Messing around with chemistry and such, would sometimes be nice to be able
to fabricate with the glass tubes. I can bend them easy enough with just
the alcohol lamp, propane torch does even better.

I can make a poor man's condenser using a small diameter tubing for the
vapor and a larger tube for the water cooling jacket, rubber stoppers at
each end of the larger jacket tube, 2 holes in each stopper, one hole for
the vapor tube that passes through and another tube on each end for cooling
water inlet and outlet.

This could be done neater if I could weld glass nipples onto the cooling
jacket, and neck down each end of the cooling jacket and weld to the tube
that runs inside. I've been playing with the glass with a propane plumbing
torch, seems difficult to work. When trying to weld, too large of an area
of glass gets too soft, I think I need a flame that is more concentrated,
heating to melting temp right at the joint but not so much to the
surrounding glass.

Anyone here tried working with borosilicate glass with metalworking welding
torches? I don't see why it wouldn't do what I want (joining glass) but I
don't have the tanks anymore. I don't mind getting the tanks, but I would
like for it to work before I lease tanks and buy oxygen & acetylene (or
propane). When I had tanks, I had them for several years and hadn't used
half of my gasses up yet, that's why I took them back, I was paying monthly
rental on something I hardly ever used.

RogerN

"RogerN" wrote in message
...

Messing around with chemistry and such, would sometimes be nice to be able
to fabricate with the glass tubes. I can bend them easy enough with just
the alcohol lamp, propane torch does even better.

I can make a poor man's condenser using a small diameter tubing for the
vapor and a larger tube for the water cooling jacket, rubber stoppers at
each end of the larger jacket tube, 2 holes in each stopper, one hole for
the vapor tube that passes through and another tube on each end for
cooling water inlet and outlet.

This could be done neater if I could weld glass nipples onto the cooling
jacket, and neck down each end of the cooling jacket and weld to the tube
that runs inside. I've been playing with the glass with a propane
plumbing torch, seems difficult to work. When trying to weld, too large
of an area of glass gets too soft, I think I need a flame that is more
concentrated, heating to melting temp right at the joint but not so much
to the surrounding glass.

Anyone here tried working with borosilicate glass with metalworking
welding torches? I don't see why it wouldn't do what I want (joining
glass) but I don't have the tanks anymore. I don't mind getting the
tanks, but I would like for it to work before I lease tanks and buy oxygen
& acetylene (or propane). When I had tanks, I had them for several years
and hadn't used half of my gasses up yet, that's why I took them back, I
was paying monthly rental on something I hardly ever used.

RogerN



You might want to check this out. If you are making large glass apparatus
that you do not want to break easily, you will also need an annealing kiln.
http://www.ilpi.com/glassblowing/index.html

"anorton" wrote in message
m...


You might want to check this out. If you are making large glass apparatus
that you do not want to break easily, you will also need an annealing kiln.
http://www.ilpi.com/glassblowing/index.html

Several years ago I "won" a lot of 11 Fuji digital temperature controllers
on eBay. They have ramping programming capability, set a temperature, a
ramp time and a soak time. I thought I could use an old ceramic kiln and
one of my controllers, set to ramp down over 12 hours or whatever is
recommended. I thought of using that kind of setup for annealing hardened
steel, the ramp has 4 steps that can have ramp times up to something like 99
hours & 59 minutes.

I've also saw some info on flame annealing with the torch, if that would
work OK, I could do that temporarily and kiln anneal a batch at a time with
gentle ramp up, soak & ramp down.

For now, I have some 12" pieces of small tubing and a 12" piece of larger
tubing. If I can join 2 piece of small tubing to get over over 12", I want
to use the glass and stoppers to make a water cooled condenser. It would be
nicer if I could attach nipples to the large glass and just use single hole
stoppers. Of course if I would ever get the skills I could construct the
condenser without using stoppers at all, but I don't have the equipment or
skills for something like that now.

