Question for you glass blowing/making folks on repairing cracks

I've got an old glass bong that has a crack running up the side. It's not broken, and it's still watertight, but that crack is still there, and I know it's only going to get worse.

Can it be heated up and "melted" back together? I'd just throw it away, but it has a lot of sentimental value (original owner has passed away).

Surely somebody must know if it can be done..

I would assume a skilled blower could
fix it, but I bet it needs to be kilned.I
want to bend the neck of one of my
tubes and thats where I ran into an
article that said glass needs to be
"cooled" at something like 900 degrees
for a number of hours.

I think it's called annealing. Somebody here must have some experience. I really, really want to save this piece.

One last plea for input, and then I'll quit.

Pretty please, somebody on the forum must know if there's anything that can be done. I'm begging here, people.

glass district has a forum for this type of
question,I guess there are not any blowers
on here.

no u cant heat it back up once its cured ur best bet would be to use a clear epoxy and cover the crack and smooth it out over the top of the crack should stop it from crracking anymore

pilgram said:

I would assume a skilled blower could
fix it, but I bet it needs to be kilned.I
want to bend the neck of one of my
tubes and thats where I ran into an
article that said glass needs to be
"cooled" at something like 900 degrees
for a number of hours.

Click to expand...

after a piece is blown its put in the kiln at around 1500 degrees and its cooled for about 18-24 hours now if u were so enclined you could use the colored glass rods or sticks and melt a line over the crack but with that u gotta be caful not to heat up the bong to much cause then it could shatter under the heat but for all that u need to have rods and a acedylyne torch (sp)

i gotta say pilgrum ur avatar is kinda giving me a mini freak out lol just tell me i dont need to stay in this room lol

skunkpunk13 said:

the search for what?????

Click to expand...

The search for an answer to my question from somebody that actually knows what they are talking about.

sounds like it's time for you to take a trip to the gloryhole.

d.s.m. said:

The search for an answer to my question from somebody that actually knows what they are talking about.

Click to expand...

um yeah i was a glass apprentice a few years back....so im pretty sure i have some understanding of the area but hey if you wanna keep looking untill some one tells you yeah we can do it then you end up with a shatterd bong i guess that will just be to bad......

skunkpunk13 said:

um yeah i was a glass apprentice a few years back....so im pretty sure i have some understanding of the area but hey if you wanna keep looking untill some one tells you yeah we can do it then you end up with a shatterd bong i guess that will just be to bad......

Click to expand...

My reply came out sounding quite rude, and that was not my intention. I apologize.

d.s.m. said:

I've got an old glass bong that has a crack running up the side. It's not broken, and it's still watertight, but that crack is still there, and I know it's only going to get worse.

Can it be heated up and "melted" back together? I'd just throw it away, but it has a lot of sentimental value (original owner has passed away).

Click to expand...

it can be fixed, at a risk though.

borosilicate starts moving at around 1200 degrees. at 1500 degrees it is almost dripping. your piece needs to be "soaked" in a kiln for an hour somewhere around 1050 degrees. and then CAREFULLY brought into a flame. at this point it may or may not explode. a lot depends on the original working of the glass and the quality of it as well.

if it can be brought into the flame without exploding then it should be easily fixable. simply start beyond the crack with a nice penetrating flame and work your way back to it. by starting ahead of the crack you prevent if from traveling any further. it may leave some bubbles behind within the glass, but they won't hurt anything.

it can also be fixed inside the kiln if the person doing it happens to have a small hand torch. put the piece in the kiln for an hour at 1050/1100ish, then open the kiln door and work right inside it. this method will reduce the risk of exploding by quite a bit. it's the first initial "shock" of changing temps that causing it to explode. thew closer the glass is to working temp when you start the better.

try googling "glass blowing" in your area for local artists who may help you. costs can vary drastically.

In my eyes if the piece has enough sentimental value, you may seriously want to consider retiring the piece. Give it a few last bowls, make them memorable, then clean the bong up and display it. Of course since you said it was still water tight I imagine a nice crack running down the side, but nothing thats like damn thats a cracked bong, if its pretty severe then I'd go for the fix

I very much appreciate the replies and advice. My apologies again for being bitchy when nobody gave me the answer I wanted to hear..

Sheskunk, it's not borosilicate, it's cheap glass. Thick, but cheap glass. I think jhopkins34 has the right idea. This thing would never survive the surgery.