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Ghugly
11-04-2007, 07:28 PM
My new smelter. I made it using a propane tank and a burner made from pipe fittings. On its test run last night I was able to melt over 100 lbs of wheel weights in less than a half an hour. More than enough heat to do the job and totally stable. I made it all from scrounged junk with the exception of perhaps $10 or so of pipe fittings and a can of paint. It's kind of cool......with the pot off the top and under full power, it shoots a blue flame about 4 feet into the air :-D.

MT Gianni
11-04-2007, 10:58 PM
kewl.

hunter64
11-05-2007, 12:03 AM
I was kind of thinking of doing the same thing. What does your burner look like? I was thinking of using 3/8" pipe in kind of a U shape with a series of small holes drilled along the top of the pipe and seeing what I could come up with.

Ghugly
11-05-2007, 12:53 AM
I was kind of thinking of doing the same thing. What does your burner look like? I was thinking of using 3/8" pipe in kind of a U shape with a series of small holes drilled along the top of the pipe and seeing what I could come up with.

The easiest way is to do a search for forges, there are a lot of plans and drawings available for natural gas burners using the venturi effect. Here are two of them. Mine is sort of a modified version based on what I saw in front of me at the hardware store. The amount of heat we need is pretty small compared to what you can get using this type of burner. My first attempt was for a gas fired kiln. The burner worked well, but I wasn't quite getting what I wanted 'till I crammed my wife's hair drier into the air intake. Then it took off! Sounded like a jet engine and the fire bricks went from that red-orange glow to white hot in a hurry. Naturally aspirated will get you where you want to go. If you want to blow the bottom off the pot.......... ad a blower.:-D

hunter64
11-05-2007, 07:37 PM
Ghugly: So did you use the fittings as the burner or the fancy burner assy. that you buy in the store? I have looked at lots of sites with foundry's etc and they are not cheap or easy to make. In my line of thinking a used water heater burner, a thread coupling to taped thread, a valve and bbq hose. Everything for a few dollars except the bbq hose. The only fly in the ointment is the coupling and I am not sure they make one for a flared standard thread to a tapered thread that would work. When I do find something I will post it for those who want to use NG as the fuel.

Ghugly
11-06-2007, 03:53 PM
Ghugly: So did you use the fittings as the burner or the fancy burner assy. that you buy in the store? I have looked at lots of sites with foundry's etc and they are not cheap or easy to make. In my line of thinking a used water heater burner, a thread coupling to taped thread, a valve and bbq hose. Everything for a few dollars except the bbq hose. The only fly in the ointment is the coupling and I am not sure they make one for a flared standard thread to a tapered thread that would work. When I do find something I will post it for those who want to use NG as the fuel.

I started with a 1/2 X 1 1/4" bell reducer. I brazed a 1/4 X 4" nipple into a 1/2 X 4" nipple with enough protruding that it would extend about 1/2" beyond the end of the bell on the reducer when the 1/2" pipe is threaded into the reducer. A hole was then drilled into the center of a 1/4" cap (you may well have to play with the diameter, I am using 1/8") and the cap screwed onto the 1/4" nipple. I torched (drilling would be neater) air supply holes into a 1 1/4 X 6" nipple at the place where they would center at the gas jet when it was assembled. The 1 1/4" pipe was screwed into the reducer and an elbow and additional 1/2" nipple attached so the necessary gas supply could be attached.

I will almost certainly fine-tune the air and gas ports as time goes by, but it is close now. It is crude, cheap, quick, and easy. Its only redeeming quality is that it works.

hunter64
11-09-2007, 09:03 AM
Ghugly: I dropped by the local metal re cycler and they have a huge area out the front of the place that you can drop your unwanted metal products at 24 hours a day. There were a bunch of water heaters there and I was looking for an older style of about 30 years ago and finally behind an old furnace sat what I was looking for. They have a cast iron burner with a removable orifice in them. Pulled the burner and took it home. The 1/2" metal pipe has the orifice threaded into the end with the ridge on it to keep it on the burner air shutter, it extends about 6" and then bends 90 deg. to go up and out of the tank to the control. I just cut the pipe at the 90 deg. and brazed a 1/2" black pipe onto it and did away with having to fiddle with compression fittings etc. I wanted the cast iron style because now I can run it as hot as I want and not have to worry about the cheap burners they have in them right now. Hooked it up to the BBQ outlet and fired it up and holy cow it works great. The normal output pressure on a water tank is 3.5-4" W.C. and since I am not using a control I am getting full house line pressure at 7" W.C. so she goes pretty good. That was cheap and easy. For the heck of it I am trying what you did and made the second drawing. I didn't have time to fire it last night but I will see if I can give it a go on the weekend. Like you said it will have to be fiddled with a bit to get the correct mixture of air and the right size of orifice but man it should go when they are found. Lots of fun, and I never have to worry about running out of Propane again.

