drill old gass
 

On 03/13/2011 12:24 PM, Karl Townsend wrote:

I haven't measured up for sure, but I'm thinking this stuff is 1/8 NPT size.

Lamps and stuff use 1/8" NPS rather than NPT. I was told that is a
carry-over from the gas plumbing that it replaced.

BobH

drill old gass
 

Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

drill old gass
 

Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

The old way would be to use some copper or brass tube with an OD the
size of the hole you want. Make a dam round the hole with plasticene and
add some abrasive like valve grinding paste and a bit of water or oil,
Hold the tube in a drill press running at a slow speed and repeatadly
apply pressure and lift. The abrasive imbeds in the softer tube material
like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still have the dam to
retain water to keep the glass cool. You can probably buy them on eBay
for a few dollars in the size you want.

drill old gass
 

On Sun, 13 Mar 2011 12:48:39 +0000, David Billington
wrote:

Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

The old way would be to use some copper or brass tube with an OD the
size of the hole you want. Make a dam round the hole with plasticene and
add some abrasive like valve grinding paste and a bit of water or oil,
Hold the tube in a drill press running at a slow speed and repeatadly
apply pressure and lift. The abrasive imbeds in the softer tube material
like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still have the dam to
retain water to keep the glass cool. You can probably buy them on eBay
for a few dollars in the size you want.

Carbide bits are available for under ten bucks and they work extremely
well for tile, glass (not tempered), and ceramics. No cooling
necessary at all. http://tinyurl.com/48c32js HF apparently doesn't
carry them any more.

Back up the drilling point so the glass doesn't break out the back
side. Cold clay works well to provide a solid backing. Use a light
touch and immediately stop the drill upon exiting. Quick-stopping
cordless drill motors work best for this.

--
You create your opportunities by asking for them.
-- Patty Hansen

drill old gass
 

Larry Jaques wrote:
On Sun, 13 Mar 2011 12:48:39 +0000, David Billington
wrote:


Karl Townsend wrote:

Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl


The old way would be to use some copper or brass tube with an OD the
size of the hole you want. Make a dam round the hole with plasticene and
add some abrasive like valve grinding paste and a bit of water or oil,
Hold the tube in a drill press running at a slow speed and repeatadly
apply pressure and lift. The abrasive imbeds in the softer tube material
like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still have the dam to
retain water to keep the glass cool. You can probably buy them on eBay
for a few dollars in the size you want.


Carbide bits are available for under ten bucks and they work extremely
well for tile, glass (not tempered), and ceramics. No cooling
necessary at all. http://tinyurl.com/48c32js HF apparently doesn't
carry them any more.

Back up the drilling point so the glass doesn't break out the back
side. Cold clay works well to provide a solid backing. Use a light
touch and immediately stop the drill upon exiting. Quick-stopping
cordless drill motors work best for this.

--
You create your opportunities by asking for them.
-- Patty Hansen

Cooling may not be required but it does help prevent the glass cracking
due to thermally induced stress.

drill old gass
 

"Larry Jaques" wrote in message
No cooling
necessary at all. http://tinyurl.com/48c32js HF apparently doesn't
carry them any more.

Or a lot of other things either.

drill old gass
 

David Billington Inscribed thus:

Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small
lights inside and needs a hole drilled. I haven't measured up for
sure, but I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

The old way would be to use some copper or brass tube with an OD the
size of the hole you want. Make a dam round the hole with plasticene
and add some abrasive like valve grinding paste and a bit of water or
oil, Hold the tube in a drill press running at a slow speed and
repeatadly apply pressure and lift. The abrasive imbeds in the softer
tube material like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still have the dam
to retain water to keep the glass cool. You can probably buy them on
eBay for a few dollars in the size you want.

Agreed ! Diamond Drills on Ebay have a good selection that are
inexpensive.

--
Best Regards:
Baron.

drill old gass
 

On Sun, 13 Mar 2011 15:55:57 +0000, David Billington
wrote:

Larry Jaques wrote:
On Sun, 13 Mar 2011 12:48:39 +0000, David Billington
wrote:


Karl Townsend wrote:

The new way would be to use a diamond hole saw but still have the dam to
retain water to keep the glass cool. You can probably buy them on eBay
for a few dollars in the size you want.


