Forge Assembly WIP

[silver_pilate]

I decided I'd do a forge assembly WIP. I say "assembly" because I didn't build the forge. Rather, I bought it from Darren Ellis. It's a well built tank and will probably last a while longer while looking a lot better than anything I could have put together. This thread will follow as I line the forge, and give some pics fo the PID controller and dual stage setup I'll be using based off of Stacy Apelts designs and JT's schematics.

The forge is 8" in diameter unlined and roughly 13" deep. Here's a few pictures of the forge:





Notice the tube in the above photo on the left side of the forge. It's for a TC, and the ceramic sheath for a K-type TC fits in it just perfectly!

Here's the burner that Darren also put together along with the blower I'll be using:





--nathan

[silver_pilate]

I spent the last two evenings putting together the PID controller box for the forge. Master switch is on the side of the box closest to the forge. As I mentioned before, the burner will be a two-stage setup with PID controller allowing temperature control without losing ignition. It's Stacy Apelt's design, and the low burn will sustain ignition and hold to a low set-point, and the high stage kicks in to bring the forge back up to a high set-point temp after falling too far. Just to make this thread a one-stop-shop, here are the links with discussions and WIP's of JT's forge.

http://www.bladeforums.com/forums/sh...d.php?t=523845

http://www.bladeforums.com/forums/sh...d.php?t=600318

http://www.bladeforums.com/forums/sh...d.php?t=612497

I used the schematic JT put together from Stacy's original sketch as a basis for my wiring. Being a visual person, I had to go ahead and draw it out myself using colors that corresponded with the actual colors of the power cords I was using . Here's what I came up with:





As Stacy reminded me, I did add a 2Amp fuse just after the main switch as well as a 1Amp fuse just before the PID.

Here's the parts I started with:



And following the above schematics, I came up with this:





Notice the cords are all protected that run around the forge just in case. I'll also add some sort of sheild for the SSR (on the outside of the controller mounted to the metal plate to act as a heat sink). I tested it out, and it works...with some quirks. Turns out I wired up the speed controller backwards (no labels on the controllers as to the in vs. out). So when I first tried it out, the blower was blowing full blast at the lowest speed setting. In fact, no matter what direction I turned the knob, the fan trucked along just fine. Turns out there is also a min-speed pot on the controller that I had to adjust to set the min speed. Now, with the knob turned all the way to the right, the fan is running nice and slow, and with the controller turned all the way to the left, it runs full tilt. Note the high and low controllers so that the forge atmosphere can be controlled in both high and low settings.

There will be more to come as far as the gas side of things when I get to setting up the two-stage gas controls. It's basically a needle valves to control atmosphere for each stage along with a solenoid on one stage that opens with currnet from the controller to turn on the high stage.

--nathan

[silver_pilate]

Here's a few pics of the beginning of the lining process.

I started by cutting out the kaowool I'll need for the forge body and end caps. In the second pic I'm actually using the first knife I ever made. It's an hand old saw blade I cut up and put a handle on. It's really thin and cuts the kawool really well:





Here's the kaowool in the end cap and then after the body wool has been installed. I had to mark and cut out for the burner inlet and then punch a hole for the TC as well.







The next thing I have to do is lay down the satanite layer and cure it. I'll have to do some work on the gas side of things first as I need to fire the forge to dry out the satanite fully. I'll post more as I can.

--nathan

[Sam Salvati]

Awesome Nathan, thanks for sharing.

[Rusty McDonald]

Nice build! I like the stand in front of the forge and the fact that you can open it easily to get in side.

[muleskinner222]

Great write up, I'm going to build one of these this spring. Keep the pictures coming.

[amcardon]

Very nice! I'm really glad you decided to do a WIP on this, I love watching these projects!

[bladsmth]

Excellent presentation....makes me want to build a forge.

Another good tip is to use a 1/4" metal gas line from the solenoid to the needle valve. As you have correctly deduced, red hot things have a habit of bumping into wires and hoses.
Stacy

[indian george]

The speed controllers I have the same ones . I notice it has a rather long delay time to turn it up or down. Have you noticed that with yours??? Also where did you get the box for the PID??

[Rusty McDonald]

The speed controllers I have the same ones . I notice it has a rather long delay time to turn it up or down. Have you noticed that with yours??? Also where did you get the box for the PID??

Kinda looks like a project box from Radio Shack.

[indian george]

Kinda looks like a project box from Radio Shack.

Thanks Bro

[silver_pilate]

Yep...project box from Radio Hack. I've used them a number of times for various projects (PID box for my HT oven, speed control for my grinder, etc).

IG, it's hard to tell at this point. It's not instant, but not too slow either. Once it's fully installed and there is a little back pressure, it might be quicker. But with blown burners, as far as I can tell, there isn't much back pressure normally so the blower wants to turn fast. Maybe if you put a gate in front of the blower, you can artifically add in just a bit of back pressure to make the blower more responsive to the controller input. Kind of like your car coasting down hill when you let off the gas pedal vs. going up hill and letting off the gas pedal.

--nathan

[indian george]

Thats how my burner is setup. I feel I got more control with the gate valve than with the speed control. I have my welding forge setup with a PID and I can dial it in to run at 1500 deg. The burner is setup with another gas feed with a needle valve running under 1 psi. So when the control valve shuts off the main feed , it will still ignite when the valve turn the gas back on.

