Full Cap Issues

[bishop119]

I have had this problem in both the pairs of skis I have made where my cap has separation in the side, basically the top layer of fiberglass and veneer isn't meeting up with the lower part and leaves an opening, ill attach a pic to show it better as im bad with words. Does anyone have an idea how to fix this in the next set, i am also thinking of doing a cap sidewall hybrid.

image1 (1).jpeg (55.35 KiB) Viewed 6265 times

Thanks,

Josh

[Thelongride]

I assume you're vacuum bagging? It's simply the vac doesn't pull hard enough to get a full wrap cap.

Going full sidewall (sandwich) or partial sidewall should solve this issue

[mammuth]

I just wonder why anyone likes to do cap top? The caps where invented for cheaper production progress, now some of the big players do advertise the special feature "sidewalls" on their top of the line skis.... Caps are pita to repair and more easily to destroy when hitting a rock...

[bishop119]

I assume you're vacuum bagging? It's simply the vac doesn't pull hard enough to get a full wrap cap.

Going full sidewall (sandwich) or partial sidewall should solve this issue

Yeah its done with a vacuum bagging, I might need to look into how to do sidewalls then.

[bishop119]

Mammuth, honestly I went with cap because it was cheaper and easier as I have just started into all this. I think sidewalls or hybrid are by far better but it seemed like one less thing to buy and figure out at the time haha.

[mammuth]

Hmm, imho cap is much more complicated and more prone to fail then proper sidewalls. The most "difficult" thing with sidewalls is to find a router with tilt base or an angled bit.

Where is the difference with needed material? Or are you just using a core without sidewall at all to do your cap ski? If so, yes you dont need some abs or urethane. But an impact would be even more devastating cause you have no impact zone (which is the dampening zone by abs/urethane or a hard zone if you use some hard wood as sidewall)

[mammuth]

Yeah its done with a vacuum bagging, I might need to look into how to do sidewalls then.

Absolutely no difference! Same process. It helps when you do your blank a little bit wider then just the edge, same width like the raw topsheet. Like this you dont create a kink with your topsheet where resin and air could be trapped

[Cadman]

One of the big problems with vacuum bagging is getting enough pressure. Especially on steep sidewalls. 45degree is about max before you starTto have issues on caps when vacuum bagging.

[bishop119]

Hmm, imho cap is much more complicated and more prone to fail then proper sidewalls. The most "difficult" thing with sidewalls is to find a router with tilt base or an angled bit.

Where is the difference with needed material? Or are you just using a core without sidewall at all to do your cap ski? If so, yes you dont need some abs or urethane. But an impact would be even more devastating cause you have no impact zone (which is the dampening zone by abs/urethane or a hard zone if you use some hard wood as sidewall)

Yup no sidewall just the fiberglass and veneer protecting the ski. my only hesitation would be sidewall material from crown is $160 (which yeah comes with a bit of material) but its a little steep for right now (i need to buy more expoxy and edge stock first). I also noticed in my last ski the cap did come down the whole way in some spots so im really not sure where the issue is.

Also when you talk about a blank do you mean making the core/sidewall part bigger than the base/edge width so there is room to trim down?

[JSquare]

Yup no sidewall just the fiberglass and veneer protecting the ski. my only hesitation would be sidewall material from crown is $160 (which yeah comes with a bit of material) but its a little steep for right now (i need to buy more expoxy and edge stock first). I also noticed in my last ski the cap did come down the whole way in some spots so im really not sure where the issue is.

Also when you talk about a blank do you mean making the core/sidewall part bigger than the base/edge width so there is room to trim down?

If you're just getting up and going-- wooden sidewalls are fine. Wood offers some advantages too-- better/easier bonding, cost, and more pop (higher modulus). Some of the more exotic skis use exotic woods-- but those can get expensive and can have bonding issues depending on the species (and for me there's the matter of generally avoiding rainforest woods in my projects).

Plenty of threads on this here. I used cherry for a few sidewalls early on and never had any issues with damage/ingress. I did cedar once-- which is a great wood for outdoor stuff but just split/cracked. I think the general rule would be to use woods people use for cutting boards (closed pore, tough, cheap, easy to glue)-- maple, birch, cherry, come to mind. You can seal them with paint or just oil them a couple times a season.

[mammuth]

Also when you talk about a blank do you mean making the core/sidewall part bigger than the base/edge width so there is room to trim down?

Yes, you glue the sidewall to the core and some wood outside to the sidewall. The outside wood just acts as a spacer, so take whatever you have laying around and which is not usable for the core

Looks then similar to the cores the guys who use urethane for sidewalls (they make a channel for the urethane)

p.s. The term blank is coming from the surfboard "cores"

[JSquare]

Also when you talk about a blank do you mean making the core/sidewall part bigger than the base/edge width so there is room to trim down?

Yes, you glue the sidewall to the core and some wood outside to the sidewall. The outside wood just acts as a spacer, so take whatever you have laying around and which is not usable for the core

Looks then similar to the cores the guys who use urethane for sidewalls (they make a channel for the urethane)

p.s. The term blank is coming from the surfboard "cores"

With the main site down, we really need a sticky for the top of this thread to folks external resources that can square people away.
http://www.happymonkeysnowboards.com/Mo ... _sidewalls

[mammuth]

Yes, as sticky sections of howtos would help a lot. Otherwise it will become facebookish here ... ask before search

[bishop119]

Thanks for all the info, I will definitely look into wood sidewalls as a backup option to the PTEX. Monkey Wiki always makes me wish I had a better shop space and a CNC.

[JSquare]

Yes, as sticky sections of howtos would help a lot. Otherwise it will become facebookish here ... ask before search

I almost answered a technical question on the facebook snowboardbuilders group today... then i thought.. naw... this is a pain. They can do their homework, think, and then come find us on the skibuilders forum