Made my own dimple die...and it actually works!

Graham08 · #1 11-22-2008, 08:07 PM

I was reading one of Ron Fournier's books the other night, and it mentions that flaring dies (at the time it was written) are typically homemade but very useful. I'm in the process of mounting a fuel tank in a supermodified, and some of the tabs were screaming for dimples, and my tool budget is currently zero, so I decided to give making one a shot.

I decided on a 3/4" die, and made the OD 1-1/8". I was fiddling around with a circle template on paper, and it seems like adding about half the diameter of the hole to be flared makes them look right...so a 1" hole would end up with a 1-1/2" OD flare, 1-1/4" would be 1-7/8", and so on.

I made the OD of the die 1-1/2". Mostly because I had a chunk of 1-1/2" 4130 bar in the shop, but this also seemed to give a nice flat to flatten the sheet back out.

My flare angle is 35 degrees. This I borrowed from the Mittler Bros. aircraft style flares.

The biggest question I had was the clearance...If you make the OD of the flare the same on the male and female dies, it will pinch the sheet, making a big stress riser. That seems to defeat the purpose of dimples, so I actually fired up the computer to lay it out. Because I was planning to do 16 gauge (0.063") sheet, that's what I made my clearance for. This resulted in the OD of the flare on the male die being 1.054". I arrived at this from a drafting layout where I offset the angled part of the female flare by the sheet thickness, and measured the ID.

So here is the resulting die set after about half an hour of fiddling on the lathe...

I made the male die with a 1/2" hole down the center. This is so I could use a 1/2" bolt to squeeze them...I don't have a press just yet.

And here is a sample flare...

And finally, this is the piece that prompted the whole thing. Material is 16 ga (0.063") normalized 4130 sheet. I'm going to start a thread on this in the racecar fabrication forum once it's done.

I'm pretty psyched about the results. So much so I figure on making some more of them in other sizes. It's definitely not rocket science, and I wish I had done this a long time ago. Granted, my die isn't as nice as the Light Racing version, and not heat treated, but I have all of about $1 worth of bar stock and some time invested.

So, if you have access to a lathe and some time, it's definitely worth a shot to make these.

jungle · #2 11-22-2008, 09:15 PM

Nice job!!
You got me thinking now!!

Mopars 4 Life · #3 11-22-2008, 11:21 PM

Yeah no doubt..I've been wantin to make some but I prolly need to get the press mounted first huh??

Good job and keep it up.....

Ladderbar · #4 11-22-2008, 11:35 PM

nice

TheBandit · #5 11-23-2008, 12:51 AM

Nice work. Glad to see someone making their own. Even without hardening, I imagine they'd last quite a while.

Gearhead61 · #6 11-23-2008, 03:38 AM

probably wouldn't cost much to heat treat them once you make them so they last even longer!

putter · #7 11-23-2008, 12:47 PM

That's great!!! The best part of the whole deal is you didn't buy the Light Racing MADE IN CHINA ones like I did.
Putter

Captainfab · #8 11-23-2008, 06:13 PM

Quote:

Originally Posted by putter

That's great!!! The best part of the whole deal is you didn't buy the Light Racing MADE IN CHINA ones like I did.
Putter

WTF? When did they start that? I assumed that the ones I bought a couple years ago were made in the good 'ol USA.

Nice work Graham08!

rharriman · #9 11-23-2008, 06:15 PM

Nice work and great job on the machining. I would recommend about 5 min with some emory cloth on the lathe and some scotch bright to polish them up nice. Then heat treat and they will lost along time.

patooyee · #10 11-23-2008, 11:00 PM

You inspired me to try making my own so i went to the shop tonight and knocked one out on the lathe. I only had big enough material for 1/2" die but it works good. It took long enough to where I'm not going to bother with any more though. I am addicte dnow though. I'll be buying a set for my next buggy.

J. J.

finelinefab · #11 11-23-2008, 11:03 PM

nice job well done

Graham08 · #12 11-24-2008, 09:16 AM

Thanks guys!

I didn't realize Light Racing was sourcing their stuff offshore. I'm glad I decided to make my own right here in Ohio.

I plan on polishing them a little better. I was anxious to see if it worked first before putting much time into it. The surface finish doesn't seem to make a difference on 4130 sheet, but I also want to use it on Al, and I can't stand scratches.

Dqracer · #13 11-24-2008, 10:09 AM

Very nice..! I'm gonna have to find the time to whittle me out a set of those, are you still gonna do a build post on them..?

Graham08 · #14 11-24-2008, 12:51 PM

Actually I was going to do a build thread on mounting this fuel cell, which is what the pic is of in the first thread (plate with 7 dimples in it)...I can do a thread the next time I go to make one of these, but there really isn't that much to it once you have some dimensions to go off of. The female die is really easy, and the male isn't much more difficult.

patooyee · #15 11-25-2008, 10:09 AM

I'm quesitoning the time it took me to make my one little one vs. just buying a set. I had about 2 hours into my 1/2" one but I started with stock that was a little too big because its all I had laying around. I was also in a hurry to knock it out and test it so I didn't get the surface finish I wanted. That would have taken even longer. BIgger died would take mroe time so I could easily see having 15+ hours into a set of 5 and then I'd still want to heat treat them to make them last longer which would add more expense and time. You can get one of the Chinese sets for under $200 I think and a decent American set of 5 for around $300. I don't see why being made in China is so bad. IMO Amercan quality has become an oxymoron and I live in a global economy, not a local one. This is a solid chunk of steel with minimal machinning and light tolerances. The Chinese don't do it by hand either, they use CNC machines just as we would. Either one of those options are worth 15 hours of my time personally.

Now I do have some friends who have access to some CNC centers. If one of them will commit to making some I will just draw them up in Solidworks and have them cut that way.

J. J.

patooyee · #16 11-25-2008, 10:14 AM

Does anyone have a link to the Lite Racing dies? I can't seem to find them ...

J. J.

Graham08 · #17 11-25-2008, 11:02 AM

Check out Keith's site...it's linked from the main page. He has the best prices I have seen on the Light Racing version. These are the ones discussed above that are currently being machined offshore, and are about $300 for a set of five. They are a very good piece...I think all of the stuff in the mega Flared Hole die thread were made with them.

My only point was if a guy was so inclined, they can be made with good results, and it wasn't as difficult as I thought it would be.

Dqracer · #18 11-25-2008, 12:58 PM

Doing it yer self gives ya pride of ownership ,ya know it was done right,(ya hope) it's made in America, an' ya can't cuss out the chinese if it falls apart .

jungle · #19 11-25-2008, 03:20 PM

How much larger are you making the female side of the angle compared to the male side. I know you are building to a 35Deg angle & for .063 stock.
Thanks!

Graham08 · #20 11-25-2008, 04:05 PM

The OD of the flare on the female side of the die was 1.125", the male was 1.054"...within a few thou. Both ID's are 0.750". I don't think it is super critical, just that you don't pinch the sheet too much.