I have some hand tools, but no significant shop tools.
A long-standing problem... Sometimes aluminum flat bar is bent
into a U shape so that it can be used as a wheel axle. The problem
is drilling holes through each fork so that they line up
perfectly. I don't trust my cheap drill press. But... The distance
from one fork to another, the inner width of the fork is known and
will be the same the next time, so a mold might be useful.
It would look like a 2 inch piece of 1x1 wood with a 1/4 inch hole
drilled through the center on one side. Except that it needs to be
about 1 1/8 inches wide (for the fork width, to fit between the
fork). And if it's made of wood, it would need an aluminum or
steel insert/sleeve so that the hole does not widen when used.
I have a belt sander and a caliper that can be used to produce a
well dimensioned rectangular block of wood. And then, with some
repetitive manipulation, maybe my cheap drill press would help
drill a perfectly perpendicular hole through the wood.
But I'm thinking maybe something store-bought would do. Something
that has a hole in it. For example... If I could get a hold of
some large diameter 1/4 inch washers that are perfectly made, I
could stack them one on top of the other. Then stick the drill bit
down through the hole in one fork and through the stack of
washers. Then clamp the fork down on the washers (on both sides).
Actually, I guess that wouldn't work unless the washers were
perfectly the same inner diameter as the drill bit. Or maybe if
they were very thick washers.
Hopefully at least my question is clear enough. If not, I am happy
to explain what I'm trying to do.
Thanks.
Good luck finding well made washers these days, the ones around here
are all sorts of thicknesses and often have big chunks out of the
edges.
Lee Valley sell these, which should help:
http://www.leevalley.com/US/wood/page.aspx?p=40089&cat=1,180,40089
But you probably want to make your jig so the aluminum goes into a
slot, with the bushing on top.
regards
Bruce
Another option:
If you need a jig for drilling a hole in multiple aluminum axle
frames, you might have a local machinist or trade school student make
a jig with a 1X1X2 metal block. They can accurately drill the guide
hole and it would likely not cost too much to make such a jig.
The trade school students, here, appreciate a nice gratuity for small
projects, as that, and the instructor encourages the students to take
on some practical projects, as that.... same with the welding
department students/instructor. I occassionally have a project for
both departments. For the machinist students, the instructor asks
that I supply an accurate drawing, a set of precise plans, for the
students to follow, rather than word-of-mouth type instructions.
I like to try making my own jigs, though, so this may be your
approach, also.
Sonny
John Doe wrote:
> I have some hand tools, but no significant shop tools.
>
> A long-standing problem... Sometimes aluminum flat bar is bent
> into a U shape so that it can be used as a wheel axle.
One of these would serve as the middle bit of your jig:
<http://www.grainger.com/Grainger/hex-standoffs/spacers-and-standoffs/fasteners/ecatalog/N-8niZ1z0o4bfZ1z0o4o3>
A welder and hack saw and a piece of flat bar would work well.
--Winston
"John Doe" <[email protected]> wrote in message
news:[email protected]...
>I have some hand tools, but no significant shop tools.
>
> A long-standing problem... Sometimes aluminum flat bar is bent
> into a U shape so that it can be used as a wheel axle. The problem
> is drilling holes through each fork so that they line up
> perfectly. I don't trust my cheap drill press. But... The distance
> from one fork to another, the inner width of the fork is known and
> will be the same the next time, so a mold might be useful.
>
The oldtimer trick was to attach an upward-facing point to the drill
press table directly in line with the spindle to locate the punch mark
or pilot hole on the lower end of the work, while you drill the upper
end. Then your problem becomes accurately marking the hole positions,
which can be done with inexpensive hand tools
You can grind and file the point on a short piece of threaded rod
chucked in the drill press.
To position it on the spindle centerline, UNPLUG the drill press,
chuck a piece of stiff wire that nearly reaches the table and
straighten it so the lower end makes the smallest possible circle when
you turn the spindle by hand.
These are better:
http://littlemachineshop.com/Reference/Wiggler.php
jsw
"John Doe" <[email protected]> wrote in message
news:[email protected]...
>I have some hand tools, but no significant shop tools.
>
I had no proper metalworking machines as a kid, but we did have an old
cast-iron Shopsmith which turned out to be very useful for making
pre-industrial-type machine parts from wood, plastic and aluminum. It
could be set up as a horizontal boring machine to drill frames for
shafts, like this problem.
jsw
On 3/24/12 10:51 PM, John Doe wrote:
> I have some hand tools, but no significant shop tools.
>
> A long-standing problem... Sometimes aluminum flat bar is bent
> into a U shape so that it can be used as a wheel axle. The problem
> is drilling holes through each fork so that they line up
> perfectly. I don't trust my cheap drill press. But... The distance
> from one fork to another, the inner width of the fork is known and
> will be the same the next time, so a mold might be useful.
>
> It would look like a 2 inch piece of 1x1 wood with a 1/4 inch hole
> drilled through the center on one side. Except that it needs to be
> about 1 1/8 inches wide (for the fork width, to fit between the
> fork). And if it's made of wood, it would need an aluminum or
> steel insert/sleeve so that the hole does not widen when used.
>
> I have a belt sander and a caliper that can be used to produce a
> well dimensioned rectangular block of wood. And then, with some
> repetitive manipulation, maybe my cheap drill press would help
> drill a perfectly perpendicular hole through the wood.
>
> But I'm thinking maybe something store-bought would do. Something
> that has a hole in it. For example... If I could get a hold of
> some large diameter 1/4 inch washers that are perfectly made, I
> could stack them one on top of the other. Then stick the drill bit
> down through the hole in one fork and through the stack of
> washers. Then clamp the fork down on the washers (on both sides).
> Actually, I guess that wouldn't work unless the washers were
> perfectly the same inner diameter as the drill bit. Or maybe if
> they were very thick washers.
>
> Hopefully at least my question is clear enough. If not, I am happy
> to explain what I'm trying to do.
>
> Thanks.
What about using a piece of pipe as a drill guide? Or a pipe
like machined bushing? Metal sleeve might be a better term. The
internal diameter would have to be just a bit larger than the drill bit
size.
Drill the first hole then use the bit to help line up the sleeve.