My forge build.....WIP......it's going to take a while!

Well, "IF" you have he solenoid closed and only the two tanks valved into the manifold, BOTH tanks valves CLOSED, and when you crank the regulator up for output, the it's pretty simple. One of the tank valves isn't closed, or is leaking.
 
Yeah, unfortunately that's what I'm thinking. I'll get a soap spray bottle tomorrow and figure out which one is leaking. Then I'll talk to Amazon or the manufacturer 'FlameKing'! But I don't want to throw away near 40 pounds of propane.
 
Ok..... I gotta jump in here..... I tried to copy the pic to this location.....but it says the file is too large. Anyway....
First off today I cut the radius's on the front of the forge for the firebrick door...

firebricks.jpg



And as I found out this morning the other propane hose I had ordered wouldn't be delivered until Apr 1 or maybe Apr 8, I canceled that order and went ahead and hooked up the SS gas line the hard way. Could have been worse, hopefully I won't be taking it off for a long time....

gass.jpg



Then I built the rack for my tongs....

tongss.jpg



Tomorrow I hope to build a similar looking rack for my hardy tools (with no wood) though I'm not really sure yet where it's going to be mounted.

Also my rear forge plug kao wool is pretty dry from rigidizing so I will do the refractory on it. Still noodling on how to mount it.

I found a 20% off coupon online good through this weekend for Harbor Freight and I need to buy their 2 ton shop crane/hoist/cherry picker. I'm going to need it to lift my treadle hammer so I can bolt it down. Time to brave the corona virus again!

I think I figured out what I'm going to do with my TC stick out issue. I ordered one like Kenh's, I'll have to shorten the TC tube but that shouldn't be a big deal.

OK.... I'm not here to rain on the parade...... BUT......When I saw this pic, the red lights went off, and the red flag went up!! IS THE FORGE SITTING ON TOP OF THIS CART?? If so, this is A VERY BAD SITUATION.

When you're forging, there is gona be all kinds of hot scale, slag, etc falling (I can already see a little bit of stuff on the plywood), and every now and then you WILL drop a hot work piece. I read one of your posts where the heat was melting your grinder guard...... Image what's gona happen with all that electrical and especially the propane hose where it is.....

THIS IS A DISASTER WAITING TO HAPPEN. You REALLY NEED TO RELOCATE ANY OF THOSE ITEMS/PARTS THAT WILL MELT OR ARE FLAMMABLE...... and especially that/those propane tanks.... they need to be AT LEAST 6-8 FEET away from the forge. You're going to do whatever you want, but as it is, this is a very DANGEROUS situation...... I've seen it before, and seen the aftermath of a shop burnt to the ground because of it.

I'm not picking on ya, but folks who don't have experience with forges simply don't realize/understand the things that can go horribly wrong..... if I didn't give a rip....I wouldn't say anything. But I would much rather be talking TO YOU, than ABOUT YOU.
 
Good points one and all, and thank you Ed!

But I would much rather be talking TO YOU, than ABOUT YOU.
This is pure gold!


Believe me I too have concerns about blowing myself up and the hot bits that can fall from forging. And I have dropped hot steel while forging, I know it can and does happen! This forge has been a long time WIP and not all the bits were known in the beginning but there was always a plan that when I finish working on the forge itself to safety up! At least the upper portions of the lower sides will be covered with sheet metal (16 gauge I think) and will have at least 1 hinged steel door for access on one side. I also bought a dual channel thermo couple thermometer to monitor temps both above and below the forge and have 2 alternate plans for the propane tanks if I think the temps under the forge are too high. I've actually already added more heat shield to the top shelf and may replace that board with steel depending on the temps of the next firing.
 
As someone that works in the natural-propane gas industry, I have to agree with Ed. that's a pretty scary looking set up you have there with those tanks right below the forge.
I see a lot of pictures of peoples set ups and am amazed we don't hear of more accidents. personally I hate working on propane systems, it's very unforgiving, and unlike natural gas, when it leaks it settles to the lowest spot on the room and pools up.

As for your tanks leaking, remember when you turn them off, your manifold before the regulator is holding line pressure. you need to open the reg to bleed off all the pressure in the system.
 
If you have room to do it, you could build another cart with wheels to hold the tanks and connect them to the forge with a quick connect hose.
 