Carbide bits are available for under ten bucks and they work extremely
well for tile, glass (not tempered), and ceramics. No cooling
necessary at all. http://tinyurl.com/48c32js HF apparently doesn't
carry them any more.

Back up the drilling point so the glass doesn't break out the back
side. Cold clay works well to provide a solid backing. Use a light
touch and immediately stop the drill upon exiting. Quick-stopping
cordless drill motors work best for this.

Cooling may not be required but it does help prevent the glass cracking
due to thermally induced stress.

I haven't noticed warmth above body temp in drillings I've done with
the carbide "spade" style drills I use. I know the powdered diamond
style gets hotter and can require coolant.

--
You create your opportunities by asking for them.
-- Patty Hansen

drill old gass
 

On Sun, 13 Mar 2011 09:44:07 -0700, "Bob La Londe"
wrote:

"Larry Jaques" wrote in message
No cooling
necessary at all. http://tinyurl.com/48c32js HF apparently doesn't
carry them any more.

Or a lot of other things either.

That's why I like to buy lots of little things when they show up
there.

--
You create your opportunities by asking for them.
-- Patty Hansen

drill old gass
 

Thanks for the advice. I placed an order with an eBay vendor.

drill old gass
 

Larry Jaques wrote:

Carbide bits are available ... http://tinyurl.com/48c32js ...

Ooo ... they have "Integrated Speed Load system". What??? ... how can a
drill bit have an "Integrated Speed Load system"? And what is it, for
that matter. Oh, I know ... it's a triumph of marketing over engineering.

Bob

drill old gass
 

Karl Townsend wrote:
Thanks for the advice. I placed an order with an eBay vendor.

What did you go for in the end?.

BTW never used the spade bits myself but IIRC they've been around for
decades or more, at least as long as I can recall but maybe the
materials have improved.

drill old gass
 

Many of the quick-change drill accessory "speed chucks" utilize the groove
around the hex portion of the shank to allow fast tool/cutter changes.
These types of "speed chucks" typically have an outer sleeve that's pulled
back to release a ball or other latching device which allows the user to
change the tool/cutters quickly, instead of loosening the drill's chuck, and
then retightening it for each change of tool/cutter.

--
WB
..........


"Bob Engelhardt" wrote in message
...
Larry Jaques wrote:

Carbide bits are available ... http://tinyurl.com/48c32js ...

Ooo ... they have "Integrated Speed Load system". What??? ... how can a
drill bit have an "Integrated Speed Load system"? And what is it, for
that matter. Oh, I know ... it's a triumph of marketing over engineering.

Bob

drill old gass
 

Karl Townsend wrote:

Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

I still like the brass tube and abrasive powder method. If you take it slow, stresses are
much lower than some pointy hard thing.

Industrial diamond paste sounds like something that might hold promise.

Wes

drill old gass
 

"Larry Jaques" wrote in
message ...
On Sun, 13 Mar 2011 12:48:39 +0000, David Billington
wrote:

Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that
often.

She has old canning jars. The type with a glass lid and
a little wire
arrangement to pull the glass lid tight. She wants to
put small lights
inside and needs a hole drilled. I haven't measured up
for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points
off for every
one I break.

Karl

The old way would be to use some copper or brass tube with
an OD the
size of the hole you want. Make a dam round the hole with
plasticene and
add some abrasive like valve grinding paste and a bit of
water or oil,
Hold the tube in a drill press running at a slow speed and
repeatadly
apply pressure and lift. The abrasive imbeds in the softer
tube material
like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still
have the dam to
retain water to keep the glass cool. You can probably buy
them on eBay
for a few dollars in the size you want.

Carbide bits are available for under ten bucks and they
work extremely
well for tile, glass (not tempered), and ceramics. No
cooling
necessary at all. http://tinyurl.com/48c32js HF
apparently doesn't
carry them any more.

