Smokey glass!

[Purple Cobwebs]

I'm finding that I'm getting smokey streaks when I use clear glass. I use a hothead on bulk propane.
What am I doing wrong?

I've been trying to work higher in the flame, but it seems to have got worse.

Could my propane be running low? I'm still on my first cannister so I don't yet know how long one lasts.

Any advice welcome!!!!

[Donna@Rockin' Beads]

This can certainly be evidence of the propane running out.
The length of time it lasts obviously depends upon the size and how much you torch but if you move the propane bottle around you should hear some sloshing inside if it has any gas left in it.
If there is no or very little liquid inside then it's nearly empty.
However, even when there is still some liquid in it it can be near enough empty that you get the streaks.
HTH 

[sarah t]

not had this happen to me ....yet .....but from what others have said in other threads it could be a dirty rod......try cleaning the rods

and i think some glass can cause this effect from fumming so could be you are working to hot on what you are encasing ...its hard to work less hot on a hot head tho

guess its a process of elimination 

[SilverGems89]

As has already been said try cleaning your rods, then you can also try encasing with stringer, i find this is much easier for getting the encasing even from the start and then you dont have to work it for so long!
oh and what clear are you using? if your using effetre 004 people seem to have more problems than with the new effetre 006 clear
HTH

[Redhotsal]

It's burning, you're either too low in the flame still or the flame is turned too high up.  You HAVE to keep clear glass moving all the time - even 006. If you sit it in the flame without moving it and you see bright orange "scarring" starting to form, that is the surface starting to burn. Those bright orange scars will turn into grey straks when it cools.

You can "peel" off the obvious ones with pliers while it is still hot but it's much better to just not have them to begin with. It's unlikely that it's the gas doing this.

Try moving the glass around as you heat it.

[SilverGems89]

Sal i keep getting bubbling around the edges of my 006, is it just cause im getting too hot?

[Redhotsal]

When you start a new rod it has very sharp edges. If you could imagine what this would look like under a microscope the sharp edge wouldn't be smooth - it would be really jaggy like a mountain range.

Two things are happening - when you melt the end these jagged edges collapse and  melt down but trap air bubbles - so you often see a crescent shape of bubbles in the new gather.

The other thing that happens is that any pointy end presents a large surface area to the flame which means that it gets too hot too quickly - you might have noticed that you get more bubbles on the end of a pointy rod than you do with a nicely rounded rod - bubbling - if it's not trapped air bubbles - is usually a result of "boiling" the glass. i.e. it's not burning but if you get it too hot it will actually bubble. You can do this really easily with yellow for example. Any clear glass - even Lauscha clear will boil if it's too hot.  If you have a pointy end  - say on a dot you've just added to the bead surface take lots of care to give it gentle heat until it is rounded.

If I start a new rod of clear I'll gently heat the end and then pull off the scum bubbles with pliers. Make sure that you dont' leave a sharp point on the rod as you do this or you'll get more bubbles.

[SilverGems89]

Yeah i pull all my clear rods down into stringer cause they melt faster and i can apply them more evenly with only being on the hot head, so i think i must be boiling it! i'll keep trying and keep it a little cooler!

[Purple Cobwebs]

Thank you all! I'm using the 004. Today I turned my propane down a bit, and although it took me longer to make each bead, the results were much better!
I saw the bright orange streaks a couple of times,which then showed me where i was going wrong! So much easier if you can see it happening in the flame rather than 5 hours later when you take out of the kiln and cant remember what you did!!!!
So thanks especially to Redhotsal for the invaluable tips!
I'm on such a steep learning curve at the moment, but loving every hour at the flame!

[Trudi]

The other thing that happens is that any pointy end presents a large surface area to the flame which means that it gets too hot too quickly - you might have noticed that you get more bubbles on the end of a pointy rod than you do with a nicely rounded rod -

I didn't know that Sal  - but perhaps when I've had an unexplained patch of scumming, this could have been it!!

You learn something new all the time!