Hot enough?

Damn! I now have seen it all :eek::D

Stacy just said all that needs saying but below is the best part.

If you haven't changed the venturi burners beyond reversal, it might be best to convert back to the way the forge was designed to be run.

You can make a damascus forge ( vertical works best)
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I think the only question above that I did not answer in the post just above it is the one about the choke plates on the original venturi, this model NC forge did not have choke plates. The propane manifold tube was the venturi choke, it somewhat obstructed the intake of the mixer tube. I moved the propane manifold back out of the mouth of the intake and into my blower tubes a little for more flow. I may need to move it a little more. As I mentioned above, I bored out the mixer tubes for more flow, I also opened up and smoothed out the throats of the mixer tubes with a die grinder. Any more thoughts? Thanks Mark
 
Don Hanson III said:
Damn! I now have seen it all :eek::D

Stacy just said all that needs saying but below is the best part.
Click to expand...

I am not sure what "beyond reversal" means, please explane. Tomorrow I am going to open up some orifices, On the forge, I mean. Yeah I know ya wan't one like it Don. By the way, what significance does the sunfish have? Fishin' sunfish is the one thing I really missed after I moved up here, the really big ones. Thanks Mark
 
What I meant by " Beyond reversal" was that if you can remove the blower manifold, and still put it back the way it was before the conversion, that may be the best idea.

An example of the situation you are in would be a Ford Escort ( used merely for an example).
It comes with a 4 cylinder engine that is designed to safely move the mass of the car at highway speeds.The engineers put a lot of work into it to match everything. All the car's steering and brakes, etc. are designed to run at that level. Sure, it would be nice to have faster acceleration , a higher top end, and be able to haul two or three anvils around in the trunk. But putting an eight cylinder, turbo charged monster in the car won't really accomplish much, because the car wasn't designed to go faster, survive higher G-forces, or handle more weight. The car will fall apart or just not handle well with over-sized engine and larger loads. If you really need a work vehicle, get an F-250.

For damascus work, many smiths make a dedicated blown forge. It is often a vertical piece of 12" pipe, usually about 12X18". The inside is lined with 2" insulating wool, which is coated with 1/4-1/2" of satanite, and that is coated with a good layer of ITC-100. The bottom floor is often filled with 2-3" of kitty litter to catch the flux drips. The top is insulated the same as the sides, and is removable for re-lining repairs and kitty litter changes. The ports are arranged on opposite sides, about 6" down from the top. The burner enters at a tangent about 6" up from the bottom. This is a simple build, and since it is used to achieve welding temps, is designed to run wide open.Thermocouples are not needed, and don't survive long at welding temps. The gas and air mix
valves are used to adjust the chamber atmosphere to keep de-carb and scale down. You can get anything you need in forge building from Darren Ellis:
http://forgegallery.elliscustomknifeworks.com/

I don't know what your forge experience level is, but you do know that the forges like yours will need to run for 5-10 minutes to fully heat up to welding temps? This is a function of the refractory chamber needing to slowly come up to full heat. A properly running forge has the chamber sides at the desired temperature.

If you drill out the gas jets, the forge will work better as a blown forge. There is no orifice or jet in a blown burner, just a place where the gas comes in and mixes with the air flow. In a venturi burner, the low pressure created by the high speed gas jet from the orifice draws the air in ( venturi effect). Some venturi burners have a sliding or rotating metal plate that can be moved to adjust the amount of air drawn in. On other venturi burners, the orifice position or size is adjusted to get the proper draw. On a blown burner, you want at least a 1/8" hole or tube to bring in the gas. There should be no jet.....and the position will make no difference, as long as it is at least 6" or so back from the burner flare ( which you don't have either).

Here is a good explanation by Kevin Cashen on the operation and designing of blown burners and forges. Make note of his advise on the air and gas controls.
http://www.cashenblades.com/info/gas_forges.html

Stacy
 
I have so far built 5 propane powered blown forges, all hit welding temps easily. I typically run a 1/16-3/32 propane orifice (much bigger than the NC orifices on my NC forge)
your frankenforge is interesting, but I suspect if you are using the original NC jets, you are not getting enough gas, and if that blower is not meant for use against pressure, you are not getting enough air. A squirrel cage blower is generally volume rated for free air flow, forge blowers are generally working against static pressure, for instance I got a 160 CFM squirrel cage for my first build, the restriction of the burner , and the pressure of the expanding burning gas in the forge cut the airflow dramatically, probably down to 30-40 CFM, (It was a blower sold by Centaur forge as a forge blower, but was not actually designed for use as a forge blower)
With 4 venturi burners you were probably making more heat than your current setup, unfortunately by boring out the venturis you may have ruined them.

