Expanded Freon tank forge WIP PIC Medium...Opinions?

[Brian Ayres]

Thought I'd share my freon tank forge build. I've been holding off on making a freon tank forge, I am going to make a PID controlled,dual burner, blown, bigger forge because I want to be able to do larger/longer pieces and heat treat,normalize accurately and wasn't finding any free longer pieces of steel for a venturi forge. But, it'll be a month or two before I tackle the the blown forge, meanwhile, I have hammers, anvils and tongs itching to be used.
I didn't want to have an open back on this forge to accommodate longer pieces...Then I thought about the taper on the tanks and figured I could tack two together!
I bought refractory cement from a local company and their version of ITC/Plistix. I already have the Inswool from the local ceramic/pottery wholesaler.
The gas regulator came from a BBQ/Turkey Fryer place it Texas because at the time Ellis was "lagging" in shipping...(note,I hear nothing but good about Wayne and High Temp ) It's a 50 PSI Propane reg...
I bought the parallel fitting from my plumbing wholesaler for my venturi burner, the rest was scrap, including the 304 SS flare that came from 28' of a sliderail out of a sewage ejection pit :barf:... The choke plate was from the GIB packaging the tension spring is from a Delta faucet seat, the screw from a floordrain cover.

I started with the scrap bin at work...

Donned the appropriate safety gear, respirator, and eyewear..
Then I chose two tanks...
Cut the end off of one, cut another in half with a cut off wheel on my grinder. All holes, cuts, were rounded off to keep me from bleeding throughout the project.

Due to the tapered and, I was able to set one inside the other and tap it together, actually, I did it to test it, and it took me ten minutes to get them apart because I hadn't cut out the back of the blue tank yet.... I don't think welding would be needed...I will weld a base on and add a tong/work support....

I measured in 3" from the back to allow for the insulation and refractory at the back, then centered the hole in the tank for the burner. Drilled it with a hole saw....

Next, I added an 1-1/2"x4" BI nipple. I used the lock nuts off of an 1-1/2" EMT electrical conduit connector to lock the nipple in place. I'll likely eliminate the locknut and weld it in place. I'll tap the nipple with a couple bolts to anchor the burner in place.
I then threaded it onto the handy dandy pipe rack at work and carefully bent the tank to bring the burner in on an angle....I assisted the bend with a hammer to keep it from kinking...

Here is my burner I made. It's based upon a Zoeller Z burner.

Next, I'll weld on a piece of angle for the base, and build a work rest,tong support....I'll finish it this weekend.
Anything I'm missing? I'm going to also add a thermocouple port. So I can properly normalize, and see get my temps for quenching set.
I also have a bunch of soft fire bricks from work, I'm going to weld 2 pieces of angle to the base to make brick doors on the front.. That way I can close the opening off, anneal etc...

 

[jawilder]

Looks good. I would recomend welding the pipe in place rather than using the conduit connectors. I used those on mine and it held for a few months until they got hot and bent under pressure. There is NO way to get in there after the insulation and satanite has been set to replace or tighten it. It is now welded in place

 

[Brian Ayres]

Looks good. I would recomend welding the pipe in place rather than using the conduit connectors. I used those on mine and it held for a few months until they got hot and bent under pressure. There is NO way to get in there after the insulation and satanite has been set to replace or tighten it. It is now welded in place

Yup, will do!

 

[Stacy E. Apelt - Bladesmith]

On the tong/blade rest, here is a great tip.

Weld a pair of 3/4" ID pipes on each side at the height you want the door shelf ( usually the floor height). Make a sliding "table" from two 3/4" steel rods and a 1/4" plate to go across them. Put the rods in the pipes and clamp the plate on. Weld it in place. Now you can slide the work shelf in and out as needed for tongs, blades, or long bar stock. You won't even need to put one on the forge body.

