Fired up my Blacksmithing forge tonight!!!

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Let there be fire!  Been working on this for months.  It's propane powered.  I have a slight amount of tweaking to do but just about ready to pound some iron.
Reply:sweet.very sweet.now show something cool, you make with it.Brian LeonardAppalachian Ironworks L.L.C.434 Long Branch Rd, Marshall, NC 28753828 649 9966828 702 [email protected]
Reply:Very impressive.What sort of pressures etc.?
Reply:Nice work. keep your metal in till it turns a bright yellow,your arm will thank you for it.FelonCaution lurker lives here" hmmm That is serious,pass the ganja and pick up a  24 of MGD"
Reply:app-ironworksllc--you bet will be pounding soon. Billy and Felonyass Monk--I am running 6 PSI this seems to be the optimum pressure.  I have not got the venturi effect tuned in just exactly yet, it is a two burner forge and I believe it is going to be a matter of experimenting with the distance I place the jets.  One side appears to work better than the other.  I am using MIG tips, 0.030.  Here's what the contraption looks like:
Reply:Nice work.  Are those blocks "fire" proof?Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:Lugweld--they are the one in the forge is rated at 2600 degrees and the ones outside are rated to 2300 degrees and they are junk.  They are light weight, cost an absolute fortune and won't last.  I need good old fire brick that's solid.  The thermal expansion will kill these light weight jobs, if you look at them sideways they will crumble before your eyes and if one was to drop, you might as well go get the dust pan.
Reply:You can get castable (High temp cement) that will hold up for a long time. The firebricks you are using are like the ones in a kiln, designed to reflect the heat back into the chamber. The heavy more solid ones absorb heat and will hold it for a long time, much better for a forge.
Reply:If your area is like mine, there are many old chimneys around worth taking down for the old fire brick.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:That's cool!  I have an old forge, hand-crank bellows, Peter Wright anvil and assorted antique tools that were given to me several years ago.  I haven't done anything with them yet, except the anvil.  I beat on that once in a while.  I'm interested to see what you turn out with that thing.Work HARDER, not smarter! ------------------------ Miller Bobcat 250Millermatic 251Lincoln Precision TIG 185Hypertherm PM 600Hobart 135 HandlerOxweld 400 FlameMaster
Reply:Great looking forge.  I'm working on a propane forge myself ( I have a coal forge) and have a couple of questions.  How do you get enough air mixed with the propane to increase the heat enough to forge.  The forge I'm building requires an external air source - typically a small squirrel cage blower.  Below is a photo of the type of forge I'm working on.  This forge was designed and built by a local bladesmith (in the photo).  I watched him make a couple of knives and also watched him as he taught others.  According to him a 20# tank will pretty much last all day.  The back of the forge (7" steel pipe) has a removeable cap - when removed the forge will accommodate any length stock.  How do you regulate the pressure? (regulator not pictured?).
Reply:reefera4m--here are a few more pics that will give you an idea of the gas setup, it runs at 6 PSI with a regulator, through the Venturi Effect you get the air mix.  this would not be  a good forge to forge weld with, the flux tares up the Insowool insulation.  If you did you would just need to watch the flux.  A barbecue propane tank will run all day.  Let me know if you have other questions.
Reply:Very nice work, nice pipes. On your Venturi it looks like you have used mig tips, or are they a special item?
Reply:Sorry I didn,t read properly, yes to mig tips. Good idea, I think I can read 1/8 on the elbows.
