Jeff Lamm

Help me figure this forge out?

26 posts in this topic

G'Morning!  Long story short, my FIL made this forge for me back in 2005.  Same year I was in a crippling car accident, and I haven't been able to use it until now (It's been a LONG recovery).   Anywho, I finally set it up, and I'm not really sure it's ready to light.  So I'm posting these pictures of it for you lot to look over and tell me.  My primary concerns are as to whether it needs a pressure regulator/gauge to run off a standard BBQ propane tank, and if that hole on the end of the feed pipe needs to be closed off.   Right now I'm back to using a single firebrick forge, and as happy as I am to be forging again, I'd really like to use the big forge at the grown ups table, if you know what I mean.  I'm open to all kinds of input, suggestions and insults, so go for it.

Forge3.jpg

Forge4.jpg

Forge5.jpg

Forge6.jpg

forge7.jpg

forge8.jpg

Share this post


Link to post
Share on other sites

Hi Jeff

I am certainly far less experienced in this than many of the people who will no doubt be along shortly with input but from what I have read on here and what I see in your pictures the answer to both questions is almost certainly YES

Welcome back to forging though and I suggest you hang around for a few more replies before lighting up :) then go for it have have fun

Dave

 

Share this post


Link to post
Share on other sites
48 minutes ago, EnglishDave said:

Hi Jeff

I am certainly far less experienced in this than many of the people who will no doubt be along shortly with input but from what I have read on here and what I see in your pictures the answer to both questions is almost certainly YES

Welcome back to forging though and I suggest you hang around for a few more replies before lighting up :) then go for it have have fun

Dave

 

Thanks Dave!  Yes, as anxious as I am to play with my big boy forge, I'm in no hurry to blow myself up. (again.  Long story, have the scars.)

 

Now that I've found this place, I'll be around for a while to come.

Share this post


Link to post
Share on other sites

A 0 to 15 or 0-30 psi regulator is a very good idea to get a stable gas flow even if you are doing fine tuning with the valves at the burner.  (which seems a strange set up...)  the end of the fuel tube *MUST* be closed or there will not be pressure to feed the burners.

Share this post


Link to post
Share on other sites
1 hour ago, ThomasPowers said:

A 0 to 15 or 0-30 psi regulator is a very good idea to get a stable gas flow even if you are doing fine tuning with the valves at the burner.  (which seems a strange set up...)  the end of the fuel tube *MUST* be closed or there will not be pressure to feed the burners.

I concur it's a weird set up.  OTOH, if you'd met my FIL, it might make more sense.  He's.....unique.  Still, the workmanship is very good, and he did give it to me as a gift, so.....

 

Got the butt cap for the pipe, and I'll get the regulator as soon as funds allow.   SO looking forward to playing with a bigger, hotter forge.

Share this post


Link to post
Share on other sites

I am in the UK so can't answer for the "standard BBQ Propane tank" question, but I strongly suspect the answer is yes. Over here, most BBQs run on fixed low pressure (35 mbar, 14" WC) regulators and the cylinder fitting for these is different to that for the high-pressure regulator needed for most gas forges.

The pics are not very clear: what is the discoloration on the pipe half-way between the open end and the nearest burner? It could be that the pipe has a welded blank in there. Easy way to check is to poke something down the end and see if it stops there.

If it's not blanked already, it needs to be.

I'd be inclined try to arrange some sort of support for the pipe or the burner feed lines to take the strain off the spiders in the burners. If there's any movement that shifts the gas jets out of alignment with the center of the intake bells, even slightly, it will change the air:fuel ratio and make tuning trickier than it needs to be.

 

Share this post


Link to post
Share on other sites

Question: did he try to run weed burners down the burner pipes for the burners?  What kind of orifice do those burners have?

Share this post


Link to post
Share on other sites
1 hour ago, timgunn1962 said:

I am in the UK so can't answer for the "standard BBQ Propane tank" question, but I strongly suspect the answer is yes. Over here, most BBQs run on fixed low pressure (35 mbar, 14" WC) regulators and the cylinder fitting for these is different to that for the high-pressure regulator needed for most gas forges.

The pics are not very clear: what is the discoloration on the pipe half-way between the open end and the nearest burner? It could be that the pipe has a welded blank in there. Easy way to check is to poke something down the end and see if it stops there.

