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Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 22nd, 2012, 11:13 pm
by screenman
Just a thought on this again this morning, I use a magnifying glass I could certainly not see the very small air bubbles without it that need hooking out, prior to curing.
Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 23rd, 2012, 5:11 am
by ssbogger
glassdoctor wrote: Try this and get back to me.... drill a dozen holes of any shape and size and fill them with resin, making sure none have any bubbles prior to curing of course, and cure 6 with a tab and 6 with no tab and see what you get.

I might do that. Maybe even 4 with tab, 4 no tab, and 4 curing tape. I did 5 repairs yesterday successfully with no air in the pit by using curing tape. The "flowering" has subsided probably 50% by using little to no thump pressure on the injector during the pressure cycle BUT my time per repair has increased 100%. It seems that the air in these bullseye's I'm making just doesn't want to come out with anything less than 45 min worth of work...
Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 23rd, 2012, 6:17 am
by glassdoctor
If you make the holes a little bigger and deeper, I think you will have more success in your bubble making.

Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 23rd, 2012, 12:31 pm
by ssbogger
Here's an example that I did today using NO thumb pressure. It was a small halfmoon with a short crack running out either side. Procedure went like this:
Practice glass: PGW Solarshield
Made the break
Added water
Wiped off excess
Moisture evaporator for 15-20 sec <-- I let this thing heat up before I put it on the glass thus getting 15-20 seconds of full heat. Is that correct?
Heat exchanger ~30 sec.
Measure temp of break - 85F
Surrounding glass 83F
Apply bridge assembly and put into pressure cycle.
The break starts filling nicely and I don't use any added pressure.
Go thru 3 press/vac cycles, pull the assembly and cure.
This is what I ended up with:

Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 23rd, 2012, 1:03 pm
by glassdoctor
I think you need to give it more tome to cool. The internal glass/pvb layer could still be warm enough to cause issues even though the surface temp was down to 85.
Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 23rd, 2012, 2:48 pm
by ssbogger
glassdoctor wrote:I think you need to give it more tome to cool. The internal glass/pvb layer could still be warm enough to cause issues even though the surface temp was down to 85.
That could be it. About how long should it take for it to cool to a working temp? I mean, if you use the moisture evaporator and then the heat exchanger -that whole process only takes 2 min and brings the glass from 85f to as high as 200f and then back down to 85-87f. So give it another 5 min after that?
Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 23rd, 2012, 3:02 pm
by puka pau
Since this seems to be happening consistently on this glass, it might be a construction defect. Try doing a few repairs on a different piece of glass and monitor your results.
Cheers;
Puka Pau
Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 24th, 2012, 7:54 am
by ssbogger
puka pau wrote:Since this seems to be happening consistently on this glass, it might be a construction defect. Try doing a few repairs on a different piece of glass and monitor your results.
Cheers;
Puka Pau
I'll give that a go. I'm in the market for a small piece of glass to take around with me to use as a display anyways.
Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 24th, 2012, 9:52 pm
by Mr Bill
Fix the chips on the windshields of your friends and family for free.
I think that is better practice.
Way more varied.
Re: Newbie intro / Air Bubble and Flowering issues
Posted: August 24th, 2012, 11:23 pm
by screenman
Mr Bill I think before going live it is wise to perfect on a practise glass.