Reply:Thanks for the info - and the photos.  I think I get the idea.  I really like the venturi design, eliminating the need for a blower would be a major plus.  No need to buy a blower, better portability (several of my friends get together to forge occasionally), and no need for external power.  Did you machine the venturi throats and the tip adapters or are they something I could buy?  I'm not a machinist nor do I have access to a milling machine so making them might be a challenge.  I also like the mounting design - should allow for easy tweaking of the nozzle position.  My friend, the bladesmith, suggested that in addition to moving the nozzles you could try different size nozzles - say a .024.  He experimented with various sizes and found that smaller worked better.He also uses KOAwool and it seems to hold up pretty well.  Maybe just a different name for the same the thing though.  Same trouble with firebrick - it eventually breaks down/burns up.  I might try BW's suggestion for the cement.Another pic:
Reply:reefera4m--May I suggest a great book that would be worth the purchase, it is called Gas Burners for forges, Furnaces & Kilns By Michael Porter.  Amazon has it:[ame]http://www.amazon.com/s/ref=nb_ss_0_12?url=search-alias%3Daps&field-keywords=gas+burners+for+forges+furnaces+%26+kilns  &sprefix=Gas+Burners+[/ame]May I also suggest you check out this web site:http://www.zoellerforge.com/I have no connection to this fellow, I have however bought parts and I believe his prices are very reasonable and if your time is worth anything this can be a one stop shop for all you need.  I learned the very way hunting this stuff down.  The other spot you need to check out is:http://www.iforgeiron.com/forum/Like the guys on this site, these folks rock, and will help with questions and problems. Check out the specific forum for forges.This Venturi deal I have could be fabed up without a machine shop, it is basically 3/8 pipe.  I don't know I would go down the road of these burners I built if I had to do it all over. I was following what worked well in a blacksmith class I attended.  I would consider using either a purchased burner or making one like the one shown in the book above.You will find that you do not need a blower, these babies will go yellow-white hot enough to forge weld with.  If you do like this design and decide to go with it, let me know and I can machine up the 3/8 plug to accept the MIG tips, a lathe makes life easier.  The chamber you could weld up from pipe which is what I did, I just cleaned it up with the lathe.  Hope that helps let me know if you have any other questions, best wishes for success in your build.
Reply:reefera4m--here is another excellent description of a forge build:http://www.arscives.com/bladesign/forge.tutorial.htm
Reply:200mphbusa,I'm defintely headed down the road to build one of these forges.  How did you make the venturi cones?  I think I can pretty much do all the rest but the cones have me stumped.  They look as though they might be milled from a chunk of bar stock.  Is the inside diameter consistent, i.e. the same throughout, or is it funnel shaped to give more of a venturi effect?  I appreciate the info.Thanks
Reply:Reefera4M--it really nothing special, just a piece of 2.5 inch OD tubing 0.150 wall thickness that I pick up from my local steel yard.  I turned a plug for the back end on my lathe, welded it in drilled a hole for the 3/4 inch black pipe and then welded the pipe to the tubing.  Nothing special inside just took the burrs off and chamfered all the edges.  Here's a couple of more photos. I would however suggest you consider the black iron pipe fab up that is described in the book referenced above and on some of those sites.  Its a faster build and easy, no lathe needed just a little drilling and taping. Holler if you have any more questions.  Good Luck!
Reply:Originally Posted by 200mphbusa
Reply:Steve--yes the first was a dry hump fit up without the Rectorseal (pipe dope for gas pipe).  In reality from the valve on it's not a "closed" system, the tips are alway open so to speak.
Reply:Looks awesome!
Reply:One final question.  Why did you choose to go up vertically with the w 3/4 pipe and then angle 90 degrees to the venturis?  Why not just come out from the side horizontally?  I'm sure there is a good reason - I just can' figure it out.
Reply:Refera4m--wish I could tell you there was a scientific reason or engineering design that caused that 90 ell but I can't.  It was design that I copied from a blacksmith class.  I have since learned through reading and studying other designs that the recommended practice it probably better to run the burners in at an angle so as to not cause what it called the chimney effect where the heat rises back towards the burners.  This is the theory.  In actuality these babies get hot no matter where the burner is located.  May I suggest the investment in the gas burner book recommended above, you'll find a ton of valuable info and in the long run it will help you build the best forge and get it to the hottest temps. Let me know if you have any other questions.
