Talk to me about double hit starbreaks

[jayjacque]

Something that still gets me after a lot of years doing repairs is those wicked double hit breaks, not so much if one of the hits is just a bullseye, but the wicked double hit starbreaks connected, so if you just start filling one side, it also goes partly into some of the lines on the other side. So if you do that for awhile with the vacuum cycles and all and then cure before filling the other side, it seems the other side won't fill right. Something almost always still shows, one or two lines. Then I might try and drill again the lines that didn't fill all the way, but if they have been cured by that time, they seldom cooperate. That's the scenario, give or take a tweak or two. It's still pretty frustrating. I think I tried a time or two just starting out with pit resin on one side and cure it to seal off, before moving to the other side. Then afterward need to come back and drill through the pit resin on first side to get it to fill. That seemed to help, but I'm not sure?

[Nomad]

Carry some black electrical tape with you and put the tape over one side of the double break before setting up other side. That way you still have an uncured break to work on after the first one is done.

[ChipRite]

When I put the injector on the first break my dark towel goes over it - always. Once the first one is filled, I move the injector to the next, set up beforehand so you can use the top screw if you have a delta. Then tab the first one.
Aways do the lower one first so that runs do not go over the next one.
When finished, pit resin in both and tab, only then cure. The trick here is to keep just about all possible UV off until the end.
Nomad's suggestion of the back tape is another way and I sometimes use that method instead.
If they are further apart I run both injectors at the same time -again towel always over so no premature curing and thickening takes place until all legs are completed.

[jayjacque]

Nomad are you saying you go ahead and cure the first one before removing the black tape and filling the second? Is that why to have the tape rather than a towel over the whole thing? Still would like anyone else's feedback too if they want.

[GlassStarz]

Two injectors works if you can get the heads together otherwise I fill one put the cure tab on and fill the other without curing

[Brent Deines]

I almost always find that I can fill both breaks from one impact point, assuming the breaks are connected that is. If there are two impact points and the resin starts flowing out the second hole I just use a curing tab to seal it off until I am ready to cure.

On the rare occasion that both will not fill from one impact point, I fill one, cover it with a curing tab, and then fill the other before curing. As stated by GlassStarz, two injectors work fine if the impact points are far enough apart to set up on both at the same time, but since I always try to fill both breaks from one impact point, at least one break is always filled.

As long as I use a UV shield or dome I can wait to cure both at the same time.

[mafsu]

I also try to fill both from the same impact point. It work 90-95% of the time.
Place a drop of pit resin and tab over the pit you aren't filling. It takes more time. I've gotten dramatically better results using this method than filling both seperately.

[StarQuest]

As Masfu and Brent has already stated, if double hits connect...fill as much as possible from first impact point (sometimes you'll get lucky... and both will fill)

If you run into the situation when second damage stops filling, pit fill and cap first damage, then continue onto second impact area. I personally prefer to cure first hit before moving on to the second! Why? Simply to play it safe, first damage is filled, so why take the chance it might spread under pressure while working with injector on second hit?

Another thing to mention is when two hits connect and have two open surface nicks I very seldom use a vacuum first, because air could be pulled back in from second pit. I'll always start with pressure first and watch to see if second pit shows any signs of resin leakage. If it doesn't...then I'll apply the normal vacuum steps.

[screenman]

I would add to this by saying if resin does leak out of the second pit, place some normal resin and a curing tab on it before pulling a vacuum this will help bring resin in from that hole, Assuming your injector pulls a vacuum that is. Failing that the black tape method works well.