Dimple Dies & Cutting Holes

Greg

Make RME Rockcrawling Again!
Admin
Looking at picking up a dimple die or 2 and using them on the TJ project, mostly for strengthening sheet metal panels that I'll be incorperating into the build. I'm thinking about starting out with one size for now, probably 1.5".

The other part of this is making the hole for the die... what's the best option, a knock out punch? I found a 1.5" step bit... not sure how long it'll last though.
 

Greg

Make RME Rockcrawling Again!
Admin
Found these, I like that it has a bearing built in. I think it would help it last longer.

 

Greg

Make RME Rockcrawling Again!
Admin
I figured a hole saw would make for rough edges... but it's a pretty cheap option. I'm sure the edges could be cleaned up with a flap disc once it was flared.
 

zmotorsports

Hardcore Gearhead
Vendor
Location
West Haven, UT
I started out using hole saws and they worked OK if you made sure to deburr the circumference prior to using the dimple die. Since then I have started using either an annular cutter or knockout style of punch that uses a thread to draw the punch through the receiver. Both of those methods work better than the hole saw but to be honest, the hole saw is the cheapest route and does a fair job.
 

1969honda

Well-Known Member
Supporting Member
Location
Cache
If I remeber right SWAG? or one of the other big vendors does dimple dies that are made specific to knock out punch hole sizes.

Annular cutters are what I prefer for any sheet metal holes. They don't tear up the edges or seem to walk around as much as a hole saw in my experience .
 

Hickey

Burn-barrel enthusiast
Supporting Member
After 70+ dimpled holes in a recent project, I recommend applying grease or lube to your dies. People often don’t since it’s messy, but helps keep the die from sticking in your dimpled part and leaves less marks (if that matters). That’s all I got. 🤷‍♂️
That's a great suggestion. I started lubing mine after a few panels on my trailer build. It is messy, but seems to make the process wear on the dies less.
 

Corban_White

Well-Known Member
Location
Payson, AZ
This is my favorite tool for making holes in sheet metal, but it is just a bit more spendy than other options.

 

Greg

Make RME Rockcrawling Again!
Admin
I ordered one of these from Ali Express for $60... what could go wrong? :D I went for the 1" to try out, will probably get a quality 1.5" dimple die elsewhere.


Well, the 1" knockout & die from Ali Express (China) arrived today, it was $59 with free shipping. The knockout & die came with 2 bolts, which is a good thing. The parts are all heat treated, so hopefully they'll last awhile.

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I was pretty excited, so I found a piece of scrap sheetmetal and started playing around. I drilled a hole with a step bit (about 1/2"), applied Anti-Sieze to the threads and a bit of lube to the die itself, as @Vonski suggested. The piece of scrap wasn't perfectly straight and my layout of the holes wasn't perfectly in line, I was in a hurry and since this was scrap I wasn't too worried about things being perfect.

I grabbed my 1/2" impact and started tightening the bolt, which just threads onto the opposite die. It cut quickly and pressed the sheetmetal in the die relief, but after taking it apart it was obvious that it didn't shear all the way around. I ended up bending the leftover edge back & forth by hand until it came off, then touched up the cut with a flap disc on the grinder.

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I ended up punching 4 holes with the 1" die, then bend the edges up in my little sheetmetal brake. It's amazing how rigid that piece of scrap sheetmetal has become! I really dig playing with the dimple dies, I can see this being a fun tool to integrate into my work. This little piece took me less than an hour to knock out, not bad for my first time using it. Going to add some other sizes to my collection and try different methods to cut the hole.

I feel like over time the threads on the bolt & die might strip out and the cutting edges of the knockout will dull.... they say you can use a press, might try that next. For the price, it's worth considering.

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Greg

Make RME Rockcrawling Again!
Admin
My 1.5" dimple die arrived from Eastwood today, so I rounded up another piece of scrap steel. The Eastwood dies are real nice & heavy duty, look like they'll last a long time. I spent more time laying out the hole spacing, I marked and center punched the intersecting lines where the holes needed to go, to line everything up.

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This time I used a standard 1.5" hole saw with a handheld drill to cut the holes, because it's what I had in the shop. It was a PITA because the hole saw still walked around and the cuts were far from perfect. I spent time with the grinder again and a round file cleaning up the holes. I need to try the annular cutter as @Hickey suggested. I'd like to try cutting the holes on the drill press as well, that should help with keeping the hole saw more centered.

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I think I've decided the best way to cut the holes is with a plasma table.... :eek::thinking:

Drilling out the holes and cleaning them up took quite a bit of time. Once they were ready, I moved to the 20 Ton HF press and cranked out 10 dimples in short order. I'm really happy with this piece, taking the time to layout the holes and spacing makes all the difference.

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Greg

Make RME Rockcrawling Again!
Admin
Just ran across this, could be an easier way? You'd still need to drill the hole to put the centering pin in.



It's too bad the hole sizes are a bit oddball... :(

"Actual hole size (inches) 1.115 in, 1.362 in, 1-11/16 in, 1-15/16 in, 2-3/8 in."
 

Greg

Make RME Rockcrawling Again!
Admin
Picked up a 1.5" annular cutter as @Hickey suggested, it has a 3/4" Weldon shank. Needed to buy a specific chuck for the Wilton drill press to attach the annular cutter, so that's what I did!

The annular cutter was quite a bit smoother than the hole saw for sure, more of a machining bit than a jagged tooth saw. Still, it left some rough edges.... not as bad as the hole saw though. I cleaned up the edges with a wire wheel on the grinder, then a round file.

The annular cutter is a smoother and cleaner option than a hole saw, but the costs are higher... just over $100 for the cutter & chuck. I think it's a better option, next being a plasma table.

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Loaded the sheet metal in the press with the 1.5" dimple dies and cranked out 6 dimples!

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I'm going to have a ton of sheetmetal with dimple dies in them... X-D
 
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