarke" <[email protected]> wrote:
>
> Before you spend 170 bucks you might want to try
> http://amasci.com/amateur/hovercft.html.
>
>
>
Thanks. I've bookmarked that one too.
"Upscale" <[email protected]> wrote:
> Well, for you woodworkers with reasonably flat workshop floors,
> General has come out with the HoverPad. It's a mobile base for heavy
> machine tools based on Hovercraft technology.
>
> I was at the Toronto Woodworking show last weekend to take part in the
> premiere presentation of their new line of Access machine tools
> designed for people in wheelchairs, who like to sit or who are of
> lower stature. While there, I had a good look at their HoverPad.
> Essentially, you can push hundreds of pounds of machine tool around
> with one finger. I can think of a dozen uses for one of these. They're
> not much more expensive than other decent mobile bases, can be cut to
> size and can be run on really low end compressors.
>
> So for those of you interested, here's the specs and a video.
> http://www.general.ca/pagemach/machines/10824_929.html
>
>
>
>
WOW!!!! Sat here watching the video with my jaw dropped!! WOW!!!
How much?? Anything online for the Access tool line?
Thanks!
"Upscale" <[email protected]> wrote:
>
> "Lobby Dosser" <[email protected]> wrote in message
>> May I ask what kind of chair you use? Insurance paid for a rental for
>> me for a year and then the provider said it was mine. But, it's too
>> heavy for me to wrestle into the truck - an invacare, blue seat and
>> lots of chrome model. I'm looking for something light weight - <30#
>> or so.
>
> I use comfortable manual heavy duty Invacare inside and a foldable
> Quickie 2 when I go out. The Invacare outside would just have me
> spinning my wheels in the snow.
>
>
>
Thanks.
PCPaul <[email protected]> wrote in
news:[email protected]:
> On Sun, 09 Mar 2008 08:47:34 -0500, Upscale wrote:
>
>> "J. Clarke" <[email protected]> wrote in message
>>>
>>> Before you spend 170 bucks you might want to try
>>> http://amasci.com/amateur/hovercft.html.
>>
>> Could be a possibility as long as one doesn't mind risking their
>> $1000-$3000 pieces of machinery on some plywood, nuts, bolts and
>> painter's drop sheets. Of course, it's unlikely that machinery would
>> tip over or anything, but it would definitely be a jury rig setup and
>> subject to problems.
>
> I think the major issue applies to the Pro and homebuilt versions -
> inertia.
>
> Yes, you can get it moving at some speed by pushing it with a single
> finger for a while. *But* when you realise it's heading for somewhere
> you really don't want it to go you have to apply thew same force for
> the same time to stop it. Or in the likely event of wanting to stop it
> 10x quicker than that, multiply the force up by x10 too...
>
I'd think that removing the air pressure would just about instantaneously
stop the contraption. Then inertia and friction to the ground surface
take over. Think Rube Goldberg consequences.
--
Best regards
Han
email address is invalid
On Mar 10, 9:28 pm, "Charley" <[email protected]> wrote:
> "Father Haskell" <[email protected]> wrote in message
>
> news:[email protected]...
>
>
>
> > On Mar 10, 8:18 am, "Upscale" <[email protected]> wrote:
> > > "Father Haskell" <[email protected]> wrote in message
>
> > > > Way cool, especially how it makes heavy objects levitate
> > > > 1/2" above the floor. I wonder if a sheet of plywood with a
> > > > hole in the middle wouldn't do just as well.
>
> > > Can't answer that. The time and effort I'd need running around to get
> the
> > > parts and assemble one to my satisfaction would be put to better use my
> just
> > > doing my job the equivalent amount of hours and buying the General
> version.
> > > Guess which one I'd choose?
>
> > 1/2 sheet 1/2" plywood, 1 2" cutoff 3/8" pipe, hose, clamp, epoxy,
> > 30 seconds labor to drill the hole in the center of the sheet.
>
> If you look closely at the General hoverpad you will find that it's really
> many small hoverpads on a big sheet. Making one big one will give you
> stability problems. Multiple small ones like 3 or maybe 4 on one common
> sheet will give you the stability of the General's version.
>
> Charley
How hard would it be to glue up a manifold from 1/2" PVC?
"Upscale" <[email protected]> wrote:
>
> "Lobby Dosser" <[email protected]> wrote in message
>> > http://www.general.ca/pagemach/machines/10824_929.html
>> WOW!!!! Sat here watching the video with my jaw dropped!! WOW!!!
>
>> How much??
> If I remember properly, it's somewhere around $250 CA. I'm sure they
> will give you exact prices if you email them.
I dug around a bit more and found $170 for the small and $250 for the
large.
> I actually giggled while
> I was pushing around a huge tablesaw within a confined area while
> peppering the General company president with technical questions about
> the HoverPad.