There are many other things that can be thought of for this type of system. I'll give a little food for thought:

When moving the forge about, slip a pair of 48" rods in the slides and two chaps can carry it litter style.

Sliding back plug for welding damascus...no back opening......slide on to plug, slide off to use the through port for swords....Always a perfect seal.

Building a micro switch bar into the work shelf and having it turn the gas from full to low when steel is not in the forge. ( weight pulls bar down and closes the switch....remove the tongs/blade/bar and the switch cuts out the "HI" solenoid) It saves on propane, and this easily works into my two-stage burner control.

Damascus twisting jig - make the pipes to take 1" rods. Have a vise bolted to a plate welded across the rods at back port, and a rest that slides on the front rods, centered at the front opening. Weld a piece of large square stock to both ends of the billet, clamp the square stock in the vise, and use a socket wrench to twist from the front while the billet is in the center of the forge.

 

[artificialj]

Cool ideas Stacy! I might just borrow some for a forge I'm making next week.

 

[Brian Ayres]

Update... Ordered an Auber instruments, PID, Thermocouple, project box, SSR, heat sink, and thermocouple shield and thermocouple disconnects. Picked up several feet of 1" pipe, and some 1/4" plate, angle iron for some legs and 1/2" rod to make the tool rest.
I want to build a blown dual burner, solenoid/PID controlled forge next so I got the heat sink and SSR to wire into the project box now.

Question? Where is the best location in the forge for the thermocouple/shield?

 

[Stacy E. Apelt - Bladesmith]

The simplest way is to add what looks like another burner port and make it so the TC sheath can be slid in and screwed in place with a thumb screw. Just make it where a center burner would be. That places the tip in the center top of the forge.
Pack K-wool around the sheath ,and use some furnace cement to seal it in place. By having all the ports line up, the look is quite professional. You can even use a length of BX cable sheath to run the TC leads from the port tube to the project box. That really makes it all look good and prevents the wires getting damaged.

 

[insanity]

Nice project. Another potential problem with the conduit connectors would be if they are galvanized. Welding is way more fun anyways.

Wayne Suhrbier

 

[Brian Ayres]

A couple of questions before I weld this up this weekend.

First, this is my first forge build beyond my firebricks. I'm 100% booklearned. No actual experience. I'm 39 years old, a service plumber and 32 credits into a mechanical engineering degree, or, metallurgy or whatever I decide to be when I grow up...(actually thinking Art school now )..... that's just a qualifier that I'm fairly bright(don't ask my ex-wife though) and I can reverse engineer almost anything...
So... with my firebrick forge getting the burner in on a tangent helped even out the heat in the chamber.

I posted this build on Iforgeiron in their forge thread and it was said by one person, who I assume has more "real" experience than I do that I'll have hot spots, and inaccurate temperature reads, and hard, if even possible to hit my temps accurately... with a forge like I'm building.
Does my bringing the burner in on a tangent make a difference? like a 6 or a b on it's side....

He also said 2" of refractory was too much and would waste fuel. My thought was the thicker refractory would absorb heat and provide a more stable temperature....More mass....

I have the PID coming today or Saturday with a heat sink, SSR,thermocouple,etc, etc and can start over and make this a blown forge. I can get a blower from work if I want....

All I'm working with now is 1080/1084 so I wasn't too concerned with hitting exact temps for long times yet... I do understand that a venturi burner is far less adjustable than a blown forge...

I can build it, use it strictly for forging, and buy a 120v Evenheat and use that for my soak times, heat treat and just use the forge for forging...

In the end, what I want is to make the best blades possible. My time is limited because of 60-70 hour work weeks, so, I don't want to spend 10 hours on a forge that gets hot on one side and is worthless for anything other than forging...

Thoughts?

 

[thegeek574]

find ron reil's freon tank forge page. it was really helpful in getting mine together.

 

[NickWheeler]

Does my bringing the burner in on a tangent make a difference?

