October 31, 2006

Propane Tank and LP Gas Forges

My apologies to those of you who read my posting on IForgeIron.com, as the first part of this post will be very familiar to you. Scroll down to see my thought on moving from "have tank" to "have propane forge". For those who have not been to IForgeIron, they have blueprints (step-by-step instructions and photos) of a few burners and gas forges.

My dad used to drive a propane truck, going to houses and filling their tanks. I told him once that I could use a propane tank, and he mentioned a 275 gallon tank on a trailer. That seemed a bit large to me, but then he remembered a smaller tank that came off of a tractor or a truck. It is a 43 gallon (358 pound) tank, with a gauge to see how full it is, valves for liquid, vapor, bleed off, vapor return, etc. And of course, a pop-off valve just in case someone fills it too full. This tank is heavy! I could lift one end, but we used a tractor's front end loader to load it into my truck.

I still need to get the gaskets inspected, get a cap for one of the return lines, paint it, and get it filled. After that, I will stop by my brothers to see if the hose, regulator and (hopefully) gauge from his old barbecue grill will be useful. I would prefer to have a "hard line" rather than hoses for my daily use forge, but I would also like to have a portable forge.

I would like to have two propane forges at the house. One of them should be a small, portable forge for demos, Saltfork Craftsmen's meetings, and going to a friends house (informal hammer-in's). I'm thinking about a freon tank forge here. The other should be larger, and capable of heating a car or truck coil spring for straightening. I would guess that would require a 12 or 14 inch diameter shell. So far, I am thinking of buying a pipe burner kit, some dura-wool and a small tub of "Plistix 900F" and making the freon forge. After I use that for a month or two, I will have a better idea about my needs. Maybe instead of making a large forge, I will get a T-Rex burner and make a brick-pile forge.

To satisfy your propane forge browsing needs, here are some links:
Zoeller forge price list
Rex Price's (T-Rex) Hybrid Burners
Chile Forge
Ellis Custom Knifeworks
Cashen Blades gas forge combustion processes

October 24, 2006

Making tools to make hammers

A few weeks back, my blacksmith friend Tim mentioned that we should get together and make some handled tools - hammers, handled punches, fullers, etc. So last weekend, I went over to his shop, and we made a slitter and two hammer eye drifts. I brought some axles, leaf and coil springs and we picked an old 1 x 7/8 inch fixed axle to draw down for our drifts. We made them about 16 inches long, with the widest part at about 12 inches. We took turns on the 16 pound (7.25 kg) sledge hammer, and really moved the metal! We tried to keep our pieces straight as we forged, by doing some correcting blows, but there were still a few twists near the small end. Tim cleaned up one of the drifts with a flap sanding disk, and it looked beautiful. It needed a small amount of cleanup on the edges, but the overall shape was exactly what I was aiming for. We also straightened out a few coil springs using a bending fork mounted on a 4x4 inch piece of tubing set into a concrete pad with a 3 prong socket. The pair of heavy tongs that I had made came in very handy. Tim put a piece of square metal tubing over one end of the spring, and I held the other end with tongs, and we maneuvered the spring over to the bending forks. Then he would bend and I would position the spring for the next bend. After this, we ran out of time. At our next work session, we will smooth and straighten out the drifts, and hopefully make a few handled slitters or other small tools from our stash of car axle material. I think the axles and coil springs are 4140 material, but I am quite sure that they are steel!

Regarding the 16 pound sledge hammer, we didn't do the circular overhead swing, but rather a more controllable (and more tiring) swing where we lifted the head to eye level and then pushed or dropped it down. This was partly because I am not used to working with such a heavy hammer, and also because his anvil was only about 125 pound As I understand it, the recommended hammer to anvil ratio is between 1:15 and 1:25. With a 125 pound anvil, this works out to an eight pound (4 kg) hammer at most. Also, the anvil was mounted to a tree stump, and was 8 inches higher than I would like for sledge work.

I am sorry that I don't have pictures, but I will try to make up for it next time.

October 18, 2006

2006 Saltfork Conference

Another member of our group, Tim, kindly invited me to go with him to the SCABA Annual Conference in Perry, Oklahoma. We had demonstrations by Tal Harris, and the Brazil brothers - Brian and Ed. The building was excellent, with bleachers close to the demonstrators, a separating wall to isolate sound and sand on the floor so we would not have to worry about fires. To all SCABA members - there should be a tape available early next year.

