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Eben Horton
03-11-2011, 06:07 PM
i bet i could have gotten another year out of it..:)

Pete VanderLaan
03-11-2011, 06:51 PM
And you can use the cords it produces to map constellations. You may just be surprised at how nice your glass is when you actually replace it. Leaks are not the only criteria for replacing a pot.

Eben Horton
03-11-2011, 07:48 PM
what cords??? i rarely had any issues with them, and when i did, i would simply clean the pot.

THe furnace gods call me Johhny magic:):):):):):):)

Eben Horton
03-12-2011, 07:09 PM
It still has the damn writing on it...:)

David Patchen
03-12-2011, 09:21 PM
When ppl calculate the cost vs. savings of switching from batch (high cook temps) to cullet, the pot's long life should factor into it. Pretty amazing.

Pete VanderLaan
03-13-2011, 06:55 AM
well, six years ago I was a major enthusiast on those pots. A lot changed. What you say about batch and cullet is true but I do believe Eben uses SP87. He has simply been careful and very lucky. I've seen this happen a few times with every manufacturer. I still change my pots every 70-90 cycles more for the glass quality than anything. You think it's making OK glass since the day to day changes are imperceptible. It's really not. The stencil is iron oxide and they do last forever if they don't get slopped on.

Patrick Casanova
03-14-2011, 06:30 PM
Eben,
Had you been batching at the lower temps the entire time? Or did you switch along the way? Where does your burner enter the chamber above the pot or below? Thanks!

Eben Horton
03-14-2011, 06:55 PM
i pretty much built my furnace after a John Chiles design... Burner is above the pot. Flu is down low behind the pot.

I have always charged cold. 2250 tops. It takes longer. Oh and i always dumped the batch right in the center of the pot- trying not to touch the sides

if you look at the first picture i posted, you can see that i wore grove on the pot from gathering.. :)

Patrick Casanova
03-14-2011, 09:48 PM
Charge at 2250 and cook at 2325?

Pete VanderLaan
03-15-2011, 05:26 AM
if you look at the first picture i posted, you can see that i wore grove on the pot from gathering.. :)
*****************
Peet Robison did that and I advised him to shut down and rotate the pot.

Eben Horton
03-15-2011, 09:09 AM
Charge at 2250 and cook at 2325?

I cook at 2280 for 7 hours

Peter Bowles
03-15-2011, 09:27 AM
Similar here, I melt at 1200 and cook at 1245 for 6.5 hours and have just gotten six years from a pot melting 40-50 melts a year.

Eben, you might notice how much smaller your replacement pot will be in terms of capacity.....I know we did.

Eben Horton
03-15-2011, 07:56 PM
Peter, trust me i am going to notice a huge difference- i am downsizing my furance!!

Allan Gott
03-15-2011, 08:12 PM
Did that furnace just get back from Japan or what??????

Patrick Casanova
03-15-2011, 08:24 PM
And finally Eben... do you stir or use a potato to stir, and when?

I use SP as well and because of this board I've been working my way down in temp. I try to never get above 2320 during my cook... my glass has been better. My pot life has gone up and my gas bill has gone down.

I'm one who fires with my burner below the pot. I built my furnace almost 14 years ago. It is based on Wes's design in Henry's book with a couple of small modifications. Knock on wood, I have never had a problem with flame impingement. No spalling. No cracking. The only difference between one place on a used pot and another is the gathering/charging dribble.

I don't know if Wes is still firing that way or not. I know he rebuilt after I visited. I'd do it again.

Eben Horton
03-15-2011, 08:40 PM
process is this-
The day before I charge, I ramp furnace to be at 2250 at 6 AM... start charging around 8 or 9.. Furnace will drop to around 2100... after the first bag- i stir with an old punty- After i throw in one bag, and once its completely melted, i stir- This mixes the old glass with the new glass, then i add a bag every hour/ hour and a half until its full.. i only add batch until the previous bag has turned into glass.. when i have thrown in the last bag, i advance the program on the partlow to go to 2280 in one minute, and hold for 7 or 8 hours, and then crash to 1900

I have perfect glass in the morning with an occasional pool of Salmon egg bubbles..