Back up the drilling point so the glass doesn't break out
the back
side. Cold clay works well to provide a solid backing. Use
a light
touch and immediately stop the drill upon exiting.
Quick-stopping
cordless drill motors work best for this.


I haven't drilled that species of old glass but certain of
the antique
compositions like to fragment around the periphery of
hole ends with carbide.

Diamond hole drills would be my option. The tricks are to
put them in a pond of water, feed straight, lightly and
slowly
and back the exit hole up with something for support
against
rim breakouts.

If you have any waterproof ring (e.g. big gasket, O ring)
you
can use that as your coolant reservoir after using grease to
affix it to the glass.

I use a modified, quick-setting plaster as breakout
protection
on because it can conform to the glass. It shears
off after drilling with a tiny bit of cleanup. Something
that
didn't involve cleanup would be an improvement.

Regards,

Edward Hennessey


--
You create your opportunities by asking for them.
-- Patty Hansen

drill old gass
 

"Karl Townsend" wrote in message
...
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

I've found that diamond grinding burrs in a Dremel do the job very
well. Submerging the glass under water with the grinding site just
beneath the surface catches the dust, keeps everything cool, and
damps vibrations in the glass.
Art

drill old gass
 

On Sun, 13 Mar 2011 17:20:32 -0400, Bob Engelhardt
wrote:

Larry Jaques wrote:

Carbide bits are available ... http://tinyurl.com/48c32js ...

Ooo ... they have "Integrated Speed Load system". What??? ... how can a
drill bit have an "Integrated Speed Load system"? And what is it, for
that matter. Oh, I know ... it's a triumph of marketing over engineering.

That's marketspeak for "quick-change chuck style", Bob.
I call 'em "hex-shanked do-dads", myself.

--
You create your opportunities by asking for them.
-- Patty Hansen

drill old gass
 

On Sun, 13 Mar 2011 19:21:20 -0400, Wes
wrote:

Karl Townsend wrote:

Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

I still like the brass tube and abrasive powder method. If you take it slow, stresses are
much lower than some pointy hard thing.

Industrial diamond paste sounds like something that might hold promise.

It also costs an arm and a leg and takes a week per hole. Pass.
The arrowhead carbides are dynamite, Wes. Try it. You'll like it.

--
You create your opportunities by asking for them.
-- Patty Hansen

drill old gass
 

On Sun, 13 Mar 2011 12:48:39 +0000, David Billington
wrote:

Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

The old way would be to use some copper or brass tube with an OD the
size of the hole you want. Make a dam round the hole with plasticene and
add some abrasive like valve grinding paste and a bit of water or oil,
Hold the tube in a drill press running at a slow speed and repeatadly
apply pressure and lift. The abrasive imbeds in the softer tube material
like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still have the dam to
retain water to keep the glass cool. You can probably buy them on eBay
for a few dollars in the size you want.
I used a cordless screwdriver powering a copper or brass tube through
a 1/4" square drive U joint and very little pressure.
Gerry :-)}
London, Canada

drill old gass
 

On 03/13/2011 05:24 AM, Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

Whatever else you do, experiment on coke bottles or mayonnaise jars or
whatever new glass things you have sitting around, before you go
thumping on SWMBO's nice old antique stuff.

Instead of putting light bulbs in there, wouldn't they look better with
canned apple slices, or cherries, or something?

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html

drill old gass
 

Larry Jaques wrote:
Bob Engelhard wrote:

Larry Jaques wrote:
Carbide bits are available ... http://tinyurl.com/48c32js ...

Ooo ... they have "Integrated Speed Load system". What??? ... how can a
drill bit have an "Integrated Speed Load system"? And what is it, for
that matter. Oh, I know ... it's a triumph of marketing over engineering.


That's marketspeak for "quick-change chuck style", Bob.
I call 'em "hex-shanked do-dads", myself.

Oh ... reading comprehension problem. I read "Integrated Speed Load
system" as something integral to the bit that had to do with the load on
the bit & bit speed! I should pay better attention.