Tal showed us how to design a railing with pierced joinery, tenons and banding. He used a few specialized tools that he either made or adapted for his purposes - a 6 inch traveler, a bolster block with a slit cut, a Z shaped auto-centering scoring tool, an offset punch, an angle iron measuring stick (with small clamps to preserve a measure across several cuts), a ruler that measures length on one side and the radius on the other. He commented - if you look at an older piece and it looks impossible, there was probably a forge weld involved. His design explanations only involved simple math, using the perimeter, circumference and area formulas as he converted a slit into a circle and then a square.

Brian and Ed demonstrated tool making, animal heads, an eagle wing, and several flowers. They used both a traditional "London Pattern" anvil as well as a european anvil made more like a simplified swage block - it was a piece of 2.5 or 3 inch plate, turned on edge, with flat, 2 inch rounded fuller, 1/2 inch fuller, cutting edge, hardy hole, pritchel hole and a small horn.

Things that I learned:
An offset punch allows access to the inside of a closed shape.
Measure carefully.
Marking with a diamond punch makes it easier to spot a mark after the metal has scale.
Scale will flake off when an item has been upset some.
Quenching a piece can shrink it a tiny bit (maybe 1/16 inch over 6 inches).
You can draw out faster if you slightly lift the hot piece off of the anvil between blows, thus preserving the heat.


October 03, 2006

What is in a clothes dryer?

Recently, I acquired 2 washers and 2 dryers. After dismantling my first dryer, I was somewhat surprised at how simply they are made. The frame was nothing more than the painted sheet steel box that you see from the outside. Inside was a single sheet running top to bottom acting as a drum support and motor mount.

From the first drier, we have:

  • 1/3 hp open-frame 110 volt motor, rated for 5.8 amps

  • sheet metal blower housing

  • lots of flat sheet metal.

It looks like we have parts for a coal forge: sheet for the "table" area, as well as the obvious blower. I bought a varistor at a garage sale, rated for 5 amps. I wonder if I could mount the varistor in line with the blower, and not use an air gate?

I was pleased to discover that the blower motor (which also spins the clothes drum) was 110 volts. The dryer was a 220 volt unit (two 110 volt lines, and a neutral) but I guess one "leg" ran the blower, and the other "leg" operated the heater. My primary reason for obtaining these units was to gather parts for a power hammer, although Jim C had a forge blower blueprint using a dryer fan on IForgeIron.com, so I wanted to try that out too.

Quest for Power - Gathering Supplies

After the September 2006 SCABA Meeting at Dan's house, I have been wanting a power hammer. So I have been scouring the internet, looking at pictures, plans and opinions. So now I have to decide whether to build an Appalachian Power Hammer, a Little Giant knockoff or a Kinyon style air hammer. So far, Rusty is winning the battle, with potential out-of-pocket expenses of $200 US dollars or less, but the simplicity of an air hammer has its charm too. Maybe I will build an air hammer someday when I have $1000 US dollars or so for the huge air compressor, air cylinder and fittings. Actually, there is a very informative thread on IForgeIron.com regarding hammer weight and cylinder dimensions for Kinyon style hammers. It seems like I might be able to get by with less than $1000 if I only want a 20 or 30 pound hammer. If I had alot of money, I would just get a Phoenix Air Hammer and get back to forging.

While I really want a power hammer, I also want to keep learning hammer control and basic "At The Anvil" blacksmithing. I don't want to become so dependent on power tools and dies that I can't work without them!

So far, I have the following:

  • a set of trailer overload leaf springs

  • a few broken pieces of leaf spring

  • several car and truck coil springs

  • three car axles

  • one 12 in x 48 in x 1 in thick plate

  • one 9 in x 32+ in x 2 in thick plate

  • two junk washers and two driers

  • access to some rusty old farm equipment

  • ... and determination

I intend to scrounge a 1/2 HP electric motor from one of my washers (110 volt) or dryers (220 volt). Obviously the washer is preferred, unless the dryer has a universal motor that can be run at a lower speed on 110 volts. That would be awesome, since I don't need more than 100 beats per minute. I've read that 220 volt motors are more efficient. Maybe I just need to get my shop wired for 220.

Links mentioned or reviewed while creating this article are: