Furnace build thread

[Lawrence Duckworth]

I was thinking I'd figr that out after i see just how nasty this stiff is. I have a 1000 ellbeez of batch here and it kinda looks bout like trinity white cement.

[Pete VanderLaan]

When you buy batch from Spruce Pine it's always best to get it made when the temperature is pretty cool- 65F or colder. It doesn't pelletize well at all when it's hot out. Above 80F is pretty dicey.

[Rollin Karg]

We recently tore down an Old Moly and got a surprise. It had been getting a little sluggish, so we expected a Jellyroll. There was about a two inch thick Jellyroll but above that there was cavity of about eight or nine inches high and maybe four to six inches wide. There was still some Frax left against the metal and it was still making glass, but it was way under performing. At first it was a puzzle. After some I believe the moisture in the batch was causing enough pressure to force air and batch out through any opening, including the crack at the bottom. This mixture ate up the Frax.

Our furnace wall is 3.5“ thick and the bottom 17” is Mizzou. The rest is Kast-O-lite 30.The Mizzou is stout but after enough cycles it will crack. This furnace is over six years old and melted twice a week for a lot of that time. If you don’t keep the bottom clean and/or you break a pot the crack is going to allow the glass back where it doesn’t belong. The cavity that’s something new.

Before we saw this, the plan was to make a change in construction. I think it will solve two related problems. Our plan is to add four layers of soft brick(10”) on the outside of the Mizzou part of the furnace liner. I’m hoping this will stop the jellyroll and give some protection against the batch gases.

We have a vent hole in the door to let out some of the gases. We’re going to add another step and start doing as Pete says and leave the door open for 45 seconds after throwing in the batch.

[Pete VanderLaan]

Get the fluorine out of the batch and things will do even better Rollin. I wasn't kidding.

I did put that thermocouple tube in to the door when I cast it and two nights back I did a cad sel melt. Today I looked at the handle on the door above where the tube is. There was about an inch of gassed off material built up on the underside of that handle. Quite a bit for one melt and that's just what stuck. The door port casting has a tiny glaze on it but almost nothing

Simply put, your furnace is under pressure. It will find a way out. If it's a fluoride gas mix, it will dissolve things as it passes through. I would bet it wasn't just moisture from the batch that ate your fiber. The Calcium fluoride had a lot to do with it.

[Rollin Karg]

Originally Posted by Pete VanderLaan

Get the fluorine out of the batch and things will do even better Rollin. I wasn't kidding.

Already done !!

[Pete VanderLaan]

Did you figure out any new element configuration?

[Pete VanderLaan]

Originally Posted by Rollin Karg

We’re going to add another step and start doing as Pete says and leave the door open for 45 seconds after throwing in the batch.

**************
Steve Smyers used to charge charge batches like cad sels and would just shut the furnace off until it glazed over. I think with an electric it would lose a lot of ground doing that but I will throw it out there as an option.

What I notice with those glasses is that the real action doesn't start for about 1.5 hours. At that point it's really smoking. I always throw in all of the batch in one charge. I don't like multiple charges on Cad Sel stuff. I don't like being in the building much either.

[Rollin Karg]

Originally Posted by Pete VanderLaan

Did you figure out any new element configuration?

No, that's a longer term project and I'm still thinking about it. I could go a long time like I'm set up now.

[Lawrence Duckworth]

update

Here’s what the shop looks like from the workbench.

finished up on the annealers and furnace wiring yesterday and everything seems to work okay. the furnace transformer makes a pretty loud buzz that concerns me though…about as loud as what I imagine a 2-lb. bumble bee might make. I’m wondering if the noise will settle down once things get up to temperature???

i will be melting SP Batch

[Lawrence Duckworth]

the bench

[Steve Stadelman]

The transformer is really being slapped around at low draws during low temp ops. The scr is just chopping the hell out of the sine wave and that is what makes the transformer buzz. It will settle down when it gets hot and uses more power.

[Pete VanderLaan]

Hey Lawrence, That's an art piece in itself. I would not want to be the first person to drop hot glass on the floor or the dog. I have you beat only on the bench. Mine is a solid piece of 2 inch thick Oak 30 inches wide that we milled down in the woodlot field. Mary Beth made it into a bench for me.

I don't see your transformer. Put a small blower on it to keep it cool. It will make a big difference down the road.

It's just beautiful. Make good things.

