Gas Burners

I don't know for sure if my gas barbeque has a regulator, but I would lean toward using backyard cooking technology where you can. If it is safe for a guy with six beers in him then it should be safe for you.

I have not built my furnace yet, but I skipped the charcoal and gas fuels. Dave Gingery has an electric furnace book. I won't have to worry about gas leaks or running out of fuel in the middle of a melt.

Good luck. We would love to have you take pictures and let us know how it is going.

Bruce

Where I live, you find everything in the bush. When I need a burner, I drive around and get one out of a thrown away barbeque set. You can make a burner quite easy.

In principle it nothing more than a flat square box of about 1/2 inch thick. The sizes you can adapt to your BB'que. In the box are a lot of very small needle size holes.

You will need a gas volume knob with a regulator valve if you work with propane. If you have difficulties finding one, I still know places with free spares.

This is not my strong suit, but: it's all about heat and temperature. Propane burns at a certain temperature with air, too low to melt some metals without a good blower. Add oxygen and you have a serious burner.

I'm not sure if charcoal briquettes burn like coal. A forced air coal forge can get plenty hot.

If it were me, considering the cost of propane, I would use coal. Have the burner so you can add coal during the burn, and shake the grate to drop ash. A good blower, hand or power, will get it hot.

You may even end up with a two stage setup, where you preheat with a cheap fuel, and only use the expensive fuel to get the final high temps.

Hello Normbourne, I have several GOOD links on burners and foundry/forges.

The list starts here Zoeller forge, LP-Gas regulars, simple homemade burner, Reil Burners, Mongo burners, weekend casting.

There a lot of good info in these links on building different sizes of burners. Some examples of other peoples work. Some safety related stuff about propane and finding the hardware to go from tank to burner.

In building and using burners different sizes it comes down to propane gas flow. A lot of the newer bar-b-q gas regulars and the ACME connectors to the tanks up to 40 Lb's. The connectors are flow rated in BTU's. The safety connectors colors Black 70,000 BTU/Hr Good for grill usages, Green 200,000BTU/Hr, Excess Flow POL or Red ACME connectors are NOT for grill usage or low pressures.

The color hand wheels are design to fail if there a fire or high heat around the tank. They allow the connector to be pushed off as the auto close valve spring in the tank connector pushes/close the opening.

"but I,m in the dark as to whether I need a regulator on the gas line, or not."

DO NOT CONNECT DIRECTLY TO A PROPANE TANK TO BURNER UNLESS IT'S DESIGNED AS SUCH.

I do have a "weed torch" with a built in regulator for a 20Lb tank. It has about 10 ft hose that goes to the handle/control valve.

The limiting factor for propane tank size is the liquid to vapor conversion and total BTU capacity. Some of the burners designs you can find through the above links require either tanks connected in series or larger size to operate correct.

There are several good sites on home foundry to find info on how other people set theirs up.

Never less you know working with high temperatures and molten metal is hazardous. Also building from plans or designing your own burner can have its own hazards in building, testing, and adjusting. Best to mount a burner solid when running/tuning. And do I need to say it DO IT ALL OUTSIDE SAFELY AWAY FROM ANY THING THAT CAN BURN. Also the heat zone in front and around of the burner running can be several feet or further depending on size. So point it in a safe direction and at a height safely above the ground and keep people and pets back.

A burner running good in open air will need to be readjusted when it's installed in either foundry or forge.

Let us know how your trials and tribulations go an/or start a blog on your foundry what works or not.

Charles

What are you melting?

I went through this process some time ago, using chracoal to melt aluminium, and since I was lucky enough to have a small electric furnace for ceramics, I bunged the crucible in there and the metal came out much cleaner and it was a lot easier.

Electric is good if you don't need a high carbon atmosphere and the chance of carbon monoxide poisoning is a lot lower. You could get this with poor combstion with charcoal or gas. Be careful.

Colin Croucher [col_jan@bigpond.com]

The above email address is for the bloke that writes the "Hot Metal Ezine" he also can supply you with a complete and foolproof recipe for a gas furnace.

As you will see from Col's writings, yes you do need a regulator and a good one, not the cheapo barbeque type. The type needed is the same as is used for Oxy Propane welding and cutting.

I agree with #2 . I am in the process of building the same furnace only using electric instead of gas or charcoal. I built the gas furnace some years ago but never fired it up (got to busy). since I got interested again I have decided to build one run on electricity. The plus side for electric versus gas is enormus. to name a few-noise level, able to adjust temperature more easily-cheaper to operate. I figure You can build one for less then $200.00 depending upon Your skill level. It will reach temps of 2300 degrees F. There are a few places on the internet that can supply You with all the parts needed. One that comes to mind is www.dansworkshop.com

They have downloadable plans for a small fee, I think $3.00.

If you don't want to build Your own You can always check on line for electric kilns at ebay and other online stores.

to answer Your question about a regulator, If using propane yes if using natural gas You actually need a blower to increase the pressure which I believe is only about 3 psi

oilcan13

Thanks guys, the info submitted, is great stuff, it's certainly got me thinking. The comments on electric furnaces, is certainly thought provoking, and set me on a train of thought. It,s made me think along the lines of an induction furnace, whereby an alternating magnetic field would act directly on the metallic contents of the crucible. Perhaps the power source could be one of these cheap hobby welders, which would then afford some sort of control. Does anyone have any thoughts on that ...?

OK Guys, I converted to gas fired furnace, but am having trouble getting enough heat. At first I used a barbecue regulator, rated at 2.7 KPA, but this appears to be woefully inadequate. I then tried directly off the bottle, but got a bit anxious when it started to roar...!! My question is what is the danger of operating directly off the Bottle..? Is there a possibility of a flameback to the bottle, and subsequent explosion ..???? The burner is homemade but it appears to work fine, I've used a design based on the "Reil" type burner, so there is no problem there. Any ideas guys. ..??

Read my previous post. A quality regulator is essential. The type used for Oxy Propane cutting is the item companies such as BOC, Harris and Air Liquide make them and they are available through anywelding supply. They are not a hardware store item.