As someone that works in the natural-propane gas industry, I have to agree with Ed. that's a pretty scary looking set up you have there with those tanks right below the forge.
I see a lot of pictures of peoples set ups and am amazed we don't hear of more accidents. personally I hate working on propane systems, it's very unforgiving, and unlike natural gas, when it leaks it settles to the lowest spot on the room and pools up.

As for your tanks leaking, remember when you turn them off, your manifold before the regulator is holding line pressure. you need to open the reg to bleed off all the pressure in the system.

I've tried to consider which was more dangerous a totally enclosed unit with no exposed lines or a propane line running across the floor? If my forge was in a fixed location then I could hard pipe the propane line.

On the manifold pressure what I have been doing is turning off the gas at the tanks and letting the forge die before turning off the regulator and the gas solenoid, that should clear any residual pressure I think? Back to the tanks leaking I'm baffled. I tried it with 5 different propane tanks and they all exhibit the same behavior on the gauge and none of them fail a soapy water leak test. And I don't smell propane in any case. Could it be some atmospheric differential in pressure that causes the gauge to move like it does? I'll call the manufacturer Monday and ask them. In the meantime I'm going to swap back to the other gauge and see if it exhibits the same behavior.
 
If you have room to do it, you could build another cart with wheels to hold the tanks and connect them to the forge with a quick connect hose.

This is a great idea and would be easily accomplished with a cheap modified hand truck. Shop space being what it is (or isn't in my case) I'm not sure of the best way. I can clear a space under some shelves about 6' away and then deal with the exposed propane line, or I could conceivably (painful) put them outside by the air conditioner and still deal with an exposed propane line. Of course in any case I'm still dealing with an exposed propane line! I suspect outside the tanks would heat up more from the sun than from under the forge cart. That could be tested. As my forge cart sits (after buttoning it up) I'm only dealing with an exposed electrical cord as I suspect all blown forges do to some extent?
 
I tried it with 5 different propane tanks and they all exhibit the same behavior on the gauge and none of them fail a soapy water leak test.
Your soapy water test is on the tank valve itself, with nothing connected to tank, you've got tank valve closed and there's no bubbles detected with soapy water? I watched the leak video again, why are you turning the regulator down so it shows zero PSIG? I suspect even with your procedure of turning off and bleeding down you've got residual propane in regulator/manifold. Try not turning off the regulator, after all a regulator is NOT a ON/OFF valve. Leave regulator set where it's at. Bet you won't see any pressure build up on gauge then with tanks turned off.

Joe, you've tested temperature of tank area after forge is up to temperature and find the tank area isn't all that hot. BUT, after the forge has been running for an hour or two a LOT more heat is going to build up in tank area. My feeling is anytime a propane tank gets hot enough I can't comfortably hold my hand on it, it's too hot. I REALLY like the idea of using a cheap hand truck, and remember the propane hose that's laying across the floor is well away from any hot slag or metal that might be falling. It doesn't take but just a moment to connect that swivel to the forge, or even a quick connect fitting is used by many folks.Something like this: https://www.amazon.com/dp/B072JCWJ9D/
 
Your soapy water test is on the tank valve itself, with nothing connected to tank, you've got tank valve closed and there's no bubbles detected with soapy water? I watched the leak video again, why are you turning the regulator down so it shows zero PSIG? I suspect even with your procedure of turning off and bleeding down you've got residual propane in regulator/manifold. Try not turning off the regulator, after all a regulator is NOT a ON/OFF valve. Leave regulator set where it's at. Bet you won't see any pressure build up on gauge then with tanks turned off.

Joe, you've tested temperature of tank area after forge is up to temperature and find the tank area isn't all that hot. BUT, after the forge has been running for an hour or two a LOT more heat is going to build up in tank area. My feeling is anytime a propane tank gets hot enough I can't comfortably hold my hand on it, it's too hot. I REALLY like the idea of using a cheap hand truck, and remember the propane hose that's laying across the floor is well away from any hot slag or metal that might be falling. It doesn't take but just a moment to connect that swivel to the forge, or even a quick connect fitting is used by many folks.Something like this: https://www.amazon.com/dp/B072JCWJ9D/


Yes you are correct! If I don't mess with the regulator the PSIG gauge stays the same. And I guess I'm okay with that, but if I turn off the regulator after the manifold is drained and then back on then I get an increased PSIG level. Don't really understand that.

