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Steve Stadelman 05-01-2009 10:50 PM

That's my guess also. The crating guy is usually same day, the only holdup is the availability of the crucibles.

Pete VanderLaan 05-02-2009 07:26 AM


Originally Posted by Steve Stadelman (Post 79757)
the only holdup is the availability of the crucibles.

Which have to be ordered before they can be shipped. (Wink Wink, Nod Nod, nudge nudge)

Greg Gepp 05-05-2009 11:14 AM

Hi guys, mmmm ... since when did I become a guest ?
I seem to have been dumped from the site again Pete so I re-registered with my same details and while my posts are still on this forum, (though they're now n/a), I've been demoted to guest. I sent a letter to admin so I'm repeating myself somewhat, please excuse using this page for my grumbling instead of help pages.
I'll ask a page relevant question : three weeks to Melbourne sounds very speedy, can you confirm that ? Order coming soon, I'm still negotiating with people to maximise the order.

Steve Stadelman 05-05-2009 11:47 AM

I have been told 3 weeks. I believe it. We can commonly have stuff down there in that time period.

Pete VanderLaan 05-05-2009 11:59 AM

Of course I can't guarantee it. If you want air freight it will cost a lot more. Ships are ships. Three weeks is our normal experience. if delivery guarantee is a requisite for the order then you should order it elsewhere. Normal lead time from either LaClede or Engineered is four weeks minimum anyway. High Temp is the only one that regularly stocks inventory.

Pete VanderLaan 11-20-2009 05:46 PM


Slate Grove 03-10-2010 07:38 AM


I'm wondering if the 2) 14.5" crucibles you sen me for our new color furnace will handle opals? The furnace arrived last night and we'll be installing today...planning on starting anew post with pics of the beautiful little furnace in the next couple of days.



Pete VanderLaan 03-10-2010 08:36 AM

Well, they handle them as well as any other good high alumina pot will handle them Slate. It isn't fluorine that is hard on a crucible, it's low viscosity.. When I melt opals at about six percent flurorine, I never let the furnace get hotter than 2200F which yield a viscosity similar to that of SP87 at about 2415F. When you look at issues like silver metal drilling a crucible, it's the fact that the metal is like water. There's nothing special about the silver. Think what would happen if you melted SP87 at 2550F. It attacks the porosity of the pots.

I forget who said it ( Fritz would now give me a huge lecture), but it is "think of glass as the universal solvent."

I know that Croucher gets about 25 melts from a fluorine alumina pot as opposed to about 40 melts for his lead transparents in AZS. The price difference is huge. And it's
always a crap shoot.

Slate Grove 03-10-2010 01:05 PM

Thank you Pete!!! That makes total sense.

Slate Grove 03-10-2010 05:25 PM

Pete, what's the cost on those pots? The first 2 were included in the furnace cost for us, and I'm going to need to order some backups?



Pete VanderLaan 03-10-2010 06:24 PM

If I recall correctly you have the 14.5 inch pot which runs 280.00 each.From High Temp, They ship fed ex freight in multiples and UPS for singles and we always have them in stock.

Slate Grove 03-11-2010 07:33 AM

You are correct Pete, they are the 14.5" pots. Thanks for the info, I'll get the paperwork together in the next week. Thanks

Pete VanderLaan 03-11-2010 08:50 AM

You can order them on-line Slate. We will still need a personal contact for the credit card v code but try

Justin Thompson 07-20-2010 02:33 PM

11" crucible

I am thoroughly pleased and pleasantly surprised at how much workable glass I can pull from Hi-Temp's 11" crucible; however, I must being doing something wrong (I usually am).

In the last 6 months, I have gone through 2 pots and am currently running a cracked one that has a creatively monstrous Gerri-rig applied to it (you don't wanna know the details, but some hi-temp cement and a kiln shelf is involved)

At $160 a pot, it isn't the end of the world to replace one, but it adds up and money is hard to come by these days. (I just moved my studio and moving never costs what you expect it to).

Anyway.....I think that I have been OVERLY careful when ramping down and candling up the pot.....but; like I said, I seem to be going through pots unusually quick.

Do you have a ramping cycle (or stress range) for the Hi-Temp pots? I am pretty new at owning a studio; however, I have worked in plenty of other people's studios as the person in charge of costing them money. Lol, you really don't get a feel for how much things cost until the bills have your name on it. :) (Never before now did I realize the value of sorting through crack-offs and lip trims to recycle) =D

Anyway....anything would be helpful.....I shouldn't be going through a pot every 3-4 months, should I?

Pete VanderLaan 07-20-2010 05:41 PM

No, you shouldn't go through pots that quick but it's entirely possible to do it. You don't give out a boatload of important information:

Is the furnace gas or electric.
If gas, where's the burner?
If electric, how far from the elements is the pot?