[Drew Jaeger]

The studio is looking very nice. I'd be afraid to use it for fear of scratching something.

[Lawrence Duckworth]

Thanks Steve. I've been searching for a moly startup cheat sheet, I think John Riepma wrote
a cold start schedule some time ago. (A smart man might cut/paste tidbits like that to a glass notes folder)

Pete...The bench sounds purdy cool!

[Scott Novota]

As always, that is just so pretty.

Thanks for the start to finish pictures. It was been very interesting to watch and secretly turn green.

[John Riepma]

Or he might post to his thread and prompt me to repeat myself...room temp to 1000F @ 36 degrees/hr., hold at 1000F for 24 hrs. Raise to 1100F at 18 degrees/hr, hold at 1100 for 6 hours. Raise to 2050F (or whatever) at 36 degrees/hr.

I'm sure other schedules work, some better, some not so much. We've done this a number of times and never cracked a pot. The cost of the pot and the contribution to Pete's yacht payments doesn't bother me, the changeout is enough of a pain in the ass to make me want to avoid the opportunity.

When we're shutting down I just turned it down to 100F and watched it carefully, it went through the 1100-1000F range even slower than the 18 degrees/hr we ramped it up at. A week later it's still at 400-500 degrees.

And your shop looks absolutely beautiful. The next time I'm going through your area I'd love to stop and see it.

[Lawrence Duckworth]

John, I searched and found your post earlier this morning…if I could now just prompt a step-by-step, button-by-button Watlow EZ Zone programing cheat sheet from somebody, that’d be great!
The Watlow EZ Zone is probably a popular enough controller to warrant a place in the sticky archive section with just the necessary program info to start, ramp, batch and temp maintenance. (Pete)

I did figure out how to run the furnace at an unattainable temperature for five minutes and glaze the elements, and I believe I’ve set the temperature limit to a *WAG# of 2380f…but not too sure about all that either, I’ll need to refer to the 164 pg. whatlow manual again. (*WAG=wild ass guess)


You’re welcome anytime John.
I’m glad some of yooz guyz enjoyed the build….art is a process

[Pete VanderLaan]

If you are taling about the watlow 980 series, I can post how to do a programing ramp step by absolute step. If you want to mess with SCR I pretty much get Steve to talk one on one to people.

It really is in the manual and even I could do it, which is saying something.

[David Patchen]

Wow, your shop is beautiful! Looks like a dream shop. If I'm ever out that way I'd love to see it in person as well. Nicely done!

[Allan Gott]

...........forgive me......I just wanna run around on the floor with muddy feet.......oh wait.....your dog probably already did that.......

[Lawrence Duckworth]

For what its worth,
Jason at watlow walked me through what I think would be next to impossible with out his help. After figuring one of the TC wires needed switching he walked me through the ez-zone setup.

Hats off to Watlow and Jason at tech support!

[Lawrence Ruskin]

So write it down and post it.

I had to get an electrician out here and between the two of us we figured it out for the watlow on the stadel-mini.

Now that I have the program in it, it's a piece of cake to start it.

But that was one smart electrician and that f**k, F**k, manual had him puzzled for an hour or two...

[Pete VanderLaan]

I have the 982's. Steve tells me that the EZ series is anything but easy. I think the engineers should have to sit with their mothers at a table and watch them try to program it.

[Lawrence Duckworth]

If you want to make room for this… http://watlow.com/downloads/en/manua...%20D%20PID.pdf or just push the buttons he tells you to.

[Lawrence Duckworth]

Originally Posted by John Riepma

Or he might post to his thread and prompt me to repeat myself...room temp to 1000F @ 36 degrees/hr., hold at 1000F for 24 hrs. Raise to 1100F at 18 degrees/hr, hold at 1100 for 6 hours. Raise to 2050F (or whatever) at 36 degrees/hr.

I'm sure other schedules work, some better, some not so much. We've done this a number of times and never cracked a pot. The cost of the pot and the contribution to Pete's yacht payments doesn't bother me, the changeout is enough of a pain in the ass to make me want to avoid the opportunity.

When we're shutting down I just turned it down to 100F and watched it carefully, it went through the 1100-1000F range even slower than the 18 degrees/hr we ramped it up at. A week later it's still at 400-500 degrees.

And your shop looks absolutely beautiful. The next time I'm going through your area I'd love to stop and see it.

Went good!

The furnace struggled to recover for about an hour and a half after each load yhough (half bag at a time).