hole saw for aluminium heat shield

15mm and 25mm. I want to shape them into a pattern, a sort of design, so I think that NormanE's suggestion of using my bench press drill with some decent saws and some lube into a aluminium and ply sandwich is my present objective. The heat shield is not very big 740mm by 340. The only key dimensions are fixing screws on the L and R edges.
 
I'll
15mm and 25mm. I want to shape them into a pattern, a sort of design, so I think that NormanE's suggestion of using my bench press drill with some decent saws and some lube into a aluminium and ply sandwich is my present objective. The heat shield is not very big 740mm by 340. The only key dimensions are fixing screws on the L and R edges.
I'll have a look and see what I've got.
 
Reminds me of the joke about outback Australians. "Australia where men are men and sheep are nervous" or I only have eyes for ewe.

Ye-e-e-s. I'll make the cannonballs; you fire 'em.......

At least you didn't inquire about his 'Boknaai boots'.
 
The problem with hole saws is there no way out for the swarf/sawdust. It stays trapped in the cut and gets hot ... then buggers the saw.

I get a vacuum cleaner and suck the swarf out the cut as it forms..
Alternatively I cut a couple of escape holes on the inside of the cut ring to allow the swarf to collect there.
 
Pretty small holes, so less trouble.
One thing, esp if using the centre drill is problematical, first drill a hole in a bit of wood, then clamp that into the ally to guide the saw. I usually lube, even in ally.
DW
 
Hi

An alternative to using hole saws in aluminium sheet would be 'blacksmiths' drill bits, they provide the larger hole size but have reduced shanks so they fit standard drill chucks. May give a cleaner hole than hole saws.
 
The problem with hole saws is there no way out for the swarf/sawdust. It stays trapped in the cut and gets hot ... then buggers the saw.

I get a vacuum cleaner and suck the swarf out the cut as it forms..
Alternatively I cut a couple of escape holes on the inside of the cut ring to allow the swarf to collect there.

That true but the aluminium is only 2 mm thick. Also if the swalf dose build up just withdrawing the saw will clear the swalf from saw.
 
15mm and 25mm. I want to shape them into a pattern, a sort of design, so I think that NormanE's suggestion of using my bench press drill with some decent saws and some lube into a aluminium and ply sandwich is my present objective. The heat shield is not very big 740mm by 340. The only key dimensions are fixing screws on the L and R edges.

Is it still going to work as a heat shield after you've drilled all these holes?
 
I guess you've never tried large twist drills on thin sheet?

I'm assuming the sheet can be placed on a block of wood underneath it, in much the same way that it would help with a hole saw,
I have found that both large twist drills and hole saws can be a real pain on thin materials unless well supported underneath, but I would agree maybe a hole saw Is a better option.
 
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A note of caution for anyone reading this who may be going to drill larger holes with a hand held drill. On breakthrough hole saws can suddenly bind and the drill itself may then wrench your hand/wrist. Make sure the workpiece is held securely and you are ready for a jolt. -or better still use a pillar drill or similar.
 
Noted Halo, thanks.

Using a pillar drill, plus clamps.


However the project is on at least week's delay so no pictures of WIP or swarf all over the place etc. Apparently the house kitchen lights need replacing. All of them. Tut, domestic priorities...
 
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