If it's not blanked already, it needs to be.

I'd be inclined try to arrange some sort of support for the pipe or the burner feed lines to take the strain off the spiders in the burners. If there's any movement that shifts the gas jets out of alignment with the center of the intake bells, even slightly, it will change the air:fuel ratio and make tuning trickier than it needs to be.

 

It's a weld.  I found it curious myself, and just checked it.  Good catch, he welded it so the pipe is closed.  I didn't think to look down the tube and see, I just assumed it was open the length of it.  Why he left 2" of open pipe at the end is beyond me, however.  I'm going to thread the end and cap it anyway, just in case there's a small hole or one ever develops.

I do have support for the spiders already built (It's a pile of hard firebrick), and admit it's kind of a goofy looking set up.

 

It's a weird setup, but it was a labor of love for his son in law, and I'm inclined to make it work for that reason alone.

1 hour ago, ThomasPowers said:

Question: did he try to run weed burners down the burner pipes for the burners?  What kind of orifice do those burners have?

Not sure.  He just gave me this thing as a gift at some point, and then between my injuries, recovery, moving and his falling out with the family, I never got details or have contact with him.  So I'm going by guess and by gosh.  In addition, he also gave me a giant trashbag with a huge roll of Kaowool.  I'm guessing to replace the lining inside the forge.

 

At some point, I'm going to get the regulator and set the crazy thing up, give it a go.  From a safe distance, of course.  Before that I'll see if I can get the top off and get a picture of the interior ends of the burners.

 

Wacky looking thing, isn't it?

Share this post


Link to post
Share on other sites

I keep remembering the line about shoes: "They looked like they were made by someone who had read a description of shoes but had never actually seen them in person."

Share this post


Link to post
Share on other sites
2 minutes ago, ThomasPowers said:

I keep remembering the line about shoes: "They looked like they were made by someone who had read a description of shoes but had never actually seen them in person."

Apropos.  He was an electrician and welder by trade, don't know that he'd ever seen a forge before.  Still, all things considered, I think he did an ok job.  I hope.

Share this post


Link to post
Share on other sites

When you take a look inside the burners, pay careful attention to the jet arrangement. It's worth having calipers and a thread gauge handy so you can measure the threads if the jets screw in. A set of number drills would also be useful to use as go/no-go gauges to measure the orifice size in the jets. Cheap import ones are fine and 50-80 should cover the range you are likely to want. They can be used by hand with a pin chuck to open out jets made from brass or Copper (MIG tips are copper. Most commercial gas jets are brass).

Pretty much any Naturally Aspirated burner can be made to work if you are able to tune it by changing the jet size. 

 

Share this post


Link to post
Share on other sites

Tim, will do.  I'm taking the top off today, weather permitting.  I'll get what pics I can.  Right now I'm praying it even HAS jets, and doesn't feed gas right into the chamber.

 

Addendum:  What kind of risk would ensue if I ran a test burn, as is?

Share this post


Link to post
Share on other sites

OK, got images of the interior lid and jets.  That's as close to the jet as my phone will focus, so sorry if it's not tight enough.  Tell me what you think.

 

Forge9.jpg

Forge10.jpg

Share this post


Link to post
Share on other sites

Welcome aboard Jeff glad to have you. If you'll put your general location in the header you might be surprised how many of the Iforge gang live within visiting distance. IFI has something like 40,000 members spread around about 140 countries, we're a global community.

I started to reply yesterday but Deb and I went for a cruise before I finished.

Just set it up away from everything ad light it up, you'll know if the burners work correctly immediately. Till you give it a test burn don't worry about jet sizes, position, alignments, etc. That's for it if doesn't work as she sets.

Now for what I started writing yesterday.

I have a couple issues with your forge, good first.

The burners look to be commercially made so shouldn't need the kind of tuning home builds need. Light em up and see. Put a bit of burning paper in the forge and crack the valve open till it roars or is belching yellow flames.

The angle between the burner and forge's burner ports looks good, smooth 45s are generally not disruptive to burner performance.

How comes the problems I see in the pics. The steel supply lines coming off the burners is WAY too long it WILL knock the gas jets out of line. Worse they're a safety issue, even a small bump, say dropping something on the propane hose can cause a break at the burner fittings. That is where all that leverage is concentrated. Then the propane hose is hanging on the manifold.  Not good at all. Scrap that almost completely. Built by someone who doesn't know much about burners we see it all the time.

