Ski Builders Forum

When building splitboards the most annoying part for me is to get the inside edges of the board to line up perfectly with each other during grinding and I've been trying to come up with a solution that makes quick and easy work of it.

So far I've had the following ideas:

- Take a belt sander or spindle sander and add a guide right at the lower edge of the sanding belt, clamp board half to a piece of wood with a straight edge with the inside edge of the board half overhanging that straight edge slightly, let the piece of wood ride against the guide so the board above rides against the sanding belt in a straight line.

- Same thing as above but with a router table with guide bushing and a carbide burr bit.

How do you guys make sure that your board halves fit together perfectly?

This part is very finicky. For me it's all smooth hand passes on my Montana side edger (old as dirt). A little uneven pressure though and it can't get it back! Keep me on the loop though. Venture had the tightest seams. Wonder it they would share?

Yeah, that's how I do it too atm. I'll start experimenting with the stuff I posted above and see where that takes me.

Never heard of Venture before, but they look like they know their stuff and the zero tolerance policy on their splitboard seams looks promising. Do you know anyone of them?

How straight are your inside edges after layup & baking? Still try to figure out how to do it the best way.

My current idea is to use a one piece core with center abs/pu stripe and route it in the middle for the edges. Dont know if this is practical....

Pretty straight, but every tenth of a millimeter counts. Lets say you have 0.25mm unevenness in both your edges, that could add up to a 0.5mm gap which is quite visible. Hence my efforts to get the edges perfectly straight after pressing.

Base material warps ever so slightly after cutting out, but it doesn't warp as much once the edges are attached. So you need to find a way to keep the inside edge of the base as straight as possible when attaching the edges and make sure that the edge you're glueing on is also perfectly straight. I cut bases on my cnc and glue on the edges with the base's inside edge clamped against a straight board with the edge in between. If you have a vacuum base template, just leave the vacuum on after cutting the base and attach the edges with vacuum still running.

chrismp wrote:Pretty straight, but every tenth of a millimeter counts. Lets say you have 0.25mm unevenness in both your edges, that could add up to a 0.5mm gap which is quite visible. Hence my efforts to get the edges perfectly straight after pressing.

That shouldn't be too hard with some normal edge grinding by hand. 0.25mm are taken away quickly with a rough file.

That's not really the point...the thing is to know where to take it off. You need the two halves to fit together perfectly, which is pretty tedious to do without any type of guide. And it's not just the edge but the whole sidewall above it.

Thanks for the info crismp. Maybe a 2 meter long magnet would help during glue up

Reg. you last post. The center edges are straight (or should be) so why not make a fence like on a tablesaw or on a stationary router!? You just have to get two long straight grindings, no?

Btw. did you compensate for the inner edges flex wise? I assume you will get a stiffer board with the same core profile (2 edges more, inside abs/urethane)

What about an offset router guide base using a flush trim bit?

Unfortunatley regular router bits wouldn't work as the edges need to be cut too.

Regarding flex, splitboards need thicker cores as the width of each part is much less than on a regular board. I usually add 0.5-1mm to the thickness of a regular board.

Guess I miss understood your question. Just looked at a Burton split today. Easily .5mm or More between the halves.

vinman wrote:Guess I miss understood your question. Just looked at a Burton split today. Easily .5mm or More between the halves.

Ha! Glad you now know what I was talking about...there must be a way to get this right! Only one way to find out if the methods I described above work. But that'll have to wait a few more weeks...currently studying for the bar exam, so no time in the shop at all.

Mini drum sanding bit in a drill press or router table, with a rear fence that the board slides along that just barely exposes the bit in front. will build and try. I will post results and photos in a week or two!

So kinda like a jointer works? Can't wait to hear your results

You could also try to add a small guide right below the sanding drum and clamp the spliboard to a board with a straight edge that rides along the guide. Think of it like a flush trim.router bit. This is basically the idea I was bouncing around above.