Splitboard halves gapping

[kFergie]

Hello all, noob posting here for the first time. I have read through the trove of information available on this site and am eternally grateful for how much time and effort everyone gives to provide others in the community with guidance and information. I hope to gain enough experience to be able to do the same and give back someday. Anywho, this summer I built a press (modeled after Goz's plywood/steel hybrid) and pressed myself a couple of splitboards. Upon visual and hand-feel inspection, I'm feeling optimistic that I'll be surfing some amazing pow this winter, but I haven't put them to the test quite yet, so that remains to be seen.

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One thing that I've noticed is a recurring issue that I have, and I'm a little puzzled by, is that when I cut out my two split-skis, the straight center edges don't line up perfectly. They either gap in the middle or at the tip and tail, usually by up to 5 mm, ughh. I am puzzled by this because I use a perfectly straight MDF template and flush cut router bit to cut out the base sheets, and they line up perfectly after being cut out. Once I glue on the inner edges, the two halves don't fit together perfectly. Since the edges I get come rolled up for shipping purposes, I try to straighten out the edges before gluing them on. I feel like I get pretty close to straight, but apparently not straight enough. Is this the reason for the halves not fitting together perfectly? If so, any expert tips on fixing this issue? Pics attached for attention, excuse the potato image quality, I cracked my phone's camera lens touring this spring

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[pmg]

Hello,

when glueing the edges to the base, underlay the wooden template and use the clamps to keep the 3 (edge, base, template) together. If you only use base and edge, there is a good change the base will warp. This could explain your problem.

Make sure you do not accidently glue the edges to the template

Best regards

[kFergie]

Oh wow I can't believe I never even thought to do that, thats a great idea! Thanks!

[mattman]

We have an edge template (base template just that little bit wider) with packing tape on the surface in case CA glue finds its way there. Also, we rabbet the bottom of the template for easier spring-clamp-usage.

[kFergie]

I tried clamping the base, edge, and template together to make it keep the straightness last night. But it didn't work, maybe a slight improvement, still probably 4 mm gaps at tip and tail.

How straight do you think I have to get the edges before gluing them on? I bend them as best as a I can, but its real hard to get it perfect, they seem to like a curve more than being straight like a splitboard inside edge needs to be

[chrismp]

You will need to keep the base clamped to the template during the whole process of attaching the edges until all edges are attached. That way the edges on both sides will keep the base from warping too much by pulling it almost equally in both directions.

This way you can even pull a slightly warped base back to its desired shape and once the edges are attached the edges will keep it from warping back.

[floydedna]

Homemade skis look very cool

[gozaimaas]

Even with perfectly straight edges before pressing my splitboards always come out with a substancial gap in the middle. I make a thin strip of wood, the same thickness as the edge and press with the strip glued in between the 2 halves, like this I get perfectly straight edges.

[chrismp]

Thanks for the tip! How do you glue the wood strip between the two halves? I always find it difficult to glue something between the halves as it's difficult to apply pressure between the halves.

[gozaimaas]

I never said it was easy lol, but it does work perfectly.
Sand down some wood the same thickness as your edge, cut a strip about 5 or 6mm wide, glue it to the edges, use tape under the base to support the glue and handle it very carefully.