Pete VanderLaan
03-16-2011, 02:35 AM
Peter, trust me i am going to notice a huge difference- i am downsizing my furance!!
***************
nice lawnchair!

Andrew Boatman
03-17-2011, 11:32 AM
Here is my six year crown. Crack running from element hole to element hole, and one going to the front of the crown.
So just a pre-thinking remodel reminder. Order crucible, order elements, order crown just in case. Be ready.
Crucible had a crack and there is a goodly amount of glass at the bottom of the furnace too.
https://picasaweb.google.com/aboatman/Furnace#

Kenny Pieper
03-17-2011, 04:04 PM
Andrew what happened to those elements?

Pete VanderLaan
03-17-2011, 04:22 PM
I'm waiting to hear about the elements... Andrew ordered spares a month back. I looked at those photos Andrew and they are hard to read up close but I'm not entirely convinced tht you couldn't use that crown one more time. Did it come out in pieces, or as a unit?

Another part I want to encourage people to have is the bussblock which connects the "0000" cable, or the 350mm cable to the element banks. If it does overheat at all, you're never going to get the Allen bolt to loosen up. It will just strip out. That in turn pretty much involves replacing the two straps leading from the bussblock to the first element in the bank.
I have done this twice this year. The first time, I did not have spares. The second time I did. It is not expensive at all but you are not going to get the part off the shelf easily. 25.00 bucks would cover all the parts I think.

Scott Novota
03-17-2011, 04:30 PM
Pete you should but together a "Moly Shelf Pack" that has all the little things that are not horribly expensive unless you don't have them on the shelf.

I have no idea what those might be but I am sure you do.

Andrew Boatman
03-17-2011, 04:39 PM
I am not sure what the BussLock is, can you elaborate?

I have a full set of elements just in case. I got one out without trouble and we broke three and left two in there instead of tweaking them out with risk of breaking them.

We started looking at taking off the top. We knew we needed to change out the gathering port and it is a huge piece. We decided to take off the side panels and open it that way. The furnace looks like a dissected frog. This method worked well.

The crown crack was a concern for Steve in that it goes all the way across. getting another couple of years out of the crown would be great. Fear of it coming down was reason to change it out. I would certainly like to keep it if possible.

Pete VanderLaan
03-17-2011, 04:56 PM
BussBlock, not busslock. It's the big aluminum lug that connects the big cables from the transformer to the straps leading to the elements.

If you can actually get the mess changed out without moving the crown I think you will get away with it. I prefer arched crowns. You can see why.

Pete VanderLaan
03-17-2011, 04:59 PM
Pete you should but together a "Moly Shelf Pack" that has all the little things that are not horribly expensive unless you don't have them on the shelf.

I have no idea what those might be but I am sure you do.
*******
This is just so much like MGB's. I'm learning as I go. I just know I keep creaming the bussblocks and you will not find them at Home depot. And Andy, Noalox the snot out of everything but the actual elements.

Jordan Kube
03-17-2011, 06:14 PM
How/what are you charging to get that stuff all over the inside of your furnace? How did you break those elements?

Pete VanderLaan
03-17-2011, 07:54 PM
Do you by any chance charge in paper bags? I know you use spruce Pine batch. I was so busy looking at the crack in the crown, I didn't see the garbage.

Andrew Boatman
03-18-2011, 02:15 PM
I did not know that the crystalline build up was not normal. We are using Spruce Pine with Texas Sand in 12.5 lb. bags. Pete thought maybe it is the bag itself. We get a lot of dust when tossing in the bags and I figured the dust was just building up and building up over time.

One element broke when trying to remove it and two broke due to user error, the famous I D Ten T error.

John Riepma
03-18-2011, 04:33 PM
It's the Texas sand batch that builds up on the elements. It does fine out real nice but it's very dusty and tends to stick the door shut after charging. We switched to it for a couple of pallets and now we've switched back. It just wasn't worth all the dust and door problems to get slightly better glass. The regular SP87 w/ER does fine for us.