Put the manifold pipe as close to the burner fittings as possible and threaded 1/4" pipe will work just fine, it'll supply more than enough gas. I T the main supply into the center between the final supply lines.

Short fittings on the burners, NO more than 2" nipple off the burners, MAX. 

Put a 1/4 turn ball valve on each final supply at the manifold. 

The manifold connects to the rubber propane hose from the tank.

0-30psi regulator on the tank, the BBQ regs can't supply the psi nor the volume necessary to run a forge burner of any size. Put the pressure gauge on the regulator, there's a fitting for one. Forget what OTHER guys run their burners on there are too many variables for THEIR settings to make much difference on yours. The gauge is for fast repeatability in your forge so you don't need to tune by ear and eye when you want to do a different process. For instance bending light stock doesn't need yellow heat, mid orange is plenty but if you want to weld you want screaming hot. If it's a thick billet you  might want to preheat at a lower temperature for a longer time so the heat penetrates the entire depth of the billet. THEN turn it to high yellow. Anyway, a gauge lets you make precise changes without guessing.

Another 1/4 turn ball valve between the regulator and hose is a good safety measure if something goes wrong you can shut off the gas in fractions of a second even if you have to reach through the flames. Or you can throw a rag at it. It takes a couple few seconds to shut off the gas at the tank valve and it may be more time than you have.

The below pic shows the 4 burner manifold on my soon to be retired shop forge while it was under re-construction in it's second iteration. Do NOT build a forge this big or versatile I never use more than 2 burners and mostly only 1, the number and selection runnning is easy with the 1/4 turn ball valves on the manifold. The rubber propane hose is kept far from the fire and the 100lb tank blocks that side so nobody NOBODY tries to walk between the tank and forge so the hose is protected from folk tripping or dropping stuff on it. It also puts the tank about 4' from a broken fitting fire on the forge so it's fast easy and safe to shut off in a hurry. 

I like copper final supply lines if the burner is above the forge all 4 of the ones in the pic are now heat patinaed to the top turn and old penny colored to the manifold. When you shut a forge like this off the oft 2,600f+ temp chimney up the burners so precautions are called for. Either block them off or design the final propane supply to be heat proof.

Frosty The Lucky.

59188c0851e2f_VV1806.jpg.6caeb5bd0706a54b131b0ad7df13abe7.jpg

 

Share this post


Link to post
Share on other sites

Thanks for the input, Frosty.  The more I look at this thing, the more nervous it makes me.  For the life of me (possibly literally), I cannot imagine why he made those steel supply lines so damn long. 

Having blown myself up once before (2nd, near 3rd degree burns to both forearms from a gasoline explosion), I'm in no great hurry to have it happen again.  Ever.

I'm going to put using this thing on hold until I can do mods you recommend.   I do intend to do some forge welding (I've got a big pile of wire rope I'm dying to try making wire Damascus with), so this Frankenstein's monster of a forge has to work efficiently and safely.

Thanks for all your input , gang.

 

Just for FYI, I got my knifemaking start working for Randall,  and I've been hooked ever since.  My passion is to make big blades, Bowies, Kukris, axes and swords, but right now, since I can only work on small stuff, I'm concentrating on Kiridashis, neckers, straight razors, and such like.  It's been 12 years since I picked up a hammer, and it's good practice for my atrophied skills.

Share this post


Link to post
Share on other sites

You should be able to check the burn without fear of explosion.  Have a light chunk of paper in the forge and turn on the gas at the tank several feet away.  If the burners light in just a couple of seconds you are good to check them out.  If they don't turn off the gas before enough builds up to cause problems.  I get to relight the pilot lights on our 50 year old propane kitchen stove on a regular basis, as well as my 3 propane forges.  If you don't let unburnt gas build up  there isn't a booomfff problem.

Share this post


Link to post
Share on other sites

Jeff: Be cautious by all means but propane is nothing like liquid flammables. Those scare the blank out of me, they stick. Propane just breaths fire on you it can be bad but you can get away. 

Just hook that thing up out in the yard, stretch the hose back. Put a piece of burning news paper in the forge go back to the tank and open the tank valve slowly. If something bad happens turn it off, it can't, CAN NOT, shoot flame  more than a couple feet without you seeing it and shutting it off.

