Sciencemadness Discussion Board

Heat bendable glass tubes

IndependentBoffin - 20-4-2011 at 16:10

When I was much younger my chemistry sets came with glass tubes for connecting into rubber stoppers with holes, etc. that could be melted above a spirit burner and bent. This allowed you to start with straight tubes and get L, C, Z, etc. shapes.

I can't seem to find these glass tubes anymore, or maybe I am not using the right search term.

Can anyone suggest where I might find them?

Lambda-Eyde - 20-4-2011 at 16:30

"Glass tubing" ?

With a bunsen burner, you can bend borosilicate as well as soda-lime tubing.

bob800 - 20-4-2011 at 16:44

A google/eBay search for "Glass Tubing" as suggested by Lambda-Eyde will give you dozens of sources. For connecting to rubber stoppers, you most likely want 5mm soda lime tubing (it's easier to melt).

For cutting tubes, you'll want a triangle file to score them. This is also readily available if you do a quick search.

watson.fawkes - 20-4-2011 at 17:58

The term of art used in trade is "flint glass tubing". Google brings up plenty of vendors with this search.

Sedit - 20-4-2011 at 18:15

I could possibly sell some, im getting into glass blowing and working and I am going to pick up some supplies tommorow. I normally get Boro but Sodalime is an option.

Bot0nist - 20-4-2011 at 18:57

I go through a lot of these. If your creative you can rig up some nice DIY rigs with them, and there inexpensive. <a href="http://unitednuclear.com/index.php?main_page=product_info&cPath=25_26&products_id=301">Glass Tubing.</a>

IndependentBoffin - 20-4-2011 at 22:33

Quote: Originally posted by bob800  
A google/eBay search for "Glass Tubing" as suggested by Lambda-Eyde will give you dozens of sources. For connecting to rubber stoppers, you most likely want 5mm soda lime tubing (it's easier to melt).

For cutting tubes, you'll want a triangle file to score them. This is also readily available if you do a quick search.


Thanks guys I remembered looking on Ebay but noted that all the glass tubing on Ebay comes from one US seller.

Let's hope he stays in business for a long time!

Local UK business suppliers are selling these at rip off prices. E.g. http://www.coleparmer.co.uk/catalog/product_view.asp?sku=347...

8mm OD, 6mm ID, 1890mm long glass tubing £248 + 20% tax. Makes you wonder if it comes in a gold plated box.

Is PTFE tubing an adequate substitute for glass tubing? In the near future I will be distilling acetic anhydride at 140C and also making white fuming nitric acid.

[Edited on 21-4-2011 by IndependentBoffin]

bbartlog - 21-4-2011 at 06:09

Depending on how much you plan to use you might want to track down a wholesale supplier. I got annoyed with the markup on little bits of tubing available on ebay and elsewhere, and ordered a box containing 250 pieces of 4' long 6mm OD borosilicate glass (Corning) for a little over a hundred dollars (but I forget where... would have to run look at the box it shipped in, which I still have).
As to whether it would melt over a spirit burner though, not sure. I use a bunsen burner.

watson.fawkes - 21-4-2011 at 14:04

Quote: Originally posted by IndependentBoffin  
Local UK business suppliers are selling these at rip off prices. E.g. http://www.coleparmer.co.uk/catalog/product_view.asp?sku=347...

8mm OD, 6mm ID, 1890mm long glass tubing £248 + 20% tax. Makes you wonder if it comes in a gold plated box.
That's 189 pieces per case and the price is per case. It's still around double what you'd pay for the same thing from a dedicated glass supplier. Standard lengths are 48 inches in the US and (IIRC) 1500 mm elsewhere.

symboom - 1-3-2017 at 02:38

Can flint glass handle thermal shock better than soda lime glass
I cant find anything on this
If I remember right themal different within borosilicate is 200f
And soda lime is 90f where can I find the properties of this glass

Flint glass compared to soda lime glass

battoussai114 - 1-3-2017 at 06:08

Quote: Originally posted by symboom  
Can flint glass handle thermal shock better than soda lime glass
I cant find anything on this
If I remember right themal different within borosilicate is 200f
And soda lime is 90f where can I find the properties of this glass

Flint glass compared to soda lime glass


This nist paper has the linear coefficient of expansion of some glasses. While I had the biggests brain fart interpreting the table but it still is at least a piece of info on the material.

[Edited on 1-3-2017 by battoussai114]

highpower48 - 1-3-2017 at 10:02

For a US retailer in small quantities try Home Science Tools

Dr.Bob - 1-3-2017 at 10:41

Flint or soda glass does NOT handle thermal stress well, that is why most labware is borosilicate, as it has a far smaller thermal expansion coefficient. But for many uses, cheap soda glass is fine, like small pieces of tubing.

If anyone is looking for borosilicate glass tubing, I have a few pieces in several diameters, and could cut them into more easily shipable lengths. I would only ask about $1 per 4' piece, but I am happy to sell small amounts, as long as I can cut them into smaller pieces, as finding 4' shipping tubes is a pain.