I can believe it! The folks in the video look like they're having a good
time.
> Being a wheelchair user myself, I can think of dozens of
> applications for this device, none of them having anything to do with
> woodoworking.
I'm out of my wheelchair now, but still need it for long distances and
anything that requires standing without leaning on something - a
tablesaw, for example.
Now I need to figure out the best way to mount everything to minimize the
number of pads needed.
> The health industry will flip on it's ear when it hears
> about this.
Lots of places will flip.
>
> Anything online for the Access tool line?
> http://www.general.ca/Access/pagemach/ang/welcome.html
>
> I've been told that the prices for the 5 Access line woodworking
> machines are the same as the regular line. That itself is great news
Yeah. Normally the prices would be higher. Just like "computer" furniture
that one word adds 40% to the price.
> since sales figures will take considerable time for them to truly make
> a profit out of them.
Thanks for that, I couldn't seem to find it.
May I ask what kind of chair you use? Insurance paid for a rental for me
for a year and then the provider said it was mine. But, it's too heavy
for me to wrestle into the truck - an invacare, blue seat and lots of
chrome model. I'm looking for something light weight - <30# or so.
>
>
>
>
On Mar 10, 8:18 am, "Upscale" <[email protected]> wrote:
> "Father Haskell" <[email protected]> wrote in message
>
> > Way cool, especially how it makes heavy objects levitate
> > 1/2" above the floor. I wonder if a sheet of plywood with a
> > hole in the middle wouldn't do just as well.
>
> Can't answer that. The time and effort I'd need running around to get the
> parts and assemble one to my satisfaction would be put to better use my just
> doing my job the equivalent amount of hours and buying the General version.
> Guess which one I'd choose?
1/2 sheet 1/2" plywood, 1 2" cutoff 3/8" pipe, hose, clamp, epoxy,
30 seconds labor to drill the hole in the center of the sheet.
"J. Clarke" <[email protected]> wrote in message
>
> Before you spend 170 bucks you might want to try
> http://amasci.com/amateur/hovercft.html.
Could be a possibility as long as one doesn't mind risking their $1000-$3000
pieces of machinery on some plywood, nuts, bolts and painter's drop sheets.
Of course, it's unlikely that machinery would tip over or anything, but it
would definitely be a jury rig setup and subject to problems.
On Mar 11, 3:29=A0pm, dpb <[email protected]> wrote:
> Robatoy wrote:
> > On Mar 11, 12:54 pm, Fred the Red Shirt <[email protected]>
> > wrote:
>
> >> OTOH when turning there is certain charm to standing
> >> in the middle of huge pile of chips.
>
> > I have yet to hear a blacksmith say that after shoeing a horse.
>
> That particular blacksmith would be a farrier...
>
Actually, he could belong to any religion.
On Mar 11, 12:54=A0pm, Fred the Red Shirt <[email protected]>
wrote:
>
> OTOH when turning there is certain charm to standing
> in the middle of huge pile of chips.
>
I have yet to hear a blacksmith say that after shoeing a horse.
On Mar 11, 11:57 am, "Charley" <[email protected]> wrote:
> "Father Haskell" <[email protected]> wrote in message
>
> news:a8e213d2-631c-45f7-8cdc-32bb08bb3a9d@e60g2000hsh.googlegroups.com...
>
>
>
> > On Mar 10, 9:28 pm, "Charley" <[email protected]> wrote:
> > > "Father Haskell" <[email protected]> wrote in message
>
> > >news:[email protected]...
>
> > > > On Mar 10, 8:18 am, "Upscale" <[email protected]> wrote:
> > > > > "Father Haskell" <[email protected]> wrote in message
>
> > > > > > Way cool, especially how it makes heavy objects levitate
> > > > > > 1/2" above the floor. I wonder if a sheet of plywood with a
> > > > > > hole in the middle wouldn't do just as well.
>
> > > > > Can't answer that. The time and effort I'd need running around to
> get
> > > the
> > > > > parts and assemble one to my satisfaction would be put to better use
> my
> > > just
> > > > > doing my job the equivalent amount of hours and buying the General
> > > version.
> > > > > Guess which one I'd choose?
>
> > > > 1/2 sheet 1/2" plywood, 1 2" cutoff 3/8" pipe, hose, clamp, epoxy,
> > > > 30 seconds labor to drill the hole in the center of the sheet.
>
> > > If you look closely at the General hoverpad you will find that it's
> really
> > > many small hoverpads on a big sheet. Making one big one will give you
> > > stability problems. Multiple small ones like 3 or maybe 4 on one common
> > > sheet will give you the stability of the General's version.
>
> > > Charley
>
> > How hard would it be to glue up a manifold from 1/2" PVC?
