Differences between soft and boro glass

[davelovins]

Hey guys,
I really feel like an idiot asking this question, but here goes. I have recently gotten back into glass and beads after a 20 plus year absence. I only did boro then. I have several sample packs of soft glass (104 and 90), and every time I try to use it, it turns a muddy grey color. I am using a National torch and think I am getting the glass too hot. Is there any tips or other info on why this is happening. I am a newbie again, so all input is welcome. Thanks

[Cosmo]

You are burning the glass. Work a lot further from the head of the torch than you are used to. Maybe 6-8" out.

[Firebrand Beads]

Isn't the National a pre-mix torch? Harder to get a nice neutral flame with those. You want a nice blue flame. Most of the lampworkers are using a surface-mix bench torch.

[davelovins]

Thanks,
That makes sense because I'm used to being so close to the white of the flame with boro. Even though I turn the flame down, I guess it's still too hot. I'll try that . Thanks Cosmo

[davelovins]

Thanks Jenny,
All I know is that the torch is like the one we used to use on boro only. But yes, when I try to bring the flame cooler it gets real sloppy. I even tried several different tips. I think I may need a different torch for the softer stuff. Thanks again.

[ArtcoInc]

Which National torch do you have? If you have the 3A, it is a pre-mix hand-held torch. Pre-mix torches *can* be used for soft glass, but surface-mix torches usually are preferred.

Also, which tip(s) do you have?

Soft glass is much more sensitive to the oxygen/fuel mixture than boro is. It is much harder to determine if you have a good oxygen/fuel mixture on a pre-mix than on a surface-mix torch. However, there are a few tricks ...

1) Don't turn the flame down. A smaller flame is even harder to get the right mixture. Instead, work further out in the flame.

2) Get yourself some glass that reacts to an oxidizing flame, and some that react to a reduction flame. Use these to help set your mixture, and find the 'sweet spot' in the flame.

HTH

Malcolm

[davelovins]

Thanks Malcolm,
I went out and tried working further away from the flame. It worked like a charm. I got a couple of beads with the color of the rods I was using. I Don't know the model of the torch, but its not hand held. I have several tips from the smallest cone shape to a large one that has a bigger brushy flame. I guess I need to put the boro down for a couple of weeks and just play with what I have to try and figure out the "sweet spot" like you say. I just saw your website and I have the 8M torch. I do have one like the handheld one that came with my regulator. Would that one be better for the softer glass?