[Josh Dabney]

Nathan,

Thanks for the WIP. I too am planning a similar forge build. It's been on the back burner, so to speak, since getting an Evenheat but I'm hoping to resume my forge parts gathering asap

My goal for 2010 is to attend the Intro class in Texarkana and be fully set up with forge, anvil, hammers, tongs, steel, etc. etc. etc.

Although I have pretty much collected all the info and recieved some advice from Stacy it will be a big help having this WIP with all the info as a guide when it comes time to do my own build.

Just want to tell You, JT, and Stacy that we're out here benefiting from all the info you've put out here and do appreciate it !

Thanks again, Josh

[silver_pilate]

Tonight I built the gas side of the forge. I haven't been able to fire up the burner for a test run just yet as I'm having some technical issues with the controller set up.

Here's some misc. parts I assembled to put the 2-stage gas feed together +/- a few parts:



Use teflon for the pipe fittings. Three wraps should do you good for this size pipe thread. Here's what I put together as it was almost done. One side is the low-stage feed and the other with the solenoid is the high stage. Both have needle valves for atmosphere control.



Obviously, there's a missing part, so I used flare fittings and 1/4" copper line. First I cut the appropriate length of pipe:





Next I flared the ends (be sure to put the flare nuts on the pipe before flaring both sides!!):









Then assembled it. The copper tubing gives you just enough adjustability/flex to get things together and lined up:



And here is the completed assembly:



--nathan

[silver_pilate]

And here's the 2-stage gas feed installed on the burner and connected to the gas line. There is an extra needle valve at the burner just before the ball valve that was already permanently assembled to the burner. I'll just leave it open and adjust behind it:









Once I get the bugs worked out of the PID control system, I'll give it a test fire outside of the forge.

--nathan

[gusval]

Thank You for Sharing

[deker]

Your shop is too clean...dirty it up a bit and start acting like a real bladesmith

Cool project, I'm interested to see how it turns out.

-d

[silver_pilate]

Hehe...it's dirtier than it looks, but I vacuumed recently .

I did some reworking of the controller tonight in order to help resolve a interferrence problem from the blower controllers to the gas solenoid. I replaced the controllers with better units and that helped some, and using Stacy's advice, I set the controllers closer to the same setting to avoid the issue. Turns out if you have both controllers on and at drastically different settings, they start to have problems.

Anyway, after that was done and buttoned up (white knobs now instead of black knobs), I hooked a pressure guage into my regulator and hooked the gas up to the burner to test it out. All seems good, and I'm eager to tune it once it gets in the forge.

The following link is a video I took of the burner running on low/high settings in the open just for testing the system. The problem with running burners in the open is that if you have the mixture right, they tend to blow themselves out. Within the forge, the swirling flame and the heated forge lining will maintain ignition. So in the video, you'll notice the flame is really yellow/rich. I make a few adjustments to get the low burn better, but I'll have to wait until the lining is done before I really see how it does. The following video is running at about 4 psi through the regulator.

http://www.youtube.com/watch?v=g5u0as_Oqlc

I'll tell you, with a blue norther blowing in hard and the temp dropping about 30-40 degrees within 2 hours, that burner really warmed up the shop! And I have a BIG shop (slash storage...20x40 with 15 foot ceilings). I brought the forge body home with me tonight, and I'll probably do the first coat of satanite in the garage tomorrow and let it set up in the house (if my wife lets me). It's better to be above 60 degrees for the satanite to set up and dry, and it's not suppose to get above 30 for the next 2 days with lows approaching zero and windchills well below zero.

--nathan

[silver_pilate]

Ok, I've started lining the forge.

First, I mixed up some satanite. For the first coat, it took me several batches in this size bowel to get it done. Mix it with water, adding water and mixing gradually until you get a consistency like sour cream.





Next you want to dampen the kaowool slightly to help the satanite stick a bit better.



And then, starting at the back of the forge, begin laying down your first coat of satanite. Be careful, as it's easy to begin to tear the kaowool apart if you're not careful. I found I had trouble getting in the very corners of the back of the forge where the body and cap meet, so I dipped my finger in the satanite and smeared it on. Laying down this coat too thick can cause problems with the top of your forge as the kaowool might pull apart from the weight of the satanite until it has dried and has some structural integrity.



Notice I still have the ceramic tube for the TC in the forge and I painted the satanite around it, pulling it out in the end and wiping it clean with a damp rag just to make sure I maintain the opening size I need.

I brought the forge inside (it was about 9 degrees that night), and set it on the dining room table to dry (thanks, babe). I found that after eight hours, the door coat was dry but the body coat was still wet. I placed a fan in front of the forge and directed air through the forge body to speed the drying process a bit. It worked well, and my refractory was nice and dry tonight for the second coat.

Here's the forge body after most of the second coat of satanite:



I'm letting this dry up, and I'll likely fire the forge tomorrow to help cure the satanite before laying down the mizzou floor and filling any cracks that develop. At that time, I will install the ceramic sheath for the TC and seal it with satanite as well. Stay tuned!

--nathan