walnutred
11-09-2007, 10:56 AM
I made my propane smelter using the side burner from a propane grill. I mounted the burner to an old 14" car rim for stability. Lets see, found the grill and propane line in someones trash, found the rim in the ditch. Yes it was cost effective.:-D

Ghugly
11-10-2007, 03:53 PM
This is almost too much fun. I love the whole process. Last night my son and I smelted around 150 lbs of wheel weights and 60 lbs of solder from a radiator shop (that stuff is nasty). One of my son's buddies is interested in learning to cast boolits so we had help with the smelting and cast a couple of hundred boolits as well. We all had a great time and recruited a new guy to the hobby. There is something sort of magical and primal about flames and molten metal. And after that, you get to go shooting.

hunter64
11-10-2007, 04:24 PM
Ghugly: Sounds like you have the disease like the rest of us. It is nice to know that you can always make bullets that don't cost and arm and a leg and if the gun shop doesn't have the bullets you need well then who cares.

I was hauling a load of junk to the dump this morning and I scored an old Coleman green camp stove, the ones that use gas or camp fuel, you put it in the red torpedo shaped canister and you pump it up. Well the red thing was gone and the end of the burner was broken off but I wanted it just for the case itself. I took it home and cleaned it out, mounted my water tank burner in there and it works great. Now I have to find some more lead to melt down, LOL.

Limey
11-10-2007, 04:38 PM
....we break into this programme to bring you a news flash,

.....NASA is reporting the theft of a main thrust motor from their lastest Saturn 5.........Police are asking for anybody having any information about this incident to ring and let them know.....however rumours abound about a strange light being seen in the night sky accompanied with the pungent small of molten metal and the hysterical laughter of a group of men having a lot of fun.........based on these rumours the Police Department are casting their net further afield and are hoping to get a clean shot of these strange events themselves since the MO does not fit the usual mould of crimes in this neighbourhood, a Police spokes person said they fear it could be the work of people into heavy metal and the black arts.


Safe shooting and casting


Limey

deltaenterprizes
11-21-2007, 01:10 PM
I started with a 1/2 X 1 1/4" bell reducer. I brazed a 1/4 X 4" nipple into a 1/2 X 4" nipple with enough protruding that it would extend about 1/2" beyond the end of the bell on the reducer when the 1/2" pipe is threaded into the reducer. A hole was then drilled into the center of a 1/4" cap (you may well have to play with the diameter, I am using 1/8") and the cap screwed onto the 1/4" nipple. I torched (drilling would be neater) air supply holes into a 1 1/4 X 6" nipple at the place where they would center at the gas jet when it was assembled. The 1 1/4" pipe was screwed into the reducer and an elbow and additional 1/2" nipple attached so the necessary gas supply could be attached.

I will almost certainly fine-tune the air and gas ports as time goes by, but it is close now. It is crude, cheap, quick, and easy. Its only redeeming quality is that it works.

What size hole did you use for the orifice?

Ghugly
11-21-2007, 06:35 PM
What size hole did you use for the orifice?

I started with 1/8". This was with a 3/4" line that ran about 20' from the meter. At full throttle, I got a nice blue flame perhaps 4" or 5" in diameter and about 4' to 5' tall. With the pot on top, I was only able to reasonably use about 1/4 of the valve's capacity. It was good enough that I knew I was in the neighborhood but when throttled back the mixture was too rich and I was getting a yellow flame. When I moved the smelter to my son's house, I was working with a 1/2" line that ran a good 30' from the meter. Also, since this contraption is working without a regulator, I had no reason to assume that our static pressures would be the same and given the different sizes and lengths of feed line, I'm sure the difference in pressures at the orifice are substantial. I'm only pointing this out so you will understand that you will, undoubtedly, end up with a different orifice that works for your situation.

