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

KenH

Well-Known Member
Perhaps while waiting you could stick those concentric rings in the end of burner tube as Ed said he put in his burner. I'll bet it would help the burner with that "big honking" {g} blower you've got.

All in all it does seem like you've got it working pretty good now. Maybe move PSIG up to 8 or 9, then reduce propane flow by closing needle valve more? Just tossing ideas around.
 

jaxxas

Well-Known Member
Yeah I think I'm kinda regretting that 'big honking blower' right about now! :rolleyes:

I was looking at that concentric ring drawing and seeing if I had the parts on hand. So far I can't find any 1" pipe but that doesn't mean I don't have any. I guess with my blower tube being 1.5" I'd just go with 1" then 1/2" and then a 3/8" or 1/4" rod. Hopefully with the blower speed control I won't need it. Before with the damper wide open I learned to open the shop doors before I fire up the forge, if I fired up the forge before I open the shop doors instant headache, O2 deprivation I'm guessing. That big honking blower really sucks the air out of a 400 sq ft shop. With the damper closed (I still open the shop doors) I don't even get a whiff of it.

Yes the forge is heating up nicely and I think it sounds pretty good but it seems to be using a lot of propane. Hopefully blower control will help.

I kinda did a scale for my needle valve. 1.5 turns total, and I was probably doing a whole turn with I lit the forge and the little I backed it off was like a quarter turn, so in the end it was 3/4 open. At least by the knob's rotation, no idea on the total orifice opening.

BTW I checked out those cam hammers they are pretty cool compared to the one I linked to. Maybe you should go for it!
 

KenH

Well-Known Member
Only 1-1/2 turn from full open to full closed on your needle valve? I just checked and one of my needle valves is 5-1/2 turns full open to full close, but the other is only 3 turns open to closed.

There is a possible problem with turning blower too slow, the gas/air mixture might not have required velocity as it enters the forge for good burning. Slower air velocity also will negatively affect mixing in pipe. The big advantage of those concentric rings is providing turbulence to improve mixing and reducing volume of air while at same time increasing air velocity as mixture goes into forge. The more I think of the dynamics of the rings the more important they seem with a large burner pipe. For some reason I was thinking you had a 2" pipe from 90 elbow to forge. Now I see you've got 3" pipe with a 3"X1-1/2" reducing coupling.

I agree with you on size of blower. I really think I could get by with a smaller blower than the 2-1/2" blower (125 CFM) I've got since it never runs at full bore, other than perhaps initial heat up. I'll bet the little 2" blower listed on your link would be plenty, but it costs more than the 125 cfm blower I got off Amazon.

It seems like you're getting details worked out now so you're seeing a HOT forge {g}. Just the final working at tuning. It took me a while to get my forge where I wanted it. While it was working from start, it seemed like there were things I could do to improve.
 

jaxxas

Well-Known Member
Only 1-1/2 turn from full open to full closed on your needle valve? I just checked and one of my needle valves is 5-1/2 turns full open to full close, but the other is only 3 turns open to closed.
There was a complaint on Amazon about the flow rate!?

There is a possible problem with turning blower too slow, the gas/air mixture might not have required velocity as it enters the forge for good burning. Slower air velocity also will negatively affect mixing in pipe. The big advantage of those concentric rings is providing turbulence to improve mixing and reducing volume of air while at same time increasing air velocity as mixture goes into forge. The more I think of the dynamics of the rings the more important they seem with a large burner pipe. For some reason I was thinking you had a 2" pipe from 90 elbow to forge. Now I see you've got 3" pipe with a 3"X1-1/2" reducing coupling.
Not sure I understand that, I understand that they could reduce velocity but volume seems pretty fixed no? Or I guess it is with less velocity you get less volume?

I agree with you on size of blower. I really think I could get by with a smaller blower than the 2-1/2" blower (125 CFM) I've got since it never runs at full bore, other than perhaps initial heat up. I'll bet the little 2" blower listed on your link would be plenty, but it costs more than the 125 cfm blower I got off Amazon.
If I had another 3" nipple I was thinking about making a flange and try the little 54 CFM Dayton. Probably way to small though!

It seems like you're getting details worked out now so you're seeing a HOT forge {g}. Just the final working at tuning. It took me a while to get my forge where I wanted it. While it was working from start, it seemed like there were things I could do to improve.
Yeah I agree, I'm getting pretty close. I hope I can get it fine tuned enough so it is sipping propane like yours!
 

