DIYbanter - View Single Post - cutting 1/2" thick aluminum bars on a budget?

JBL

On 06/25/2017 03:35 PM, wrote:
On Sun, 25 Jun 2017 13:56:31 -0400, JBL wrote:

On 06/25/2017 01:45 PM, wrote:
On Sat, 24 Jun 2017 23:13:21 -0400, JBL wrote:

I am attempting to make a few "dovetails" which are brackets used to
attach a telescope to a telescope mount. If purchased outright, for the
kind of dovetails I need, the expense is beyond my budget. I recently
acquired some 1/2" aluminum sheet/ bar. The dovetail needs to be 1.75"
wide at the base, with the sides cut at a 15 degree angle. Length can
vary a bit, but usually about 12-14". My plan was to make at least 3
for the various telescopes I have.

I thought I'd be able to get away with an old circular table saw I had.
Last week, I made some 1/4" thick dovetails of a slightly different
design using my table saw fitted with a plywood blade. This went well,
but when I tried to make these thicker 1/2" dovetails today, I ended up
burning out my saw.

Ideas for a cheap way to make these dovetails would be welcome. I've
been watching Craigslist for another circular to replace the burned out
one, but I don't think it's the best tool for this job without a $30
plus blade made to cut metal and even then I'm not sure it will do it.

Thanks in advance for your help,
John
2 words. Band Saw.

Would you happen to know what size band saw? A neighbor has a 10" saw
with 1/8 to 1/4" blades I could borrow.
How good does the finish need to be? You could use a vertical band saw
but the finish won't be very good, not really good enough for a
sliding fit if that's what you're looking for. But if you just need
the angle for retaining then a bandsaw would be a fast and easy way to
cut the aluminum. You will need to make some sort of fixturing to hold
the aluminum at the correct angle and width. You could also use a
carbide router bit with a rub collar if you have a router. Carbide
router bits are great, they last a very long time compared to the HSS
ones and are not very expensive.
Eric

I just recently picked up a Craftsman router table, but no router yet.
I've never seen a router in use or used one myself and I have started
checking videos on the topic. At some point, I'll pick up a used router.

I suspected the band saw might be a bit problematic for the long angled
cuts I needed unless I added a fence maybe... I'm just going to go with
the carbide blade the others mentioned, go much more slowly and add
small amounts of cutting depth at a time using the table saw. I managed
to find a cheap Craig's List replacement over the weekend. I tried to
salvage the prior saw, but motor windings tested open for continuity and
a replacement motor was far more than I paid for the saw, so just
cheaper to get another used one.