At any rate, the smelter now has a 1/16" orifice and seems to be just about right. At full throttle, I have a nice blue flame that surrounds the pot to about half its height. This allows me to use the whole valve and when throttled back to a nice simmer the flame is still blue, indicating that the mixture is, at least, close. The overall effect is very similar to a giant size propane torch. Of course, natural gas provides fewer btu's than propane and a similar burner using propane would provide a lot more heat

MT Gianni
11-21-2007, 09:56 PM
Hunter, I believe NFPA54 has a chart for Nat. gas orifices at 7" wc. I have one in my truck and access to it Monday if you know your btu requirements.
Ghuly 1/8" bit is equal to a #30 in a numbered drill bit. I am not sure about a 1/16th. Gianni

Dave Berryhill
11-22-2007, 02:47 PM
Natural gas orifice sizes:
http://www.joppaglass.com/burner/lowp_chrt.html

LP gas orifice sizes:
http://www.regoproducts.com/Old/LPflow.htm

Drill sizes:
http://en.wikipedia.org/wiki/Drill_bit_sizes#US_number_and_letter_gauge_drill_b it_sizes

1/16 (.0625) is between a #52 and #53 drill bit.

Ghugly
11-22-2007, 08:32 PM
I may be all wet but it's my understanding that unregulated natural gas pressures can go up to 1 to 2 psi, after the meter, of course.

hunter64
11-23-2007, 08:30 PM
Ghugly: Man if that was the case then most homes would have blown gas valves as the max pressure most will take is 1.5 psi. All homes in North America are rated for 7" water column which is just slightly under 1/2 psi. The regulator can very as much as 1"WC either way and that is it irregardless or load.

You can get by converting propane to NG with a 1/16" drill bit as long as you use a hand drill only and no power drills.

MT Gianni
11-23-2007, 10:08 PM
Some utilities allow up to 2 lbs into a house. They are generally in the midwest. All mandate a regulator in front of any appliance. This allows you to use smaller pipe at a lower cost. 1/4 lb or 7"wc is ths most common but not the only thing out there anymore. Gianni

hunter64
11-24-2007, 12:51 AM
Absolutely MT but he was stating after the meter, most farms are either 2 LBS or PFM sets and each house/structure has its own regulator for 7"wc. I have never heard of the 2 lbs inside the home and a definite no-no in Canada, the reg has to be on the outside of the dwelling. A business is ok up to 10 feet inside but that is it. Now if I could hook up my NG little project to a 2 lb set I would have some flames for sure. Better yet, if I could hook up to my service truck and cut the 3000 psi down then I could run my smelter on the company's gas. lol

Ghugly
11-26-2007, 02:27 PM
I will accept the 7" as a standard. At my home, I was running a 3/4" line very close to the meter. At my son's home, it was a 1/2" line that was running 3 or 4 times the distance and the pressure drop was enough to make a difference. 1/16" seems to be just about right for us. I'm just not comfortable in making a blanket statement that what is working for us would work for everyone. I am comfortable in saying that this type of burner can be made to work by adjusting the size of the gas orifice and air inlet. If you want serious heat with NG, skip the air inlet holes, use a "T" instead of the bell reducer, and install a blower.

Salmon-boy
12-04-2007, 01:25 AM
I've been melting aluminum for a whole bunch of years now with the Reil type burner.. They usually cost me about $5 and 2 hrs to make.

There's a REALLY good book by Mike Porter, published by Skipjack Press called "Gas burners for forges, furnaces and kilns". These burners are amazing and can be assembled in a weekend.

The only issue with using them for melting lead, it will be very easy to exceed 1000 deg F!

That, coupled with an old water heater shell, or propane tank and you'll have one hell of a WW gobbler!

mtgrs737
12-04-2007, 11:52 AM
Old water heater burners and gas valves make a cheap start for a smelter.

Salmon-boy
12-04-2007, 12:56 PM
Old water heaters are dangerous to a marriage.. Every time I go to the dump, one just happens to hop into the truck and come home with me.... :-D

They are useful for LOTS of things though!