surface bubbles on pressed beads
 

I was hoping someone could help me out with this. Maybe Gems, since the twistie recipes where hers (they are wonderful by the way). I am on a hothead, so that needs to be know. I will also try and photograph the problem. When I initially make the bead all is fine, however, when I shape the lentil and the got to fire polish I am getting bubbles tiny bubbles and I can't seem to get them out. So basically ruining the beads. Am I trapping air?, over heating? Any thoughts.

Thanks in advance,
Cherri

Hmmm pictures would help as I am not sure which twisties etc you are using. Bubbles in the whole bead or just in the twisties? waiting on pictures

Which tutorial are you referring to?

Here is a shot of the beads.

Thanks

pitting = too much heat

Also, some colors, such as black, don't like to be reheated without a chance to cool adequately in between.

Yes I find Effetre black will pitt as well if not treated with TLC.

Thanks no eff black

Yeah, I always think of that as boiling the glass. Sometimes it's really hard to firepolish without making a bigger mess.

This.

Double that.

It has been my experience that some glass does it and some doesn't. Same with frit.

Yep - I'm on a hothead too - esp when trying to get those delicious furnace glass colors on the surface. My hunch is that it elates to the amount of Mapp or somehow to the interaction at the border of the 104 and 96 coes.......doesn't seem to matter with me how slowly I melt the glass in........truly one of my biggest frustrations in all the time I've been making beads. There have been some batches of black that were plain impossible to melt without bubbling and black usually doesn't do this.

There was a bad batch of Vetrofond black way back in 2003 that was bubbly pitty horrible. Anything that I made bigger than 15mm would do that, and I was on the HH then.

Just wanted to add I'm on a HH using MapPro. There are some colors that just seem to loathe the fuel rich flame the HH kicks out. For me it's mostly teals (CIM Azure for example, pits like that from the word go, and Lauscha Bluetonium will do it if i let it cool a bit and reheat). Occasionally some greens will get pitty and of course EDP is her cranky self with the HH; I also have to be careful with Goldstone. Makes me wonder if copper is playing a role here.

Blacks, however, are well behaved for me ( I've probably jinxed myself LOL); CIM Hades, Tuxedo, Effetre Blacks, etc.

HTH a little!
Alli

Well, I did not get back to the pressed beads.. drat.. Ran out of time, so now have to wait until next week to try again. I am sure that I just got them to hot. I know before I pressed all was great. Then When I pressed them, I think they were still ok, it was trying to do the final polish that I got into trouble. I think I may need to let them cool a bit more in between. If that does not do it, then will rethink the frits I used. I am going to give it a go though. I really liked the colors I got, just have to get it to play nice with me.

What's "pitting"? Does that mean part of the bead isn't round or a pit has formed in the surface?

That is when you get pits on the surface of the bead. Know what a adult who had really bad teenage acne looks like? With acne scars all over their face? That's "pitted". In lampworking you can get pitting from microbubbles you get from pressing then reheating your bead. The little bubbles form like almost microscopic acne on the surface of the bead then pop leaving ittybitty tiny scars. It's really quite ugly and happens very easily on certain colors. My particular nemesis is anything in the turqoise family. It pits if you look at it funny, and screams bloody murder if you press and then reheat (which you want to do to remove the chill marks). I've heard (but don't quote me) that it is caused by the metal molecules in the glass chilling more when pressed then the glass molecules do, then reheating the metals boils them off 'cause you're reintroducing those cold metal molecules too quickly to the flame. They boil, pop, then leave the horrible pits. Or something. Sounds logical to me. :)

Ooh, just had an idea... I've had a lot of luck sticking any old bead in the kiln to hold for a bit then bringing it back out and reintroducing it to the flame slowly to reheat it and do more work on it. Maybe I can make a turquoise bead, press it, put it in the kiln for a while to even out the temp, then put it back in the flame to fire polish (i.e. get rid of the chill marks) and continue working on it. Hmm, I will try that.

Somehow it seems to happen in the last part of melting or polishing. I often get this when I melt murrini flat - I think especially if there is 96 coe in the murrini on 104 bead. Maybe it is metal particles on the surface as there is little sparking (I think). It really doesn't seem to matter how slowly I melt in...

I agree, it doesn't seem to matter how slowly I reheat pressed turquoise either, but ONCE I decided to reheat it so slowly you would have thought I was in a race for slowest snail. That helped. I think it just needs to be "ridiculously slow" which I consider to be a waste of my time. I KNOW it needs to be done slowly, I just have other things I'd rather do with my time. :^)

It's probably also about flame chemistry too. Maybe "too slowly, with a little too much propane"? My flame's a bit propane rich 'cause my oxycon's a little on the tired side.