Making solid metal dishing forms

[William of Stonebridge]

OK I have made dishing stumps out of wood. I know there has been many that have made dishing forms from the ends of tanks. I have seen dishing forms cast from ductile iron.

However, I do not recall ever seeing a dishing form made from a solid piece of steel. I thought a solid dishing form might ring less than one made from a tank and maybe be more sturdy and efficient due to the extra mass. I plan to use it to dish hot.

Would there be any problems with using a solid dishing form made from scrap mild steel? Would it be possible to put a 8" diameter by 3" high piece of steel in a lathe to cut the bowl? Any advantages/disadvantages? Has anyone done this?

[HammerHand]

The best thing you could probably do to have one made is ask a local metal shop if they have a CNC machine that is able to dish out a cube of steel. It's the same machine that they use to cut the wheels for cars and motorcycles out of aluminum blocks. I do not know if a lathe would suffice for what you are attempting to do. You could also take the bottom of a scrapped tank of oxygen and if you have a way to SAFELY heat lead and have enough lead, flip it over and pour your own mold. It won't be steel, but it will be solid and ring less. Good luck!

[The Iron Dwarf]

most of the people I know are happy with the bottom of bottles, mind you I have sold some that have been an inch and a half thick and I also have an oval dishing donut that is about head sized and over 2" thick but between us there is a little water and shipping costs are quite a bit

[Armourkris]

I made my metal dishing form by welding a sheet of 3/16" steel over some 4" thick walled pipe, then i heated it up good and hot and bashed it into a dish with my shot-put-on-a-stick. afterward I poured a bunch of molten ead into the base.

It worked good and didn't really ring at all, until the hunk of lead broke free and fell out the bottom. now I use the lead dish and use the steel one as a mold when i need to re-cast it.

not sure if any of that helps, but that's my experience with a lead filled "solid" metal dish.

[schreiber]

I don't think there's much that the ductile iron dishes won't do for you.
Ironmonger just got a new foundry lined up and had ample supply of them at Pennsic two months ago.

I'm pretty sure the reason you see ductile iron used is because it is much less prone to fracture than cast iron, and the melting point is still comparatively low - around 2100F. You can do that with a forced-air propane foundry.

Casting certainly seems to be the way to go. I think if you spec out what it will cost to have something like that turned, you'd probably take that amount of money and buy a full set of Ironmonger's forms, plus a stake plate and 3 or more stakes to go in it. ie, it's not going to be cheap unless you know someone. Just getting rods faced is expensive - anything involving a bowl is technically difficult for a machinist to do just once.

Something I've thought about for a while is the possibility of forging dishes, say by heating up a 1/2" round plate and dishing it against an anvil. But that'd take a serious forge, and probably a couple sets of hands.

[losthelm]

Production time on a lathe with a skilled machinist makes these expencive. I know they make jigs for tapers and radius sized for lathes but finding one for a hobby lathe takes time.
With a CNC its much cheaper once the program is written but still not cheap for a single piece.

The bottom of high presure tanks are much cheaper. you can pack them with lead or sand to deaden the ring and weld a cap/mounting plate to the bottom usualy 3/16" works well.

If your working cold low temp metals are deffinatly the way to go.
aluminum is cheap and easy, lead tire weights are cheap but you have to seperate the steel clips, steel or iron alloys take a much higher temp and usualy special equipment. I have sceen it done, but the results usualy take a bit more cleanup then lead or aluminum.

[The Iron Dwarf]

Something I've thought about for a while is the possibility of forging dishes, say by heating up a 1/2" round plate and dishing it against an anvil. But that'd take a serious forge, and probably a couple sets of hands.

I was thinking along the same lines a while ago by getting a plate hot and using my press to form it ( of course it helps if you have 4", 6" and 8" hardened and polished ball bearings )

[Brennainn]

Where do you buy your bottle bottoms?
Thanks,
Brennainn

[Keegan Ingrassia]

Where do you buy your bottle bottoms?
Thanks,
Brennainn

Local welding supply store with an oxy-acetaline refilling area in the back. Occasionally they get a bottle that is too old/worn out/damaged to be refilled.

While you're at it, you could also get different lengths of the tube, to turn into effective stakes for gutter forms. I find a 5" piece more versatile than a 1' piece, though.

While we're on tubes, see if there's a local business nearby that makes drill stem pipe. Stuff is thick-walled, hard, and excellent for a variety of things.

[The Iron Dwarf]

never cut an acetalene bottle and be very cautious with any fuel gases

[Brennainn]

Just to say,
I bought a form from Halbreds. It is awesome.
Thanks,
Brennainn

[Halberds]

MY first dishing form was made on a large CNC lathe from 6" dia, 1018 solid bar stock.

Shown here with my 6" dome also CNC machined:


The draw back is that it only has one radius.
I prefer the doughnut... as I can achieve any radius to suit my needs.
Helm halvs or elbows in the same dish.

Hal

[Thomas Powers]

Fellow at quad-state had a pile of tank bottoms for sale, $10 a piece as I recall.

A friend had a set of solid steel dishes made that used no machining---did it with high explosive and so a 6" thick round has a nice smooth dish in it...Handy to have an explosives research center on campus sometimes!

