Thinfire and fire polishing

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Michael Harmon
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Joined: Wed Apr 24, 2013 6:58 pm

Thinfire and fire polishing

Post by Michael Harmon »

When I do a strip design piece I fire it face down first on thinfire, and then coldwork ithe texture left by the thinfire down so it will fire polish face up the second fire. I have been using the diamond pads but lordy thats a lot of work. I don't want to spring for a sand blaster right now so I'm going to use silicon carbide abrasives. So my question is ....What grit would I use to erase the thinfire texture so that it would fire polish at slumping tempratures? I dont want to use subsequently finer and finer grits I want to use just one if ppossible.
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Stephen Richard
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Re: Thinfire and fire polishing

Post by Stephen Richard »

A silicone carbide abrasive of the same girt you are using right now will be just as much work as the diamond. There are several books on coldworking and one on sale on this site that is very good.
You need to move from a coarse grit through finer ones to the surface you want before firing.
Something like 100, 200, 400, 600/800 will give you a surface that is easy to fire polish. Leaving it at 400 will require a little longer/hotter fire polish.
After the first grit, use a paint pen to cover the work area, let it dry before using the next finer grit. This will tell you where you have not yet removed the scratches from the previous grind. Repeat for each grit size.
Steve Richard
You can view my Blog at: http://verrier-glass.blogspot.com/
Valerie Adams
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Re: Thinfire and fire polishing

Post by Valerie Adams »

Pick up a copy (or download) of Paul Tarlow's "Coldworking Glass without Machines"; it's a great resource for what you want to do.

If you're not willing to move through different grits, you'll spend a lot more time at a fine one. It really doesn't take much time at each grit to do what you're wanting to do, and the results will be worth it.

If you don't already subscribe to Bullseye's Online Education forum, they just posted a video recently that also shows how to coldwork by hand.
Michael Harmon
Posts: 9
Joined: Wed Apr 24, 2013 6:58 pm

Re: Thinfire and fire polishing

Post by Michael Harmon »

Excellent replies Stephen and Valerie, thanks. Here is the funny part I suppose. After my first strip design firing on thinfire, I saw the texture and assumed that It would fire polish out. And basically it did to the eye, but the surface felt "lightly dusted". So my next piece I assumed that a "light sanding with my red diamond pad would do the job of removing the dusty feel. All it did was shave off the tops of smooth micro mounds left by the thinfire so that the still smooth valleys were now in relief so to speak. So now as you can see in the photo a micro texture remains Thats kinda cool, but both of you guys are right about the level of gloss I desire. Going through the grits. Thanks!
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Michael Harmon
Posts: 9
Joined: Wed Apr 24, 2013 6:58 pm

Re: Thinfire and fire polishing

Post by Michael Harmon »

I went to Bullsye and watched the video on silican carbide powder. I watched it several times. It seems to me that they allude to being able to stop at 400 grit if you wished to fire polish at that stage. Its an indirect delivery of information that subtly hints at what I'm saying. Could be wrong of course.
Michael Harmon
Posts: 9
Joined: Wed Apr 24, 2013 6:58 pm

Re: Thinfire and fire polishing

Post by Michael Harmon »

OOPs I should be posting on tools and techniques.
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