Sandblasting, does it cause a problem?

[menty666]

I have something I want to put a matte finish on via blasting. I'm curious though, does this make the piece weaker by introducing a slew of micro scratches on the surface?

edit: I forgot to say, solid glass, not hollow.

[Trevor]

im fairly new to lampwork but ive been grinding and polishing glass for about ten years (im a glazer)
in my experience it does not weaken the glass. ive had many a mirror break, but never one that ran from the grind. flat glass my be different though...

[Pogo]

^I disagree. I've been blasting LOTS of boro recently... Had some of the veterans explain that much stress is induced, and that re-annealing after blasting is STRONGLY recommended.

[Trevor]

flat glass isnt boro anyway so i guess it wasnt very relevent, srry

[atomgirl]

boro is not very different than soft glass.

yes, it adds stress. ur making the glass thinner too

[atomgirl]

also just think, you're beating it with a stream of little rocks for like 20 minutes
of course glass hates that. dont let it haet u

[Pogo]

OP never states he is using boro specifically. I stated that I have been blasting boro.

Also, all opinions are welcome and relevant. The fact that you state you have personal experience over a long period of time gives more clout to your argument...

More factors may need to be taken into account to satisfy the answer of our resident borovangelist. What's the end product going to be or be used for? How thick of a solid is it? Are there load bearing points on the piece itself (such as a top-heavy sculpture, etc.)? Is it going to be heated and cooled repeatedly (scientific or smoking tool) or inserted into the body(dildo)?

Some applications (flat glass, thick decorative work, etc.) may not need re-annealing to last a long time. An ounce of prevention is worth a pound of cure, though, and pending your art is conducive to successive re-heating I'd suggest doing it.

[atomgirl]

poho wat r u a phd

[Mr.P0rn]

I'm with Pogo, I would suggest re annealing anyway, just to be safe.

[menty666]

Yup, it's boro (and btw, you can get boro sheet/flat glass (http://howardglassco.thomasnet.com/viewitems/schott-borofloat-glass/schott-borofloat-glass-2?&forward=1))

I'm making a back scratcher but it's going to have a joint in it. The pieces range in thickness from about 14mm to 18mm.

I think blasting it'll look nice, but I don't want someone to accidentally crack the darn thing while using it and shiv themselves, ya know?

Reannealing won't be a problem, but I may just leave it shiny to err on the side of caution.

Thanks!

edit: Oh, and I'm worried more about microfractures like when we score and snap than embedded stress.

[kage]

poho wat r u a phd

little early on the drinky or you just trying to fit all that on a license plate?

[menty666]

little early on the drinky or you just trying to fit all that on a license plate?

I think someone told her we charge by the letter around here.

[atomgirl]

lol im on my fone

[ACE]

i've been sandblasting since 2003 and i've never felt that any piece i've made has broken or been less structurally sound due to sandblasting. to my knowledge sandblasting does not cause micro fractures, although one time i noticed one of my pieces was cracked during sandblasting and hitting it with the sand made it worse for sure lol.

[Aaron Ellis]

poho wat r u a phd

Poho hahaha jkhms

[Aaron Ellis]

I've been wanting to do some blasting and always wondered the same thing. I have heard the same about anealing after blasting tho.

[Pogo]

"po-ho" is actually an accepted pronunciation, which I'm sure atomgirl randomly fell upon. I've been referred to many times by this from my friends, so nothing new. Actually was given a lighter with "Pojo (poh-joe) " on it as well.

Also known as Pogeezy, Pogurt, Pogahontas, etc.

Haters gonna Hate....
All about the Pog-Swag.

[Aaron Ellis]

No hating here. I love it.

[ALIEN!]

Vegas is full of poho's

[Swampy]

Tom I remember someone did a scientific comparison on the Warmglass board in about 2001 or something.

Just spent a while searching (might have been Tony Smith or Steve Immerman, they had the facilities...) to no avail.

I think they reformatted the forum in 2003 and some of the old knowledge got resorted...

There is definitely a difference between the damage that silicon carbide and aluminium oxide inflicts on the surface, I think alox 'beats' it and silcarb cuts it. Either way I'd anneal afterwards if it's for a body insertion item.

[menty666]

Thanks! I need to look, I think I've got the aluminum out in the shop.

I'll make sure it gets a full vacation in the kiln. Heat for the scratcher, rum drinks for me.