Well, I think I’ll try something new and try doing something the right way the first time and NOT waste a bunch of time and cash… To that end I am going to try to line out a materials list and put forth a couple questions I have been unable to answer scouring the forum here and the plans I have downloaded.
A little background on me, I’ve built a couple gassers that worked fairly well over the last few years but currently (multiple moves recently where some stuff just didn’t make it) don’t have a forge. I have a fair few tools of various qualities and a little experience in a lot of different stuff. Specific to this project I have a buzz box welder that my very limited skill set can make work.
My goal in this is to build a propane forge that will allow me to work basic techniques until…well I outgrow it. I’m a cheap/broke hobbyist so I don’t need anything commercial quality and I enjoy the building side almost as much as the using so I don’t want to buy a manufactured one. I use a fair bit of reclaimed steel so I want something large enough to get odd shaped pieces reformed to bars that I can use (think opening eyes in leaf springs). In a perfect world (and this seems reasonable) someday I will start doing some forge welding practice and this forge should allow me to start. I figure that about the time I need to reline the forge, I may consider a new design.
My intent is to use a 20# propane cylinder as the body and follow Wayne Coe’s design. I am currently planning on firing it with a pair of Frosty’s T burners run off a 100#er I have. I already have a regulator that I’ve used in the past with good results.
As I said, this post is to try to consolidate thoughts and pose a couple questions. I apologize beforehand if these have been answered elsewhere on the forums; I have literally reviewed them for hours. (I work a job where I have a lot of time on my hands to do so). Some of my questions are more… academic as I am stuck planning at the moment and am curious more than anything.
Let’s start with the burners (parts to make 2)
1"x 3/4" black iron plumbing T (2)
¾" x 6" black iron nipple (2)
1/8" mpt x ¼" flare fitting (2)
0.035" Tweco mig contact tip (2)
1” x 3” black iron nipple/pipe (2)- I intend to use these to mount my burners to the forge body. I have had good luck in the past thinning the outside of my nipple and reaming out the inside of these to make a tight slip fitting. I will weld these to the body and tap them to take the ¼” x 2” bolts to lock the burner in place
¼” x 2” Bolt (6)
Only question I have on the burner is this: I have seen references to cutting down the Tweco. Is that to ensure the tip sits 0.5XD from the end of the burner tube? I assume I’ll need to decide if that is needed during tuning, correct?
I have a working idea for my gas supply plumbing that goes from each burner to a length of copper pipe, then the regulator or needle valve (my plan is to use one of each though I might have a second regulator in my stuff) then to a T, a shut off valve, then to my rubber supply line coming from the tank.
With regards to plumbing, is the needle valve adequate to isolate my second burner or do I need another valve? My thought was when running just one burner to use the one at the rear but should it be the one closer to the door? I had also planned on welding a support arm to the forge body to secure the plumbing to, well away from the body itself. Is this a terrible idea?
For the forge itself, I need:
20# propane cylinder for the body (1)
Ceramic blanket (planning to buy Inswool from Wayne)- If my math is correct, the inside circumference of this cylinder is 39” and should be around 20” long if you include the ends. Figuring extra for the bottom, (5 linear feet)
Castable refractory (Kast-o-lite 3000 or what I can get locally) (15 pounds)
IR reflective (Plistix or what I can get locally) (1 pint)
Fire brick for floor and end closing (have several on hand)
Regarding the forge, should I expect 1 pint of IR coating to do this or do I need to plan for more? Once the lining is in place, how thick will the walls of this be? I am trying to get an idea of what my finished volume will be (Wayne mentions 583 for a forge this size but is that shell only or shell with liner in place?) Also, I don’t have an oven to ‘kiln dry’ the castable as Wayne suggest. I’m in the Portland, OR area so humidity is going to be high no matter what. My thought was a few days with a candle or two inside it well buttoned up then a long low run with one burner turned as low as I can get it for several hours. AM I setting myself up to fail or is this a reasonable solution?
With this setup, should I plan to be able to do basic forge work (not welding) with a single ¾” burner and just kick on the second for bigger stuff/welding or would I be better off installing a pair of 1” burners? I know this forge is probably on the larger side (isn’t that a requirement for us new guys, overbuild the forge?) but I figure I will add bricks if needs be to decrease the working volume.
I hope I am not being too redundant with this line of questioning but your seasoned input is appreciated.
And I also very much want to thank the guys around here that put so much time and effort into sharing their experience and knowledge with the rest of us.