Yes, in my experience it does. When you first fire up a forge with the burner coming in tangentially, you can actually SEE the flame swirling around inside the forge. ALL of my forges have had the burner come in on a tangent to the chamber. I have seen forges in other folks' shops that didn't, and the flame came in on the workpiece like a weed burner, bounced off the work piece, THEN tried to even out inside the burn chamber. If the flame comes in and utilizes the LINER to help distribute the heat, then you're not using your blade like a piece of refractory material.


He also said 2" of refractory was too much and would waste fuel. My thought was the thicker refractory would absorb heat and provide a more stable temperature....More mass....


I don't understand this one. A better insulated forge well retain more heat, rather than let it dissipate out into the shop. I agree completely with you about more stable temps too. I'd like to know the thought process/reasoning behind his/her comment there.


I have the PID coming today or Saturday with a heat sink, SSR,thermocouple,etc, etc and can start over and make this a blown forge. I can get a blower from work if I want....

I personally like blown forges... but there are some guys out there with some crazy amazing venturi forges.


All I'm working with now is 1080/1084 so I wasn't too concerned with hitting exact temps for long times yet... I do understand that a venturi burner is far less adjustable than a blown forge...

Not to sound like your Principal or Mom, but don't cut yourself short before you start. If you can dial the temps in, you'll be much happier with the 1084.


I can build it, use it strictly for forging, and buy a 120v Evenheat and use that for my soak times, heat treat and just use the forge for forging...

A heat-treat kiln is a VERY nice thing to have, but if you're going to spend the $$$ on one, I'd get a 220 unit... MUCH faster response time. It's not just the initial time it takes to heat the kiln up, but how fast it gets back up to temp when you put a big, cold blade in it, or open the door to take one blade out and want it to get back up to temp for the other blades that are still in it.

If you're going to add a PID controller and solenoid, you can dial the forge in to very close temperature ranges. Most of the time I think it's overkill for forging, but for thermal cycling and hardening, it's a great feature.

Looking forward to seeing this thing with fire coming out of it!

 

[NickWheeler]

BTW- Just make the round burner hole an ellipse and you can rotate your burner to come in at a tangent (since you don't have any legs or a base welded on it yet). And remember to make it tangent to the BURN CHAMBER, not the outer shell.

EDIT--- I just realized you said you're lining it with castable. Now I understand the other guys' comment. It takes a cast forge a long time to heat-up...so there goes your fuel costs. I would line it with KaoWool, CeraChem, etc.

 

[insanity]

You said that you had ceramic blanket. Put a layer or two of the blanket against the outer shell. Cover this with a ridged refractory castable or coating. 1" blanket is the most common, 2" will give you very good insulation. The more solid (castable) refractory the longer it will take to come up to temp, but the better it will hold at temp. If you think you will be doing long forging sessions a cast liner can be good since they are way more durable. If you are going to do shorter sessions (1 hour or so) the blanket will be better. Unless you need to outside of the forge to look pretty you can just bend the shell around the inlet pipe to put it at an angle if you have already welded it. If not just oval out the hole.

Wayne Suhrbier

 

[Brian Ayres]

Does my bringing the burner in on a tangent make a difference?

Yes, in my experience it does. When you first fire up a forge with the burner coming in tangentially, you can actually SEE the flame swirling around inside the forge. ALL of my forges have had the burner come in on a tangent to the chamber. I have seen forges in other folks' shops that didn't, and the flame came in on the workpiece like a weed burner, bounced off the work piece, THEN tried to even out inside the burn chamber. If the flame comes in and utilizes the LINER to help distribute the heat, then you're not using your blade like a piece of refractory material.


He also said 2" of refractory was too much and would waste fuel. My thought was the thicker refractory would absorb heat and provide a more stable temperature....More mass....


I don't understand this one. A better insulated forge well retain more heat, rather than let it dissipate out into the shop. I agree completely with you about more stable temps too. I'd like to know the thought process/reasoning behind his/her comment there.