Andrew Boatman
03-18-2011, 05:56 PM
The door gets awful sticky. I will switch after this next palette.
Thanks for the info.

Tom Littleton
03-19-2011, 12:39 AM
The last guy that called me about dust from the 12.5 lb bags was literally throwing them into the furnace, causing them to explode and get dust all over. His flue was getting clogged and he was looking for someone to blame, the batch or the furnace designer. Placing the bags on a ladle and gently putting them into the furnace would have gone a long was to solving his problem. I always think of him when someone says "tossing" and wonder.

David Russell
03-19-2011, 08:42 AM
for what ever its worth, i have been told in the past by brent to never charge moly elements with batch in paper bags. he said he had seen this cause problems but since this was not my situation he did not elaborate............

John Riepma
03-19-2011, 09:25 AM
The door on our moly furnace pops out from about a 3/8" deep detent when we open it and we usually leave it cracked open about 1" off the detent until the flames from the bags die down. There is a lot of flame that comes out for a couple of minutes until the bags burn off, and there is a lot of flame turbulence when you charge with the paper bags. It's been discussed at length in other posts that it's a good idea to vent a moly when charging. Since there isn't a vent on (most) molys it has to go out somewhere and that's how we've decided to vent it. It's just seems to me that the TS batch is finer and thus more prone to getting airborne from the turbulence, but I haven't actualy had my eyeballs in there to watch it, just guessing about what was causing what I've observed. I don't think that the buildup on the elements affects their performance in any way, they all look red-hot when running. Having said all that I also need to say that the 12.5# bags are a great way to handle the charging and the minor issues we had with dust/sticking were easy to deal with, it's just easier with the SP87 for our purposes. I would never switch to anything else from the SP batch.

Pete VanderLaan
03-19-2011, 09:32 AM
I don't recommend using bags at all anymore in electric units.

Andrew Boatman
03-19-2011, 10:11 AM
I have started dunking the bags in water before putting them on the shovel to put into the tank. This did seem to help the dusting.

how then do you add glass to the furnace without the bag?

Jordan Kube
03-19-2011, 02:44 PM
Bags will do that in an electric furnace.

Pete VanderLaan
03-19-2011, 02:59 PM
I have started dunking the bags in water before putting them on the shovel to put into the tank. This did seem to help the dusting.

how then do you add glass to the furnace without the bag?
Either a ladle, or a long steel tray. I ladle.

David Patchen
03-19-2011, 04:14 PM
Our shop uses long troughs with handles on the back. Easy to load w/batch and easy to dump into the pot.

Pete VanderLaan
03-19-2011, 04:26 PM
I would not think the bags would cause the problem just by themselves. It may be that coupled up with batch dust that they grab and hold the dust and it seems to fuse together up at the elements.

Eben Horton
03-19-2011, 05:57 PM
I have a wood stove chimney pipe with an end cap on one end. Open a sp bag, pour batch in the tube.. Open the door, and bombs away... Right in the center of the pot.

Jordan Kube
03-19-2011, 06:27 PM
I wasn't very clear. The bags catch fire and blow the batch around.

Doug Sheridan
03-19-2011, 07:53 PM
Those bags, designed to lessen dust, create more, imho. And it costs more to boot! After one pallet of 12 lb bags, I was done.

Pete VanderLaan
03-20-2011, 06:36 AM
While I'm not sure if this is where SP started to offer small bags,, I introduced Tom to putting it in bags when he took my color class a long time back. Chuck Savoie started me on it. We were trying to load a furnace with a ton of little pots and beer bags were the best way to get the batch in the pots without spillage.

I think there are good and bad sides to using them. For shops where dusting is an issue in general, I can see where they are a good thing. They are a total drag in an electric furnace. It's like running an incinerator. It just stays and stays. When I developed the formulas for the corona glass at Simpson's, we sent the formula off to Tom to mix it by the ton and put it in 12 lb bags which given the painfully inadequate batch room at Josh's made it easier for me to set up the colors. It was like working in a broom closet. So, I didn't chuck the bags in the pots at all, I just decanted from them.

