Where do you guys get your metal knockout hole punches?

[culturejam]

I did a bit of searching here, and I see several references to using punches in chassis fabrication. But I don't see references to brand names, etc, or sources for the punches themselves.

I see Greenlee has a cheap kit with at least one or two useable punch sizes (7/8"is the smallest hole size). What about smaller holes? Are there punches for these, or do you guys just drill for all holes smaller than 7/8"??

I have a step bit and a drill press, but I think punches would be nicer to work with.

Thanks

[Structo]

For aluminum you can drill pretty easily.

But, if you can afford the expensive Greenlee punches then by all means, buy them and use them.
They most likely will leave a cleaner hole than a drill.

[culturejam]

Harbor Freight has something almost the same for $25:
http://www.harborfreight.com/cpi/ctaf/d ... mber=91201

The issue is that the punch/die for the 1/2" conduit makes a 7/8" hole, and that's the smallest hole size.

[smolder]

Harbor Freight has something almost the same for $25:
http://www.harborfreight.com/cpi/ctaf/d ... mber=91201

The issue is that the punch/die for the 1/2" conduit makes a 7/8" hole, and that's the smallest hole size.

I just bought the harbor freight punches. They work fairly well and really well for the price. But be advised... the sizes listed are for holes [Includes punches and dies for 1/2", 3/4", 1" and 1-1/4" pipe and conduit, in a blow mold case] that will accommodate that size plumbing pipes. Ultimately, the holes are larger than that size.

[culturejam]

But be advised... the sizes listed are for holes [Includes punches and dies for 1/2", 3/4", 1" and 1-1/4" pipe and conduit, in a blow mold case] that will accommodate that size plumbing pipes. Ultimately, the holes are larger than that size.

Exactly. A 1/2" conduit needs a 7/8" hole.

The Greenlee catalog lists a few sizes of die/punch that make holes smaller than 7/8, but they're not exactly standard sizes. Hmmmm.

[tubeswell]

I have a range of chassis hole punches from 1-1/8", 1", 7/8", 3/4", 1/2"

I got some of them at a dandy little local 2nd-hand tool shop and others from an engineering supply wholesaler

[M Fowler]

I have greenlee from an wholesale electrical distributor. But Allynmey sells them on his website.

I use Harbor Freight step drills most things though.

[smolder]

I have greenlee from an wholesale electrical distributor. But Allynmey sells them on his website.

I use Harbor Freight step drills most things though.

those are cool. How do they work? I find the punches distort the metal just a bit. Not super clean, but neither are most hand drills (I really need a press I guess)

[glasman]

Mouser has a line of english and metric size punches by Deltron. Not as nice as Greenlee, but still very servicable and about 1/2 the price.

[gearhead]

I've used a couple of Greenlee stepper drill bits with pretty good results. The Greenlee's are double fluted, meaning they have two cutting surfaces. Supposedly faster and with cleaner holes than single fluted. Don't have any singles for comparison, but they killed my interest in getting punches.

[culturejam]

Thanks for the tips, everyone!

[M Fowler]

I found that by the time I drilled that large hole for the punch stud I could just as well drill the rest of the hole with the step bit.

I have to admit I use my step bits the most and have them in many different sizes from Harbor Freight.

A clean step bit works really nice on the wood face plates like the ones I get from Distortions, his trick.

Mark

[culturejam]

I found that by the time I drilled that large hole for the punch stud I could just as well drill the rest of the hole with the step bit.

This is a great point. For everything besides the tube socket holes, I'll just pilot hole > step bit. But I do like the way the punch works for the 7/8" and 1" holes. The less clamping and flying hot metal, the better.

I picked up a Greenlee 7/8" from Lowes on Tuesday afternoon, and I have a 1" on order from Mouser.