Delta Scroll Saw Hold Down-work tends to jump

"Fritz" <[email protected]> wrote in message
news:[email protected]...
> OK and many thanks to the responses. I use a scroll saw very little
> and mainly to cut 1mm aluminum templates. Working with large sheets
> (12"x12") is no problem until I get to the edges. Small pieces (2"x2")
> are really tough. I took the foot off and worked really slowly
> yesterday with some improvement but still get a good kick once in a
> while when doing a tight turn. If I get ambitious I will refabricate a
> better hold down.

Couldn't you put the aluminum in between some hardboard or something? Put
some double sided tape on the peices to stabilize it as a unit. Do the
cutting and then take apart the layers.

I have dome this when bandsawing sheet metal. One nice thing about
hardboard is that one side is smooth and the other is textured. So you can
make your sandwich with the smooth side on the bottom and the textured side
on top. That way the sandwich moves smoothly on the metal table. And you
have some texture on top that helps you hang on to it with fingers.

OK and many thanks to the responses. I use a scroll saw very little
and mainly to cut 1mm aluminum templates. Working with large sheets
(12"x12") is no problem until I get to the edges. Small pieces (2"x2")
are really tough. I took the foot off and worked really slowly
yesterday with some improvement but still get a good kick once in a
while when doing a tight turn. If I get ambitious I will refabricate a
better hold down.
Nice web-page Phil!

Thanks Again
Fritz

On Mon, 16 Feb 2009 17:56:44 -0800, Fritz wrote:

> I have an SS350 Delta Scroll Saw. I find that the work tends to jump a
> lot with this saw. (of course I am using a new blade properly mounted
> and proper for the stock being cut). I assume that this is caused by the
> springy nature of the hold down foot? I have bent it a bit to increase
> the tension and adjusted the extension, close to the work but I still
> find that thin pieces especially, are not held down properly and
> frequently jump with the blade. The blade appears to be moving in a
> straight line and I don't know of any adjustment required here.
> I am just curious if anyone else is having this problem.
>
> Thanks,
> Fritz

The wood "Popping" is normally caused by one or more teeth of the blade
catching on the wall of the kerf on the up stroke. This is a very common
problem with scroll sawyers who are still on the learning curve of the
hobby.

Be aware, that few experienced scroll sawyers use the hold down and
remove the hold down from their saw. That hold down will actually get in
your way as you gain more and more experience. Just hang in there,
things will get better.

The hold down was added to scroll saws sold in North America by safety
regulations. The scroll is one of the safest woodworking power tools;
yes, a very minor cut is possible, but nothing on the scale of a router's
hunger for mangled flesh.

Many newbies (er, I mean, sawyers who haven't obtained expert skill)
apply, inadvertently, sideways pressure during turns and sharp corners.
It is important to develop eye-hand co-ordination which does not deflect
the blade left or right. Ideally, there should be almost no blade
deflection to the rear either, but that is another very long post.

This is my standard advise to newbies:
The cure is to just spend more time just cutting wood. Slow down your
feed rate of the wood on curves, and be aware that on sharp corners you
need to apply more finger pressure (down) to hold the wood tight to the
table. BTW: you are keeping your wrists off the table aren't you? Fore-
arm and back of hand are to be kept in-line, like bowling. No feeding of
the wood with fingers, they only hold the wood down. Swing the wood with
whole arms.

There are web based forums dedicated to scroll sawing where other more
expert opinions can be freely obtained. (just don't take just my word
for it! get a second opinion.)

Forum with large posting membership sponsored by a hobby magazine:
http://www.scrollsawer.com/forum/

There are other scroll sawing forum sites. Post back and I will give you
some more sites. All of them welcome people who join and post
questions. Even lurkers are allowed. Then you can find there are many
who have your same problems, and trust me, there will be more as your
skill level develops.

Good luck, Fritz

Phil

Fritz:

On tight curves, you could be spinning the wood without the blade being
at the center of the spin. Hard to explain with just text typing in this
newsgroup. But as you cut the arc, or tight corner, the blade needs to
be at the dead center, so the teeth have no force to twist. If a
twisting force does happen, then the teeth will catch on the kerf wall of
the metal and a slam pop will occur. A Slam Pop with more force than
your fingers can hold down against. Again, just a problem that can be
solved with practice.

Look around the web, there are scroll saw practice patterns around, or
even puzzle patterns that can be glued to scrap hardboard or cut-off
scraps for practice cutting. Scroll sawing is all about eye-hand co-
ordination moving the wood (metal) past the blade free hand style.

Good luck.

(I am presuming you are using a very high tooth count metal cutting blade
with no skips. And a quality blade at that. Pike jewelry cutting
blades, and Flying Dutchman's metal cutting are two brands of very high
quality metal cutting blades. Just like in Band-sawing, minimum teeth in
contact with the metal is 3 teeth at all times. 1mm aluminum no
exception to 3 teeth rule.)

Phil

First let me say that I am not being a smart ass, as I have made
this mistake myself a few times, make sure the blade is not installed
upside down, it is easy to do with the small teeth of a scroll saw blade.

Second, if the work is really jumping you ma just need to switch to
a blade with more tpi.

The hold downs on scroll saws are just not that effective, they are more
of a safety device to keep your fingers away from the blade. With practice
you will be able to feed at the proper rate and angle to keep the work from
jumping (most of the time...)



--
There are no stupid questions, but there are lots of stupid answers.

Larry Wasserman - Baltimore Maryland - lwasserm(a)sdf. lonestar. org

>> I have an SS350 Delta Scroll Saw. I find that the work tends to jump a
>> lot with this saw. (of course I am using a new blade properly mounted
>> and proper for the stock being cut). I assume that this is caused by the
>> springy nature of the hold down foot? I have bent it a bit to increase
>> the tension and adjusted the extension, close to the work but I still
>> find that thin pieces especially, are not held down properly and
>> frequently jump with the blade. The blade appears to be moving in a
>> straight line and I don't know of any adjustment required here.
>> I am just curious if anyone else is having this problem.
>>
>> Thanks,
>> Fritz

>Be aware, that few experienced scroll sawyers use the hold down and
>remove the hold down from their saw. That hold down will actually get in
>your way as you gain more and more experience. Just hang in there,
>things will get better.
>
>The hold down was added to scroll saws sold in North America by safety
>regulations. The scroll is one of the safest woodworking power tools;
>yes, a very minor cut is possible, but nothing on the scale of a router's
>hunger for mangled flesh.
>
>Phil

I don't consider myself anywhere near being a scroll saw expert, but I
do have a DeWAlt I've been using it for over a year. I removed the
hold down long ago. I keep it nearby but I agree with Phil, that it
just gets in the way. I think I would have given up long ago doing
fret art if I had kept it on.
`Casper