>
> Actually, my pads have a sort of manifold made into them. I groove one sheet
> of 3/4 ply and then sandwich/glue it on top of another piece to allow me to
> have the air inlet enter along the middle of one edge. I epoxy any voids in
> the plywood groove and also epoxy a quick connect air line fitting into the
> hole (bored out to fit) in the edge. It's positioned so that nothing
> interferes with the flat top surface. That way the pad will fit under
> anything. To be sure of a good glue-up of the two sheet joint and have no
> leakage I make sure that I run an unbroken bead of glue all the way around
> the groove area so that it seals real well when put together. Then I hold
> the sheets together with clamps followed by screws "until the glue dries".
> Of course, the screws remain when the clamps are removed. If you were making
> several small pads on a large sheet, manifolding between them this way may
> not be such a good idea. Maybe you could sandwich a piece of pipe in the
> groove to minimize the possibility of leakage.
>
> I have never made a multi pad assembly. All my pads have been single and
> each one has had it's own air line from it's own regulator, so I can feed
> each one and control it separately. I don't know how they would respond if
> they were all manifolded together.
Depends what supplies you have on hand, I guess. I do
plumbing, so I have lots of spare 1/2" PVC pipe and fittings
laying around the shop.
On Mar 9, 3:27 pm, "Charley" <[email protected]> wrote:
>
> Boeing has been designing and using hover pads to lift and move aircraft
> sections into position since WWII. In fact, Boeing formed a subsidiary to
> manufacture commercial versions of these for sale. They come in all sizes
> (and cost), but the commercial ones are far too expensive for small shops
> and hobbyists. A version was available some years back for use under
> refrigerators, to be powered by a vacuum cleaner whenever the lady of the
> house wanted to clean behind it, but I don't know if they are still
> available. If you can find one it would likely be a cheap way to move your
> cabinet saw.
>
> Using only one large air chamber in the design produces a very tippy and
> unstable unit that would not be very suitable for moving machines (remember
> the hover craft show on Myth Busters?). If you look closely at General's
> hover pad you will see that it is composed of many small hover pads. The use
> of 3 or more give the platform the needed stability. In use, the pad only
> needs the thinest of air film between the skirt and the floor for it to
> work, but with only a very thin film of air, the floor has to be very
> smooth. Increasing the air flow to increases the thickness of the air film
> and will allow it to pass over less than perfect floors, but any significant
> void in the floor surface will cause all of the air to leak out of the
> affected chamber and the pad will bottom out and drag. In other words, they
> will work great on a tile or concrete floor, until you try to cross over a
> crack or other significant irregularity in the floor surface that the skirt
> can't seal. When the air leaks out faster than it's coming in, the pad will
> bottom out. A platform with 3 or 4 chambers under it will provide even
> lifting and stability. Boeing makes single chamber pads, but they are
> intended to be used in groups of 3 or more to distribute the load and
> provide the needed stability. It's amazing how much weight they can lift and
> move. 4,000 pounds can easily be moved using only 4-8 inch diameter pads
> with only 6-11 pounds of air pressure. More air pressure raises the pad
> slightly higher, allowing it to cross slight imperfections in the floor more
> easily but it isn't necessary for most use, and it wastes a lot of air. It
> doesn't take much air loss for the pad to collapse.
>
> I have made some strong and reliable pads by gluing small new lawn tractor
> inner tubes to 3/4 thick birch plywood (tractor tubes are available with
> center holes as small as 4" dia and overall diameters of about 8"). The air
> path for my pads is similar to the one in the link above, where the air
> first enters the tube and then exits the tube into the center "hub hole" of
> the tube, where it then leaks out between the bottom of the tube's surface
> and the floor, forming the "air bearing". You will need to buy new tubes for
> this project as their shape needs to be flat and not all stretched out of
> shape, so they can be easily glued to the plywood. I use a wide ring of
> automotive door gasket cement to bond the inner tube to the plywood and then
> place a concrete block on top as a clamp "until the glue dries". The regular
> filling stem is cut off and the resulting hole in the tube is glued to the
> plywood so that it is in line with the air entrance hole (glue it well - no
> leaks allowed around this point). Using a razor knife I then cut 4 slits
> about 1/2" long around the center of the tube to allow the air to escape
> from the inside of the tube into the center chamber, similar to the design
> in the link above. Using rubber tractor inner tubes makes the pads survive
> much longer than the 6 mil plastic, as small scratches from a rough floor
> surface (pebbles, etc.) won't immediately tear the rubber like it will the
> plastic. Many years ago I made some out of hemorroid cushions, but the ones
> that are available now aren't very well suited for this. The old ones were
> made from a vulcanized canvas material and the ones that are available now
> are made of thin vinyl. (I got strange looks from the drugstore cashier
> when I bought 4 at the same time - nobody gives you a second look when you
> want to buy 4 inner tubes). I use my 18 cfm shop air compressor to power
> them, with an air pressure regulator and hose connected to each pad (this
> lets me vary the pressure and flow to one pad at a time) and my pads are all
> made separate so I can put one under each corner, leg, etc. of whatever I
> want to move. I can use 3, 4, or more if necessary (my compressor won't
> likely handle more, but that's the plan). For a table saw or other small
> machine 3 or 4 pads mounted on a board that's large enough to carry the tool
> would work out fine. In a large commercial cabinet shop it would be handy to
> have them separate so they could be placed under each corner of a very large
> cabinet, etc. for movement around the shop floor.