I thought so too... I wasn't going to make it super thick... Just enough to retain heat. the Inswool alone would heat up quicker, but wouldn't retain the heat well after the burner is off? Would less refractory allow faster cycling of temps up and down for normalizing?

I have the PID coming today or Saturday with a heat sink, SSR,thermocouple,etc, etc and can start over and make this a blown forge. I can get a blower from work if I want....

I personally like blown forges... but there are some guys out there with some crazy amazing venturi forges.

I can do it blown if that's better, heck, I could even do a little more cutting and do a ribbon burner.....hmmmmmm

All I'm working with now is 1080/1084 so I wasn't too concerned with hitting exact temps for long times yet... I do understand that a venturi burner is far less adjustable than a blown forge...

Not to sound like your Principal or Mom, but don't cut yourself short before you start. If you can dial the temps in, you'll be much happier with the 1084.
Lol. Alrighty. I'll make sure I dial it in!

I can build it, use it strictly for forging, and buy a 120v Evenheat and use that for my soak times, heat treat and just use the forge for forging...

A heat-treat kiln is a VERY nice thing to have, but if you're going to spend the $$$ on one, I'd get a 220 unit... MUCH faster response time. It's not just the initial time it takes to heat the kiln up, but how fast it gets back up to temp when you put a big, cold blade in it, or open the door to take one blade out and want it to get back up to temp for the other blades that are still in it.

If you're going to add a PID controller and solenoid, you can dial the forge in to very close temperature ranges. Most of the time I think it's overkill for forging, but for thermal cycling and hardening, it's a great feature.

Yeah, the PID was mainly so I can normalize and hit my temps for hardening... It wouldn't be really used for forging.
Looking forward to seeing this thing with fire coming out of it!

I am soooo ready to have this done... I'm picking up my disc grinder today. Have my 2"x72" done,I also have 40' of 1080 and 1084, have 2 anvils, 5 hammers, a couple pairs of tongs, a hundred pounds of handle material, Corby bolts,sand paper, 40 pounds of wrought, 2 drill presses etc. etc....... And I'm DONE... with the tool buying/building for a while. I have 3 unfinished knives and need to heat treat them to finish them....

I was going to do 2" of Inswool. I also have plenty(55#) of castable refractory that I was going to coat the Inswool with. I can make it thinner or thicker depending on what's ideal. I have I also have an IR reflector product that's the equivalent of ITC-100 Plistix, I have 3# of that, almost a gallon premixed...The plan was to do a coating of refractory and then coat that with the IR product.
I bought the IR stuff from a company here that makes heat treat ovens etc for commercial applications...

I bent/hammered("planished") the tank to bring the burner mount tube in on a tangent to what the Inswools inner diameter will be....

To be clear. I am a factory trained WH service/warranty plumber. I work on Boilers up to 2 million BTU's. power burner, tankless, venturi type atmospheric burners, computer controlled etc.I can build anything.:thumbup:


This #@*%$# forge is the final piece of my puzzle to start. After this, I can add a mini-mill, and heat treat oven etc down the road.

I know I'm overthinking it a bit... But I don't want to heat treat myself unless I can do it RIGHT!

I also have 2 pieces of 12"x24" sched 40 pipe from the Union halls welding class... Maybe make a vertical forge???

I have to admit. I do like building the stuff. There's just SOOOO many ways to do it. It's hard to know what's ideal...

 

[A C Richards]

In my experience using a combination of 2" cerachem and a heavy layer , about 3/4-1", of castable works great. I may use a bit more fuel bringing it up to temp but the payoff is in the tight control of the forge and rebuilds. I only have to rebuild every 1-2 years. When I used just the cerachem with a light wash or ITC only I was rebuilding every 2-3 months. Actually my most efficient forge was all castable with no wool at all. But the chamber was too small to do any large Damascus billets.