I'm having lots of problems with clear-it always ends up with brown sooty streaks in it and I'm not quite sure why. Is is just that I am holding the bead too far down in the flame or something else? I'm using vetro clear on a hothead and I find I have to hold beads fairly low down to get the glass to actually melt. I'd really appreciate any advice- I have attempted encasing a couple of times bit it always ends up looking a complete mess :(
Thanks,
Sal
Hi Sal have you cleaned your glass ?
Yep - used something alcohol based and then just some water to clean it off (paranoid of going up in flames!)
what gas are you using on your hothead?.. black marks are often related to soot - which may be caused by chemicals in the gas not burning completely... try running your hot head at max, and tapping it gently with something.. if you see little "shooting stars" in th eflame when you do so you are dislodging particles of soot which are burning up..
did you get the vetro from us?.. we can check our batch but so far we have only had positive results with it?.. if the glass has been wiped down and is clean i must say i would be looking at the gas itself introducing impurities into the flame.. the hothead is an excellent torch (just ask sarah!) but it needs good clean fuel..
8)
It's on bulk propane. Had the same problem with effetre clear (I got both from Martin). I've not had the same problem with any other transparent colours, just the clear. I'll have a go at hitting my torch tomorrow! I always run my torch on full (I have to turn it right up to light it and just leave it there).
just gentle tapping mind!!!...
do you have pics?.... 8)
I shall crank up my camera tomorrow when it's better light-no laughing though!
Sal - I have just gone bulk, and I experienced the same (with vetro clear and other trans glass). When I went bulk, I had to have a new torch bracket, and I found that I just needed to lower the head of the torch a bit rather than trying to work further out, and the sooty streaks seem to have stopped.
Also, on the first session, I thought it didn't seem hot enough, but somehow that has resolved too.. have no idea why!
How long have you been on bulk?
Quote from: Sal on November 08, 2007, 09:52:15 PM
It's on bulk propane. Had the same problem with effetre clear (I got both from Martin). I've not had the same problem with any other transparent colours, just the clear. I'll have a go at hitting my torch tomorrow! I always run my torch on full (I have to turn it right up to light it and just leave it there).
Hi, I'm running a hothead on bulk and used to have it turned up full until someone on this forum suggested turning it right down almost until it goes off. I tried this and the results are so much better. Unfortunately I can't find the original post.
I read recently that torches that are run on Mapp can be difficult to light when you first switch to propane. Maybe there is a build up of something? Maybe run it on high for a bit without any glass , then try again?
there are sometimes tiny impurities in the propane tanks and the problem seems to be worst at the start of a tank and at the very end?... maybe the mapp gas leaves small deposits in the body of the torch that the higher flow rate of the propane dislodges?..
mary, dig your avatar!!
;)
;D
Thanks everyone, I'll give all of that a go. I actually went straight to bulk so my poor little hothead has never known mapp! I'll try to put some pics up later on.
Sal
I have attempted to attach a photo of the sooty bits. Hope it works! Sorry about the awful beads (and terrible photos!)
They're not awful beadies, theyre lovely :D
Hi Sal,
They are not awful, they are gorgeous, one lampies fugly is another lampie masterpiece!!
Keep going love,
KJ.
You're burning the glass. If you look at the glass with your didys on and you see bright orange "scars" on the surface you are over heating the glass. These scars will turn into black sooty marks. You can pull them off with tweezers - but it;s better to not have them in the first place.
Try keeping the glass moving - never heat the glass in the same place for very long. Try and keep the glass "blunt" - if you pull the clear into peaks you will have a big surface area relative to the torch at the "peak" and this will burn like a bugger - try and keep the glass rounded. Hard to explain.
If you have your hothead turned up to the max you are almost certainly burning the glass - I'm suprised your beads look so good(!) - I don't think I ever had the HH turned on more than halfway when I used to use one. Sorry for the backhanded compliment there - you're beads look really quite good - they'll be even better when you don't heat the bejeebers out of the clear!
Thanks for your help Sal, I have tried turning my hothead down today-waiting to see the results when I take my beads out of the vermiculite. I will try reducing the heat even more next time. As I said, it only happens on the clear-all the other colours (transparent and opaque) seem to come out fine-very strange.
Thanks again to everyone for all your help,
Sal
The clear burns very easily -even the Vetrofond. Lauscha clear is lovely - really easy to work with and hard to burn.
Can you actually see when the glass is burning? You should be able to see it burning with practice.
If you have melting without burning, the glass should glow a nice even orange coloured glow. You can only really see this with didymium specs on. A burn will show up as a ragged orange streak - much brighter than the other bits of the glass. If you can see these you will have burned the glass. Try heating the bead higher up in the flame - even though it will take longer to melt you will prevent the burning.
You'll notice on your middle bead that the sooty mark is circular? This is because the encasing over the spot started off as a peak. You burned the very top of the peak and as it spread out it carried the burn mark into a sort of "C" shape around the centre. With a bit of practice you will be able to see when you burned the bead before you take it out of the vermiculite. I still burn my clear but you can often pick off the burned streaks with fine tweezers or by "peeling" the glass. You may want to pick off the end of your rod before you start encasing as people often burn the clear before it is applied to the bead.
Try to avoid these bright streaks and you will cut down on your burns. It's very hard with a Hothead to keep your clear true - but if you can perfect it on a hothead it's fantastic discipline and you'll be so much better when/if you progress to a larger torch.
Hmmm....I suspect that as you are a Sal you are naturally impatient - seems to be a trait that goes with the name! (Just kidding!)
Sal
Me? Impatient? Never!!!!!! I shall just have to try and contol myself and just take things a bit more slowly. I see what you mean about the semi circle of sootiness-it's often like that, especially when I've put the clear on in dots. Thanksyou for explaining it so well-it makes complete sense. I'll have another go later on (I still burnt the clear yesterday despite turning down the torch). I'll see if I can turn it down even more and be more patient (oh dear!).
Sal