After 1 year lurking in this forum, I have finally started truly working! I am relatively advanced in my construction, as all my materials were ready, and was about to profile my cores tomorrow.
The only problem being that my bases seemed to have rounded. Now, when I place my shaped cores on the bases and adjust the tip and middle parts, I get a full edge width (including its teeth) space between the side of the core and the side of the edge. And approximately the same difference on the other side, and this for both of my pairs. I have tried every possible movement I could think of to see if it was better, but it was always more or less the same thing. It is strange because I used the same shape mold for my cores and bases, only adding materials for the core. Maybe they have distorted during edge placement (3/4 edge-wrap), since I put on edge after the other.
Do you think it is possible in any way to save those bases or do you think I should get new materials and start all over again?
Max skis (need help :P)
Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp
One edge at a time is not ideal that's for sure.
How long has it been since you cut the base material ? Temperature in Quebec has been fluctuating a lot this last week, is your shop is not at a constant temperature it might also have quite an impact. I usually cut the base and glue the edges minutes bore I start the layup, I don't even let it sit overnight.
How long has it been since you cut the base material ? Temperature in Quebec has been fluctuating a lot this last week, is your shop is not at a constant temperature it might also have quite an impact. I usually cut the base and glue the edges minutes bore I start the layup, I don't even let it sit overnight.
A bad day skiing is always better than a good one at work...
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skidesmond
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Post pics if you can.
So what do you think warped the bases or the cores? I had a similar problem. Mine was the bases. After I routed my bases I made sure they were the same by placing them together to be sure they had the same shape. Then flipped one over and matched the bases again and they should match exactly. Any difference s/b fixed at this point before going any further. Could be the template is not symmetrical or the base moved slightly when cutting it out.
Assuming no problems at this point, the edges go on. Once they are on match the bases again as before. I did not do this before on a few builds and it caused a similar problem I think you are describing. I was only bending the tip (3/4 wrap) and the tail. I didn't think the middle part of the edge needed any pre-bending. However it seems that fact I didn't pre-bend the middle caused some tension in the middle on the base and both bases ended up being off by a good 2+ mm in the same spot. I actually saw this happen on my last pair. I was able to peel the edges of, luckily, w/ a razor blade. Be careful trying to pry them off. I pre-bent the edges and re-glued them on the base. This time they match up perfectly.
A lot of people don't pre-bend for the entire length of the ski and have no problems. I'm wondering if I had a problem because my skis generally have a large side cut.
Since you shaped the cores check the cores w/ each other, same as with the bases. It possible the cores have warped or twisted depending on many factors.... moisture, type of wood. Wood w/ a tight vertical grain has less movement.
I hope this helps. Let us know what it turns out to be.
So what do you think warped the bases or the cores? I had a similar problem. Mine was the bases. After I routed my bases I made sure they were the same by placing them together to be sure they had the same shape. Then flipped one over and matched the bases again and they should match exactly. Any difference s/b fixed at this point before going any further. Could be the template is not symmetrical or the base moved slightly when cutting it out.
Assuming no problems at this point, the edges go on. Once they are on match the bases again as before. I did not do this before on a few builds and it caused a similar problem I think you are describing. I was only bending the tip (3/4 wrap) and the tail. I didn't think the middle part of the edge needed any pre-bending. However it seems that fact I didn't pre-bend the middle caused some tension in the middle on the base and both bases ended up being off by a good 2+ mm in the same spot. I actually saw this happen on my last pair. I was able to peel the edges of, luckily, w/ a razor blade. Be careful trying to pry them off. I pre-bent the edges and re-glued them on the base. This time they match up perfectly.
A lot of people don't pre-bend for the entire length of the ski and have no problems. I'm wondering if I had a problem because my skis generally have a large side cut.
Since you shaped the cores check the cores w/ each other, same as with the bases. It possible the cores have warped or twisted depending on many factors.... moisture, type of wood. Wood w/ a tight vertical grain has less movement.
I hope this helps. Let us know what it turns out to be.
Both bases fit perfectly one on the other, but when I turn one around, there is a difference of about 1 cm, while the cores fit almost perfectly on each other, independently of the sense I put them (as they are symmetrical).
I just finished tearing up the edge with an exacto. I also confirmed that my Lepage Super Glue really works! I will see if my base will straigten overnight, clamping it to help it a bit. There is still the same curve in the bases, which doesn't appear on the cores, even though it was built with the same mold. I'll try re-glueing the edge tommorrow, if the bases are better.
I just finished tearing up the edge with an exacto. I also confirmed that my Lepage Super Glue really works! I will see if my base will straigten overnight, clamping it to help it a bit. There is still the same curve in the bases, which doesn't appear on the cores, even though it was built with the same mold. I'll try re-glueing the edge tommorrow, if the bases are better.
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skidesmond
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They bases should fit perfectly (or with in a hair or 2) both ways. That way you know your bases are symmetrical. If they are not then you can try to re-shape them, maybe when they relax they'll match up better. But I would check your template.
Trace you template on a work table. Then flip your template over. It should match the tracing. If it's off by a cm or so then the template is your problem.
Also the p-tex could have relaxed out-of-shape after you cut it. It's been known to happen. I'd let the base sit by themselves w/o clamping and see what happens.
Bottom line is the bases need to be as symmetrical as possible.
Trace you template on a work table. Then flip your template over. It should match the tracing. If it's off by a cm or so then the template is your problem.
Also the p-tex could have relaxed out-of-shape after you cut it. It's been known to happen. I'd let the base sit by themselves w/o clamping and see what happens.
Bottom line is the bases need to be as symmetrical as possible.
It's amazing how much temperature affects your base material.
