raypa Posted October 27, 2008 Share Posted October 27, 2008 OK. so I made a replica gas forge from the plans on the site here. It is completed except for the kaowool (which im waiting for payday to buy). ANYWAYs. i firgured I would fire it up. It burns ok, but there is a very un burned propane smell. I'm running at 10 psi with a reg from a turkey fryer. I'm thinking I should close up the belled end a tad to allow it to burn more efficiently. ?? ray Quote Link to comment Share on other sites More sharing options...
raypa Posted October 27, 2008 Author Share Posted October 27, 2008 here are some additional pics The setup is 1/4" necked down to 1/8th" with a 1/32" hole drilled in the brass cap. Why am i smelling propane? Thanks in advance ray Quote Link to comment Share on other sites More sharing options...
NOS Posted October 27, 2008 Share Posted October 27, 2008 First thing is to take some soapy water and check all connections and hoses for leaks! Never take any chances with safety! If all of your connections are free of leaks, then start looking closer at your forge. What color is the flame? (is it mostly blue, or a yellow/orange color) Sounds like you are running too rich, which is mostly a blue color flame. Also how far out is the "Dragon's breath" from the forge? Try cutting down the pressure a bit say around 5 psi or so, and see if you smell it then. Then you can experiment with more/less pressure as will as more/less air until you get the desired results. Just my take on it anyway. I've had to do some adjusting to my forge to make it run more efficiently. If I'm wrong then I'm sure someone will correct me. I'm still a bit new, but that is how it was explained to me. Hope this helps Quote Link to comment Share on other sites More sharing options...
Rich Hale Posted October 27, 2008 Share Posted October 27, 2008 YOu need an adjustable regulater also did you use an existing design? and if you did did you make any changes to the plans? Quote Link to comment Share on other sites More sharing options...
Dave Hammer Posted October 27, 2008 Share Posted October 27, 2008 (edited) There is an odor associated with propane gas forges, even well tuned ones, but that distinct propane odor should not be there. I second checking for leaks first. The only time I have ever distinctly smelled propane is when there was a leak. Extremely dangerous. Edited October 27, 2008 by djhammerd Quote Link to comment Share on other sites More sharing options...
jimmy seale Posted October 27, 2008 Share Posted October 27, 2008 by all means... mix up soap and water and check all connections and the reg. too- it could be leaking, stay safe, jimmy Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted October 27, 2008 Share Posted October 27, 2008 That reduction does not look smooth and even and you will not be getting a good aspiration with it. You don't want any "ledges" like you have. I'd strongly suggest you rebuild the burner! Quote Link to comment Share on other sites More sharing options...
raypa Posted October 27, 2008 Author Share Posted October 27, 2008 I used the plans from the 200 section of this site to build it. The only difference is that I used reducers from the belled end because I couldn't find the 2" to 1" bell. I wonder it I could use RTV to smooth out the transition. I am getting a blue flame that seams to float out past the end of the burner tube when the pressure is up but doesn't leave the forge. I drilled a 1/32" hole in the brass cap for the nozzle. The other modification is that I did not hozzle the 1" pipe like in the directions because I didn't know how. I checked my connections and did not see any apparent leaks. Is there any other buner designs I can try if this one is going to give me issues? As far as lowering the pressure, I was under the impression that I would need to run at least 10psi to opperate the forge. Thanks for the help. ray Quote Link to comment Share on other sites More sharing options...
raypa Posted October 27, 2008 Author Share Posted October 27, 2008 YOu need an adjustable regulater also did you use an existing design? and if you did did you make any changes to the plans? The regulator is adjustable from 0-10psi. I found the plans on this site with the changes listed in my other post. What do you think Thanks ray Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted October 27, 2008 Share Posted October 27, 2008 (edited) Pressure you run the forge at depends on burner, altitude, backpressure, etc there is no One True Pressure to run at---you adjust the pressure until it runs right for what you want to do. (and don't forget most gauges can be radically off unless you have callibrated them to a known standard and that's only good until the next time you bump them...) You can make hacks to try to fix the ledge issue but you may be better off just getting a proper sized reducer to start with. Edited October 27, 2008 by ThomasPowers Quote Link to comment Share on other sites More sharing options...
raypa Posted October 27, 2008 Author Share Posted October 27, 2008 Well i am back home. I am going to try a 2"x3/4" bell with a 3/4 burner tube. I will post later with the results. How important is the fullered on the burner tube that is the blue prints? ray Quote Link to comment Share on other sites More sharing options...
