Propane Forge Build-Prep and Build

[John Martin]

I have a few questions.

 

I can easily get a forge body and legs for this.

 

I want to be able to weld in this.

I also want it to be as efficient as possible, IE use as little propane as possible.

 

I really want to go with natural burners or Venturi burners from elliscustomknifeworks.

 

The inside diameter only needs to be 4" wide, 3" tall, and like 12-20 inches long.

 

Also, what insulation should I buy from elliscustomknifeworks???

 

Or would it be easier, and cheaper for me to buy a two burner bladesmith forge from http://www.diamondbackironworks.com ????

 

Once i get these questions answered, I will either buy the two burner, or build my own.

Edited October 31, 2008 by John Martin

[Doug Lester]

I would use the 1" ceramic wool insulation that Ellis carries, two layers. Keep the inside to around 12" in length with a pass through port on the back side. Hard fire brick can be used for the doors on the front. Keep the inside round and have the burner hole at about 10 o'clock so that the flame hits the curve of the wall on the far side and swirles. That will help eleminate hot spots. You should only need to have one burner for that size forge and it should allow you to heat treat blades up to around 10-12"(remember, you don't need to heat treat the tangs; it's better to leave them soft). Don't have the flame coming right down onto the floor of your forge like those commercial units you're looking at do. It's impossible to avoid hot sports that way. You will also need to coat the ceramic wool with something to keep it from becoming airborne after being exposed to heat. That stuff doesn't do your lungs any good. What worked for me was about a 1/2" coating of Mizzou, though one of the other castable refractories would probably work just as well. I am totally underwelmed with using Satanite to coat the ceramic wool. The castable refractory is much more durable and it will hold the heat better.

 

Doug Lester

[Matt Bower]

Be careful about making the interior too narrow. It may sound good in theory -- less space to heat means less fuel cost -- but it can cause back pressure, and naturally aspirated burners really don't like back pressure very much. Also, I always make the interior more or less round. I think it helps distribute the heat better and, again, reduce back pressure.

 

The more insulation you can pack in, the better. Better insulation means better efficiency. I second Doug's recommendation of at least two layers. A castable hotface is a good idea, but don't get too carried away with it. It's a heat sink, and if your forging sessions tend to be short you'll end up wasting a lot of propane (and $) just heating up the castable. (It's less of a concern if you tend to forge all day.)

[John Martin]

I sent and got this back from DBIW,

 

John,

Yes, these reach welding heat easily, yellow heats are in the 10-12 PSI range, welding heat around 15 PSI. I have a customer in Oregon who welds cable Damascus at 5 or 6 PSI. They are assembled, you just need to bolt the burner assembly on top (2 bolts) and put the hose and gauge on the regulator, illustrated instructions are included. It is a 5 minute set up. I need a zip code for an exact shipping quote, but for an example, shipping to Oshkosh, WI is $29.06.

--

Dennis Meyers

Diamondback Ironworks

704-948-7676 or 980-253-9244 (cell)

www.diamondbackironworks.com

 

 

 

-------------- Original message from John Martin <john_d_martin@hotmail.com>: --------------

 

Dear DBIW,

 

I am a hobbyist bladesmith, who would like to convert to a atmospheric propane forge due to it's easy welding capabilites, and its quick even heats. As well as the easiness of starting and shutting down.

 

I would like to buy this one:

http://www.diamondbackironworks.com/catalo...775/4753617.htm

 

First, does it really reach welding capabilites easily???

How long with this forge last before I have to re-line it or buy a new one.

 

What pressure does this usually run at when welding and when running at a yellow heat???

 

I don't want to spend a fortune on propane. I want this forge to be really efficient, and if it is, I'm willing to drop the money for it. Does this forge come pre-assembled when shipped or do I have to assemble it, also what I the shipping cost, I live in Wisconsin.

 

Best regards,

John

 

I've been talking to a lot of people, and this one just doesn't seem to cut it.