RogerN

For simple tubing joints with small tubing you can just warm the whole area
up to a little below the softening point, turn off the oxygen and soot up
the joint for a little insulation then let it cool in air. For bigger
things you get the final joint done and get it into the oven while it is
still very hot - if you let it cool to room temp you run the real risk of it
fracturing as it cools. Turn the oven on and get it up to temp
ballistically, an hour or two for the big oven in the glass shop at UCR,
hold at the annealing temp so the heat can soak in and everything can get
equilibrated, then cool to room temp over 8-15 hours. Annealing temp
depends on the glass type.

-----
Regards,
Carl Ijames
"RogerN" wrote in message
...

"anorton" wrote in message
m...


You might want to check this out. If you are making large glass apparatus
that you do not want to break easily, you will also need an annealing kiln.
http://www.ilpi.com/glassblowing/index.html

Several years ago I "won" a lot of 11 Fuji digital temperature controllers
on eBay. They have ramping programming capability, set a temperature, a
ramp time and a soak time. I thought I could use an old ceramic kiln and
one of my controllers, set to ramp down over 12 hours or whatever is
recommended. I thought of using that kind of setup for annealing hardened
steel, the ramp has 4 steps that can have ramp times up to something like 99
hours & 59 minutes.

I've also saw some info on flame annealing with the torch, if that would
work OK, I could do that temporarily and kiln anneal a batch at a time with
gentle ramp up, soak & ramp down.

For now, I have some 12" pieces of small tubing and a 12" piece of larger
tubing. If I can join 2 piece of small tubing to get over over 12", I want
to use the glass and stoppers to make a water cooled condenser. It would be
nicer if I could attach nipples to the large glass and just use single hole
stoppers. Of course if I would ever get the skills I could construct the
condenser without using stoppers at all, but I don't have the equipment or
skills for something like that now.

RogerN

"RogerN" wrote in message
...

Messing around with chemistry and such, would sometimes be nice to
be able to fabricate with the glass tubes. I can bend them easy
enough with just the alcohol lamp, propane torch does even better.

I can make a poor man's condenser using a small diameter tubing for
the vapor and a larger tube for the water cooling jacket, rubber
stoppers at each end of the larger jacket tube, 2 holes in each
stopper, one hole for the vapor tube that passes through and another
tube on each end for cooling water inlet and outlet.

This could be done neater if I could weld glass nipples onto the
cooling jacket, and neck down each end of the cooling jacket and
weld to the tube that runs inside. I've been playing with the glass
with a propane plumbing torch, seems difficult to work. When trying
to weld, too large of an area of glass gets too soft, I think I need
a flame that is more concentrated, heating to melting temp right at
the joint but not so much to the surrounding glass.

Anyone here tried working with borosilicate glass with metalworking
welding torches? I don't see why it wouldn't do what I want
(joining glass) but I don't have the tanks anymore. I don't mind
getting the tanks, but I would like for it to work before I lease
tanks and buy oxygen & acetylene (or propane). When I had tanks, I
had them for several years and hadn't used half of my gasses up yet,
that's why I took them back, I was paying monthly rental on
something I hardly ever used.

RogerN

Here are three results from Gutenberg:
http://www.gutenberg.org/ebooks/sear...+glass-blowing

IIRC in chemistry class we used natural gas to practice on soda-lime
glass. I never tried borosilicate, but I made miniature glass animals
in the dorm room with a candle flame and blowpipe, using the readily
available fragments of broken bottles, light bulbs and globes etc. The
milk glass globes in the bathroom turned mottled brown like the back
of a fawn if overheated with excess air.

It does take a lot of practice to get the hang of how hot glass
behaves, and wouldn't hurt to have someone show you the tricks which
are hard to describe in print.

Be SURE to anneal the piece so it doesn't shatter from locked-in
thermal stresses.