What heat up schedule do you use now? The whole schedule please.
What turn down rate do you use.
Is the pot full or empty or hald way when you shut down.
How often do you turn it on and off.
What do you melt?
What temp do you melt at?
How often do you melt?

If our crucibles were lasting as long as you describe in general, I wouldn't have much of a business. Your experience suggests that you are doing at least one and maybe more than one thing in an unfriendly way to the pot. I like to see a pot in my own shop run about 70 cycles, perhaps 90 based on melting at about 2250F and turning the furnace up to 2375 for five hours after the melt cycle is complete. Sometimes ( With the black) I go up to 2410F which Is hard on the pots but they are still putting out.

Time is really irrelevant in melting life. The number of times you go up to temperature and down again is the significant figure here. If you were melting five times a week for 12 weeks that would be 60 melts. If it were being turned on and off, that would do damage to the pot and shorten its life so 60 or less would not surprise me. I think ideally in a studio you want to have enough glass to run for five days and then recharge. That makes for a 70 cycle pot to last over a year and that is what the bulk of my clients get. BUT how you treat it is really significant.

Scott Novota 07-21-2010 01:14 PM

This simple answer based on what I know about my wire melter over the years is that every time it is ramped down you risk cracking it.

I went though 2 pots in the first 6 months because I was doing up and down.

Once I started to cycle down to 1400f (25f every hour down to 1400) when I was not working for a week instead of turning it all the way down the pot lasted 3 years. You pay one way or the other as Pete likes to say "no free lunch".


Justin Thompson 07-21-2010 06:13 PM


Thank you for the info. I was actually not thinking in terms of melting cycles as it effects the life of the pot. I know that makes me sound ignorant; however, in this case...I guess I am. To think of a pot's life in terms of melting cycles; it makes a lot more sense and helps me to think in a different way. As I said, I am pretty new to owning my own studio and being responsible for things like this. My experience with pot furnaces has always been 200lb and above sized pots, and those usually experienced a death as a result of pitting and detereoration. I haven't had much experience with cracked crucibles.

The information that I left out.....

I run a wiremelter (an AIM 1411) and the pot sits about 2.75-3 inches away from the element groove (so about 3-3.25 inches away from the element itself). I have added a layer of soft brick to the sides, so that the elements aren't sitting 1.5 inches from the floor of the furnace (a very poor design IMHO). Because of the added layer of 2300F brick, I have had to elevate the pot about 3 inches off the floor.

I keep the furnace idled at 1900 when not working. When working, I ramp it up (usually over 1.5 hours) to 2160. The furnace stays at 1900 (or above) 24/7. Since I am mainly teaching and doing about 2 days of small production, I find myself charging about once every 4-5 days. During the melt, I ramp it up to 2200 (usually after a day of blowing, so the furnace is already at 2160). BTW, I melt System96 nuggets. I charge at 2200 (usually about 8 lbs/charge cuz of the size of the pot). After the charge, I ramp up to 2300 and soak for 4 hours. From 2300-1900, I run an 8 hour ramp down.

When I have had to turn it down to do maintainance, I usually ramp the pot down over about 4 days. I, of course, ramp it down with a fully empty pot. I pay special attention to the pot during its ramp from 1400-800, usually with a hold and soak at 1400 (for 10 hours) and 1000 (for another 10 hours). I do this because I have been told that the pot is most fragile (to heat) in the range from 800-1400 degrees. There was only one time that I wasn't able to fully empty a pot before a turn-down. I blew an element (on the old 1411's, there are only two sets of elements, so one element isn't able to sustain above 1600). So, I came in to find the furnace at 1600, with about 1/4 pot full of glass. Since I didn't have a torch small enough to fit in the peep hole, I had to ramp the pot down being 1/4 way full. Again, I was careful to ramp down between 1400-800.

The furnace pretty much stays on 24/7 for about 4 months at a time (my elements usually have a life of 4 months), then I need to ramp down to switch out. I have been pretty good at being able to catch the elements in time, before they pop and am forced to ramp the furnace down, as is.

I hope that you don't find my knowledge (or lack there of) too comical and can offer a bit of advice on the ramping schedule for both charging and for the turn-down for maintainance.

Thank you.

Pete VanderLaan 07-21-2010 09:01 PM

How is the pot supported?

And, that's really pretty hot for system 96. It would be seriously fluid at 2300F which can really wear on a pot. Most people in wire melters melt that stuff at about 2175 and it's pretty much good to go the next day. Viscosity of your glass is a big factor.

