School Me On: Forge Burners

Here's my state of the art forced air burner made from a bathroom exhaust fan, a couple piece of 1" pipe and not to mention the Kashi cereal box. Ventura burners are nice and handy but you just don't have the control. Forced air is much cheaper to run.

IMG_1969.JPG
 
Raymond Richard said:
Here's my state of the art forced air burner made from a bathroom exhaust fan, a couple piece of 1" pipe and not to mention the Kashi cereal box. Ventura burners are nice and handy but you just don't have the control. Forced air is much cheaper to run.
Click to expand...

How hard is it to keep a reducing atmosphere with forced air?
 
add more fuel to the mix or restrict the air, piece o' cake, I can run from full oxidizing to carburizing at whatever temperature is reasonable for that type of flame, as long as I have positive pressure on the air and fuel I can mix whatever I want, my blower is an old Kirby vac with a variac on it, my gas has an adjustable regulator from Ellis, and I have valves in air and gas for fine control. I do my heat treating in an electric kiln. Forges are for forging.



-Page
 
Ray you're a hoot. Anymore low tech and you'd be running a tube from one of your cow's butts! :rolleyes::rolleyes::rolleyes:


IMG_1969.JPG
 
I posted this thread a while back that shows a dual control forge and thought it might be applicable to this thread.

Fred



Building your forge with both a manual and automatic [pid] option, has many advantages; but the key word is control.

I run my forge on manual, most of the time; adjusting the air with the manual side rheostat and the gas with the manual side needle valve.
When the temperature needed, is in the 14 to 18 hundred degree range, I find the manual side controls to be the best option.

When I am working in the 1800 and above range, I use the automatic [pid controlled] option.

When using the auto option, you are using the manual controls for your base temperature, with the auto side adding the extra gas/air mixture to bring and hold the forge to set temperature.

“Make sure to wire your system with safety in mind”.

When I activate the main electrical switch, for this system, three things take place: the pid is turned on, the blower fan turns on and electrical current is sent to the switch that will send power to the main gas solenoid, when I am ready to light the forge. When you wire your system in this manner, you can’t turn the gas on without the blower fan running.
The auto side has an inline switch that allows you to turn it off and on at will, while still allowing the pid to be used as a thermometer.

Each burner on your forge should have its own needle valve. This makes “tuning” your forge much easier. Each burner operates slightly different, depending on its location in the forge body.

Forge atmosphere is readily adjustable with this system.

Installing two rheostats on the blower fan is not a necessity, but it does give you just a little more control on the auto side. Without the second rheostat, the fan will operate at max when the pid is activated.


My main objective, when I started building this system, was: No Whoosh, when the pid turned the gas, off and on. This always made me a little nervous.
I was looking for a set up that would maintain a base temperature, which I could set manually and that would be in operation as long as the forge was lit, along with an auto controlled [pid] option that would add the extra gas/air mixture, to the system, that would bring the forge to set temperature.

I got more than I bargained for. The control options are endless.

Vulcan’s Chariot will hold set temperature from 1400 to 2400 fh. within
two degrees. You can also adjust the forge atmosphere to whatever your need may be.

It is obvious, I am not an artist. [loud laugh] If I can help to clarify the drawing, give me a yell.

Take the time to study it first. It took me a bit to figure it out when Bladesmith first got me started on it. It is in reality quite simple.

Thanks again Stacy. It has been a very enjoyable project.

Fred Rowe

<-Bethel Ridge Forge->


image0.jpg


Vulcan_s+Chariot-performance+sheet_+005.jpg


Vulcan_s+Chariot-performance+sheet_+006.jpg


Vulcan_s+Chariot-performance+sheet_+003.jpg
 
Fred.Rowe said:
I posted this thread a while back that shows a dual control forge and thought it might be applicable to this thread.

Fred



Building your forge with both a manual and automatic [pid] option, has many advantages; but the key word is control.

I run my forge on manual, most of the time; adjusting the air with the manual side rheostat and the gas with the manual side needle valve.
When the temperature needed, is in the 14 to 18 hundred degree range, I find the manual side controls to be the best option.

When I am working in the 1800 and above range, I use the automatic [pid controlled] option.

When using the auto option, you are using the manual controls for your base temperature, with the auto side adding the extra gas/air mixture to bring and hold the forge to set temperature.

“Make sure to wire your system with safety in mind”.

When I activate the main electrical switch, for this system, three things take place: the pid is turned on, the blower fan turns on and electrical current is sent to the switch that will send power to the main gas solenoid, when I am ready to light the forge. When you wire your system in this manner, you can’t turn the gas on without the blower fan running.
The auto side has an inline switch that allows you to turn it off and on at will, while still allowing the pid to be used as a thermometer.

Each burner on your forge should have its own needle valve. This makes “tuning” your forge much easier. Each burner operates slightly different, depending on its location in the forge body.

Forge atmosphere is readily adjustable with this system.

Installing two rheostats on the blower fan is not a necessity, but it does give you just a little more control on the auto side. Without the second rheostat, the fan will operate at max when the pid is activated.


My main objective, when I started building this system, was: No Whoosh, when the pid turned the gas, off and on. This always made me a little nervous.
I was looking for a set up that would maintain a base temperature, which I could set manually and that would be in operation as long as the forge was lit, along with an auto controlled [pid] option that would add the extra gas/air mixture, to the system, that would bring the forge to set temperature.