KenH

Well-Known Member
Low flow rate complaint? That confirms the issue you are having.

You might be surprised how well that small blower would work, if you had a 3/4" burner pipe.

The concentric rings provide an obstruction to reduce volume of flow, but with the reduced volume having to go thru a much smaller opening (1.5" is obstructed/reduced with the rings), the same amount of volume has to be forced thru the smaller opening which increases flow velocity.

While the volume of air coming from blower is fixed with respect to no restriction, when the restriction (rings) are inserted the volume of air flow will be reduced. If that amount of volume from restriction, is forced thru a smaller restriction (with rings in) the velocity increases. Much like putting your finger over the opening of a garden hose. With full opening the water flows but doesn't spray very far. Putting your finger over the hose opening you're restricting the size of opening and the spray goes much further due to increased velocity of flow, but the volume stays close to the same. Did that help?
 

jaxxas

Well-Known Member
Low flow rate complaint? That confirms the issue you are having.
Just one guy....


You might be surprised how well that small blower would work, if you had a 3/4" burner pipe.
As my Daddy used to say many many moons ago, IF a bullfrog had wings he wouldn't bump his butt! But I'd bet you are right.


The concentric rings provide an obstruction to reduce volume of flow, but with the reduced volume having to go thru a much smaller opening (1.5" is obstructed/reduced with the rings), the same amount of volume has to be forced thru the smaller opening which increases flow velocity.

While the volume of air coming from blower is fixed with respect to no restriction, when the restriction (rings) are inserted the volume of air flow will be reduced. If that amount of volume from restriction, is forced thru a smaller restriction (with rings in) the velocity increases. Much like putting your finger over the opening of a garden hose. With full opening the water flows but doesn't spray very far. Putting your finger over the hose opening you're restricting the size of opening and the spray goes much further due to increased velocity of flow, but the volume stays close to the same. Did that help?
Yes indeed, very clear, thank you!
 

jaxxas

Well-Known Member
Didn't do much on the forge today. I installed the rear plug and fired the forge up twice to about 1000 F just to cure the plug refractory. Kinda nice not have any back blast out the rear! Probably reduces the forge volume by about 72 ci.....



But I did finally get my treadle hammer bolted down. Kinda amazing that something that weighs in excess of 500 lbs dances all around while you use it...




Obligatory soda can smash...
 

KenH

Well-Known Member
That plug really seals up the rear of forge for sure. Does there needs to be a small opening at rear to help with forge burn. Hopefully Ed or somebody else will chime in on this. For sure the forge will heat up faster and hotter. I think it will work just like it is. My forge is closed with firebrick stacked at rear, but there's always "breathing" area around firebrick.

I LIKE that treadle hammer you've got. It sure flatten the pepsi can.
 

Doug Lester

Well-Known Member
I think that your forge would breath better if you had a port in the back. Also you will be able to work with longer blades in both forging and heat treating. You could always rig a way to hold fire bricks over the rear port if you wanted to close it off.

Doug
 

KenH

Well-Known Member
Doug, I know you've got lots of experience with forging and forges. If you notice is rear cover is removable when the need for long work comes up. Will it work just fine when it doesn't need open for long pieces? If it would work better with a small opening, what size opening would be good in rear for normal work? Seems like I read somewhere a while back it would be good to have a couple sq inches of opening for breathing during normal operation, something like two firebrick with 1/8"-1/4" or so space between them?

I don't have the experience myself to answer that question and would like to know for myself.
 

jaxxas

Well-Known Member
Thanks guys! Right now it seems as if my problem is too much air, not the lack of, if I need to change the plug in the future I will.

Well the only thing forge related I did today was to fire it up to about 2200 F to cure the refractory on the plug, tomorrow I will do the ITC-100 coating on it. It actually seems to take longer to come up to temp than I thought it would, probably the fact of added refractory?

Just a few moments ago I did get my parts for moving the propane tanks. Hopefully that is something I can tackle tomorrow or Sunday at the latest. I had also ordered a new needle valve. My current needle valve has a total of about 1.5 turns, the one I received tonight has 'about' 9 total turns. You can see it's specs here.... Hopefully with a better flow rate and more adjust-ability.