Justin Thompson 07-22-2010 10:42 AM

The pot sits on top of a 1/2" kiln shelf; which in turn, is elevated by a tripod of soft brick.

I guess I thought that the system96 needed to hit that high to fully melt, but I guess that would defeat one of the reasons why nuggets were developed in the first place, huh. I haven't seen much pitting on my pots, so I didn't think that there was much deteroration going on; however, I guess if the glass is liquid enough, it could penetrate a hairline and make it a much bigger issue, huh?

Thank you for the info......

This board is an awesome resource.

Pete VanderLaan 07-22-2010 01:44 PM

The support sounds good. Turn your melt down. Avoid shutdowns. I think the observation about turning it way down instead of off costs a lot less than replacing pots is a good one.. Just stay above 1100F.

Crucibles are really pretty tough but strength is really relative. It's always a trade off. When you melt a glass like 96, you get a very fluid glass at 2300F- too fluid. The wear on the pot is notable. It's really similar to Fluorine glasses. They aren't any more caustic than anything else. It's the low viscosity that the fluorines ( and the 96) have at regular working temps for a conventional soda lime that eat up your refractories. Imagine taking SP87 up to 2500F. The viscosities would be similar , the wear substantial. Glass really is the universal solvent.

Tom Fuhrman 07-22-2010 02:03 PM

I never take my wire melter over 2160 and melt all types of cullet very easily. going higher is needless and foreshortens the life of the crucible and the elements. elements aren't really rated to sustain heat above 2200 for any long length of time. I think we hashed this out many months ago on some other threads.
I can get a year out of my elements most of the time and much more than that out of my crucibles.

Justin Thompson 07-22-2010 02:09 PM

Pete and Tom......

Thank you very much for the advice. If I could get a year+ out of my elements, I would be a very happy camper.

Before I switched over to nuggets, I was only familiar with furnaces melting batch; so, when someone told me that I would get a nice melt by soaking nuggets @ 2300, it made somewhat sense to me (due to my knowledge based in batch language). I guess if I would have thought about it for a second, I would have realized that one of the advantages of nuggets is the lower melt temp.

Oh well....I guess that is one reason why this board exists. Thank you Peter, btw.

I just can't wait for the day when my studio justifies me upgrading to a furnace where I can run Moly elements, instead of a wiremelter......err, wait....maybe I can wait. :)

Pete VanderLaan 07-22-2010 02:43 PM


Originally Posted by Justin Thompson (Post 89757)
Pete and Tom......

Thank you very much for the advice. If I could get a year+ out of my elements, I would be a very happy camper.


You probably would get that kind of life if you didn't exceed 2175F, which was actually the whole point behind the system 96 nuggets.
I just did the benchmark melting for the new SP87 Chips and it melted very nicely at 2175F. The trouble with the Spectrum has been the boron which dissolves any of the fireclay or silicate components of your furnace.

Scott Novota 07-22-2010 11:29 PM


I have the newer version of your furnace with the 3 elements. I have run it for 3 years now with the same crucible.

Now, I know it is on it's last leg at this point. Some of the things that I can tell you from my experience are the following:

#1. The dp connector needs to be replaced with every element replacement. It proved to shorten the life of the elements if I left the old one in the furnace. Hell you can buy them in bulk for like 9 bucks each or just switch them to a merc. Either way I stuck with the DP because it proved to go to 80% about two weeks before my element would go. It was like a shot across the bow.

#2. I could get exactly 13 months out of a dp/element set if I never powered down.

#3. The nuggets ate a channel into the soft brick and created a vent. I plug it with a fiberboard plug when not charging. Leave it open while charging it wants out I want it out it gets out.

#4. I work at 2150. I charge at 2150. I work at 5pm to around 9pm at night. If I charge 15 lbs when I am done, go in take a shower have a beer, come out drop in 15lbs more about 1 hour later I can keep my pot topped off. I will loose around 10% a night until the weekend when I empty it and fill it on sunday. If I toss in my last charge at midnight it will have micro bubbles in the 8am range. If I wait until lunch and look real close I might see some fines, at 4pm it is clear as summer rain.

No need to get fancy. It is such a simple product to melt. I can't wait to melt in my new one that is be built now with SP cullet. I plan to turn the old aim with the old pot into a color pot for a bit then rip it back down and build it up as a 40 lbs pot with the 3 elements. I would really last a lot longer with a smaller foot print. I have two new crucibles waiting on my new ideas.


Pete VanderLaan 09-08-2011 09:51 AM

After almost four years, Effective Sept 19th, High Temp will have a 3.5 percent price increase on crucibles across the board. So, if you want a pot at the old prices, now is the time. I'll be posting the adjusted prices on Sept 19th.

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