Rollin Karg
03-20-2011, 07:54 AM
It probably depends on the size of the pot and How full it is. If it's big and empty, how you load is not so critical. As the pot fills and you get near the rim then you want to be more careful. Throw a bag into an almost full pot and you're going to get batch on the walls and elements. The batch eats the walls that's not good for you, although HB might like it. As for the elements, it's not a big deal while they're hot but it can be when they get older and more fragile and you go through the cool/heat cycle when changing a pot. I think the differences in expansion between the Moly element and the glass gets to be an issue.

Pete VanderLaan
03-20-2011, 07:58 AM
I am just thinking out loud here but it seems to me that the surface of the element should be so hot as to shed any recognizable glasses. I would think it would retain quartz quite well. That stuff I see looks like a sort of quartzcrete and it is certainly hard stuff. I don't know if it is crystaline. I don't have a clue what the expansion of a silicate with moylbdenum has. It surely must have one though.

Gabriel Cole
03-24-2011, 07:06 AM
I just got my first EC pot. 5099. Looks like a better size config (lower + wider) then my previous LC 189s. BUT i am so surprised at the lack of finnish around the rim. all chipped and dinged. Seems to be a much coarser material then the LC pots and maybe that's an advantage.
I got near 100 melts and 3 years out of an LC pot and it came out looking fine, like Ebans. My last LC however went only 10 Months and 15 melts and nearly cracked in two. such a crap shoot.

Pete VanderLaan
03-24-2011, 07:18 AM
Grain size was the entire point of my conversation with you. The finer the grain, the more likely the thermal shock capacity but will melt hotter. The coarser the grain, the less thermal shock but the lower resistance to high melt temps. I wish EC had the same quality it had six years ago, but it doesn't. These days there are patches and voids are all too common.

Lawrence Ruskin
03-27-2011, 07:31 PM
Like David and Eban said, just load the stuff into a tube,if you're using cullet you can wash it and heat it before you dump it, but with a tube it's one shake and it's right in the center of the pot.

Ive been doing this for 25 years, it's deadly accurate.

And Fast...

Lawrence Duckworth
03-10-2012, 10:05 PM
process is this-
The day before I charge, I ramp furnace to be at 2250 at 6 AM... start charging around 8 or 9.. Furnace will drop to around 2100... after the first bag- i stir with an old punty- After i throw in one bag, and once its completely melted, i stir- This mixes the old glass with the new glass, then i add a bag every hour/ hour and a half until its full.. i only add batch until the previous bag has turned into glass.. when i have thrown in the last bag, i advance the program on the partlow to go to 2280 in one minute, and hold for 7 or 8 hours, and then crash to 1900

I have perfect glass in the morning with an occasional pool of Salmon egg bubbles..

my 200lb pot has been through 14 SP87 batch cycles...and the last couple of batchesI've started to notice some stuff that looks like a gob of
snot or a flem loogie when gathering either the first or last of thebatch, is this the "cord" or salmon egg you guys speak of? I melted a couple of scrap/cullet pots awhile back but have since melted only 100% sp87.I'll get the pot dang near empty before a recharge too.

I charge @ 2250f, cook @ 2350/6hrs squeeze @1950...half a bag an hr., no mixing, i center the mix and flatten the top, some of it does touch the sidewall of the pot though.

any advice?....is this where the potato trickcomes in?

Rollin Karg
03-11-2012, 04:35 AM
Make sure you empty the pot occasionally and yes do the potato.

Pete VanderLaan
03-11-2012, 06:54 AM
I would also question how long you take to go through a pot full of glass and at what temperature you leave the pot at when you are not working as well as what temp when you are working.

You could be starting to change your charge schedules without realizing it. The charges need to go absolutely flat before the next charge. Rollin is right. Do the potato. A nice big Russet on a punty you absolutely hate. Take it to the bottom of the pot when it is really hot and move it around the wall which you will be able to feel. It will last about thirty seconds max. So will you. Wear heat protection.

Josh Bernbaum
03-11-2012, 10:49 AM
You have a 200# moly, right Lawrence?

In mine, and I melt SP87, I do a full 50# bag each load (fill my charging chute twice).

