attaching/breaking off a punty

[elliebuff]

Hi everyone,
I have done a lot of lampworking, but have always used a mandrel. I want to look at small pendants or marbles, but I just do not "get" the way that people attach (I have seen it referred to as a cold attachment?) a punty and then get it off of the object without leaving any remnants of the punty glass. :???: I am sure that it takes a ton of practice and that is to be expected, but can anyone tell me the procedure to do this?

Thanks in advance!!!
Elenor

[Mr. Smiley]

One is hot and the other is not. I normally get the tip of my punty hot... just molten and then touch it to the piece I want to hold. If you get it just right, the punty will be sticky enough to grab and hold. Then when you want it to come off, you just tap it. It's a cold seal or a cold weld and should break right where they join. It uses the properties of stress to cause a weak temporary joint. I hope this helps. :love:

[elliebuff]

Very helpful! Thanks--I wasn't sure which part to heat. How do you hold it while you tap it off?

Thanks again!

[e. mort]

Depends of if it is a marble or a pendant. Pendants I pick up with tweezers, but marbles I use a marble holder I made by twisting the ends of a welding rod into loops, and then folding it in the middle so they come together like the tongs you use for picking up bacon out of a skillet. I learned how to make them in the book by Drew Fritts. You can order it from www.drewfrittsartglass.com

[elliebuff]

Great--thanks!! I will give it a try tonight...starting with the pendant. Maybe once I get the hang of things I can graduate to the marble.

[Cosmo]

One thing that will help (Stuart O'Grady taught me this):

When you attach the punty, pull back slightly. That will weaken the joint. Not to the point where it comes off, but to the point where it will come off easier and leave less of a mark.

[Wonker]

some people heat the glass punty up, then blow on it to help it form a kind of skin before they touch it to the piece the want to temporarily attach a holder on to. Woiks for me

[elliebuff]

Great info!!

One more stupid question...when you tap, I assume you tap the punty and not the pendant/marble/whatever?

[Heather/Ericaceae]

Great tips, off-mandrel gurus! *feverishly making mental notes!* Please keep 'em coming! -H.

[Cosmo]

Great info!!

One more stupid question...when you tap, I assume you tap the punty and not the pendant/marble/whatever?

Right. Tap the punty. And, when you attach a new punty, tap the old one off before the new one sets up completely. It will make sure the right one comes off.

If you have a punty that won't come off easily, grab the punty with tweezers as close to where it joins the marble/pendant/whatever, lay the piece on the table (assuming it's heat proof) or in a marble mold. Then tap the tweezers with another pair of tweezers, a handlehd marver, or something similar. That should break the punty off.

[Cosmo]

some people heat the glass punty up, then blow on it to help it form a kind of skin before they touch it to the piece the want to temporarily attach a holder on to. Woiks for me

That works well for me when attaching clear to clear, but it doesn't hold very well when attaching to color. Not sure why. I'm sure there's some scientific reason...

[firefreak]

my method (for boro)
heat the end of punty till soft,
quick pass on the marver to form pencil shape at end,
reheat just the point to red-white hot,
hold for 3 to 4 sec,
stick it up, then pull back.

to break off, I hold the piece, then tap the punty on the edge of marver or the bottom of torch body. you should have a nice clean separation. A little flame polish on the punty mark and off to the kiln.

you should be able to get it down in just a few tries.

BTW be prepared to loose the seal every so often! I have been told if you loose one in twenty your doing good.

[elliebuff]

Thanks so much to all of you--I will let you know how it goes within a few days! ;-)

[blancheandguy]

so let's see some pictures! Guy just started trying to make off mandrel pendants after three years of making just beads (soft glass) ... very interesting to watch it evolve. We love Stephanie Sersich and Dustin Tabor's .... Thanks for all the tips guys!

[rosebud101]

Two questions about attaching punties. I just don't get it. I also use soft glass.

1) The difference between a hot weld and a cold weld with a punty is that with a hot weld the punty is hot when you attach it to the bead and with a cold weld the punty is cold, but the bead is hot? Is that correct?

2) Do you need to use a boro punty with soft glass or can you use a soft glass punty effectively?

[metalbone]

...BTW be prepared to loose the seal every so often! ....

Excellent advice!!! Because it will happen.

It is always good to be mentally prepared (as well as have a quick procedure to follow) to quickly deal with a hot piece of glass that is either rolling on the table, floor, or God-forbid, your lap. I usually quickly grab the hotglass with tongs or use another readily available tool to keep the glass rolling to give me time to get the tongs before it burns a hole in something.

[metalbone]

I wouldn't use a boro punty on soft glass, sometimes not all of the punty comes off...you don't want residual incompatability issues.

[metalbone]

One more thing regarding losing the cold seal punty...this usually happens because the piece has lost its heat base in the area of the punty, and when you go back and heat the piece up, the differential expansion breaks the punty seal and you lost the piece to the table or floor. Often, you can hear a slight "tink" (the cold seal cracking) and sometimes there is a delay between the "tink" and when the seal actually breaks. In such cases, pull the piece away from the fire, quickly make a new punty and cold seal the other side, and break off and redo the old one. Don't be afraid to punty up in different locations on the peice as many times as is needed to make your piece.

Also, by heating the whole piece more frequently, you'll maintain the heat base in the area of the seal and will not lose the punty seal (at least far less often). Maintaining the heatbase is very important to learn.

[kiko]

For soft glass I use a metal (stainless steel) punty for the most part, chopsticks or a nice chubby mandrel work well. I'll only use a soft glass punty with a cold seal at the end during the final flame polish.

[ewdb]

firefreak's advice above made all the difference for me in learning to use a punty - i was just attaching the softened end of a clear rod to my piece and then could never get the punty off easily.

once i learned to marver the punty end into that dull pencil shape, couldn't believe how much easier it was to remove plus it only leaves a small amount of glass to pinch off or sometimes none at all