Yes, I agree on the heat build up! If it get's too hot I will definitely move to another plan. I do plan to test that scenario. What is too hot? 120 F would probably do it for me though I'm sure they get much hotter in the Arizona sun. I like the idea of the propane hand truck too, but space wise I'd probably clear out the underside of a shelf and park the tanks there. I also like the quick connect, in fact I think it would be mandatory in this scenario. But I think the propane hose lying on the floor leading up to the forge is ultimately subject to hot flying metal. Maybe I could slot a large piece of pipe to encase it in?
 
It just clicked for me on the build up of pressure with tank valve off. When you turn tank valve OFF and allow propane to burn down, then solenoid valve clicks closed. Even though all the pressure has been relieved the space inside the hose, regulator, manifold areas are still filled with COLD propane. The propane is cold because it's been going out under pressure, and just how cold it can get is shown by a tank frosting up with heavy use. Then, as the hose assembly sits there the propane warms up to ambient temp, and thus builds that small amount of pressure. I'm not totally sure why it doesn't build pressure if the regulator is left open, or it may if you check it.
 
That sounds a whole lot better than anything I've come up with! I plan to do some more testing on it today. I'm also going to re-evaluate the whole propane tank issue. If you get enough people telling you it's wrong then I need to step back and re-think things.
 
I'm back! If you get enough people telling you are wrong it's time to step back and re-evaluate. So thank you to all commenter's online and off.

KenH has finally beat it through my thick skull (I didn't earn my screen name for nothing!) when he mentioned the possible heat build up under the forge after an extended forge session and while I had tested that on a minimal trial run, no way could I know in advance about heat build up in an extended forging session. And while I considered I could probably mitigate that by adding a fan or more insulation it struck true that by adding the sheet metal shields I had planned I would only exacerbate the problem by reducing air flow. Though there will still be at least 1 sheet metal shield to protect the wiring.

So I've been working on a plan to move the tanks. I'm one of those guys who can't move forward until a plan gels in my head. One of my biggest hang-ups was the propane line on the floor around the forge itself. My forge blower sits on the left side of my forge and my propane supply needs to come from the right side. The longest SS braided line I could find was about 10' for like $85. Doable I suppose. Again KenH to the rescue by suggesting I just hard pipe the line under the forge and then use my existing SS braided line for the connection across the floor to the tanks. Perfect, never occurred to me though. So I went through the whole process of finding the right parts and they should all be here by the end of the week or so. Not like I should be making trips to ACE in today's environment!

Any way, next post up some testing now that I have real control over the PSIG of the propane.
 
Ok there is a lot of info attached, I'm sure a lot of you don't care to see it but let me sum it up by first saying that I had had my PSIG gauge in the wrong place previously. Now I have moved it to the correct place, upstream of the needle valve, and now I can actually know how much gas I'm putting out with the regulator. Not sure what happened previously to my gas system when it seemed ready to melt down my shop.

The upshot of today's testing is that if I close the damper on the blower the temps go up, if I open it the temps go down. If I close down the needle valve the temps go down, so I'm running it pretty much full open. And basically if I run with anything less than about about 7 PSIG my temps go down, At 7 PSIG the temps will keep going up. I'm sure there is a sweet spot in there some where.

Below are some videos I shot of today's test...


I hope I got these in the right order.....

So my conclusion (which is by no means conclusive!) is that I have too much blower. Interestingly enough I tried kicking my blower into variable speed mode at one point and the blower didn't work at all then. Though it has worked before in variable speed mode, so I don't now what happened with that? And I couldn't get the variable mode to work afterwards either. So if anybody knows of a better variable speed controller please let me know.

As always I appreciate any comments, criticisms both negative and positive.

And lastly I have my castable plug going into the oven for drying out today.....

plug.jpg
 
Last edited:
I downloaded all those videos and watched them. From what I'm seeing you've got the speed control set as high as it will go, just before it clicks OFF?. With the pressure set at 4 psig, needle valve wide open, and the blower damper fully open it burns nicely, then closing the damper the temperature increases? Good, now close the needle valve some. How much dragon breath (flame) do you have coming out of front of forge?

In video #3 if with pressure at 4psig it sounds like the forge is burning evenly, no sputtering? What if you open the blower damper a bit, does it still sound good? what happens to temp? Are you saying it will drop even more?

Too much propane is a rich mixture and usually will result in flame from from forge - and MUCH easier seen in heavy shade or at night. Can be very hard to see in bright sunlight.

