i know that this is a complete amateur question, and i know that this is talked about all the time, but im really not sure of what the exact process is to glass fins onto a board. would someone care to help me out and describe in detail what is necessary for glass-ons?
it would be very helpful.
thanks.
Here’s how I do it:
First, I cut patches of cloth (6oz) which are oval in shape and which will cover the entire fin and lap down onto the surface of the board about 2 inches. I cut 4 per fin (two each side). Accordingly, if you are doing a thruster, you will need 12 football patches.
I then take woven roving and create fin rope. Essentially, I cut 7 pieces of woven roving alittle longer than the fin base to make one ‘rope.’ You’ll need two of these per fin.
Figure out the fin placement (perhaps you already have) and lam the board. Before you hot coat, set the fins.
I use a hot glue gun and a thin line of glue to tack my fins in place. (Some will not like this, others will support it.) I do it, and the results have been fine and durable in my limited experience.
I wet out my rope by dipping it in resin and wringing it out. I then lay wet rope on either side of the fin base.
Next I use a paint brush to wet the fins with resin (I use epoxy). Then I wet out my oval patches (also referred to as football patches) with resin on a sheet of wax paper. I take two wet out patches of cloth and apply them to one side of the fin. Press the cloth smooth against the fin, like you’re laminating them. The patch should overlap the outside of the fin a little (maybe 1/2 inch). The patch should also extend down onto the bottom of the board. My patches extend from the fin onto the bottom about 2 inches and that seems to work. Once you’ve applied the patches to one side, put two on the other side in the same way. The rope at the base of the fin should be used to create a smooth transition for the cloth from the fin to the bottom of the board. For clarity’s sake, the rope is inside the cloth–its applied first.
Join the four patches at the edge of the fin by pressing them together with your fingers–this is why you wanted the cloth to extend alittle beyond the fin. There will be excess cloth sticking up from the edge of the fin.
Let the resin gel or go off as the case may be and use a razor or exacto to trim the excess cloth from around the template. Don’t let it get too hard or this will be very difficult.
Hot/ fill coat the board and the fins, then clean 'em up by sanding… sanding, more sanding. Since I use epoxy, I usually do my fin clean up sanding before the fillcoat but this may be different with poly-hence my statement to hot coat first.
This is essentially the method espoused on the glassing 101 video with the exception of the hot glue thing.
The instructions given above are very very correct. Great job guys. I do no quite agree with the glue gun, but to each their own. Good to know not everyone uses plugs. The best thing is the number of roving strands. After many years of doing glass-ons, 7 strands is the magic number. Also, not sure if it was noted, but when laying the saturated strands along the base of the fins…criss cross the strands in the front and back of the fin. This will give you an area to get a good flow when sanding and additional strength.
thanks so much guys. very much appreciated.
Maybe this should go into the reasources for future reference if its not already in there…
Chris
The only thing I do differently these days is I don’t run the cloth all the way up the fin. I think that if you start with a perfectly foiled fin, why cover it with cloth. I make two patches, one just smaller than the other, that run only about an inch or inch and a half up the side of the fin. I put the smaller patch on first, then cover it with the bigger one, then fair it out after it’s cured. Hotcoat the whole thing. Sand.
This puts the strength where you need it, and not where you don’t, plus saves weight.
Bro, call my business partner, Jerry. He has been in the industry for 40+ years. He’s shaped, glassed, glossed, finned, and sanded for Brewer, Takayama, and others. If you want to know ANYTHING about fins. He’s your man. Just keep the calls to a minimum, and tell him you are a friend of mine (Dave Falkenau) from Swaylocks. Here’s his number: 760-889-4162 or 760-476-0799.
