# fin cant jigs

just offering:

ive read a lot about people taping their jigs at correct angles, and a few other things. what i decided to do is make a perpendicular slide at various angles that slides across the fin jig, keeping it at the desired angle. thus far it has worked wonderfully for me and with great ease.

the only modification that may be necessary is if you are using overflows that are one piece (such as the yellow ‘figure 8s’ from FCS). i use the white zig-zags and it works fine.

Does the jig assume a relatively flat bottom?

I guess it’s more my ignorance of how cant is calculated.

Seems clear that if the bottom is perfectly flat and level, then measuring would be straightforward.

If the bottom is, say, a V, then is the cant computed perpendicular to the angle of the V at the location of the fin?

the bottoms are flat, i have had that problem actually, and what i did was two things:

one, i made a cant jig that was barely wider than the angel needed, thus it was only in contact with the board within the thickness of the plug. these were unfortunately very brittle, and instead what i did was…

two- since the V is deeper, just know that the part of the cant jig that is closest to the stringer would be slightly off the board and make sure that the jig from the plug out to the rail was flat on the board.

Quote:
Does the jig assume a relatively flat bottom?

I guess it’s more my ignorance of how cant is calculated.

Seems clear that if the bottom is perfectly flat and level, then measuring would be straightforward.

If the bottom is, say, a V, then is the cant computed perpendicular to the angle of the V at the location of the fin?

I use various triangle shaped jigs, and this (pic below) laid against a square or tri-square over half the bottom to check the angle of concaves then add to the desired cant for the proper jig to use.

HTH

Posted this before, but… I’ve used the adjustable angles with tape as well, still managed to screw that up. Given that it’s supposed to be summer now, the temp is low 50s F and using epoxy is possibly contributing to the problem as the plugs want to float and the epoxy takes forever to set. I added the cutout on the angle piece after one of my previous jigs where epoxied to the board… I also add some waxed tape to the jigs when using them so the epoxy won’t stick.

That looks like it will work fine Haavard. I just use my angle jigs against a dummy fin jig for fcs plugs. If I want to set a fin angle from the horizontal on a vee, I just level the board then use a 2ft level from the stringer out over the fin area and check the angle against a tri-square, then subtract to use the proper angle jig.

HTH

The things I mentioned may be overkill. For all practical purposes I usually just eyeball it and guess. It’s usually only a 1/2 - 1 degree. Maybe 2 degrees on a serious concave or vee. It’s just experience. You might want to use the overkill at first, then later you will develop a feel for it.

Quote:
Quote:

Does the jig assume a relatively flat bottom?

I guess it’s more my ignorance of how cant is calculated.

Seems clear that if the bottom is perfectly flat and level, then measuring would be straightforward.

If the bottom is, say, a V, then is the cant computed perpendicular to the angle of the V at the location of the fin?

I use various triangle shaped jigs, and this laid against a square or tri-square over half the bottom to check the angle of concaves then add to the desired cant for the proper jig to use.

HTH

OZZY, where can one pick up something like that??? i could use that for my glass ons (retros and performance thrusters)

Building supplies might have them. Harborfreight does. I got mine from Walmart about 10 years ago. They should be pretty easy to find.

EDIT: Btw, you might want to check zero against a square on it. Mine was approx. 1 degree off.