With my 15kW set up, it takes slightly over 2 hrs. for previous charge to go flat. (would be nice to have a bit more juice for melting actually)

I've been charging at 2275, and after last load goes in I'm cooking at 2300.

I potato like Pete and Rollin say after 5 hrs. at 2300 and turn down to squeeze temp (2000) at 6hrs.

I can only recommend this because it's getting me good glass in MY furnace, but may be worth trying to see if it works for you. My 5-6 hr. cook was originally decided by looking at the glass like Pete recommends (larger bubbles with clear space between them).

Hope that may help.

PS, I think 2350 cook is a bit hotter than you need for SP and just wasting some electricity and refractory life in my opinion.

Lawrence Duckworth
03-11-2012, 10:51 AM
Rollin I empty the pot to about 1 inch from the bottom usually and thought maybe I might be scraping some of the pot with the pipes n punties. also thought I might be draggin shit in there on the punties n pipes.

I've emptied a pot in three days twice. Yeah, It was a wild ass guess as to what size furnace to build, but the newness has faded some so its a lill slower now.
I work at rookie temp of 2000f and leave it at that overnight too. I have worked at 2020 and 2050 but seems better for me right now at 2000. However, Im sure I've been dragging some Borax in lately and that does seem to help with viscosity-(sp?), maybe its time to to go up a bit in temp.

Anyway, thanks guys....i'll wipe it with the potato....the potato disappears...right?? :)

Lawrence Duckworth
03-11-2012, 11:10 AM
Y

I potato like Pete and Rollin say after 5 hrs. at 2300 and turn down to squeeze temp (2000.

Not every batch though do you????

maybe I don't understand the potato thing fully. I thought it was just to clean the pot

Pete VanderLaan
03-11-2012, 12:06 PM
maybe I don't understand the potato thing fully.
***********
Lunch!

OK no that's not it and eating it sucks actually, having tried it. It's very raw in the center. NO DON"T LEAVE THE POTATO IN THERE. Stick it way down in HOT glass for about thirty seconds moving it around on the PUNTY you no longer care about cuz it's gonna look like crap when this is over. And you don't have to stir your glass every charge but the more you stir it the better it will be. You could stir forever like Steuben did.

Protect your arms and your face. This gets hot.

Lawrence Duckworth
03-12-2012, 07:43 PM
well....I have to admit, I sometimes don't wait for everything to go completely flat. And.....I use the stuff the next day instead of waiting an exxtra day for things to settle in.

5 A.M tomorrow, I'll try again:)

Rollin, I cleaned the pot down to the bone today, what % risk of cracking the pot going that low?

Rollin Karg
03-12-2012, 08:08 PM
Rollin, I cleaned the pot down to the bone today, what % risk of cracking the pot going that low?

Zero as long as it stays hot. Be a little cautious about the size of the first load when it gets completely empty. In our furnace we load two to three 24 pound bags at a time. If it's completely empty then two only.

Pete VanderLaan
03-13-2012, 04:34 AM
well....I have to admit, I sometimes don't wait for everything to go completely flat.

********************
Bingo. Your problem is right there.

Virgil Jones
03-13-2012, 05:31 AM
Zero as long as it stays hot. Be a little cautious about the size of the first load when it gets completely empty. In our furnace we load two to three 24 pound bags at a time. If it's completely empty then two only.

Rollin, If I remember right you make your own batch. Are you putting in a charge...bag and all?

Rollin Karg
03-13-2012, 07:09 AM
Rollin, If I remember right you make your own batch. Are you putting in a charge...bag and all?

Yes,it makes it easy.

Pete VanderLaan
03-13-2012, 07:38 AM
three bags for 24 lbs converts to six 12 lb bags. It's more bag material. I found the bags to be somewhat of a nuisance back in Santa Fe in the non vented electric furnace. I never found that it was actually bad for the equipment. I don't use bags now but it does keep the mess controlled on the shop floor. Penland used to design furnaces to take full fity pound bags through the door.

I just about always use a ladle now and need to make up a smaller ladle for the class since it will use 7 inch pots. Cross contamination is a big issue in color making.