Bob

drill old gass
 

responding to
http://www.rittercnc.com/metalworkin...ss-494625-.htm
bitsinbobs wrote:

Larry Jaques wrote:

On Sun, 13 Mar 2011 12:48:39 +0000, David Billington
wrote:

Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a
little wire
arrangement to pull the glass lid tight. She wants to put
small lights
inside and needs a hole drilled. I haven't measured up for
sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off
for every
one I break.

Karl

The old way would be to use some copper or brass tube with an OD
the
size of the hole you want. Make a dam round the hole with
plasticene and
add some abrasive like valve grinding paste and a bit of water or
oil,
Hold the tube in a drill press running at a slow speed and
repeatadly
apply pressure and lift. The abrasive imbeds in the softer tube
material
like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still have the
dam to
retain water to keep the glass cool. You can probably buy them on
eBay
for a few dollars in the size you want.

Carbide bits are available for under ten bucks and they work extremely
well for tile, glass (not tempered), and ceramics. No cooling
necessary at all. http://tinyurl.com/48c32js HF apparently doesn't
carry them any more.

Back up the drilling point so the glass doesn't break out the back
side. Cold clay works well to provide a solid backing. Use a light
touch and immediately stop the drill upon exiting. Quick-stopping
cordless drill motors work best for this.

--
You create your opportunities by asking for them.
-- Patty Hansen


--I agree with Larry , heat is not the problem , vibration is , drilled a
car window once , great job , standing talking 5 mins later booooof
shattered , use a hand brace
IF IT'S NOT BROKE WORK AT IT UNTIL IT IS

drill old gass
 

On Sun, 13 Mar 2011 17:51:41 -0700, Larry Jaques
wrote:

On Sun, 13 Mar 2011 19:21:20 -0400, Wes
wrote:

Karl Townsend wrote:

Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

I still like the brass tube and abrasive powder method. If you take it slow, stresses are
much lower than some pointy hard thing.

Industrial diamond paste sounds like something that might hold promise.

It also costs an arm and a leg and takes a week per hole. Pass.
The arrowhead carbides are dynamite, Wes. Try it. You'll like it.
Valve grinding compound and a brass tube with a couple notches works
well and fairly fast.
Gerry :-)}
London, Canada

drill old gass
 

Gerald Miller wrote:
On Sun, 13 Mar 2011 17:51:41 -0700, Larry Jaques
wrote:

On Sun, 13 Mar 2011 19:21:20 -0400, Wes
wrote:

Karl wrote:

Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

I still like the brass tube and abrasive powder method. If you take it slow, stresses are
much lower than some pointy hard thing.

Industrial diamond paste sounds like something that might hold promise.

It also costs an arm and a leg and takes a week per hole. Pass.
The arrowhead carbides are dynamite, Wes. Try it. You'll like it.
Valve grinding compound and a brass tube with a couple notches works
well and fairly fast.
Gerry :-)}
London, Canada


I remember making lamps out of bottles when I was a kid. I don't
remember exactly how I made the holes but I seem to remember dropping a
ball bearing through a tube onto the bottle and the results were like a
bebe hole in a window. I do remember the way to cut the bottles in
half. Get a piece of cotton string and tie it around the bottle where
you want to cut. Soak the string in lighter fluid and light it up..
The bottle will break around where the string is.

John

drill old gass
 

On Sun, 13 Mar 2011 19:29:37 -0700, Tim Wescott
wrote:

On 03/13/2011 05:24 AM, Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled. I haven't measured up for sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off for every
one I break.

Karl

Whatever else you do, experiment on coke bottles or mayonnaise jars or
whatever new glass things you have sitting around, before you go
thumping on SWMBO's nice old antique stuff.

Good advice.

Instead of putting light bulbs in there, wouldn't they look better with
canned apple slices, or cherries, or something?

You're not married???

Karl

drill old gass
 

The 5-piece set I just bought at Ollie's (new discontinued product
surplus/salvage store) was $4.99 +tax, a Black & Decker set, although
without the hex shanks/quick change capability.

--
WB
..........


"Larry Jaques" wrote in message
...

Carbide bits are available for under ten bucks and they work extremely
well for tile, glass (not tempered), and ceramics. No cooling
necessary at all. http://tinyurl.com/48c32js HF apparently doesn't
carry them any more.