I understand gun shy Brother it happens to us all. I no longer cut fire wood, the chain saws just sit there. 

I believe there are needle valves on the burner fittings, make sure they're open about 1/2 turn and do not turn them off hard it screws up the valve seats. If the burner flames are yellow, weak and sputtery open the needles a little at a time, say sneak up on 1/4 turn per adjustment and listen to the flame. When they start roaring step back a little and look at the flames.

Heck it just occurred to me while I was heading for the submit button. If those are needle valves, close them. Open the tank valve and spray the hose and fittings with soapy water, Do a leak test.

Naturally aspirated burners aren't usually quiet and some can be heard a long way off. The ones on my forge are really loud you have to shout to be heard when even one is running. Don't expect loud but expect it to have a voice, it's like adjusting an oxy, acet torch at one point it's making orange fluttery flame and almost silent, start cracking the oxy and it turns clean, blue and roars.

It's just a tool Brother, take care but respect it don't be afraid of it.

Frosty The Lucky.

Share this post


Link to post
Share on other sites

You know, I didn't even think to do a leak test.  Brilliant idea.   And I plan to respect the heck out of it, lol.  I may even call it in the morning.

 

Fortunately, I live far enough out in the country that a growly forge shouldn't bother anyone.  I've got both a CO2 extinguisher and large buckets of sand and water on standby.   We're under constant fire warnings here in Floriduh lately, so I don't take chances.

Share this post


Link to post
Share on other sites

Well...while you are changing around all that plumbing PLEASE move those needle valves further away from the burner's air intakes; that is completely nuts!!!

Share this post


Link to post
Share on other sites
4 hours ago, Mikey98118 said:

Well...while you are changing around all that plumbing PLEASE move those needle valves further away from the burner's air intakes; that is completely nuts!!!

Yeah, that has to be an adaptation from a propane torch or similar. 

My Turbotorch needle valve is really close to the jet too though it's an ejector. If I took it apart and tried to make a linear burner out of the parts it might look something like the one pictured.

Frosty The Lucky.

Share this post


Link to post
Share on other sites

I'm chinking your torch isn't subject to chimney effects after shutdown, like that burner is.:wacko:

Share this post


Link to post
Share on other sites
9 hours ago, Mikey98118 said:

I'm thinking your torch isn't subject to chimney effects after shutdown, like that burner is.:wacko:

Not unless I set things up for it to be a chimney.

If I were going to use those burners I'd have to mount them in the side of the chamber with the angles pointing the valve, hose, etc. down rather than on top of the forge.

Frosty The Lucky.

Share this post


Link to post
Share on other sites
On ‎5‎/‎19‎/‎2017 at 3:25 PM, Mikey98118 said:

Well...while you are changing around all that plumbing PLEASE move those needle valves further away from the burner's air intakes; that is completely nuts!!!

I have no idea what this means.  Can you use the picture to explain?

I'm not really that stupid, it's just been a long time with a lot of injuries, and I've forgotten a lot of terms and details.  Honest.

Share this post


Link to post
Share on other sites

I'm no longer competent to judge who is stupid, or who is smart, about my subject. Becoming an expert has separated me from that prerogative; it's one of life's little jests.

Okay, the problem is the "chimney effect." Your burners face vertically down into the forge, from its top. The minute one or both burners is turned off in the heated forge, it's super-heated atmosphere will start using the burner  opening as an exhaust port. The burner will then super-heat, because it has no choke that can be closed to prevent it from becoming a chimney. At this point very hot gas will flow all around your valves, on its way out of the forge--overheating them.

Lots of burners don't become chimneys because they are positioned pointing slightly upward of horizontal in a forge, or are place horizontally near the bottom of a casting furnace; others have chokes that can be sealed close; still others have metal gas pipes with valves kept well away from the path of hot gases; it is necesarry that you choose one of these methods to protect your valves.

Share this post


Link to post
Share on other sites

WRT the first forge: Now say you want to restart one of those burners soon after it was stopped: so you reach over and grab one of the valves and find out that the handle is 400 degF (probably not too much more as it looks to be an alloy that will melt at a low  temp...).  No more forging for you for a while and a visit to the A&E or ER!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now