how do you mold a thread on a glass jar

joel · #1 2009-03-19, 7:28pm

how do you mold a thread into glass i need to know does any body make a mold to put threads on bottles and such this is driving me nuts i have a project that needs a screw on lid and no idea how to do it PLEAS HELP

Kym · #2 2009-03-19, 10:31pm

I have never heard or seen of anything like that!

If you wound a stringer on slant around the top and and put an indent in the lid on the side just below the highest level of the stringer, that should tighten. The indent should fit in the stringer gap you left. You could put a couple of shorter series of stringers on the other hand as long as they slanted.

worth a thought. Maybe you can see what I mean in the pic if it isn't too small

Mr. Smiley · #3 2009-03-20, 4:24am

They sell threaded ends for boro... not sure what coe you need. They might sell them for soft too... don't know.

shawnette · #4 2009-03-20, 5:51am

I've actually seen a tool for that, but I can't remember where it was. I think it was on TV. You could probably find it if you googled it.

MelanieG · #5 2009-03-20, 8:12am

I posted in this thread this morning, asking if a particular way of doing something might work, but I guess my question and my idea were both so stupid that someone felt like it would be better if my post was deleted. Thanks for that.

Mr. Smiley · #6 2009-03-20, 8:14am

Quote:

Originally Posted by Oenone

I posted in this thread this morning, asking if a particular way of doing something might work, but I guess my question and my idea were both so stupid that someone felt like it would be better if my post was deleted. Thanks for that.

http://www.lampworketc.com/forums/sh...d.php?t=125100

Um no, this thread was started in two different places... your post is in the other thread. Nobody deleted anything.

MelanieG · #7 2009-03-20, 8:18am

I never even thought to check that!

In any case, I hope that you figure out the threading thing Joel.

RSimmons · #8 2009-03-20, 9:09am

Ace Glass sells all sorts of threaded (and other types) fittings, so you might check to see if they have what you need pre-made that you can join to the work piece. I buy from them occasionally for boro stuff. We had a big discussion about making threaded pieces here a while back but I don't think that a source for the tools to do it was ever identified. If it is I'd like to know myself.

Robert

beadbroad · #9 2009-03-20, 9:46am

I've wondered that for years. I've seen some beautiful S & P shakers, but that was before I started lampworking and they may have been boro.

ArtcoInc · #10 2009-03-20, 11:20am

Joel (the original poster) and I discussed this all at length in chat. He is using boro, and he's looking at making thousands of these.

We discussed how it is possible to fabricate a tool to facilitate making these threads in the glass, and the different materials that one could use. But, ultimately, his best option is to buy threaded fittings. A few minutes of searching found a number of sources for these threaded fittings.

Malcolm

RyanTheNumberImp · #11 2009-03-20, 1:09pm

These generally are not done by hand, the threaded glass jars and such that food comes in are mass produced on machines using molds.

Personally, I would not even consider it to be possible to create a thread freehand, you need to be incredibly accurate.

ArtcoInc · #12 2009-03-20, 1:41pm

Quote:

Originally Posted by RyanTheNumberImp

These generally are not done by hand, the threaded glass jars and such that food comes in are mass produced on machines using molds.

Personally, I would not even consider it to be possible to create a thread freehand, you need to be incredibly accurate.

I agree. Which is why I stated that, while it could be possible to make a mold (forget trying to do these freehand!), his best option is to buy threaded fittings.

Malcolm

szglassy · #13 2009-03-21, 7:02am

I have a tool to make the threads. It was custom made for a certian size. It's expensive to make and you need skill to make the threads.
If you are a novice, Malcom is right..you are better off buying the pre threaded boro tubes.
Sue

kathleen milligan · #14 2009-03-21, 7:12am

Sue, that custom made tool sounds interesting - I wasn't able to find pre-threaded tubes for soft glass. Care to share how expensive, and who made it?

szglassy · #15 2009-03-21, 8:47pm

I'm sure of you contacted one of the scientific suppliers in south jersey they could lead you in a direction.
They make the threaded tubes for scientific work and I'm not sure if there is a demand for it in soft glass. They would have to start with the tubes the particular size to match your cap.
My tool was very expensive and not for the novice.You need serious skills to use this thing, thats why I have it at someones shop who specializes in scientific work.
You are better off buying the premades.
Just my HO
Here's a pic:

One Dream Design · #16 2015-07-19, 9:23am

There is a mold available from us at One Dream Design, the hot glass tube is inserted and the shape is opened from the inside pressing the glass into the graphite from the inside of the mouth with jacks in a circular motion. The thread tool should not spin on the bottle /neck or tube form.... but rather follow the bottles rotation. (if the bottle or tube turns the graphite turns with the bottle.) When the glass cools slightly it can be unscrewed from the bottles neck couter clockwise leaving rounded threads. The glass really needs to be pushed into the threads, from the inside of the tube out.
Here is a link to a page describing it:
http://www.onedreamdesign.com/sink/s...hotglass.shtml

it works, but for some its not easy.

Its important to note the threads are not your standard pipe threads rather they are glass threads which are rounded, they fit your standard bottle closures.
We played around with all sorts of other tools, that applied pressure from the outside, none worked as well. All crimped the glass. the trick really is the "opening" of the glass into the graphite thread mold.

One Dream Design · #17 2015-07-19, 9:27am

There is a mold available from us at One Dream Design, the hot glass tube is inserted and the shape is opened from the inside pressing the glass into the graphite from the inside of the mouth with jacks in a circular motion. The thread tool should not spin on the bottle /neck or tube form.... but rather follow the bottles rotation. (if the bottle or tube turns the graphite turns with the bottle.) When the glass cools slightly it can be unscrewed from the bottles neck couter clockwise leaving rounded threads. The glass really needs to be pushed into the threads, from the inside of the tube out.
Here is a link to a page describing it:
http://www.onedreamdesign.com/sink/s...hotglass.shtml

it works, but for some its not easy.

Its important to note the threads are not your standard pipe threads rather they are glass threads which are rounded, they fit your standard bottle closures.
We played around with all sorts of other tools, that applied pressure from the outside, none worked as well. All crimped the glass. the trick really is the "opening" of the glass into the graphite thread mold.