Aluminum plate round

I seek the mind of the hive. . .
Does anyone have (useful) suggestions on how to cut a rectangular piece
of 3/8 inch aluminum plate into a 90mm round?
The tools I have available are a big drill press, vise, hacksaw and
grinder. I don't want to have a center hole, so cutting it roughly to
shape and using the drill press or grinder to finish the circle is out,
unless there is some sort of super suction cup available.
Thanks for any help.
Reply to
Ted Bennett
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--Sounds like the best "tool" you could use about now is a neighbor with a complete shop! Got any pals who fit that description??
Reply to
steamer
I would do it in my wood cutting band saw with any wood blade up to about 1/2" wide, but then, I have the band saw. Gerry :-)} London, Canada
Reply to
Gerald Miller
It is amazing what purchasing/trading power the 12-pack of common swill can have.
michael
Reply to
michael
Hmm...sounds like me (only I haven't had a use for a big aluminum disk, and if I ever did I'd probably cast it). :-)
First idea would be a fly cutter type hole saw in the drill press, but that needs a centering hole. If it's a nice and stiff 'press you might be able to get away with one specially made so it centers from the chuck instead of the work...but I'm probably suggesting major injuries here so let's move on.
My practical idea is to scribe/draw a circle on the plate (you don't mind a centerpunch mark in the center do you?) and run around it with a scroll saw.. if you don't have one of those you might get away with the hacksaw, if you can't steer the cut fast enough then you can cut corners until you've had enough. In either case, cut oversized and finish up with a file. Don't use the grinder unless you have a wheel made for aluminum.
If I had a lathe I might part off a 3/8" slice of 3 1/2" round. ;)
Tim
-- In the immortal words of Ned Flanders: "No foot longs!" Website @
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Reply to
Tim Williams
1. Since you're asking machinists (mostly), our first question is: what tolerance? I.e., 90 mm plus or minus what? Or, if you can tell us what this will be used for.
2. What is your budget for new tools?
3. If the answer to "1" is "+- 1/16" and "2" is "$15 - $20", then a 3 1/2" hole saw for your drill press will work. Clamp the stock & remove the center drill.
Bob
Reply to
Bob Engelhardt
Hacksaw to a rough hex or octagon shape and BELT sand to a scribed circle. Do not use a grinder with out a special Al wheel ($$) or you will quickly load it up beyond use. Don Warner
Reply to
Don Warner
double face tape it to a piece of plywood with a center in it for the drill press and go at it with the grinder
Reply to
Dan Petroski
Simply draw the circle and hacksaw to the line.
This should take about 15 minutes.
Jim
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Reply to
jim rozen
In 3/8" plate?? You're a better man than I, Gunga Din. :-)
Ted
Reply to
Ted Edwards
Do you do this sort of stuff often? Would/could you use this as the long awaited excuse to buy a lathe or 3-in-1?
Can't see doing this on a drill press but given that I have a Smithy 3-in-1, I would draw the circle and rough cut out the disk leaving as little as convenient outside the line. I would then cut out a piece of (say) 3/4" MDF (Medite) in a rough disk a little smaller than 90mm diameter and stick this on the faceplate, reasonably centered, with double sided tape. I would then place some more double sided tape on the MDF and use a center in the tailstock to gently position the work piece on the MDF well centered. I would then replace the center with something with a flat surface in a live center to press firmly against the work piece and thus keep it from slipping. I could then turn the OD of the disk to 90mm to whatever tolerance is required. The MDF will allow you to get at the entire 3/8" of the piece.
If a small pip in the center is to be avoided, a piece of electrical tape could be used for one leg of the dividers when drawing the circle and for the point of the center when positioning the work in the lathe.
As I said, I can't see this working in a drill press.
Ted
Reply to
Ted Edwards
This isn't that kind of problem. Years ago, before I had many machine tools, I cut a disc out 3/8" aluminum for a thedolite base. I used a coping saw with a file to clean up the edges. Didn't take that long. While this is an excellent excuse to buy a milling machine, don't let a lack of one prevent you from making what you want.
Kevin Gallimore
Reply to
axolotl
Around 3/4 linear inch per minute in 3/8" aluminum? Sounds aboot right to me, given the right blade, sharp and turned the right way around.
Best regards, Spehro Pefhany
Reply to
Spehro Pefhany
1) use a fairly coarse blade.
2) wd-40 for cutting fluid
I just got done cutting out a wrench, out of 3/16 thick CRS plate, about 12 inches long, with each end being a 2.5 inch circle. The body between them was about an inch across, so it meant cutting along most of the length.
I was going to take it to work and use the bandsaw there, but figured hey, how long could it take with a good blade on a hacksaw. Answer: about 15 minutes all told.
I did however use the *big* pedestal grinder, and the belt sander, at work, to round off the ends.
Jim
================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================
Reply to
jim rozen
Thanks for that link, Jim, but they don't list anything that looks like it would be a drop-in replacement for my bike (which comes with something called a Wagner 4467).
I will contact Candlepower and see if they can come up with something.
Reply to
Ted Bennett
Holy cow, what is it, a chushman scooter?
Jim
================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================
Reply to
jim rozen
Rozen sez, blatantly showing his age: "Holy cow, what is it, a chushman scooter?"
BS
Bennett
Reply to
Bob Swinney
Use a router. Make template. Multiple passes with straight cutting bit. Spiral upcut router bit from Hartlauer.
Reply to
dann mann
you can cut or grind down your hacksaw blade narrower so you can make the corner.
Dave
Reply to
David L Peterson

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