When topsheets fail.. Help solve the mystery!

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kipi
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Joined: Fri Aug 21, 2009 12:35 pm

When topsheets fail.. Help solve the mystery!

Post by kipi »

Hello skibuilders,

Today i took out my board from my vaccum press and the topsheet just peeled off. as if the epoxy didnt glue the TS what so ever..

What can be the reason????
The rest of the board seems very good...

I made some gluing test today, i will have the results tomorrow.

(and how do i upload pics O_O??)

HELP
Kipi
sammer
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Post by sammer »

Delam / not sticking could be any number of reasons.
What kind of topsheet?
Was it upside down, treated side up?

I had a base do this, still not quite sure why (could have been the acetone).

Get a photobucket account, easiest way to upload pics.

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)
kipi
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Joined: Fri Aug 21, 2009 12:35 pm

Post by kipi »

I bought the topsheet from skibuilders shop.
i already used their topsheet in my previous boards. this new one had a protective tape on one side. (the old version TS didnt) i assumed the treated side isnt the one with the tape right? if so, then it was on the right side. the one with the tape is much smoother also so i cant believe i was wrong.

I used a new epoxy for this board.. could it be the problem??
its wierd bcos i thought if the epoxy is the problem then also the base should have the same delam problem since its the same material. but the base seems to be attached very strong.
Are there known kinds of epoxys that cant stick to topsheets?

k i will upload photos to a photobucket.
i wanted to use the Image
kipi
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Joined: Fri Aug 21, 2009 12:35 pm

Post by kipi »

to be more accurate..
it did stick a lil, but i almost didnt use any power inorder to peel it off.
and another wierd thing is that the peeled topsheet have small spots of epoxy all over it. so it did stick to the topsheet but it didnt stick both layers together.
kipi
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Post by kipi »

https://docs.google.com/viewer?a=v&pid= ... yuIA&pli=1

i asked the company that sold me the epoxy to give me a specifications details about the resin. maybe it will help.
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endre
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Post by endre »

This happens with too low pressure.
solution: build a real press, use heat.
krp8128
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Post by krp8128 »

endre wrote:This happens with too low pressure.
solution: build a real press, use heat.

BS


If there is correctly mixed epoxy and a clean bondable surface you could simply lay the topsheet down and walk away for a day and you would never get it apart.

I had the vacuum fail on a pair a few years ago (before I had heat too), they topsheet is still holding strong.




Look somewhere else for the problem, my $$ is on the fact that you (should have) mixed several small batches of epoxy during the layup. The last cup (used for the topsheet) didn't get the correct ratio.
sammer
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Post by sammer »

krp8128 wrote:
endre wrote:This happens with too low pressure.
solution: build a real press, use heat.

BS


If there is correctly mixed epoxy and a clean bondable surface you could simply lay the topsheet down and walk away for a day and you would never get it apart.

I had the vacuum fail on a pair a few years ago (before I had heat too), they topsheet is still holding strong.
I have to agree with krp8128, I had a vacuum bag fail during pressing. The skis are bomber, no signs of delam after 20+ days of hard abuse.

I did have a base peel off (just like your topsheet) on my last pair.
Crown told me it was the acetone wipe. It's possible that was my issue.
Still bugging me though. I probably dded something up. Wouldn't be the first time! ;)

Maybe your epoxy had kicked.

Test all new batches before you throw away good money on ski materials.
Make a few tests and let us know what happens.
If it all sticks together, admit you probably "messed up somehow" and move on.

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)
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endre
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Post by endre »

krp8128 wrote:
endre wrote:This happens with too low pressure.
solution: build a real press, use heat.

BS


If there is correctly mixed epoxy and a clean bondable surface you could simply lay the topsheet down and walk away for a day and you would never get it apart.

I had the vacuum fail on a pair a few years ago (before I had heat too), they topsheet is still holding strong.




Look somewhere else for the problem, my $$ is on the fact that you (should have) mixed several small batches of epoxy during the layup. The last cup (used for the topsheet) didn't get the correct ratio.

BS
gladegp
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Post by gladegp »

Are you sure you didn't put the topsheet upsidedown? In that case only the protective tape sticks to the ski. I've done this mistake once and I could just peel the topsheet off.
havocdru
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Post by havocdru »

New at this snowboard/ ski thing. But I have had no problem with laminations. I've lamnated surfboards for 28 years both Poly and epoxy. With ALL delam problems I have ever had have been from unclean surfaces, aceton, finger prints, dust even. Anything that is between that lamination will cause major problems. Other thing is not a solid wet down. Clothe saturation is a must. Hope this helps.
kipi
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Joined: Fri Aug 21, 2009 12:35 pm

Post by kipi »

Ok!
I have the test results.. quite confusing i must say.

There were 2 factors that had chaged in the new board from the previous boards, the epoxy & topsheet. So thats what i checked.

The test:

4 materials-
A- old epoxy (used on previous boards, i have some leftovers)
B- old topsheet (used on previous boards, i have some leftovers)
C- new epoxy
D- new topsheet

In all combinations i did 3 layers- wood->fiberglass->topsheet. all clamped together strongly, and left for 24 hours.

The results:

A+B = super strong bond (as i expected)
A+D = no bond (wtf?)
C+B = very very weak bond
C+D = no bond

So... it seems that both new materials have a problem. the epoxy and the topsheet.
The wierd thing about the epoxy is that it looks like it has a good bond with the base, i thought bases and TS are the same.
About the topsheet... do you guys think i got a bad roll? that has some kind of a problem???
Both topsheets i have the old and the new are from skibuilders store. the old one did a great job, the new one seems bad.
The new TS has a protective tape on one side(the old one didnt have), did anyone here had a problem with this type??


[No, i didnt put it upsidedown]

What are my options now? what can i use insted of the regular TS? what materials?

tnx for all the answers^_^
kipi
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Joined: Fri Aug 21, 2009 12:35 pm

Post by kipi »

some pictures to illustrate:

Image
b4 the layup

Image
in the mold

Image
board is ready, topsheet got peeled off

Image
protective tape was on top-> topsheet on the correct side

Image
after cutting, the board without the topsheet

Image[/img]
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MontuckyMadman
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Post by MontuckyMadman »

Using a solvent on the flame treated plastic will render the bond less effective, basically negated the oxidation from the flame treating. I'm sure you would still get a mechanical bond if abraded however, I would think, maybe not.

looks to me that both the new epoxy and perhaps the new topsheet are bad or your ratios are off, may be they sent you the wrong combo of resin/hardener.
I have the flu so I have no idea.
I can't wait till I have problems like this, not really.

Your google docs link fails. You have to share it or host it open so I don't know what epoxy you are using.
kipi
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Joined: Fri Aug 21, 2009 12:35 pm

Post by kipi »

I dont know whats wrong with the google doc link, i will try to upload it again.

anyway, there is a problem with the epoxy and with the topsheet, thats for sure. it doesnt matter now.
I still need to find a solution, cos for now my board has no TS. and there are also 3 more cores waiting to get in the layup.

what are my options? i still need to make some kind of a topsheet no?...
what other materials can be used?

i sent a mail to skibuilders shop to ask if they still have the old version TS that worked fine(no answer yet T_T skibuilders managers if you see this HELP!!), if they will have it i will order some and try adding the layer to the board.
is it possible to add a TS layer to an already finished board? i will use vacum press.

ahhh
help pls
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