Tight Star Break

[Bois]

I hesitated to post this but everyone has a bad experience once in a while.

A customer with a '06 Lexus stopped by my tent location on Saturday for a 2 chip repair. One was a small bat-wing (repair went well) and the other was a start break which he said was over a year old and that it had recently begun to spread. There were 8 hair-like legs ranging from 1" - 2" like spokes of a wheel. It was sunny and about 60 degrees. Using Premium Band (DK), I was able to fill about 1/2" of each leg before the resin stopped. I used pressure/vacuum cycles, applied light pressure on each crack with probe on the outside, applied heat with cigaret lighter on inside of ws along with thumb pressure. Nothing helped in getting the resin to flow more. :eusa_wall I told the customer that I'd have to drill holes at the end of each break (pop bulls-eye) and fill from the ends. He didn't have the extra time so we made an appointment for finish the job yesterday.

Yesterday, temp in high 40's, cloudy and with defrosters on (measured ws at 60 degrees), I popped tiny bulls-eyes at the end of each break and tried to fill - again using Premuim Bond. Minimal success. Resin wouldn't flow desipte all the tricks known to me. I ended up with the inpact point and 1/2" of each crack filled and the end of each crack sealed. But the ~1" in between was not totally sealed (some were). Even though I knew the cracks would not spread anymore, it didn't look good so I didn't charge. Oh! I didn't want to drill any more holes since the break was in the acute area.

Anyone have suggestions on how to fill really tight, hairline cracks on star break? :eusa_thin

Dale...

[rescue]

I've only been doing this for 6 months, but here's my opinions anyway:

1. I use Glass Technology's hand-held injector (The Spectrum) which does a decent job but it's not the best vacuum system available (-18 inches of Mercury). Now that I've done lots of repairs, I've been thinking of upgrading to the machine-based "Maxim" system. They claim that the Maxim can create a "near perfect" vaccum (-29 inches of Mercury). If you can draw more air out of the break prior to introducing the resin, you should have a better shot at filling those long legs. All injectors produce plenty of pressure but a good vacuum is what really counts. I couldn't find any info on Delta's injectors.

2. Until recently I only used GT's MV (medium viscosity) resin for filling breaks. But after reviewing the literature, I found that they recommend the LV (low viscosity) for colder weather AND for star breaks. It seems to work better - the lower viscosity resin flows much easier that the heavier resin.

:eusa_shif

[screenman]

Bois,
You have told us how you attempted to fill the damage you seem to have not informed us of the way you dried it out. This information will help us diagnose your problems better. At this time and with the information you have given us I would say the dreaded moisture was your problem. failing that a complete lack of UV cover would also do the damage whilst repairing.
Give me some more info and I will try and give you a better answer.

[screenman]

Rescue,

Do not spend your money on more vacuum, most kits do an excellent job with very little vacuum. If you have a major desire for more suck just buy a mityvac and place that over the top of your injector, that will pull near on as much as you can at sea level. Which is about the -29 you talk about.

It is possible to do repairs using a system that has no only pressure and release. If anyone wants to know I would explain later, but I am sure most of you would understand already.

[GlassStarz]

You probably were loseing pressure you will see that a little resin comes up to the top of the cracks which means its seeping out. Put a cure tab over the area often this will give a minor seal if not take the uv shield off for a very short time leaveing injector on. place a cure tab over the legs this cures the top first gives you a seal then replace uv shield leave under pressure slowly the stubborn points will fill hopfully you havnt left the uv shield off long enough to cure into the break if your S O L

[Bois]

Screenman,
Even though we had a lot of rain last week, I didn't see any moisture in the breaks. Maybe I should have used the moisture evaporator like you're always preaching.:eusa_doh: Also, I watch for resin flow when I apply pressure. I didn't see any resin flow into the cracks beyond the first 1/2". It is possible that the UV rays, as few as there are here in winter, sealed the break thus not allowing any more resin to flow. Another :eusa_doh: .

Even after 2+ years of repairing ws, there's soo much to think about.

Thanks,

Dale...

[fix a chip]

How did you prep the Chip?
Correct me if I am wrong. But should the screen not be between through out the repair, like 70 - 90f???

Did you use a UV shield,

also, the injector may have been a little to tight against the chip causing the cracks to close up just enough to tighten the chip.

JMO

[Coitster]

Ok, this is easy. Drill a very small hole and take a needle and a flat tapper and point the tip of the needle at each crack and lightly tap. This will actualy open up the cracks. Don't tap too hard, just lightly. Then you can flex the legs, don't ever use a lighter to get the legs to flow.
David
Coitster

[AGSS]

:eusa_danc

Ok, this is easy. Drill a very small hole and take a needle and a flat tapper and point the tip of the needle at each crack and lightly tap. This will actualy open up the cracks. Don't tap too hard, just lightly. Then you can flex the legs, don't ever use a lighter to get the legs to flow.
David
Coitster

:eusa_danc Thats what Iam talking about!!!!!!!!!

Coitster's the man!!!!!!

I asume you mean to drill small hole in the center of the star?

And why no lighter

[Shepard]

I was trained with a lighter...I want to do the best repairs possible... why is it important to spend $50 on a thing that produces heat (just like a lighter)?

More importantly, Coister - you are the man!

When you say drill a small hole, do you mean shallow or with a smaller bur? At the end of each leg or in the middle?

Coister, when you visit Jackson Hole, call me - dinner is on me!!!