Hey Guys, Anyone have some tips on Finbox Surgery? On Wednesdays super fun lil' swell, I botched a wave and ended up with a fin to my ass. Fortunately my ass is okay and the wetsuit is barely damaged. But the board needs surgery.... As you can see, the front of the box itself cracked (along the screw-plate track), and separated from the board, pulling up some foam with it. I cut away some glass so it could dry properly, now I'm seeking advice on how best to move forward. I do not have a router. My plan is to use a dremel to excise the box, piece by piece. Then I will make a outline jig and use that to excise the surrounding q-cell filler. After that I'll check to see what kind of shape the foam is in underneath the box, and proceed accordingly. I plan on using another Bahne Box but if there's a good reason I should use Factory, let me know. Thanks in advance guys. Help me fix this 'finxbox'
Definitely not gonna do that. I've fixed many a ding and I'm sure I could handle this. Nonetheless, it's my first repair of this nature- so I'm looking for tips that will make it less painful.
Good luck. I can fix a sagging house but I am LOST on ply/foam/glass stuff. Didn't pay attention in chemistry.
If I wanted it nice id take it out fill the hole with some kind of filler and re router it. but its a longboard id just say f it pull it out squirt some 5200 in there push it back in cut whatever excess comes out off with a razor or don't ,whatever, and surf that log til it breaks. My log has multiple unacceptable repairs on it for years now and it still surfs fine.
Wow! You must really have a hard ass. Are you sure that wasn't a rock? Anyway, it's easy to build a simple frame for a jig and blaze that out with a 1/4" router bit. I just use a simple frame made from 3/4 pine that I clamp to boards I'm building with plenty of padding. Just order a new box to go in there. Take shallow passes with your router and work your way down. p.s. Nice looking vintage bike just out of focus.
theres nothing wrong with the fin box.at least from what I see in the pics. its just poppin out of the board.
Nothing to add about the repair, but the bike caught my eye. I'm guessing modern interpretation of vintage. Triumph maybe?
Slashdog, This repair is actually not too difficult, even if you have not done much ding repair/glass work etc. Assuming your board is not epoxy, and you have or can borrow some basic tools, just proceed carefully and you will be all set. As carefully as possible remove the broken box. It is always adviseable to replace a finbox when there has been an impact severe enough to pop it out that far because if you just fill and re attach it, there may be cracks etc that will allow water in that can leach down the stringer over time. Thats why you see older boards with that brown area along the entire stinger with no apparent ding or delam. Clean and dry the area. I cannot stress the importance of the drying, if you do a finbox with moisture still in the foam, you are going to end up with worse damage later on. If you can bring it in the house, or your garage/basement is heated all the better. I sometimes put them in my attic to dry in the winter because of the climate here but just be conservative. When you think it's dry, wait another couple days. Assuming you have a new box, and have the area around the old one prepped, mix resin and some q-cell or cabosil and generously apply it to the hole where the box was. Be sure to run a popsicle stick around and push it into all of the nooks and crannies. Be sure to use enough catalyst so the resin does'nt soak the foam and leave any voids. This will be dependent on temp so pick a warm day or use a heater. Push the box in and you want some of your resin/filler mix to come out all around the box, obviously. When this has hardened, sand flush. The box may be slightly above the bottom of the board and has a different density so be carefull if you are using sanding tools that are powered. You can easily go off the box and into the board and create a new repair to make. Now you can choose based on how tight your removal was to either fill in and hotcoat or my preference is to glass a patch over the new box. If you choose to glass, sand around the box to promote good adhesion, tape the OPENING ONLY on the box off, so run masking tape along the top and with a razor etc, remove the tape on the edges so the glass can overlap the entire outside of the finbox. Now, put a patch of glass, oval normally and going out 3 to 4 inches from the box all the way around. Once the resin has gelled, take your razor and cut the glass along your tape on the box and peel that strip off. You should end up with the opening clear and a layer of glass all around the box. Last step is sand/hotcoat/sand like any other repair. I forgot to mention to place a fin in the box when you install it so you can see if it is square, not tilted and tape or prop it in that position until the resin is hard enough on its own. Good luck, I'm sure it will come out fine. Edit-Looking at the pic again, I def. recommend doing the glass patch due to the damage at the front of the box where that chunk of foam is gone and the glass peeled off.
My advice... Take a utility knife and a straight edge and neatly and cleanly cut just through the glass all the way around the box about an inch out, and carefully peel off. This gives you a margin all the way around the box within which you'll work. Also remove any delaminated areas, out to good glass, and do the same. Then, cut down around the box on the outside of the the bonding resin to release it from the surrounding foam. Keep it as close and tight as you can to the routed hole. Dremmel though the bottom and ends of the box where the box is bonded to the stringer to release the box from the stringer. you can do the rest of the bottom of the box, too, but if you put a fin in the box and wiggle it, you can probably pull the box out with little difficulty, considering that it's compromised already... hard to tell from the pic, though. Square out the damaged foam and cut a piece of new foam to fit tightly into the square hole. Use Elmers white glue, and just a thin veneer is all you need. Once dried, sand it down and clean it up. You should be left with a clean foam surface, and a clean box hole. Sand the surrounding good glass, and laminate 3 layers of 4oz cloth over the area, overlapping onto the sanded good glass. Don't worry about cutting a hole through the cloth for the box hole... just lay the cloth over the box hole. You can even lightly spray the area with Super 77 to get the cloth to tack down and not slide around, but you don't have to. Just a mist... and mask off the surrounding areas with newspaper if you do it. Laminate the cloth neatly so as not to soak the cloth over the box hole and have resin drip through. You can do this one layer at a time, if you're not an experienced glasser, but it sound like you are. Once cured, carefully hotcoat the patched area, again making sure no resin drips down into the hole. Once cured, cleanly cut along the box hole edge using a straight edge and a new razor blade. Mix your filler and resin and install the new box. Grind down the box lip to the level of the bottom. You can patch over the box at this time, as described above. Good luck. Post pics.