Reply:I am sooooo jealous of you guys!This is my favorite thread on this site.The pics are awesome and so is all of the great info.I can't wait to build my own forge and hear that anvils ring again.Thanks a ton and have fun.cheersTalent is a flame. Genius is a fire.- Bern Williams200mphbusa,Please check your private messages.Thanks
Reply:200ampbusa - Thanks for posting this great little forge.  Your great photos and descriptions were more than sufficient for me to replicate this forge!  And if I can do it anyone can!After a little 'tweaking' I was finally able to get my 'cookin' - heated up an 18" piece of 5160 OFS (Old Ford Spring Steel) to critical (non-magnetic) in just two minutes!  I pretty much copied the forge you posted.  I used a 12" lenght of 8" diameter steel pipe as the forge body, 3/8" black gas pipe to the nozzles and 3/4" black pipe from nozzles to forge.  For the venturis I used some 3" lengths of 2" diameter exhaust pipe (my boys used to practice on scrap exhaust pipe donated by the local muffler shop),  MIG tips for nozzles.  For the propane hose/regulator I used an old REGO 567EB propane regulator that had a soldering tip which I preplaced. The only tools I used were a Miller175 MIG Welder, 4" grinder with cutoff wheels, pipe cutter, pipe theader and tap plus pipe wrenches to assemble.  Total cost of material less than $20.Thanks again!Here's some pics:Forge:
Reply:reefera4m--Outstanding!  You have that nice and yellow hot!  You are definitely cooking! you'll have to post a few knives or other projects that you make with it. Nice job!
Reply:200mphbusa,I received a suggestion from a knifemaker on a way to make this design heat a little more evenly and thought I'd pass it along.  Positioning the burners at an offset is supposed to cause the heat to swirl around the metal being heated rather than directly on the metal.  I'm going to try it on my next one and if it improves performance, redo the original.  Best thing about this modification is that it doesn't require any changes other than the positioning of the burners.Sketch:
Reply:Reefera4M--I believe that is a very good idea and recommended by others.  I will do the same on the next one. Any time you can get the steel hotter its less work on you to get it shaped, plus you probably end up saving on the propane.
Reply:With your current designs you should consider adjusting the height of the material you are heating.  There is a optimal point where max heat will be provided.  If you look at your part if it is too close to the burner, then the point directly under the burner will be darker than the surrounding area.
Reply:After receiving lots of positive feedback and some great ideas to improve the propane venturi forge design I decided to incorporate some changes and see if they would make a difference.Well, they did - all good.  I first took a design feedback from another Forum  (see prior post) and thought 'what if I not only offset the burner but placed them on opposite sides'.  I wasn't sure how the difference in the length of the burner pipes would affect the performance but figured the only way to find out was to try it.  I also positioned the burner ports equal distance from each end.  It actually worked great!  No, make that better than great.  This new forge 'Propane Venturi Forge II' heats as fast as the original but much, much more evenly!  The offset/opposite sides really create the swirl effect.  If I elevate/suspend the steel so that it's in the middle of the forge it gets little or no direct heat.  I plan to someday rework the original but for now I'll use it for the rough forge/welding work and #2 for the heat treating.  New step is to line the forge with the refractory cement I purchased.I also made a couple of stands for the forges - 1 1/2 pipe 32" long.  Couplings are welded to 1) old lawn tractor wheels and 2) bottom of forge support.  I can disassemble the forge into four easily transportable pieces, the forge body, the propane tank, the pipe stand and the wheel base.Thanks again 200mphbusa for the original idea!Here's the pics.  To light out to photograph the forge in operation - I'll try to take some pics tonight.
Reply:great stuff... but you;ll miss the carbon in your steel unlike a traditional pit right?Unit in my fab shop dept:my good hand and team that trust me...A lone welder make art... a village full of welder make Miracles...
Reply:Carbon migration is minimal and a propane vs coal will not make a difference.
Reply:Couple of modification/enhancements to the original design.Sliding, extendable blade/tool rest.  This, along with the fire brick on the 'porch' allows me to position the work piece where I want to and where it will heat the best.  The rest can be used to support the work piece on either or both ends with a maximum extension of about 24 inches beyond the 'porch'.  Completely removeable for transporting.Rear cover - opposite side hook faces up so that I can just give it a twist to remove,  It fits snug on the lugs and snug to the back.  Helps retain much more heat than an open back but is removeable for longer blades.The burner flames using the new offset design.Tried to get the swirl but doesn't show up in the photo well but heat pretty evenlyAfter 2 minutes:Last edited by reefera4m; 12-24-2009 at 02:39 AM.