maddog

Dodge, thats a beautiful piece of work. Must have taken many hours of grinding.

It might be good to include the location where the anvil was purchased since availability and price varies widely with location.

PW 97# $220 in NM USA Seriously used cond.
HB 355# #850 in KY USA Significant mfr defects and heavily swaybacked.
HB 120# #180 in NM USA major torch damage on the horn and cutting table.

At what temp does the pressure start to fall off? My set up is in an unheat garage and from all the talk, I will have problems with gas pressure unless I find a way to warm the tank.

What say you?

Problems start at about 0F. At -44F propane will no longer boil and the tank produces no gas at all under pressure. Even in a heated garage a 20lb tank will fall to this temperature because of the heat that is being drawn out of it by the evaporation of propane.Propane vapor pressure

The "recommended" solution is to use a bigger tank - 100lbs. Many people who use small tanks float them in a tub of warm water. I have been using a small electric heater to keep the tank from freezing. Others have questioned the safety of this method.

See my recent thread in Gas Forges on Freezing Propane tanks for a more detailed discussion of this topic Freezing Tanks

eric: I will post results once I know whether it holds together. This is to be a very small forge with a 4"x6" chamber for economy and quick heat up. I want a forge that I can run for just an hour or so without having to invest a lot of propane in bringing it up to temp.

Dodge: My thinking is much like yours. The refractory has little insulation value. It's purpose is to provide a durable liner. The wool is there to hold in the heat. I've not been satisfied using kaowool with just a thin skim of some coating. I always have cracks develop and then the combustion gas gets into the wool. I run my forges hot and when the wool is exposed to combustion gases at that temp, it dies quickly. Plus it's very vulnerable to being damaged as the work goes in and out.

My concern is whether mizzou will work when used in a such a thin section and without being rammed. I will just have to try. If it doesnt hold up I will make a form and cast a tube about 5/8" thick.

Mizzou, Greenpatch & Satanite are all about 60% alumina and 40% silicon dioxide. Pretty much any refractory that is specced up to 3000F is going to be 60% Al oxide or higher. I believe resistance to flux depends the binder that is used. Refractories with a high phosphate binding do better when exposed to flux.

I am going to try using an SS drip pan on the floor to catch liquid flux when welding. We'll see how that works. Often I am able to weld outside the forge by making a small chamber just at the mouth.

The HF rods to resurface that plate will be very expensive. There's nothing wrong with forging on mild steel except that it dents easy and mushrooms with use. But hey, it's easy to do some maintenance with the welder and grinder every now and then. I completely believe you that it was your brother dinged the anvil But imagine it had been a hard face and chips broke off?

Grader blade is very tough stuff. Designed to be impact and abrasion resistant. If you can find a thick enough piece it would make a useful anvil stood up on edge. The one thing I dont like about your anvil is that there is no backup for the top plate which is just sitting on that webbing (I guess its a piece of plate welded in). If you can find something compact and blocky whether MS or tool steel, it will work much better than what you have now.

I'm building a small forge I was thinking of lining the kaowool chamber with 1/2" of mizzou. I find Satanite too crumbly. My plan is to lay the wool out flat and butter it with mizzou about 1/2" thick then roll it up around a cardboard tube. I will moisten the wool and keep the whole thing moist until it sets. Any thoughts?

It would seem you are using a ball pein hammer, just a larger ball than what you perceive as a normal ball pein hammer
so you can see how useful they are.

Yes this is true. But it always seemed to me that pein was too tight on a BP. I shall dress and handle a few heads and look for opportunities to use them in ways people have suggested.

Thank you very much for all the comments. It has been an eye opener. I still can't see myself using a BP as my primary forging hammer but I would like to start using them for some of the work mentioned above.

I have a bunch of old BP heads. I am thinking of dressing a few and making them serviceable. What do people recommend as a useful set in terms of weight and pein radius.

One thought: It seems to me the fact that the BP is weighted on the face side would make it more accurate when using the pein since the center of gravity will be following the handle not leading it.

.... Sorry I get cranky when it's late and cold 15F now.

You must have had a lot of cold days recently. Perhaps spring will bring a pleasant change.

The store owner is looking for a welding head that will fit the torch (all I have is a cutting head). I'll leak test everything as I connect it. Now I'm looking for a welding class nearby.

Thank you all, Roger

For welding tips, check on ebay.

Ditto to John . . .

99% of my work is done with BP's, even the heavy forging - I've always found them very comfortable to use.

How often do you use the pein when forging hot?

