Schott delaminating?

[menty666]

I was working with some thicker Schott clear rod today and I found that when it checks from being reintroduced into the flame, it delaminates; pieces will peal off in that section like mica. At one point I even noticed a section that was slightly bubbled like a skin blister. It's weird.


It's thicker rod, so I assume there's still a lot of manufacturing stress in it, but it kind of sucks. Even when the surface checking happens, it almost looks like tempered glass.

[Greymatter Glass]

happens with all larger rod I've used....

something to do with the way the rods are made I suspect, the strain is coaxial and layered sort of like onion skin. I've had marbles that weren't properly annealed do the same when reheated too quickly.

[hashmasta-kut]

haven't seen it on the box of 20mm simax i have been using.

[menty666]

I rarely see it in the 18mm I use, so I suspect, like mentioned, it's particular to larger stock. This was 40mm I was working with :)

Or was it 36? Pretty sure it's 40, but I'll have to check the box; been a while since I ordered it, but it's not small.

In most cases I can strip it and continue on without any worries, but it's a hassle.


edit, I checked with the calipers, it's 40. Good too since that's what I just re-ordered :D

[ThreeE]

40mm rod! What are you making??

[menty666]

Dillies and plugs ahead of an event this spring. I'm going to have arms like Popeye by the time I finish.

[Mike_Aurelius]

Waaaaayyyy back when, I remember someone commenting about this and saying that they would "skin" the rod to strip off the surface layer.

[SkoGlass]

40mm for flat cane!! Don't remember seeing this but I can look next time we do a pull

[istandalone24/7]

Waaaaayyyy back when, I remember someone commenting about this and saying that they would "skin" the rod to strip off the surface layer.

i have to do this with every marble i make lately. i ordered a case of simax 28mm from (retailer not mentioned, as i dont' believe it was their fault and they made it right) _____ and it came in with one piece of the 28mm broken, which in turn abraded all the other pieces in the case. god i love wasting oxy and 4mm to peel it down haha. they made it right.

but the next case i ordered (by accident mind you, must have been in my shopping cart previously) i opened up and it's pristine. i revel in the fact that my peeling days are almost over, and can't wait to start using this good stuff.

[Greymatter Glass]

I skin every rod if I am using it for a lens. Even "pristine" glass from a new case has surface imperfections from manufacturing, and I figure I'd rather just skin it no matter what. It's a practice I picked up watching marble makers much better than myself, and I have to say, it vastly improved the quality of most of my lenses. With practice I can skin 4-5 inches of a 26mm rod in 2-3 minutes, and not lose more than 10% of the glass.