Hardfacing (sort of)...

[Trip59]

Maybe I am trying to picture it in my head and am tired, but do you have an example? You can get different diameter tool steel rods at Fastenal. Do you have to have 3" in diameter? Why? If this is a "drum" rotating, does it really matter as you can put pressure from the top side with bearings to keep things in contact

I'm sure there are tons of these on the market I could buy, but making them is part of the process for me, and the process of making them will yield information and learning to benefit other similar projects where I know there aren't the specific shapes/sizes I need 'off the shelf'

Think about the back of an oven, or washing machine, where there's a dimple to provide clearance for a screw head. Nothing fancy, pretty simple.

This is for a product I hope to start producing soon, but other products in the works will need specific and custom sizes I may not be able to find, so this first round is sort of a prototype in and of itself.

Bottom die will be static, steel located on a pin, upper die locate on same pin, attached to the ram of the press. Apply pressure, release and done. Striking would be more ideal, but the press will work well enough for what I'm doing.

[Rambozo]

I'm sure there are tons of these on the market I could buy, but making them is part of the process for me, and the process of making them will yield information and learning to benefit other similar projects where I know there aren't the specific shapes/sizes I need 'off the shelf'

Think about the back of an oven, or washing machine, where there's a dimple to provide clearance for a screw head. Nothing fancy, pretty simple.

This is for a product I hope to start producing soon, but other products in the works will need specific and custom sizes I may not be able to find, so this first round is sort of a prototype in and of itself.

Bottom die will be static, steel located on a pin, upper die locate on same pin, attached to the ram of the press. Apply pressure, release and done. Striking would be more ideal, but the press will work well enough for what I'm doing.

I made a similar punch and die to make rectangular dimples in stainless sheet (about 14-16 ga. as I recall) for heat riser block off plates for Oldsmobile V8s. The punch and die was just mild steel and used a small air over hydraulic piston pin press for power. Made a metric assload of those little plates and never had a problem with the tooling. If you don't go crazy with the pressure and have the proper clearance and edge radius on everything you should be fine. If you want to have your tooling punch the hole as well, you can always machine a place to install a commercial punch and die set in the middle of your dimple punch. Then it will be easy to replace just that part when it gets dull.

[Trip59]

I made a similar punch and die to make rectangular dimples in stainless sheet (about 14-16 ga. as I recall) for heat riser block off plates for Oldsmobile V8s. The punch and die was just mild steel and used a small air over hydraulic piston pin press for power. Made a metric assload of those little plates and never had a problem with the tooling. If you don't go crazy with the pressure and have the proper clearance and edge radius on everything you should be fine. If you want to have your tooling punch the hole as well, you can always machine a place to install a commercial punch and die set in the middle of your dimple punch. Then it will be easy to replace just that part when it gets dull.

Wow, ok. So you did nothing to the tooling, no facing, treating, anything else? Not sure if I'll reach a metric assload, or even an imperial assload, but there will be quite a few for sure if all goes as planned.

As far as the punching, I hadn't really thought about incorporating a punch and die, but drilling them shouldn't be too bad, simple jig and clamps and I can run through a stack at once, pre-braking, then set them up and press them after braking to shape.

Question, how many tons was the press you used?

[Rambozo]

Wow, ok. So you did nothing to the tooling, no facing, treating, anything else? Not sure if I'll reach a metric assload, or even an imperial assload, but there will be quite a few for sure if all goes as planned.

As far as the punching, I hadn't really thought about incorporating a punch and die, but drilling them shouldn't be too bad, simple jig and clamps and I can run through a stack at once, pre-braking, then set them up and press them after braking to shape.

Question, how many tons was the press you used?

For sheet metal if at all possible I would punch the hole rather than drill it. Getting a burr free hole in sheetmetal with a drill doesn't happen, and it's worse when you drill a stack. You will spend more time and aggravation deburring before the next step. Stainless leaves tough burrs. What size hole do you need? If you have the hole in and can run on a center pin, that will make alignment easy, if your dimple is circular. I had two pins for alignment but a pretty loose fit and no springs, because of the kind of press I was using. The press was an old piston wrist pin press that was retired when we switched to a rod heater for installing wrist pins. There were no labels left on it, and a quick search didn't turn up anything that looked like it. I'm sure it wasn't much considering the way it was made, figure max 10 tons, and probably a lot less. For this job it barely had to work, I would even say you could do it with a good arbor press. The pressure you will need depends on how much deformation your are looking for and how much you need to stretch the metal. If you can avoid sharp edges and steep walls, it will be easy to press and come out looking much nicer.

[cbmkr]

We used a lot of small one off dies for 16-22 ga sheet metal and used 1018,1044,1045 cold rolled steel to make the dies, on the smaller dies that got a lot of hard use forming hot rolled structural steel we had some of them sent out and had them heat treated just to give them some added protection. On our larger dies for our 12' press brake we used 1018 cold rolled to build stamping dies, one was 2" x 1" half round cold rolled bar attached to a piece of 3/4" x 4" wide 1018 flat bar, this produced a half round dimple 2" wide and 1" deep in 16 ga sheet steel 48-72" wide to produce grain bed and trailer sides. We also did the same for Dump Truck Beds stamping a 2" angle form into the sides in 7-10 ga sheet, a lot of these were 12' long. Our radius dies for our bed floors were made from DOM tubing in 2,3, and 4" radius sizes.The floor dies did 10 ga to 1/4" all made in house from cold rolled products.These larger dies were in use in our shop for approx 8 years before we sold our company without any problems or adverse wear.