-Page
 
Mark Knapp said:
I am not sure what "beyond reversal" means, please explane. Tomorrow I am going to open up some orifices, On the forge, I mean. Yeah I know ya wan't one like it Don. By the way, what significance does the sunfish have? Fishin' sunfish is the one thing I really missed after I moved up here, the really big ones. Thanks Mark
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Mark, Stacy answered the "beyond reversal" but I'll add a bit. The NC is a well engineered forge and would be best if returned to the way it was. I've been making damascus for close to 20 years and have bought and built 6 or 8 forges. I like my NC for general forging but not welding. Go to Don Fogg's web site and look at his vertical forge. I built one like this 10 years ago from a 16" pipe and will never use anything else for pattern welded steel. I can build one of these in half a day and get everything for the burner at my local hardware store.

The 'Sunfish'? I love to catch and eat Bluegill, Brim. I also used to make folders based on the old Sunfish or Elephant toe pattern.

Lot of good help here at BF but I don't think you'll ever get "Franken Forge" to work as a very efficient welding forge.
 
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Many thanks to all, I really appreciate it. I have considered many of these points before starting the attempt. I have really tried not to dog D.E., I am sure they are fine people but I tried to order a forge about two months ago and then parts to build my own. They just have not answered my emails (after the first one), they are pretty busy, sorry for that. I do have another venturi forge and don't think I need two. So it seemed the most direct route would be to convert. I am probably way too commited to the conversion now to scrap it all. I hope I don't have an Escort. Today I will bore out the holes and let you know how it goes.

You guys have all been very helpfull. Where do You fish for the sunnies Don? from the "Bream" I'd say south, Made any fillet knives? show us a picture of one doing the job on a bream, if you got one.

I got a pretty good knife for Christmas too, even though I was late for KITH. Mine was one of Bob Hook's JS knives, I will post a picture when I can. Dave, Bob says hi back.

Again thanks alot everyone Mark
 
OK, I drilled the nozzles out to 1/8 inch, the forge is a whole nother animal whithout jets in it. You can't light them with the spark lighter the NC came with can you? I singed some stuff. I will need to do some evening out later on. Now it seems that the regulator only needs to be open a crack. With my blower WAO I cant get the dragons breath very small, about 10 inches is as small as I can get it. I need more blow, agreed? To answer a couple of other questions, I been making damascus for about six years with the NC and accepting the inconsistant results, it has made some good knives though. You can see some of them here, www.markknappcustomknives.com if you like. I understand "reversal" clearly now, I thought you might have been talking about reversing jets or chokes or something in the tubes, I guess I am capable of some things, just not backing up. We are intellegent, we can make this work. Don't give up on me. I'm going to get anather fan. Thanks a lot Mark
 
Mark Knapp said:
Where do You fish for the sunnies Don? from the "Bream" I'd say south, Made any fillet knives? show us a picture of one doing the job on a bream, if you got one.
Click to expand...

Mark, I grew up in the deep south, been fishin for bream (ha, I spelled it wrong before) all my life. Now I fish in the Ozarks but my favorite Bluegill lake is Real Foot in western Tenn.

Hope ya get that beast workin right. One prob might be, too small a chamber for all that you're pumping into it.
 
Mark,
A better/bigger blower
A gate valve in the air manifold
A needle valve in the gas line
Use a long flex-neck fireplace lighter to light the forge with

Try those changes next, and I bet it runs a lot better.
Stacy
 
bladsmth said:
Mark,
A better/bigger blower
A gate valve in the air manifold
A needle valve in the gas line
Use a long flex-neck fireplace lighter to light the forge with

Try those changes next, and I bet it runs a lot better.
Stacy
Click to expand...

Great, I will do it, I think I am pretty close. Thanks Mark
 
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