Don't apologize for the rubber-stopper condenser, it avoids the
problem of differential thermal expansion.

jsw

As others have said, you will need an annealing oven. We used natural
gas-oxygen in the glassblowing class I took many moons ago. Acetylene air
might be ok, but acetylene oxygen is way to hot. You need a small torch
with a fine tip, as I recall the inner blue cone was about 1/8" diameter at
the base and about 1/4" long when working borosilicate glass in the 6-15 mm
OD range. A glass lathe is really nice to have when doing ring seals on
condensers. Of course we had to learn to do it freehand before we got to
use the lathe since it made it so much easier :-). You can learn by
yourself from books but this is one case where access to a real glass shop
would be invaluable. See if any local junior colleges or other schools have
a class you can take. Even if they don't, go meet the instructor and bribe
him into doing some demos and letting you use his torch and oven :-).

-----
Regards,
Carl Ijames
"RogerN" wrote in message
...


Messing around with chemistry and such, would sometimes be nice to be able
to fabricate with the glass tubes. I can bend them easy enough with just
the alcohol lamp, propane torch does even better.

I can make a poor man's condenser using a small diameter tubing for the
vapor and a larger tube for the water cooling jacket, rubber stoppers at
each end of the larger jacket tube, 2 holes in each stopper, one hole for
the vapor tube that passes through and another tube on each end for cooling
water inlet and outlet.

This could be done neater if I could weld glass nipples onto the cooling
jacket, and neck down each end of the cooling jacket and weld to the tube
that runs inside. I've been playing with the glass with a propane plumbing
torch, seems difficult to work. When trying to weld, too large of an area
of glass gets too soft, I think I need a flame that is more concentrated,
heating to melting temp right at the joint but not so much to the
surrounding glass.

Anyone here tried working with borosilicate glass with metalworking welding
torches? I don't see why it wouldn't do what I want (joining glass) but I
don't have the tanks anymore. I don't mind getting the tanks, but I would
like for it to work before I lease tanks and buy oxygen & acetylene (or
propane). When I had tanks, I had them for several years and hadn't used
half of my gasses up yet, that's why I took them back, I was paying monthly
rental on something I hardly ever used.

RogerN

On Aug 29, 4:07*pm, "RogerN" wrote:
Messing around with chemistry and such, would sometimes be nice to be able
to fabricate with the glass tubes. *I can bend them easy enough with just
the alcohol lamp, propane torch does even better.

I can make a poor man's condenser using a small diameter tubing for the
vapor and a larger tube for the water cooling jacket, rubber stoppers at
each end of the larger jacket tube, 2 holes in each stopper, one hole for
the vapor tube that passes through and another tube on each end for cooling
water inlet and outlet.

This could be done neater if I could weld glass nipples onto the cooling
jacket, and neck down each end of the cooling jacket and weld to the tube
that runs inside. *I've been playing with the glass with a propane plumbing
torch, seems difficult to work. *When trying to weld, too large of an area
of glass gets too soft, I think I need a flame that is more concentrated,
heating to melting temp right at the joint but not so much to the
surrounding glass.

Anyone here tried working with borosilicate glass with metalworking welding
torches? *I don't see why it wouldn't do what I want (joining glass) but I
don't have the tanks anymore. *I don't mind getting the tanks, but I would
like for it to work before I lease tanks and buy oxygen & acetylene (or
propane). * When I had tanks, I had them for several years and hadn't used
half of my gasses up yet, that's why I took them back, I was paying monthly
rental on something I hardly ever used.

RogerN

I did it many moons ago as part of a chemistry course. Natural gas
was the fuel, the torch was more than just a bunsen burner. Pyrex
behaves differently than soda lime, you have to stay with it all the
time or it sags and then freezes, not much time between soft and then
hard. There are several books you can get out there on lab
glassblowing, some are on archive.org. It's one of those things that
it's hard to pick up from a book, you'll have a lot of failures until
you get the skills. For some things, you need a cross-fire torch
array, not exactly a common-place thing. The annealing kiln is a must
for anything but small tubing joints. You can use crossed polarizers
to see the strains in your joints.

