Recently i have been fixing a lot of boards and filling a lot of big gouges. However it seems like etiher the filler itself will crack when surfed or the edge of the filler and ding will eventually seperate. My general method for ding repair has been to cut the bad glass away leaving a beveled edge leading into the ding, then i remove the moldy foam, then i mix up resisn and q cell, then lay 1- 2 layers of 4 ounce glass, then rough sand, then hot coat. After many a cracked ding repair i am wondering if there is any sort of filler that has the same flexing characteristics of foam and glass. Does the diaper filler flex any? would more glass on top of the filler prevent the cracking. thanks. Darren
Okay, several possibilities arise- First, it might be that your resin is mixed too hot. That will cause it to heat up, crack and fail. A thick layer, like resin plus filler used to fill an area, needs far less catalyst than you’d use in glassing. Second- how far are you lapping the new glass over onto the original glass? You should have at least 1/2" to 3/4" on all sides. If you’re just taking the glass to where you’ve cut away the old glass, it’s pretty worthless, it’s not accomplishing anything and the repair will break and will fall out. What I do, whenever possible, is cut the old crushed foam free from the underside of the old glass ( which also keeps as much of any airbrushing or color as possible )while keeping as much of the old glass as possible- it may look crushed but when wetted out with new resin it’ll look fine - fill using a fairly stiff cabosil/resin mix with the old glass on top of the filler ( be careful to make certain that there’s no air bubbles in there) , sand the repair to the contour of the board and then glass over the whole shebang with a minimum of a half inch ( usually more )lap onto undamaged original glass. This ties it all together nicely. Flexible filler- well, don’t bother. First, if it’s not pretty rigid it’ll break away from the glass. Also rigid filler is fine in use. The thing is, when the board flexes some, the foam under the filler will compress slightly to accomodate it. Hope that’s of use. doc…
Darren. I also had this problem in the early days of ding repairs.The glass would always crack around the edge of the Q-cell.I had to find a better way, I did’nt want people coming back unhappy.What I do now is prepare the area as normal and glass it first with a couple of layers of 4oz. Push the glass down into the hole.Fill with Q-cell,sand the whole area so it is nice and fair.Then glass over the whole area with a big overlap,say an inch.You want the overlap to be on the origonal glass where the is some body to fair it in.Then hot coat and finish as usual. The hardest thing about this kind of repair is to know how far to sand.It is a trial and error thing,to much and you have a soft spot around the ding,not enough and you have a bumpy finish.This may sound like a drawn out process but not as drawn out as having the board come back and re repairing the board free of charge.Hope all of this babble helps. David.
another tip - before fixing the ding, sand down through the weave around the ding so that when you patch over it and sand smooth, the patch is flush with the rest of the board without having to sand most of it away. This will give you a ding repair with no bump (if you are good) and plenty of strength. Most of my repairs that have failed were because i did not sand down far enough before the fix, so when i sanded the fix smooth, i sanded most of it away.
Howzit Singles, What causes the Q-sel to crack is the ding area is not totally dry when you patch it. After you cut away any fiberglass and are ready to fix flush the area first with fresh water to get rid of the salt crystals that remain. Then make sure the area is totally dry before filling. Remember water and resin don’t mix and that’s why it cracks. Aloha, Kokua
too hot of a resin mix causes the resin to set faster; and actually to be harder but not shatter resistant. Slow cure== Shatter resistance is improved. the same is true with Dentists and their amalgam, the ones that truly care if your fillings last more than 20 years(quality work) will let it cure more slowly, the others are just expedient and mix up hot batches.
Try putting a little milled fibers in your cabo-sil mix too, it works good,like fiber-mesh in concrete.