Bentiron1946 Posted October 27, 2008 Share Posted October 27, 2008 I think maybe you need to hunt around for a "bell" reducer and not the "step" reducer that you have. I think that you maybe getting some back feed from that. Quote Link to comment Share on other sites More sharing options...
Ian Posted October 27, 2008 Share Posted October 27, 2008 Had a look at the pictures and a few thoughts. Yes that bell housing has a LOT of ridges on the inside, and compared to a commercial venturi (look at a car for instance) is VERY rough. Air likes smooth surfaces to 'flow' over. Get some chemical metal and smooth out the ridges. After you've done that and before you junk it best to know if you have the jet aligned correctly into the centre of the pipe as well? If it's not blasting gas straight at the burner pipe it won't be helping ANY and you need to sort it. Best way to do this is with water, use a hose and hook it up, turn it on high so you have a dead straight jet of water, then align that up dead centre on the burner pipe and lock it down tight. You now know the jet of gas is dead centre, try your experiments again and see if there's any improvement. BTW, if it moves you have to do it all again so make sure it WON'T, an accidental knock might have caused your issue in more ways than one. Also for this type of burner you need a burner pipe that's in proportion to the Venturi bell. Most folks use 3/4'' pipe or above. 1'' is a good size. The LENGTH of the burner pipe is important too, too short in relation to the bell and pipe diameter and it wont have time to mix well before its out the end and into your forge. Long story short a LOT of time and money can be spent creating the ideal burner unless your names John N (sorry John, couldn't resist, thats a LOVELY burner) READ through Ron Reils site, I did and my burner works well enough. Nuff said? Quote Link to comment Share on other sites More sharing options...
raypa Posted October 28, 2008 Author Share Posted October 28, 2008 OK. I built one with a new bell that goes from 2" t0 .75". I fixed the leak. Now i just cant get it to burn out the end of the tube. it wants to burn in the tube right off the nozzle.. (yes i know that is dangerous and i shut it down). Question. Is my 1/32" nozzle hole a good size? I'm thinking it may be too small to get good flow. I get it to burn at very low pressure, but at high pressure it is a flame out at the end of the burn tube. Ian, I will check out Rons site and see if it sheds some light. Quote Link to comment Share on other sites More sharing options...
peacock Posted October 28, 2008 Share Posted October 28, 2008 most all of the above advise is pretty good but one thing that has not been addressed is the fact that the inside of the forge may too large without the kaowool this type burner depends on back pressure to burn right. most of these will not stay lit outside the forge. if you have done all this other stuff allready you might wait till you get the koawool installed. if you just cann't wait reduce the volume of the forge with some bricks and/or clay dirt and close up the doors this will increase back pressure and may help your burner. also in pics it looks like your orrifce may be too deep in the reducer. move it as close as you can to the outside and you should increase your air speed thru the tube. hope it helps Quote Link to comment Share on other sites More sharing options...
raypa Posted October 28, 2008 Author Share Posted October 28, 2008 well, I'm going to give it one more shot and then buy a burner. I think my problem is just lack of knowledge about forges in general. Ive never seen one other than pictures on a website. Once I get the hang of how and why they work I will venture back into building the burner. No need to catch my garage on fire. I will be moving the jet back toward the rear as suggested to see what happens. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted October 28, 2008 Share Posted October 28, 2008 Trying to design your own burner when you are not throughly grounded in what works is generally a very frustrating endevor. Starting with a known good design and following it exactly or buying one is a good way to move forward. Quote Link to comment Share on other sites More sharing options...
NateDJ Posted October 28, 2008 Share Posted October 28, 2008 (edited) You do have a burner flare at the end don't you? it is required for the burner to work. also make sure there is no outside wind blowing around it when you try it or it will keep it from burning right. }===<~ should do it This flare will create a low presser area just outside of the burner tube and keep the flame at the far end. a pipe 8-12 inches long should be about right and a flare with about a 15* angle about 2 inches long should be about right. The gas nozzle should be placed where it will cause the most air to be sucked into the pipe as it blows down the tube. If it is burning inside the tube then the tube is either too long, too big around (+1'') the gas nozzle is in the wrong position or your flare on the end of the nozzle isn't right. You should even be able to get it to burn right with out the bell end but you would have to hold the nozzle with pliers and that would defeat the purpose. Edited October 28, 2008 by NateDJ Quote Link to comment Share on other sites More sharing options...
