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I Forge Iron

Duck's homemade propane forge


sfDuck

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To start with I took an old 20 lb. lp tank and cut the handle top off with an angle grinder with a zip cut. Then I cut the Brass valve of off the top. (no sparks Yet) Then I filled it with water,a little difficult with the small opening. So I used a hand pump fire extingisher and a reed to see the water level. When full I used my grinder again to zip the top and bottom off, leaving 2 inches from the outside edge. Then hammered the edge in to the centre for a door flange. I'm planning on a single burner, top mounted to a welded flange so I can adjust the depth of the spud into the forge. The doors (both ends) will be a square frame with chains welded to the top edge. That way I can push stock through both openings and just heat the middle. I want to put a window in the side to see how long it takes for me to burn up my projects? Any suggestions for a window material? Mica, lexan,tempered glass, what? Thats it so far, stay tuned for next weeks cliff hanger! ...Duck

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Nothing listed will remain transparent at temperature. Once it starts to glow it will be opaque. Just insulate it well and look in the door like everybody else.

I do understand going through the brass valve, but your electrical machine sparks on the inside. You are crazier than you thought! I am glad all went OK.

I would get a piece of belting, park a car on it, wrap it around the tank correctly, then take a non-steel wrench to the valve and take it off, or take it to a place that inspects tanks and ask for it back in pieces.

Phil

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Cutting the handles and top brass valve off a sealed bottle sounds terribly dangerous, I would never recommend this to anyone. Tanks should be secured to a fixed object and the top valve unscrewed vary carefully. I would also recommend leaving the valve open for a day or two before any of this is attempted to make sure there is no LP left in the tank. Lastly some bottles have a quick shut off if you open the valve to fast, this will fool some people into thinking the bottle is empty when in fact the valve has just closed off.

I hope no one would attempt to open or modify any type of propane bottle before they do some serious research on how there built and a safe way to open them

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All new propane bottles have a spring mechanism in them so you HAVE to have a fitting installed on them or no gas comes out. Also there is a flow valve and an OPD, which is a float valve, and sensitive to gravity. They work hard at making these things safe.

I test the valve on my exchange bottles when I get them, they sit there doing nothing. I have had the hand wheel break off on 2 bottles! (ok, it was one, the salesperson broke the other when I said it wouldn't turn)

Phil

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Naw- Duck,

The boys are just winding you up--- Just set up a camcorder about 15M away, and then proceed as before please ask one of your mates to post the video after the bang---- To show others what not to do!.


Jeepers, Duck, using any powertool on an empty fuel tank(any sort) is just plain dumb, they should be opened,vented and then preferably waterfilled prior to drilling,grinding,cutting,welding etc.

I'm glad that you had no mishaps and you may be surprised as to just how many people are hurt,maimed etc. by exploding "empty" fuel tanks.

Anyhow now that you're past the danger point you have a great start on your forge :D

Ian

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Easy now fellas, the lp tank was upside down with the valve open for about 4 Months! For propane to ignite it must be in a contained space and displace the air to a ratio 80 % propane to air for the spark to ignite the propane. That is when you shut the valve OFF! Then cut the collar or handle off. Open the valve again and cut the valve body accross the threads. The valve is solid brass. NO sparks! No ignition. No springs just a liquid relief. This leaves a hole about a half an inch into the tank. This is where I inject the water with the pump. You have to move the bottle or tank to remove any air bubble. When water sprays out the top its full. But I diped the tank with a reed used like a ramrod to check the depth and measure the level of water. This is when its safe to cut the top off the tank. The zip cut is cooled by all the water spilling out once around the tank and .........BOb's your Uncle ! The odorent used in propane leaches its way into the steel so there will be a bad smell for awhile. Then I flipped it over and removed the bottom, leaving a big metal pipe with an inside tab or flange.I have held an unlimited gas fitters ticket for more than 30 years. I guess I'd better not tell ya how to fix a 4 in. nat. gas pipe that was ruptured in a fairly clean cut. I always wondered why you had to have a hardwood taper with a 6 to 3/8 taper. I've been told metal hammers don't spark if hitting wood but you never know?

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