Thomas

[Brennainn]

So someone in Soccorro has tank bottoms for sale?
Thanks,
Brennainn

[losthelm]

Quad state is a blacksmithing gold mine for tools Its in troy Ohio.


Some welding supply shops will not sell them because of problems with folks trying to repair and recycle the tanks.

Co2 helium, O2 and other inert gas tanks are preferable.

propane tanks are thin and propolean or acetalean have a fiber matrix thats not worth dealing with.

The propane tanks work well for building protable forgers and small fire pits.

[Chretien le Meunier]

The best thing you could probably do to have one made is ask a local metal shop if they have a CNC machine that is able to dish out a cube of steel. It's the same machine that they use to cut the wheels for cars and motorcycles out of aluminum blocks. I do not know if a lathe would suffice for what you are attempting to do. You could also take the bottom of a scrapped tank of oxygen and if you have a way to SAFELY heat lead and have enough lead, flip it over and pour your own mold. It won't be steel, but it will be solid and ring less. Good luck!

Lathe would do the job, using a 4-jawed chuck and proper tooling (progressively roughing out the dish with 55 and/or 35 degree stick tools, oriented in a facing position, then move onto a bore bar)

As someone stated as well, the CNC would be the way to go, but the set-up time would'nt make it cost effective, unless doing a largish run.

That all said, I am looking to build a home CNC to compliment my manual machines in my home shop, I have a mental list of SCA useful things to produce out in the shop, and this item is now added to that as well. Great idea.

[Armoured Air Bear]

I was very close to getting an anvil that had swages on each side of it. by swages I mean a very large and deep oval dish. this would have been ideal for armouring, especially while hot working the plate.

However, Fred got that one too...

[sha-ul]

I have been kicking around the idea of making some sort of armourers swage block, take a cube of solid steel, probably cast, with an out side measurement of say 6", within that place dished faces of different depths of 5" that would provide a little extra meat around the edges to prevent a fracture.


I know we have some very talented Engineers& retired Engineers here that could probably design this to be cast up at a small foundry like what the saltfork blacksmithing club of OK. did, made their own design, then arranged for a production run

[Thomas Powers]

I believe that the salt fork blocks are "These swage blocks are new castings from a good grade of cast iron."

Heck of a cost difference between casting cast iron and casting steel!

When we did a forge building workshop using O2, N2, CO2, Ar, etc tanks that failed hydrotest the test co gave us the tanks for free as long as we cut them up onsite---shoot they even provided the gas all we needed was the torch. Filled 3 pickups with tank pieces as I recall.

Also at Quad-State I saw some of the pintle and ring hitch toroids converted intop dishing rings.

B; as I was given 7 tanks a couple of years ago near Santa Fe; I have not dug into local sources but may be able to turn loose of one of my stash. When are you going to come down and visit?

BTW places that do fire extinguisher maintenance often have old CO2 tanks with interesting bases. (CO2 as then you don't have to worry about the toxic chemicals in them and if full you can be most foolish emptying them...but *SAFELY* please!). Tell them what you want to do and they will often turn loose of them at scrap rate!

Thomas

[The Iron Dwarf]

I empty old CO2 tanks and extinguishers with my mig welder, generally about 20% of my gas is free

[The Iron Dwarf]

I empty old CO2 tanks and extinguishers with my mig welder, generally about 20% of my gas is free

[Ingelri]

We used to be able to get rivet and porthole punch outs from naval yards that made excellent dishing forms. In fact, my breastplate dish and my helmet dish are both from a naval yard. I also have one Iron Mongers dishes and a bottle bottom. All work well.

Regarding the bottle bottoms, I plan on filling the void with shotgun lead shot that you can buy in bulk at Bass Pro Shops and then welding a plate on the bottom.

[Marco-borromei]

I made my metal dishing form by welding a sheet of 3/16" steel over some 4" thick walled pipe, then i heated it up good and hot and bashed it into a dish with my shot-put-on-a-stick. afterward I poured a bunch of molten ead into the base.

It worked good and didn't really ring at all, until the hunk of lead broke free and fell out the bottom. </snip>

I did this too, but I welded on a botom plate, torched a whole through the side, and then filled with lead.

10" pipe, 3" long section
Two 12" squares of 10 gauge steel
$25 total at a local steel supply, outdoor ironwork shop.

Weld on one flat plate, inside and outside edge of pipe, heat over forge or with torch and dish to 1" deep.

Torch cut or drill a 1" hole in the side of the pipe. Start melting a LOT of lead.

Weld on the other flat, heat and dish to 1/2" deep.

Weld a scrap hoop of barstock on the side fo the pipe as a handle, you'll need it.

While still hot, weld a cone of scrap sheet metal onto the side hole to act as a funnel. Pour lead in carefully until full. Allow to cool undisturbed.

Torch or grind off the funnel. Weld a scrap of that funnel sheet flat over the hole.

The propane to finish this cost about $20. Lead was all scrap I've collected, but you can skimp on lead by using old nuts and bolts as aggregate, its just more work.

the end result is a solid, HEAVY, silent dishing form with 2 differnt profiles... if I ever bother turning it over. Did I mention HEAVY? Set this on a seriously reinforced table or anvilstand.