You can make it warp just placing you hand on it for a few moments.
But it really sounds like your template is not symmetrical.
If you printed out a snowcad template and traced it that would do it.
Probably 70% on the templates I've printed are off.
I'll glue the paper to a 1/4" piece of paneling then pick the side cut-edge I like best,
screw it ( pattern) to a piece of MDF and trace the one side with my router.
Then flip the pattern over, use the same screw holes and trace that with the router.
Even that doesn't always result in a perfectly symmetrical template, but they are darn close
And like Ben I always cut out my base minutes before layup.
Gluing on edges, I'll glue a couple tangs on 1 side then a couple on the other working my way from tip to tail.
Hope this makes sense and that it helps.
sam
You can make it warp just placing you hand on it for a few moments.
But it really sounds like your template is not symmetrical.
If you printed out a snowcad template and traced it that would do it.
Probably 70% on the templates I've printed are off.
I'll glue the paper to a 1/4" piece of paneling then pick the side cut-edge I like best,
screw it ( pattern) to a piece of MDF and trace the one side with my router.
Then flip the pattern over, use the same screw holes and trace that with the router.
Even that doesn't always result in a perfectly symmetrical template, but they are darn close
And like Ben I always cut out my base minutes before layup.
Gluing on edges, I'll glue a couple tangs on 1 side then a couple on the other working my way from tip to tail.
Hope this makes sense and that it helps.
sam
You don't even have a legit signature, nothing to reveal who you are and what you do...
Best of luck to you. (uneva)
Best of luck to you. (uneva)
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doughboyshredder
- Posts: 1354
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for some reason this is never much of an issue for snowboards, or at least it hasn't been an issue for me. (knock on something).
Good reason for having a cassette though. I would think with a cassette with the shape copied in to it (like richuks) you wouldn't need to worry about this, as the base would expand back to it's original shape under pressure and heat? If heat affects it as much as sammer says, I am curious if any of you guys building skis had checked your final ski versus your template to see how much the shape has changed after pressing.
Also, this is another reason why there should be no tension on your edges after bending them.
Good reason for having a cassette though. I would think with a cassette with the shape copied in to it (like richuks) you wouldn't need to worry about this, as the base would expand back to it's original shape under pressure and heat? If heat affects it as much as sammer says, I am curious if any of you guys building skis had checked your final ski versus your template to see how much the shape has changed after pressing.
Also, this is another reason why there should be no tension on your edges after bending them.
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skidesmond
- Posts: 2337
- Joined: Tue Apr 07, 2009 3:26 pm
- Location: Western Mass, USA
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Good point about Snow_CADX. I found the same problem with printing and taping the paper. I send a full size pdf file to Staples and they print it for me, $3-$4. Your method also works.sammer wrote:...
If you printed out a snowcad template and traced it that would do it.
Probably 70% on the templates I've printed are off.
I'll glue the paper to a 1/4" piece of paneling then pick the side cut-edge I like best,
screw it ( pattern) to a piece of MDF and trace the one side with my router.
Then flip the pattern over, use the same screw holes and trace that with the router.
Even that doesn't always result in a perfectly symmetrical template, but they are darn close
And like Ben I always cut out my base minutes before layup.
Gluing on edges, I'll glue a couple tangs on 1 side then a couple on the other working my way from tip to tail.
Hope this makes sense and that it helps.
sam
The last 4 templates I made I trued them up by tracing onto 1/4 hardboard like Sammer mentioned.
I initially found minimal variation until my template went sour. Edges were noted as being a bit wavy - by critical ski tech. Nothing that wasn't easily dealt with.
DBS - accuracy is now more important, otherwise tensions within the mould become an issue when loading the various bits and pieces ... to be honest, its still a work in progress.
DBS - accuracy is now more important, otherwise tensions within the mould become an issue when loading the various bits and pieces ... to be honest, its still a work in progress.
Just checked the template, and it is perfectly symetrical.Furthermore, I cut the cores on the same template, adding materials to match for the edge width, and they are perfectly symmetrical. The bases still have a nasty curve in them, so I will just cut another pair of bases, using its matching core as a template, with my router. I will then take off the width of the edge with an exacto, and I will wait before glueing the edges to ensure the base don't wrap again. And the bases will be stored in the basement, to minimize the temperature variation.
My .02
clamp the base to the template
Cut / route the pattern for the base
Leave the base clamped to the template
Attach edges
Start at one end and work your way to the other glueing both sides as you go
Once edges are glued, remove the base from the template
Start over with other ski.
Works fine and keeps the base from moving / warping.
I would not cut the base and let it sit prior to edge attachment. Had this happen in the past (distant past) and had to use the wife's hair dryer to get the base to move into the desired shape.
Good luck,
ra
clamp the base to the template
Cut / route the pattern for the base
Leave the base clamped to the template
Attach edges
Start at one end and work your way to the other glueing both sides as you go
Once edges are glued, remove the base from the template
Start over with other ski.
Works fine and keeps the base from moving / warping.
I would not cut the base and let it sit prior to edge attachment. Had this happen in the past (distant past) and had to use the wife's hair dryer to get the base to move into the desired shape.
Good luck,
ra
sorry guys, but i do doubt theese "magical" deformations that hapen to p-tex. first of all. its made to be in fluctuating tempatures. imagine how many times you wax your skis before going to ski. i dont know where you people live. but here in canada, irons are hot. and snow is cold.
btw,
i routed 4001 electra base in + 18 degrees ( celcius ) and left them over night in 2 degrees. and them compared to my template. no difference.
btw,
i routed 4001 electra base in + 18 degrees ( celcius ) and left them over night in 2 degrees. and them compared to my template. no difference.