Added later:

I use a square faced, Hofi style hammer with a rounding face in place of the usual cross pein. I use both faces about equally. With hammers that have cross peins, it seems to me that they dont get used that often. I can't imagine using the pein of a ball pein while forging hot except very occaisonaly. To me it seems like a strange choice as one's primary forging hammer. This probably means that I dont understand how a BP can be used.

The pipe is the shell, the sheet matal tube will be the ends. The sheet metal tube has been cut in to two seperate rings and I am going to weld plate on the rings to form removable caps for the shell. The caps will be filled with either refractory cement or ceramic blanket. I will leave an opening in both front and rear cap to work through.

I have been working on the plans for making a sliding fire brick door for both the front and rear openings. But they are still in the very early stages.

I May be over engineering this thing but I think it will work. I will post a few more pictures later.

I see. You are preparing two rings that will be rims for the doors. Neat. You don't often see a rear door on a gas forge. Nice to have I guess but a plate with a hole in the center might be all you really need there.

Yeah it's over engineered. So what's new? If it's worth doing, it's worth overdoing - thats my motto :)

I know they have their use in general metal working for peening but what place do they have in a blacksmith shop? Why are they so popular in general purpose non-blacksmithing work? I pick them up at garage sales and the pein shows little or no use. I rarely use them. Mostly I convert them into small top tools. I find them unbalanced and the radius of the pein too small for most work.

I've never tried to make Damascus but I can tell you it's going to be tough to get that back on your motorcycle! I hope you have a spare.

Looks like the 3/4" was a better choice. Is that a homemade burner? If so, I'm interested to know how you made the cage?

... Blown burners are the simple, tried and true route to very high temps. Preheated combustion air would add a real performance kick, but that takes a bit more engineering.

I agree. Especially for a first project. They are far less critical in their design and provided you have an adequate blower, they can put out more BTU than a typical venturi of the same size.


Venturi burners sometimes struggle to reach welding heat. They have to be designed well and the forge design has to be appropriate with very little obstruction. The best homemade venturis are probably the sidearm (google that word for Zoeller's site) and the frosTy burner made from a pipe T. There are a couple of threads on this site where Frosty gives details about making his burner. Michael Porter's design is home made and probably higher performance than the other two, but "home made" in this case means a lot of work while the sidearm and the frosTy can be made in a couple of hours depending. There are other designs out there and some may be superior but they havent been as well tested.

Pipe looks like it will be a great shell. I don't understand what the sheet metal tube is for. Is that to be your shell or the pipe?

It is also a hazard to transport propane cylinders in an enclosed compartment. The place where I fill my tanks will not allow you to buy 100#s of propane or more, if you show up in a PU truck with a camper shell. I don't know if this is a NM State law or Federal.

I like to use an 035 mig tip on my forced air burners just so that I can get a pressure reading on a 0-30 psi gauge.

Looking at the plans Dodge posted, thats a very large burner tube for a forge that size. A wide burner means the gas/air mix is moving comparatively slower and limits the amount you can turn down the flame even with the grill as a flame holder. I would go for a 1" or similar or I would flatten the end of the tube like Jymm Hoffman does.

I just bought a leg vice, and it needs a new spring. I want to buy one from Poor Boy Blacksmith Tools on Ebay but there are three different sizes and I don't know how to tell which one I need. Can someone tell me how to find out? Also this vice has a washer that looks like it was welded but the welds broke, and another washer-like piece between the handle and clamp part that has broken welds. Do these even need to be re-welded or is it o.k. for them to be free moving. I'm sorry about the hard to understand descriptions, but I don't know what all the parts are called. I might try getting pictures up soon. Keep in mind I don't currently have a forge so I can't make my own spring or other parts. Any help is greatly appreciated. By-the-way, this is my first post.

Why don't you contact Ken Scharabo, the owner of Poor Boy Tools and ask him? He makes them. He's bound to know how to match them to a vise. He's a very decent guy.

That is NOT beginner's luck! That's nice forging.

Standard stock for tongs is 3/4" round or square. Square for large tongs since it had more material. It is some work to draw the reins out of 3/4" so the reins are often smaller stock forge/arc/gas welded onto the jaws.

I use the clay method too for shapes that are difficult to estimate. I make the piece out of clay and then either form it into the shape of the stock I plan to use and measure the length or sometimes, drop it in a measuring jug half full of water and note the change in volume.

But this trick works because in forging you dont usually remove much material, you push it around. For a stock removal project I'm not sure how to use clay for this.

Is it possible to just insulate the tank to keep it from freezing?

