by GreenLake » Wed May 14, 2014 3:46 am
"small" is relative.
Anything where the size of the glass patch is the size of your hand (more or less), or where a through hole goes down to 1" or less, is "small" in my book and usually not a problem, even on a vertical surface. I would not normally consider the "loooong" method for a "small" job like that.
I assume that you have followed the instruction and ground out some more laminate so that you have a nice shallow divot for your fiberglass work.
You can, and possibly should, use some plastic backing. For a "small" repair, the windows from toy boxes work well, they are nice and stiff, but still conform to the hull curve. You can press the backing onto the repair when you are done (using the "short" session method) and tape it down to hold everything in place while it cures. Should help in getting a (largely) level & smooth surface.
Second method is to build your laminate on the plastic and transfer the whole setup to the boat. That works better for repairs where you add a layer, not trying to precisely fill a hole.
Where a "loooong" job process might be useful is when the size exceeds "small", so that the glass is harder to keep in place, or where the inner hole (if there's one that goes all the way through) is getting large or complex. I had a case of the latter, where the hull no longer wanted to remain fair. In that instance, I first laminated a bit of a patch, let that set up away from the boat, then (in the green stage) glued it to the hole from the inside. That pushed the edges of the hole back into a fair shape. Now I was left with the "divot" case, but extended to form a wiggly trench. Easy enough to fill with the standard method, cure under a sheet of stiff plastic and be ready for sanding.
For that job, I used three phases.
For "small-ish" repairs, you do not need to use standard (runny) laminating epoxy (but if that's what you have, it's OK). Some of the stuff that's sold as glue is non-sagging, yet will still wet out glass cloth. This is true, in particular, for "Gel-Magic" from SystemThree. This one can be purchased in the caulk gun cartridge, meaning that you don't have to mess with mixing; and, as long as the glue in the mixing tip doesn't set, you can mix additional amounts by simply squeezing more glue through the tip.
I think I used that glue for both gluing the patch as well as wetting out some of the laminate in my repair, hence no issues with drips. Type "gored" into the search box on this forum, and you should get the link.
~ green ~ lake ~ ~