>
> Once up "on air" your tool will move very easily, so easy in fact, that you
> will need to be careful not to get it moving too fast, or you may not be
> able to stop it. It will stop very quickly if the air is shut off, but in a
> one-man shop you won't have enough hands to hang on and shut off the air
> too.
How clean does the area around the saw have to be and how much dust
gets kicked up? You mentioned ~10 PSI for the Boeing thing, what do
you run yours at?
The hemorrhoid cushion part was hilarious. Reminded me of a cyclist
buddy telling me about shopping for support hose to help with his
varicose veins and having the clerk in the lingerie department give
him odd looks when he asked for a pair in his size. ;)
R
Lobby Dosser wrote:
> "Upscale" <[email protected]> wrote:
>
>> Well, for you woodworkers with reasonably flat workshop floors,
>> General has come out with the HoverPad. It's a mobile base for
>> heavy
>> machine tools based on Hovercraft technology.
>>
>> I was at the Toronto Woodworking show last weekend to take part in
>> the premiere presentation of their new line of Access machine tools
>> designed for people in wheelchairs, who like to sit or who are of
>> lower stature. While there, I had a good look at their HoverPad.
>> Essentially, you can push hundreds of pounds of machine tool around
>> with one finger. I can think of a dozen uses for one of these.
>> They're not much more expensive than other decent mobile bases, can
>> be cut to size and can be run on really low end compressors.
>>
>> So for those of you interested, here's the specs and a video.
>> http://www.general.ca/pagemach/machines/10824_929.html
>>
>>
>>
>>
>
> WOW!!!! Sat here watching the video with my jaw dropped!! WOW!!!
>
> How much?? Anything online for the Access tool line?
Before you spend 170 bucks you might want to try
http://amasci.com/amateur/hovercft.html.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
PCPaul wrote:
> On Sun, 09 Mar 2008 08:47:34 -0500, Upscale wrote:
>
>> "J. Clarke" <[email protected]> wrote in message
>>>
>>> Before you spend 170 bucks you might want to try
>>> http://amasci.com/amateur/hovercft.html.
>>
>> Could be a possibility as long as one doesn't mind risking their
>> $1000-$3000 pieces of machinery on some plywood, nuts, bolts and
>> painter's drop sheets. Of course, it's unlikely that machinery
>> would
>> tip over or anything, but it would definitely be a jury rig setup
>> and
>> subject to problems.
What risks? When the air's not on it's a piece of plywood sitting on
the floor. When the air is on either it lifts or it doesn't. If it
doesn't then you've wasted what, ten bucks? If it does, how high is
it going to lift? 1/8 of an inch would be quite a lot.
> I think the major issue applies to the Pro and homebuilt versions -
> inertia.
>
> Yes, you can get it moving at some speed by pushing it with a single
> finger for a while. *But* when you realise it's heading for
> somewhere
> you really don't want it to go you have to apply thew same force for
> the same time to stop it. Or in the likely event of wanting to stop
> it 10x quicker than that, multiply the force up by x10 too...
Kill the air and down it goes. If it's going real fast _then_ it may
tip.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Robatoy wrote:
> On Mar 11, 12:54 pm, Fred the Red Shirt <[email protected]>
> wrote:
>
>> OTOH when turning there is certain charm to standing
>> in the middle of huge pile of chips.
>>
>
> I have yet to hear a blacksmith say that after shoeing a horse.
That particular blacksmith would be a farrier...
--
Robatoy wrote:
> On Mar 11, 3:29 pm, dpb <[email protected]> wrote:
>> Robatoy wrote:
>>> On Mar 11, 12:54 pm, Fred the Red Shirt <[email protected]>
>>> wrote:
>>>> OTOH when turning there is certain charm to standing
>>>> in the middle of huge pile of chips.
>>> I have yet to hear a blacksmith say that after shoeing a horse.
>> That particular blacksmith would be a farrier...
>>
> Actually, he could belong to any religion.
:) (Which I also _meant_ to include earlier...)
--