The basic problem is inside the tank where the propane is vaporizing and drawing heat from the liquid propane. On a warm day, wrapping the tank in insulation would prevent the air from warming the tank and replacing some of the lost heat. On a very cold day (very cold!) insulation might prevent the air from chilling the tank.

Tank storage: Propane is heavier than air and if it leaks it pools. If the tank is indoors the leaking propane can accumulate and flash suddenly. I have heard of cases where the propane has pooled in basement and blown up the whole house.

There's no free lunch. To get the hammer to hit with a given velocity requires a the same energy regardless of the arm motion.

I can swing the hammer a darn sight faster than I do when I am actually forging. But I cant control it. The main power comes from the big muscles on the torso, shoulder upper back, abdomen and perhaps even the legs. Most people have power to spare. And usually its not the big muscles that get too tired to work.

Accuracy is just as important as the strength of the blow. The more effective your hits are the fewer you will do. The small advantage of one hammer over another in delivering energy is nothing compared to wasting a whole blow. Check out Brian Brazeal's one heat tong blank video. He doesnt hit that hard and he doesnt hit that fast either. He even takes breaks to think. But every blow counts.

IMO the real question is which hammer and which motion allow you to deliver the most power with control.

Since this thread has raised concerns about safety and the possibility that someone might actually follow my example and hurt himself let me make a couple of things very clear:

My intention in starting this thread was only to share what I had done with my propane setup. I do not mean to say or imply in anyway that I am assuring people it's safe for them to do. I consider it safe enough for me to do. If you choose to follow my example, you must make your own decisions about safety and consult qualified sources for information. It is your responsibility to understand the risks involved and your decision to accept them.

I am not qualified to tell people how to use propane safely. I have no formal training and my informal knowledge is haphazard.

Anything I say on the subject of propane safety is for purposes of discussion only.

RR track is generaly fairly high carbon. I've had no luck welding it except with SS rod. It should work with low hydrogen 7018 rod, pre heat & post heat (dunno the MIG wire equivalent) but mine didn't. It cracked apart after a few days. That was back in the days when my welding was really rough so I may not have done it right. Perhaps an easier alternative is to grind some slots or notches in the flange and bolt it down.

I found this on freezing tanks. Rather long and scientific.
BUT...http://www.wardburner.com/tankfreeze.html

Interesting article and thankyou but it seems confused. The pressure in a tank of propane depends soley on the temperature of the liquid propane within it. It matters not whether the tank is 1 gal or 5000 gal. The basic problem is NOT BTU delivery but pressure! When temperature of the liquid propane falls, its vapor pressure drops and at some point, it becomes insufficient to drive enough propane gas through the forge orifice to keep it running. A 5000gal tank cold enough to frost up on the outside will not keep a forge going any better than a barbecue sized tank. It probably can deliver far more BTU than the forge requires but not at the necessary pressure. Propane Info

As far as fuel delivery rates are concerned bigger tanks differ from small ones only in that there is a larger volume of propane which has to be chilled before the pressure falls too far and they have a larger surface area through which to replenish the lost heat. A 100gal tank sitting in a subzero shop will eventually fail to deliver propane at the required pressure. The only question is whether that happens before the day ends. A 100gal tank with only 5 gals left will probably perform about the same as a 5gal barbecue tank.

As for the possibility of a BLEVE, modern tanks have an over pressure release valve set for about 375 psi. If the tank gets too hot, this valve will start opening and closing to relieve the excess pressure. This will release unburnt propane into the air which is also not a good thing but it's nothing like a BLEVE.

A propane tank in a blacksmithing shop is surrounded by ignition sources: the forge itself, the hot work piece, flying scale etc. The extra risk posed by glowing hair dryer coils seems insignificant. Nor is it necessary for the coils to run red hot in order to maintain the heat balance in the tank.

The recommended max temp for free standing propane tanks is about 110F at which point the pressure is about 200psi. This is a very conservative limit. 200psi is only half the pressure needed to crack the relief valve and you can be sure that that pressure, 375psi, is set way below the point where the tank is in danger of bursting. I am sure my tanks sitting outside on a hot summer day routinely exceed 110F. But, to be cautious, the tank, when touched should be no hotter than body temperature. This means that if you put it in a bath of hot water, the water should not be scalding hot if you want to stay within this guideline.

I doubt this applies to anyone here, but if you were seriously considering lighting a wood fire under your propane tank to keep it warm, there is probably no advice or warning that is going to save you from yourself except perhaps that you should make sure your will is up to date. It will be needed sometime soon.