Stan

On Friday, August 31, 2012 10:29:41 AM UTC-10, Stanley Schaefer wrote:
On Aug 29, 4:07*pm, "RogerN" wrote:

Messing around with chemistry and such, would sometimes be nice to be able

to fabricate with the glass tubes. *I can bend them easy enough with just

the alcohol lamp, propane torch does even better.



I can make a poor man's condenser using a small diameter tubing for the

vapor and a larger tube for the water cooling jacket, rubber stoppers at

each end of the larger jacket tube, 2 holes in each stopper, one hole for

the vapor tube that passes through and another tube on each end for cooling

water inlet and outlet.



This could be done neater if I could weld glass nipples onto the cooling

jacket, and neck down each end of the cooling jacket and weld to the tube

that runs inside. *I've been playing with the glass with a propane plumbing

torch, seems difficult to work. *When trying to weld, too large of an area

of glass gets too soft, I think I need a flame that is more concentrated,

heating to melting temp right at the joint but not so much to the

surrounding glass.



Anyone here tried working with borosilicate glass with metalworking welding

torches? *I don't see why it wouldn't do what I want (joining glass) but I

don't have the tanks anymore. *I don't mind getting the tanks, but I would

like for it to work before I lease tanks and buy oxygen & acetylene (or

propane). * When I had tanks, I had them for several years and hadn't used

half of my gasses up yet, that's why I took them back, I was paying monthly

rental on something I hardly ever used.



RogerN



I did it many moons ago as part of a chemistry course. Natural gas

was the fuel, the torch was more than just a bunsen burner. Pyrex

behaves differently than soda lime, you have to stay with it all the

time or it sags and then freezes, not much time between soft and then

hard. There are several books you can get out there on lab

glassblowing, some are on archive.org. It's one of those things that

it's hard to pick up from a book, you'll have a lot of failures until

you get the skills. For some things, you need a cross-fire torch

array, not exactly a common-place thing. The annealing kiln is a must

for anything but small tubing joints. You can use crossed polarizers

to see the strains in your joints.



Stan

You can make a torch out of 1/2" copper pipe T with an end cap with a hole drilled in it. Make an eye dropper shape out of glass tube and put it through a cork and stick it in the other end of the T. Gas goes through the glass tube pointed at the hole in the copper end cap. O2 or air goes through the bottom of the T and out the hole in the end cap. Adjust gas and air so it burns clean.
Karl

wrote in message
...

On Friday, August 31, 2012 10:29:41 AM UTC-10, Stanley Schaefer wrote:
snip

You can make a torch out of 1/2" copper pipe T with an end cap with a hole
drilled in it. Make an eye dropper shape out of glass tube and put it
through a cork and stick it in the other end of the T. Gas goes through the
glass tube pointed at the hole in the copper end cap. O2 or air goes
through the bottom of the T and out the hole in the end cap. Adjust gas and
air so it burns clean.
Karl


I found a few old free glassblowing books in PDF files, they show the type
of torch you describe, looks like back in that day people made more of their
own stuff, hence the glassblowing for their own lab glassware. The old
books show they used air in the center and fuel gas on the outside.

As shown on page 10 of this manual (page 12 of PDF file).
http://ia701204.us.archive.org/23/it...assblowing.pdf
Also on page 4 he (page 16 of PDF file)
http://ia700308.us.archive.org/15/it...00shenrich.pdf
Also on page 3 he (page 15 of PDF file) This one uses adjusting screws
for centering
http://ia600208.us.archive.org/4/ite...02bolarich.pdf

Other books of interest:
This is a huge book, over 1500 pages, chapter 2 has lab glass info but the
book also goes into lab metalworking, etc.
http://ia600706.us.archive.org/21/it...ryHandbook.pdf

http://ia700400.us.archive.org/16/it...00shenuoft.pdf
http://ia700400.us.archive.org/2/ite...00frarrich.pdf

Gilbert used to have a glass blowing kit
http://ia700209.us.archive.org/22/it...glas00lynd.pdf

RogerN

Thanks for correcting that. A glass blower chemist demoed and taught us that in high school about 40 years ago.
Karl


On Saturday, September 1, 2012 4:54:00 PM UTC-10, RogerN wrote:
wrote in message
...