Another variable is the needle valve, just how much does it flow when wide open? My needle valve might be flowing as much 1/2 open as your valve is fully open thus could need different pressures. You needle valve is located right on the blower pipe screwed into the 1/4" nipple into pipe? I think I'd rather see higher PSIG and the needle valve closed some to provide more of an orifice effect causing the propane to go into the air stream at higher velocity to improve mixing some.

It could well be your needle valve is sized such it needs 7psig (or more) to pass enough propane for full burning heat. If so, it means your needle valve is more of an orifice than a valve.

Sent you an email
 
I downloaded all those videos and watched them. From what I'm seeing you've got the speed control set as high as it will go, just before it clicks OFF?.

For whatever reason speed control isn't working at all no more, if I try to use variable speed the blower shuts down! The blower is running at top speed with the damper fully closed.

With the pressure set at 4 psig, needle valve wide open, and the blower damper fully open it burns nicely, then closing the damper the temperature increases? Good, now close the needle valve some. How much dragon breath (flame) do you have coming out of front of forge?

So again the damper is already fully closed, if I close the needle valve the temp goes down. I have very little to no dragon breath.



In video #3 if with pressure at 4psig it sounds like the forge is burning evenly, no sputtering? What if you open the blower damper a bit, does it still sound good? what happens to temp? Are you saying it will drop even more?

Yes the temp drops.


Too much propane is a rich mixture and usually will result in flame from from forge - and MUCH easier seen in heavy shade or at night. Can be very hard to see in bright sunlight.

It's fairly bright in my shop and I don't see much if any dragon's breath.

Another variable is the needle valve, just how much does it flow when wide open? My needle valve might be flowing as much 1/2 open as your valve is fully open thus could need different pressures. You needle valve is located right on the blower pipe screwed into the 1/4" nipple into pipe?

Agreed, I have no way f knowing how much the needle valve flows when wide open. Correct on the needle valve location, right after the blower and right before the elbow, on a 1/4" nipple.


I think I'd rather see higher PSIG and the needle valve closed some to provide more of an orifice effect causing the propane to go into the air stream at higher velocity to improve mixing some.

Sent you an email

I can try that!
 
For whatever reason speed control isn't working at all no more, if I try to use variable speed the blower shuts down! The blower is running at top speed with the damper fully closed.
I wasn't sure, it sorta looked like the blower was still plugged into the speed controller, but of course I can't see to tell. The blower is plugged direct into an electrical outlet. Good deal. Looking forward to report on how it works with higher pressure.

I expected you'd already covered the other points I raised, but didn't want to "ass-u-me" anything.

Hang in there my Friend - it's going to work out.
 
I wasn't sure, it sorta looked like the blower was still plugged into the speed controller, but of course I can't see to tell. The blower is plugged direct into an electrical outlet. Good deal. Looking forward to report on how it works with higher pressure.

I expected you'd already covered the other points I raised, but didn't want to "ass-u-me" anything.

Hang in there my Friend - it's going to work out.

Yes it is still plugged into the speed controller, but the variable side of the speed controller isn't working at all but the normal 'ON' side still works fine. The variable control seemed to work just fine when I first hooked it up but no more for whatever reason. I ordered a new speed controller from McMaster Carr.

I'll give the higher pressure test a trial run in the morning.

FYI, I haven't had a chance to check my email yet!
 
Shucks, I just noticed the VAR-OFF-FULL selector switch at the right side. Your speed controller looks just like the one I have, EXCEPT, mine doesn't have the selector switch your's has. Now I understand the "FULL ON" for fan speed statement.

Looking forward to tomorrow's report.
 
Tested the forge again, I first cranked the gas to 9 PSIG, blower damper shut, and just opened the needle valve until the forge lit. Unfortunately I don't know how much I opened the needle valve, maybe half. (I'm going to make a scale for it today!)

The forge got up to about 1800 F pretty fast (maybe 15 minutes) but the temp gain had started to stall quite a bit. The gas PSIG had dropped to about 6 PSIG, so I cranked the gas back to about 7 PSIG and the forge got up to about 2150 F fairly quick. Then I started messing with the settings. If I open the blower damper at all the temps go down. If I reduce the gas PSIG the temps go down pretty quick. I was able to back off (close) the needle valve a bit before the temps started dropping.

I still think I have too much blower. My new variable control won't be here until Friday. So today was probably my last test in this configuration as I prepare to move the tanks.

Here is a link to the blower page where I bought my blower. I bought the 3" and I probably should have bought the 2.5"!

 
Back
Top