Glassing Question / Sharp edge around tail

I glassed 11 surfboards in 2005. I’m self taught with the help of “Glassig 101” and Swaylocks. I repair 2-3 boards per month so I get to see a lot of different shapes and glass jobs. One really big challenge for me right now is the sharp edge that all the glassers are putting around the bottom edge of short boards. I’m wrapping layers of tape along the rail per Glassing 101. I just can’t seem to get enough resin build up to make the edge super sharp. Glass on fins make it even harder to make that sharp edge. Some boards have a sharp edge from the tail to way beyond the fins…

Any tips would be great. Photos would be even better!

Thank you

Ray

Sting,

I’ve done very few complete boards, but glassed maybe 50 some years ago. I’ve never had problems when “building” sharp rails if work is well done on the shape stage.

The tail rails must be quite hard already on the foam. Shaping it completely square is unuseful because when you tight the glass when lapping, this hard foam edge becomes softer. Shape it just hader than the rest of the rail. If you have problems when lapping this rails try my trick: (if you lam bottom) flip the board deck up-mix resin and MEKP-wet lap area along the rails with paintbrush-flip board bottom up-lay glass and lam as usual-fold the laps as usual. This way, laps will fold easy and will kept in place by the first resin you spreaded along the rails, even if they are sharp.

Hope it helps.

Use masking tape to make a shallow dam in the tail area when hotcoating the bottom. You want the resin to pool in the area, slightly above the glass surface. Sand the outline first, then sand the flats to the sharp edge you want. I used to make the release edge in the tail sharp enough to cut paper with, I would use 220 grit wet/dry paper to fine tune the edge. If it’s not coming out the way you want, it’s very easy to dam and add more resin and sand again. It’s actually the final stage of shaping the board.

Of course, Bill knows from which he speakest…

Hard edge is pure resin, not from the shape and lam.

Howzit stingray. Not that hard to get those sharp edges. Before laminating the bottom you need to dull the shaped edge so the glass will wrap the rails in the tail. Before hot coating the bottom start your tape off about 1/3 back from the nose and run the top of the tape along the tuck line til you get about 3" before where the sharp edge will start. Now raise the tape so it's about 1/16' higher than the rail and continue around the tail and to the same spot on the opposite rail then lower the tape so it's running again on the tuck line til you've gone around the whole board. Now make sure the tape is down flat where it runs along the tuck line and where it's raised just run your finger along the middle of the tape in the tail. In the tail area you want a gap about 1/4" deep so run your finger along the middle of the tape so it's attached to the board but you still want the gap. Now fill the gap with lam resin ( you may have to force the resin into the gap with a brush) til it's higher than the bottom edge of the board in the tail. At the same time baste you laps to prevent sanding into them later. After the resin kicks you should now have a resin build up on the side and top of the rail and after hot coating there is plenty of resin to sand your hard edge into. Another thing is when sanding always sand from the opposite side of the board. Use a sandind block to blend in the raised resin where you lifted the tape into the tuck line and you can dull the edge til you get to where it's supposed to be sharp. Hope this is understadable to you, so much easier to show than to explain. Aloha,Kokua

On the same issue…

I have a board that was glassed for me and I wanted to harden the back edges. If I roughed up and cleaned the area, could I use the same technique to build up an edge? would sanding resing work in this case?

Howzit EarlyRiser, Shouldn’t be a problem,just don’t try to add to much resin,only takes a little and I use this when doing repairs in the tail area.Aloha,Kokua

that was a fine explanation, thanks from those of us listening in.

Kokua has the 411 you need. Hit the nail on the head. The only thing I did when I built up my edge was set something up to raise the tail up. It kept the resin from running out while it set up.

Thanks!

Waves comin’ this weekend, so I’ll be able to test how it works out. Can’t wait…

Paul

Sorry to go off topic but, what are the benefits of the sharp tail? or how does it affect performance compared to a more rounded one?

Clean release, little or no parasitic drag, you go faster.

Howzit schroeder, That’s why the tape is higher then the edge and if you use UV resin it won’t have time to run off. But I did it this way before using UV resin. With the amount of rocker in tail of boards these days you really can’t get the tail totally flat anyways, so the resin is going to flow either forward or backward. Aloha,Kokua

My boards are hotcoated and glassed by a friend so when I get them back, before I put the fin plugs in I put some tape on the bottom overhanging the edge about 1/4" around the back of the board from in front of each side fin, the area I want sharp. It’s important that the tape is flat and not pushed up the side. Then I flip the board over , top side up and put a bead of resin on the tape up against the rail, all the way around. I take a popsicle stick and run it around the back to make sure the resin is right in there. When it goes off I sand the bottom as usual and aim at getting my sharpness from sanding the rail. This is an extra step more than Kokua’s but it works for me since I don’t do the hotcoating. It also works for restoring or sharpening up a finished board.