 

However, I been told numerous times to go with either one of these two forges:

 

http://www.chileforge.com/forges_tabasco_details.html

 

or

 

http://www.shop.nctoolco.com/product.sc?ca...;productId=1162

Edited November 1, 2008 by John Martin

[dbiron]

I've been talking to a lot of people, and this one just doesn't seem to cut it.

 

However, I been told numerous times to go with either one of these two forges:

 

http://www.chileforge.com/forges_tabasco_details.html

 

or

 

http://www.shop.nctoolco.com/product.sc?ca...;productId=1162

 

Out of curiosity, just exactly why doesn't this forge "cut it"?

The 2 Burner Knifemaker will reach heats as high as the Tabasco, and higher than the NC Tool Forges.

It is easier to reline than either model.

It has a lower cost than either model.

What exactly is the problem with it, and why?

 

Every forge in our lineup is verified to reach 2500 degrees F, and they get even hotter than that, but the Thermocouple availability does not allow us to record temps above 2500.

They all use 2 stage insulation, with a ceramic blanket against the shell lid, walls and floor, and a ceramic board as a hot face.

They all use machined burners... no exposed threading, for a more consistent flow and less "burnback" at the burner mouth.

The Knifemaker models have a floor which can be replaced in literally under 1 minute, for under $15. (great for welding applications)

 

So anyways, I was just curious. What are the "facts" which lead you to make the statement that these forges don't "cut it", especially in comparison to the other models you referenced? Or have we relied on the many varying opinions which are floating around the online community? I'm not trying to be a jerk, but an arbitrary statement like that, on a website like this, can lead to a negative view of my products by many potential customers. Out of courtesy, I would appreciate more information, at least to qualify the "doesn't cut it" verdict.

As a professional Blacksmith with a 23 year background in fabrication, welding and engineering, I have worked hard on these and have refined them over the last 5 years in an effort to make the most efficient, yet easiest to own and maintain forge available. I tried to correct the things I didn't like in the commercial forges available, while keeping the features which appealed to me as a working Smith. Nothing is perfect, and compromises must be made in an effort to get the most utility from a tool, but that is true in all things. Otherwise, we would have 50 models, each designed for a very specific task. But all in all, against the other forges mentioned, these will do everything they do, and do it just as well, for a lower price. When it comes time to reline you will really appreciate the thought that goes into the design, along with the cost of the relining materials.

Like I said, there are many opinions online, some valid, some based on pure ignorance. Heck, if we look hard enough online, we can even discover the "fact" that we never really landed on the moon or that the earth is really, in fact, flat! Anyway, the point is, this is the internet, and everyone wants to be an "authority" on some subject, (not directed towards you John) but the problem is, many of these "authorities" have no real knowledge of what they speak of. That leads the people who are just looking for information to, at times, draw some inaccurate conclusions. So in short, I do not mean to offend, and I am sorry if I have, but I simply wanted to clear the air, so to speak, on my behalf.

[John Martin]

I'm 14, I'm just trying to get setup and figure out what is right and what is cost effective, how does the two burner last on a 20# or 40# tank???

 

DBIron, I said this one doesn't seem to cut it, because I've been told that, I shouldn't of said that because I do not know that. But I am looking at yours or NC Tools. Most likely going to go with yours.

 

BTW, the zip code is 53094.

Edited December 9, 2008 by John Martin

[KPeacock]

DBIron,

 

Well said. I'm not involved in the discussion here and I am not in the market for any of the above forges, but I want to thank you for taking pride in your work and standing up for it.

[KPeacock]

I'm 14, I'm just trying to get setup and figure out what is right and what is cost effective, how does the two burner last on a 20# or 40# tank???

 

I recently built and tried about a half a dozen variations of venturi style burners and a few different forge body styles. In the end, I am running a homemade forced air burner with a blower from a gas laundry dryer. My wifes hair dryer failed after a few days of forging :-)

 

For me, it seems a lot easier to get the forge tuned the way I want it. I am now able to easily forge weld whatever I happen to be welding. This was not possible with some of my other configurations. I'm still tinkering with the venturi burners as I like the simplicity of them. Eventually I'll get one to work the way I want it to, but until then I'll continue to make parts and knives with an easy to use forced air forge.