Lining a rivet forge.

[Dave Shepard]

I broght home a little rivet forge last fall, and before I fire it up I'd like to line the firepot with something. What is best? I've been told to use either fireclay or firebricks chopped to fit in the bottom. Thanks.


Dave

[Thomas Dean]

Dave, is the pan cast iron or sheet metal. I have both and only lined the cast iron one. I have since sold it to a friend. He took the 1 day beginner class I teach and now want me to come see his barn/shop and help him find the best location to put it. The sheet metal forge I use for demos is not lined and I have not had any problem with it. But neither of them have a firepot. You would not need to line the firepot only the pan around the pot, that is if it need lining to start with.

I am just about finished with a lever type forge that has a pat. date of April 6, 1886 on it, made by the 'Star Machine Works Co. Buffalo, NY' The blower has 'C.Hammelmann's Pat. April 6, 1886 Buffalo, NY' on the side. I plan to line it this weekend as it is broke all the way across the pan. I have bolted a strip of 1/8" x 1" across the cracks to hold it together and will line it to seal the crack across the bottom. No, it is too burned up in the bottom to weld/braze it back together. Beside, someone attempted that YEARS ago with miserable results. I plan to sandblast then line the inside and paint this weekend. will post pictures before and after.

Sorry about stealing your thread. But I don't think it matters too much one way or the other about lining it. Maybe someone else will enlighten us both!

[Frosty]

Thomas:

After you sandblast it you might want to paint it with a phosphate primer to prevent rust from occurring under the liner.

A good liner for the sheet metal pans is wood ash, dampened lightly and rammed tight. A bit of white wood glue, Elmers, etc. in the water at about 1 tsp./gl will help keep it in shape.

A good hard liner for the cast pans is the old fireclay, grog, sand and portland cement refractory. As I recall the ratios are:

3pts. fire clay. 1pt grog (fire brick crushed to pass a 1/4" screen). 1pt silica sand. and about 1/4 pt. portland cement.

Soak the grog over night. Mix all the other ingredients thoroughly then add the damp grog and mix till everything is equally moistened. It should make a clump in your fist when squeezed without being sticky. It should break cleanly without crumbling.

It it's sticky it's too wet, add a little more of the dry mix. If it crumbles it's too dry, add a LITTLE more water.

Once the moisture is right let it rest in a sealed container for several hours. Then ram it into the pan with a wooden mallet or a piece of 2x4 and a hammer. Ram it good and hard. An inch is usually plenty thick and I make a little rim around the air grate like a smooth crater about 6" in dia.

When it's good and hard, use a piece of burlap and burnish it smooth and score to control shrink checking.

Burnishing makes it less likely to be damaged by iron, tools, etc.

Scoring will control the cracks that naturally form when clay dries. Ramming it up as dry as will stick helps minimize checking but scoring will cause the cracks that WILL form to follow the score marks.

Scoring is making shallow grooves in the finished surface. Expansion joints in the sidewalk, etc. do the same thing. Use a butter knife and cut about 1/8" or so deep.

Allow it to dry completely and heat cure with a small fire to start. Say a bed of split kindling a couple inches deep.

Second cure can be a layer of charcoal briquettes a couple inches deep. You want to get it good and hot so if you were to turn it over and build the fire underneath it wouldn't be overkill.

I don't know how well a green fired liner will stay in if you turn it over though.

Then again, you can go down to the river, find a bank of clay and ram it in and score. Always score wet clay or the cracks will make a mess of it.

Frosty

[BeaverDamForge]

Last thursday I made a brake drum forge to take to a hammer-in. I lined it with red mud and ash mixture, packed in with straw which controlled the cracking pretty well. I put some more mud in the small cracks but they still opened a bit when it dried.

It performed pretty well (4 hrs), there is one soft spot that needs more clay/ash and a glassy spot where the (stainless drain) grate warped and let air come up the side. I was wondering why I was having trouble controlling the fire in that area...

Good Luck!

[Johannes]

if its good quality cast iron, i'm not sure, but i think you don't really need to line it

[dablacksmith]

I prefer not to line my forges... i used to line them and found it made a mess and wasnt nessary.. clinkers stick to the fireclay and make it hard to work with ...injoy!

[Dave Shepard]

Thanks for the replies. I have seen cast iron rivet forges that have instructions to line them cast right into the bottom of the pan, so they must want you to do it. The grate is about an inch higher than the bottom of the pan, I am thinking this is to allow for the lining. It is a Champion forge.


Dave

[Glenn]

Dave, build several small fires before building the first forge fire.

[ksb]

I also have a Champion forge. As you can see the pan is cracked. And also the top of the grate is abt. 1" high. It has to clay before using in the bottem of pan. Any idea how high to clay - to top of grate ? Should it be flat across or 'dished' ? Thanks.
Ken