On Friday, August 31, 2012 10:29:41 AM UTC-10, Stanley Schaefer wrote:

snip



You can make a torch out of 1/2" copper pipe T with an end cap with a hole

drilled in it. Make an eye dropper shape out of glass tube and put it

through a cork and stick it in the other end of the T. Gas goes through the

glass tube pointed at the hole in the copper end cap. O2 or air goes

through the bottom of the T and out the hole in the end cap. Adjust gas and

air so it burns clean.

Karl





I found a few old free glassblowing books in PDF files, they show the type

of torch you describe, looks like back in that day people made more of their

own stuff, hence the glassblowing for their own lab glassware. The old

books show they used air in the center and fuel gas on the outside.



As shown on page 10 of this manual (page 12 of PDF file).

http://ia701204.us.archive.org/23/it...assblowing.pdf

Also on page 4 he (page 16 of PDF file)

http://ia700308.us.archive.org/15/it...00shenrich.pdf

Also on page 3 he (page 15 of PDF file) This one uses adjusting screws

for centering

http://ia600208.us.archive.org/4/ite...02bolarich.pdf



Other books of interest:

This is a huge book, over 1500 pages, chapter 2 has lab glass info but the

book also goes into lab metalworking, etc.

http://ia600706.us.archive.org/21/it...ryHandbook.pdf



http://ia700400.us.archive.org/16/it...00shenuoft.pdf

http://ia700400.us.archive.org/2/ite...00frarrich.pdf



Gilbert used to have a glass blowing kit

http://ia700209.us.archive.org/22/it...glas00lynd.pdf



RogerN

On 9/1/2012 22:53, RogerN wrote:
wrote in message
...

On Friday, August 31, 2012 10:29:41 AM UTC-10, Stanley Schaefer wrote:
snip

You can make a torch out of 1/2" copper pipe T with an end cap with a hole
drilled in it. Make an eye dropper shape out of glass tube and put it
through a cork and stick it in the other end of the T. Gas goes through the
glass tube pointed at the hole in the copper end cap. O2 or air goes
through the bottom of the T and out the hole in the end cap. Adjust gas and
air so it burns clean.
Karl


I found a few old free glassblowing books in PDF files, they show the type
of torch you describe, looks like back in that day people made more of their
own stuff, hence the glassblowing for their own lab glassware. The old
books show they used air in the center and fuel gas on the outside.

As shown on page 10 of this manual (page 12 of PDF file).
http://ia701204.us.archive.org/23/it...assblowing.pdf
Also on page 4 he (page 16 of PDF file)
http://ia700308.us.archive.org/15/it...00shenrich.pdf
Also on page 3 he (page 15 of PDF file) This one uses adjusting screws
for centering
http://ia600208.us.archive.org/4/ite...02bolarich.pdf

Other books of interest:
This is a huge book, over 1500 pages, chapter 2 has lab glass info but the
book also goes into lab metalworking, etc.
http://ia600706.us.archive.org/21/it...ryHandbook.pdf

http://ia700400.us.archive.org/16/it...00shenuoft.pdf
http://ia700400.us.archive.org/2/ite...00frarrich.pdf

Gilbert used to have a glass blowing kit
http://ia700209.us.archive.org/22/it...glas00lynd.pdf

RogerN



Cool. Is there a search engine for this archive?


--
Steve Walker
(remove brain when replying)

"Steve Walker" wrote in message
...

On 9/1/2012 22:53, RogerN wrote:
snip
Gilbert used to have a glass blowing kit
http://ia700209.us.archive.org/22/it...glas00lynd.pdf

RogerN



Cool. Is there a search engine for this archive?


--
Steve Walker
(remove brain when replying)

Stanley Schaefer mentioned archive.org, I went their and searched. I had
already found most of the books in various places, but it was nice to get
several in one place.

RogerN