.................from the spitzer skunkworks shop......making your own fcs type boxes.....................

got some pms on the how to,"make my own boxes".............

.............here we go..............

i use the thick walled pvc end plugs..........you'll know they're the right size by the tabs on the fcs fins.

the tab should slide in the pvc plug easily but snug.

i use a few old odd ball fins to cast with,but you can improvise with just about anything,woods,plastics,metals,etc.

wax the fin w/ something (even old school surf wax will do).i use either carnuba or bees wax for a release.

mix up some resin and milled fiberglass and my fav .......you got it......exo-filler(disposable diaper absorbent).

mix it thick.......use a small amount of resin as possible,but still will work............(i use a combo of mekp and uv resin).

sand the interior of the plug or just wipe it out with acetone.

fill plug and insert the tabs of the fin also wax some tooth picks and insert them sideways like the fin screws go.this will be your pilot holes for you set screws.........after drying...........pull the fin out and sand off the excess.drill out the holes for the screws(abit smaller than the screws).insert screws and your done.

you can also add fiberglass cloth to the process,either in capping or lining the tab area.

remember not to make the screw hole to close to the tab hole ,it will be too thin,and it will crack out.

any questions ?


Definitely trying this out on my next board.  Thanks Herb!

Brilliant Herb, ive been wanting to make my own plugs for a while so might give it a shot, they are so expensive to buy…

Have you tried casting them straight into the board? , as in router out a hole in the board then pour the resin straight in the board and cast fin in place, im thinking this would fix resin straight to the board and no need for two steps casting and insertion… could do a high density foam where they would be cast?

yes i have done just that ,but it's a marked heavier.

pvc makes it abit lighter,and stronger.

and i never used a router ,just a hole saw.

btw: i like the high density foam idea.

i have a 2 foot by 1 inch block of clark hi-d.

use it for all kinds of stuff,



Yes to limit weight it makes sense to use the pvc as you said, thanks for sharing, got me thinking now to try a few things! 

Very nice.

Thanks, Herb.

you're welcome.

remember the key is not too much resin in the mix ,and watch you set hole placement.


 Im lacking in the ability to mind draw.

Any pictures please?

i'll see what i can do about some pics.



Thnaks herb, I especially want to see how the diaper stuff works. 

You can also:


Find someone with a vac chamber who can make a silicone mold of the plug you want (not that hard to locate) or silicone mold your own plug, threading and all. You will end up with a neat rubbery cup that I just pour my excess resin into after any glassing. once it dries pull out the resin and reuse the mold.. I think I have gotten about 30 pulls from each before they start to break down.

I dont use these on many boards however because of the tooling you have to do to the plug after you take it out of the mold - there is alot of excess resin that needs to be cut off and sanded.. and the molds are flush fit so it is a bit of a pain to set. Straight resin plugs are quite heavy. The cost can justify the work but mainly have used them for my own boards where I want to move fins around in different areas.


Will post some pics 

you right about time and money.

that's why the pvc plug is king.

a plug costs under 35 cents each...........complete!

and time................i do them while watching tv.