cwilliams Posted October 29, 2008 Share Posted October 29, 2008 Yep you need a burner flare, you can buy a stainless burner flare for your 3/4 pipe off of either Ron Reils site or maybe it was Ellis knifeworks. Without it you will just keep chasing your tail. I had the exact same problems you are having until my flares came in. Chris Quote Link to comment Share on other sites More sharing options...
raypa Posted October 29, 2008 Author Share Posted October 29, 2008 Well, there is something to be said about the size of your orfice. I had a 1/32 drilled in my endcap. I overdrilled that with a 1/16 and bada-bing a functional burner. I could not go over about 4 psi with out a flame out. Not an efficient burner, but a functional. Once it worked, I did add a make shift burner flare end using a 3/4 copper fitting to see if that helped and it did. So I chopped the 3/4 nipple down to about 6" then added a 2.5 in steel flaired end to it. Well, i lost performance. I was able to jump the pressure to 10psi but the flame was very erratic and had an ugly pattern. I'm going to try another 12" 3/4 with the end flare i made to see what happens tonight. Ian, thanks again for Reils site that is helping the learning curve. Nate, i will try to refine my flaired end with your recommendations. Heck, maybe I will have this thing working before i find an anvil. Ray Quote Link to comment Share on other sites More sharing options...
NateDJ Posted October 29, 2008 Share Posted October 29, 2008 the 2.5 in flare is WAY too big! The one I use is a 1'' pipe hammered over the 3/4'' pipe and then drifted out flare shape on the horn of my anvil. It is about 2-3'' long from the tip of the 3/4'' burner pipe. Quote Link to comment Share on other sites More sharing options...
forgemaster Posted October 29, 2008 Share Posted October 29, 2008 Hi All I thought being blacksmiths you would have made your own reducers from 2" pipe. Cut a piece of pipe long enough to handle, heat it up and swage the end down to the smaller dia you want to use, you may have to use a few sizes of swages to get it down without crimping the end. If you do end up getting a crimp just drift it out to remove the crimp and then start swagin again. Once I figure out how to post pickys on here I will post some showing the end result and if anyone wants a step by step photo. Swaging them down leaves a nice smooth radius inside, no weld joints, and if they burn out in a years time you can just make some more. Simple. Quote Link to comment Share on other sites More sharing options...
Mulciber Posted October 30, 2008 Share Posted October 30, 2008 I bought a book purely on gas burners for forges and kilns. Go to your local book store and see if they have it in stock. Authors name is Michael Porter. Seems to me that the entire collection by Skipjack press is worth owning. I especially like the new edge of the anvil. Gas Burners for Forges, Furnaces & Kilns by Michael Porter ...Skipjack Press Also, I try to balance my time for things that I enjoy doing. I probably wouldn't spend the time building a burner since they are fairly cheap to begin with. My opinion I don't want to save pennies when I can be making dollars. Although when I last looked he was selling for 30 and now they are 42$. Anyhow!Zoeller Forge Home Page Gas Forge parts, Atmospheric Burners, and Blacksmithing I admire your tenacity and hope you get your forge done soon! Quote Link to comment Share on other sites More sharing options...
sfDuck Posted December 15, 2008 Share Posted December 15, 2008 I am a number 1 muti certificate holder for nat gas, propane, and oil. It means I can work any gas any size. But that is just the theory of how its supposed to work. Unless you have experience working in the field you can get lost real quick! Oh, and I forget stuff sometimes, so you do have to be careful, but thats cause I'm old TOO. IF I had to manufacture fuel lines I had to use (Approved Materials and Methods) if I didn't and someone died because what I did I went to jail. So I suppose all you fellas who built your own fall into that dark hole. BUT I could make any thing that held feon out of copper tubing or brass welded together with silfos or silver solder and they witheld pressures more than 300 lp. without leaks. Hmmmmm. Leak testing with dishsoap and water or store bought stuff was a given on everything made or ajusted and on bigger stuff they required a 24 hr press test at a set pressure. Get a reg that is ajustable and after the leak test is assured start with a very small pressure and see how it runs. every piece of equipment is different even in small ways and careful testing is needed. But when the flame is not sitting just a fraction from the burner or lifting off , your press IS TOO HIGH! And without a proper vent for the burnt gases to go to IT WILL SMELL!!!! Thats why kitchen ranges are limited to below 80 thou btus without a range hood with a sprinkler system to remove the burnt gases, like the ones at macdonalds. But theses are just the mussings of an OL" Fart Quote Link to comment Share on other sites More sharing options...
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