I got more than I bargained for. The control options are endless.

Vulcan’s Chariot will hold set temperature from 1400 to 2400 fh. within
two degrees. You can also adjust the forge atmosphere to whatever your need may be.

It is obvious, I am not an artist. [loud laugh] If I can help to clarify the drawing, give me a yell.

Take the time to study it first. It took me a bit to figure it out when Bladesmith first got me started on it. It is in reality quite simple.

Thanks again Stacy. It has been a very enjoyable project.

Fred Rowe

<-Bethel Ridge Forge->


image0.jpg


Vulcan_s+Chariot-performance+sheet_+005.jpg


Vulcan_s+Chariot-performance+sheet_+006.jpg


Vulcan_s+Chariot-performance+sheet_+003.jpg
Click to expand...

WOW :eek:
I'd say I've been schooled for sure. With this setup, would you eliminate the need for a HT Oven since it can maintain a certin temp?
 
drdoc said:
How hard is it to keep a reducing atmosphere with forced air?
Click to expand...

What is a "reducing atmosphere"

sunshadow said:
I can run from full oxidizing to carburizing at whatever temperature is reasonable for that type of flame, as long as I have positive pressure on the air and fuel
Click to expand...

What is "Full oxidizing" and "Carburizing" -I now I've seen these terms before in cutting torch tips but don't know what they mean.

What exactly is "positive pressure"?

I know these may seem simple to everyone else, but indulge me :confused:
 
jawilder said:
What is a "reducing atmosphere"



What is "Full oxidizing" and "Carburizing" -I now I've seen these terms before in cutting torch tips but don't know what they mean.

What exactly is "positive pressure"?

I know these may seem simple to everyone else, but indulge me :confused:
Click to expand...

Grasshopper, I'm sure the answers you seek are in the stickies somewhere, and reading should be in your future, but for the sake of brevity

Reducing: incomplete combustion producing an atmosphere rich inCarbon Monoxide which will exhibit a propensity to wrest oxygen from such compounds as Iron Oxide "reducing" them from ore or rust to (hopefully) metallic iron

Carburizing implies that combustion is so far from complete that it leaves soot behind, oxidizing on the other leaves excess O2 in play, ultimately reacting with the surface of your blade to pull carbon out (decarb) or leaving some oxygen behind stuck to the iron. I'll let you figure out what that's called:D

-Page
 
jawilder said:
What exactly is "positive pressure"?
Click to expand...

In this case, it's exactly what it sounds like. There's more than local atmospheric pressure behind both air and fuel, hence "forced air". A venturi burner uses a vacuum created by the flow of fuel and the shape of the intake to pull air into the mix.

The big difference, in terms of reducing, oxidizing, or carburizing atmosphere, is that with a venturi burner, the air-fuel mix is dependent on the shape of the venturi and the fuel pressure. With forced air, the positive pressure fuel and air feeds allow you to adjust the mix from either side.

Hopefully, that didn't make things more confusing....
 
drdoc said:
In this case, it's exactly what it sounds like. There's more than local atmospheric pressure behind both air and fuel, hence "forced air". A venturi burner uses a vacuum created by the flow of fuel and the shape of the intake to pull air into the mix.

The big difference, in terms of reducing, oxidizing, or carburizing atmosphere, is that with a venturi burner, the air-fuel mix is dependent on the shape of the venturi and the fuel pressure. With forced air, the positive pressure fuel and air feeds allow you to adjust the mix from either side.

Hopefully, that didn't make things more confusing....
Click to expand...

Thanks for catching that one Doc,;)

-Page
 
jawilder said:
WOW :eek:
I'd say I've been schooled for sure. With this setup, would you eliminate the need for a HT Oven since it can maintain a certin temp?
Click to expand...

Not really; this forge can be used in a pinch but an electric oven with ramp up and temp hold cycles is better.
This forge is made for both welding and forging. It responds quickly and holds temp within a couple of degrees.
I do use it for normalizing and annealing; but when it comes to hardening I use another system.

I used Bladesmiths plans and also picked his brain when I was building it. Stacy was very helpful through the building process.

Fred
 
I don't want to hijack this thread, but I have a question about the forced air sets I'm seeing. They all appear pretty similar and the part that riases a question is the elbow where the gas is inserted into the air stream. They all appear to be like IG's and a 90 degree elbow drilled out with a peice of 1/4" black pipe welded in. When looking at the set up, I keep thinking that using a T fitting and cap similar to a side arm burner would be easier to put together from the standpoint of ensuring proper alignment down the center of the pipe leading to the forge.

I understand that it requires a few extra plumbing bits, and the flow of air would have a bit more turbulence, but would those factors be significant enough to rule it out as an alternative for someone who isn't sure they could line up the fuel tube as accurately?
 
When it comes to lining up the tube, why not a y shaped reducing tee or just a y shaped t for that matter. Or maybe a grinnel reducing t, it has the elbow but on the elbow is another opening smaller than the other two. Use a plug, drill a hole like for the venturi burners. Same principal, yes?
 
Another question is... I noticed that IG drilled a 1/8 hole in his 1/4 gas "sprayer" whereas ABANA drilled a 1/16 hole. Does it make a difference?
 
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