Glass tubing

magda

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Has anyone tried glass tubing? I would feel afraid of breaking it every single time.
Is it worth the investment?

Share your experiences.
 
I haven't tried it. I want to but the costs go up substantially as you'll need more right angled fittings and that sort of thing. That said, the advantage is that glass doesn't stain while the PETG and acrylic do.
 
And you also have to cut everything yourself, which makes screwing up an expensive endeavor...
 
I think it would look amazing but yeah I'd be afraid of breaking it. Plus it must be a total PITA to work with.
 
And you also have to cut everything yourself, which makes screwing up an expensive endeavor...

You'll also need an annealing oven to relieve the stress inherent in glass that is worked cold, and even annealed glass is going to have an extremely small amount of flexure tolerance compared to polymer tubing, although I would imagine you could engineer fittings to provide some degree of strain relief.
 
I have built 2 systems with glass tubing, and helped build a third. I was apprehensive at first, but it turned out to be really easy and a lot of fun.

1) Borosilicate glass tubing has thick walls and an overall small diameter. Unless you are really trying to break it, you are unlikely to do so. It's pretty tough, actually.

2) The glass tubing is actually pretty easy to cut, so long as you don't need to cut pieces shorter than about the width of your hand - more on that in a sec.

To cut: You use a glass cutter to etch what looks like a scratch on the tube - should be at least 1/3 of the way around the tube. moisten the etch with water, or even dab some saliva on it with your finger, grip the tube with your hands, thumbs meeting in the middle under the etching with the etching facing away from your thumbs and just snap. There isn't even any mess. You will most of the time get a very clean break and it does not take a lot of force -- unless that is...

About the size of the pieces: Any shorter than about the width of your hand from the end of the tube and it becomes super difficult to break the tube. You need something like a vice to hold the short end and you dramatically increase the risk of making sharp "chips" in the tube at the break that you will then need to file down. Glass is very, very hard, and filing it down sucks.

3) Measure Twice, Cut Once. And don't forget to take into account how deep the tube goes into the fitting on each end. Unlike PETG, if your piece is a little too long, you are not likely to trim it down - like I said... glass is very, very hard and filing it down sucks.

4) Glass tubing is NOT perfectly sized all the way down. If you get 12mm OD tubing, buy 13mm hard tube fittings or the tubing might not actually fit into the fitting. Learned this the hard way.

5) Pre-plan your runs, and buy 2 more tubes than you think you'll need, remembering that you are limited to perfectly straight and 90-degree angles. Oh, and yeah... unless you buy the tubes that have a baked-in 90-degree angle (and you can buy those) you are going to need 90-degree fittings for the bends.

6) Glass tubing is a LOT heavier than PETG. Long runs (especially long runs going into an angle) may need support to prevent sagging.

My experience was with Mayhem's branded glass tubing that I got a bundle of from Performance PCs. The price-per-tube was only $7 or $8 per tube, and I only needed 5 tubes for each build. Considering the cost of everything else that goes into a custom loop, the cost of the glass and the cutter (about $5 or so IIRC) were negligible.
 
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You'll also need an annealing oven to relieve the stress inherent in glass that is worked cold, and even annealed glass is going to have an extremely small amount of flexure tolerance compared to polymer tubing, although I would imagine you could engineer fittings to provide some degree of strain relief.

I have not personally encountered any need for an oven.
 
You can use a mapp gas torch. If you use pyrex wall tubing and a mapp gas torch you can bend it the same way people bend the acrylic tubing. This is on my to do list for the next time i do a water cooled build. I have done some glass work, just not combined it with a pc water cooled build...yet.
 
Very good, I defer to your experience in the field.
on the edges where the glass tubing is cut, you really should heat it slowly to a dull red and then let it cool naturally. this de-strains the fractured edge that can otherwise be a shatter point in glass. will this matter on your build? probably not unless there is stress on the tubing.
 
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If you really want to do glass custom, find a neon guy (or gal).
Neon signage is amazing and I did a fair amount in the 70s. LED signage is kind of making it go away today though.

Here's an idea of technique and tools used:

(Annoying music warning!)



Fittings should only be used at G4 terminations and a single contiguous piece of glass is what you want!
 
I have built 2 systems with glass tubing, and helped build a third. I was apprehensive at first, but it turned out to be really easy and a lot of fun.

1) Borosilicate glass tubing has thick walls and an overall small diameter. Unless you are really trying to break it, you are unlikely to do so. It's pretty tough, actually.

2) The glass tubing is actually pretty easy to cut, so long as you don't need to cut pieces shorter than about the width of your hand - more on that in a sec.

To cut: You use a glass cutter to etch what looks like a scratch on the tube - should be at least 1/3 of the way around the tube. moisten the etch with water, or even dab some saliva on it with your finger, grip the tube with your hands, thumbs meeting in the middle under the etching with the etching facing away from your thumbs and just snap. There isn't even any mess. You will most of the time get a very clean break and it does not take a lot of force -- unless that is...

About the size of the pieces: Any shorter than about the width of your hand from the end of the tube and it becomes super difficult to break the tube. You need something like a vice to hold the short end and you dramatically increase the risk of making sharp "chips" in the tube at the break that you will then need to file down. Glass is very, very hard, and filing it down sucks.

3) Measure Twice, Cut Once. And don't forget to take into account how deep the tube goes into the fitting on each end. Unlike PETG, if your piece is a little too long, you are not likely to trim it down - like I said... glass is very, very hard and filing it down sucks.

4) Glass tubing is NOT perfectly sized all the way down. If you get 12mm OD tubing, buy 13mm hard tube fittings or the tubing might not actually fit into the fitting. Learned this the hard way.

5) Pre-plan your runs, and buy 2 more tubes than you think you'll need, remembering that you are limited to perfectly straight and 90-degree angles. Oh, and yeah... unless you buy the tubes that have a baked-in 90-degree angle (and you can buy those) you are going to need 90-degree fittings for the bends.

6) Glass tubing is a LOT heavier than PETG. Long runs (especially long runs going into an angle) may need support to prevent sagging.

My experience was with Mayhem's branded glass tubing that I got a bundle of from Performance PCs. The price-per-tube was only $7 or $8 per tube, and I only needed 5 tubes for each build. Considering the cost of everything else that goes into a custom loop, the cost of the glass and the cutter (about $5 or so IIRC) were negligible.
Very good info. I thought it was very very complicated to build, and to handle.
So they use borosilicate (Pyrex) tubing, like the ones in labs.

You should make a tutorial thread, it would definitively be a sticky one 😊
 
I bought a ton of it along with a bunsen burner to experiment with. I also bought a setup to apply pressure while bending so that my tubes don't kink. I haven't actually gotten around to trying to bend it yet though as I've been too busy. If you do go with glass, buy it from a glass supplier not a pc supplier, the cost difference is enormous, on the order of 15x-25x the price. I paid $2/1500mm of tube from mountain glass compared to $7-$15/500mm from mayhems or alphacool. You can also get colored boro glass from glass suppliers if you want as well.

To bend it without kinking you plug one end of the tube with a cork and then attach a tube to the other end and blow into the tube to supply pressure so it doesn't kink.

Unfortunately a lot of the videos out there are kind of terrible. This is probably one of the better ones I've found on bending tubing. I bought a huge amount as I assume I'm going to break a lot of glass.
 
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