Back up the drilling point so the glass doesn't break out the back
side. Cold clay works well to provide a solid backing. Use a light
touch and immediately stop the drill upon exiting. Quick-stopping
cordless drill motors work best for this.

--
You create your opportunities by asking for them.
-- Patty Hansen

drill old gass
 

Karl Townsend wrote:
You don't understand the stakes here. I'm the one that will get the
heat treatment. Antique glass top canning jars are quite rare.

"... quite rare." In that case, don't drill at all. Make 2 capacitors
on the bottom of the jars by gluing aluminum foil on the inside &
outside. Connect the light(s) (LED's) between the capacitors on the
inside and drive the outside with a high frequency. I'll let you work
out the numbers.

Bob

Or, do like the chargers for electric toothbrushes & make core less
transformers with coils on the inside & outside of the jar. I like the
capacitors better.

drill old gass
 

On Mar 13, 9:09*pm,
(bitsinbobs) wrote:
responding tohttp://www.rittercnc.com/metalworking/drill-old-gass-494625-..htm





bitsinbobs wrote:
Larry Jaques wrote:
On Sun, 13 Mar 2011 12:48:39 +0000, David Billington
wrote:
Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a
little wire
arrangement to pull the glass lid tight. She wants to put
small lights
inside and needs a hole drilled. I haven't measured up for
sure, but
I'm thinking this stuff is 1/8 NPT size.

OK, how do I drill very old glass? I get several points off
for every
one I break.

Karl

The old way would be to use some copper or brass tube with an OD
the
size of the hole you want. Make a dam round the hole with
plasticene and
add some abrasive like valve grinding paste and a bit of water or
oil,
Hold the tube in a drill press running at a slow speed and
repeatadly
apply pressure and lift. The abrasive imbeds in the softer tube
material
like a lap and grinds through the glass.

The new way would be to use a diamond hole saw but still have the
dam to
retain water to keep the glass cool. You can probably buy them on
eBay
for a few dollars in the size you want.
Carbide bits are available for under ten bucks and they work extremely
well for tile, glass (not tempered), and ceramics. No cooling
necessary at all.http://tinyurl.com/48c32js*HF apparently doesn't
carry them any more.
Back up the drilling point so the glass doesn't break out the back
side. Cold clay works well to provide a solid backing. Use a light
touch and immediately stop the drill upon exiting. Quick-stopping
cordless drill motors work best for this.
--
You create your opportunities by asking for them.
* * * * * * * * * * * * * * * * *-- Patty Hansen

--I agree with Larry , heat is not the problem , vibration is , drilled a
car window once , great job , standing talking 5 mins later *booooof
shattered , use a hand brace *
IF IT'S NOT BROKE WORK AT IT UNTIL IT IS- Hide quoted text -

- Show quoted text -

Not vibration in that case, US car side and rear windows are tempered
glass, I'm surprised the window lasted long enough for you to drill
through it. Usually tempered glass will crumble after the tensioned
surface is scratched. Stuff is very strong, but that's its weakness.

Stan

drill old gass
 

Pete Snell wrote:
On 3/13/2011 8:48 AM, David Billington wrote:
Karl Townsend wrote:
Milady needs me for my shop skills. Don't happen that often.

She has old canning jars. The type with a glass lid and a little wire
arrangement to pull the glass lid tight. She wants to put small lights
inside and needs a hole drilled.
snip
The old way would be to use some copper or brass tube with an OD the
size of the hole you want. Make a dam round the hole with plasticene and
add some abrasive like valve grinding paste and a bit of water or oil,
Hold the tube in a drill press running at a slow speed and repeatadly
apply pressure and lift. The abrasive imbeds in the softer tube material
like a lap and grinds through the glass.

I did the exact same job a few years back, and used the technique
David describes. It works well, but you have to be patient. It was about
10 minutes of 'drilling' for each hole if I recall correctly.

FWIW, I read this exact thing some decades ago. Haven't tried it,
because I haven't had a need to drill holes in glass, but it's nice
to know it works. :-)

Cheers!
Rich