While waiting for the propane 'move' parts I had decided to put the casters on my sandblaster as part of the whole shop reorganization I've been working on for about forever it seems. Something I've been meaning to do, just a question of priorities. It was kinda a pain in the posterior, the sandblaster is not easily disassembled or flipped over, I had to suspend it from the ceiling to modify the legs and add the casters. Took longer than I had hoped, but the casters are on. I still need to add some cross pieces for stability and to support a bottom shelf.



Seems everything takes way longer than you would think!
 

KenH

Well-Known Member
That fuel adjust valve you linked to looks really good. With 4.4 Cv it should flow plenty of gas. You're going to be forging before you know it.
 

jaxxas

Well-Known Member
Didn't do anything with the forge today except contemplate tomorrow!



I'm hoping I have enough of the right steel to build a new shelf for the new gas line to go under. May have to improvise being locked down. We'll see.. I'll may add yet another shelf under that one in the future if needed.


Finished up the sandblast caster mods (shelf). I cut it too long twice! It rolls around easily and without the flexing in the legs that it moved with before, I was always worried it would collapse. And with the 4 casters it's easy to position. Not a lot but one more thing to tick off the list.

 

KenH

Well-Known Member
That needle valve and piping looks like it'll work just fine. Is the valve 3/4" or 1/2"?

Is that the speed controller I see in photo with needle valve? Have you tried it on blower yet?
 

jaxxas

Well-Known Member
The valve is 3/8" in and out.

No I haven't tried it yet. It is a ceiling fan speed controller and rated for 8 amps, my blower is almost 4 amps!
 

jaxxas

Well-Known Member
Well back to the forge today! Didn't seem to get a whole lot accomplished but I tinkered with it quite a bit. First I removed the propane tanks and the gas apparatus and the old blower control. Not sure what the issue was with the old blower control, it did work when I first tested it, though the blower sounded sick, I think it was trying to tell me something! Then I started wiring up the new blower control. And I didn't have the correct 2x4 electrical box to put it in so I just used a junction box and had to build a cover for it. I would have just drove over to ACE and saved a lot of time but you know how that goes these days. Then I made a mount for it so it would be recessed back from the front of the cart. I think possibly in the future I might turn it 90 degrees to the left and route the wires straight down out of the box just for more protection. Anyway I got it all wired up and it works likes a champ, great control. Too bad I had already torn the gas apart as I really wanted to test it then and there! Whenever my new TC gets here I'll probably recess the temp display as well.

You can see the control (looks like it belongs in the living room or something!)....



After which I barely started on the new improved gas system (you can see the new needle valve installed in the picture above). I needed to get that cross-pipe in place to get an idea of where I'm going to place the shelf I plan to build tomorrow. I had to torque on that 3" nipple to get that cross-pipe some what level Cheater bar torque! I only have a single pipe wrench big enough for 3" pipe and a rather large pair of water pump pliers.

Then I applied the ITC-100 to the rear forge plug, as I forgot yesterday. So I have like a half can of ITC-100 left over. I assume proper storage is critical for longevity. I vacuum sealed it twice for now, anybody have any better ideas?

If all goes well tomorrow I'll get the shelf all built out and at least start on the new gas system! Hopefully I have enough scrap plywood for that shelf?
 
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KenH

Well-Known Member
OK, you ran the blower and it works great with the new speed controller - good deal. How slow will the blower run?

Git some gas thar and lite it off!!! {grinning} Won't be long now.
 

jaxxas

Well-Known Member
I looked at that and tried to quantify it but I'm not sure how. Much slower! The difference in air flow was huge and I didn't even have the damper closed!

Yes, yes gas is coming as fast as I can! ;)
 

jaxxas

Well-Known Member
Well first the bad news, no gas today! The good news is that I think I can get the gas up and ready to test in a minimal amount of time in the morning. I don't have to fiddle with all the finicky mounting bits with the gas in the new location just to test it. I only have a few actual gas fitting connections to make, to get the gas running. So hopefully I can test the new setup tomorrow.

So what I did get done today in spite of all the interruptions was building and installing the new shelf that goes above the gas line. There was just no way I could install the gas line first and then install the shelf without removing the gas line. And frankly I'm pretty tired of messing with gas fittings!

Here you can see the gas line and the shelf, me deciding on the shelf's permanent location....




Here is the finished shelf in place. I incorporated the tong(s) rack using the same bolts as the shelf on the front side.




Here's a shot of the gas line clearance (nearly none) under the shelf....

 
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