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Amateur Hour
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frare bear



Joined: 01 Oct 2012
Posts: 13

PostPosted: Sat Feb 23, 2013 1:13 am    Post subject: Amateur Hour Reply with quote

Hey guys, I just pulled my second attempt at a board out of my press. For some reason, I've been determined to use a reusable vac bag to press boards... but that has turned into a huge pita.

This one seems to be pretty solid, flex turned out good, good lamination all around, edges stayed in places, sidewalls worked out. However, the top layer of glass and carbon/kevlar got all wrinkled, and the tip spacers got pushed in so they overlap the core. Not ideal, but not too serious.

I have one main question regarding some slight bubbling in the base. Does this look like a lack of pressure? too much epoxy? Waiting too long between cutting the base and pressing? And would a base grind be able to flatten it out... It's hard to tell how high the bump is, and how much it would effect the ride. Any feedback/criticism/help is welcome! This site has tons of great info and skilled builders

Bubbling:





Tip spacer overlap:



Topsheet/board shape:







Later when I get more time I'll post up more about the process and whatnot so this is more of a "journal"... I also plan to continue building, so I can post future builds here.

Thanks for any feedback!
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vinman



Joined: 09 Nov 2007
Posts: 1274
Location: The tin foil isle

PostPosted: Sat Feb 23, 2013 3:37 am    Post subject: Reply with quote

Does the bubble feel hard or hollow?

Are you using heat to cure your epoxy?

Did you tape your tip spacers in place with paper tape?

I doubt that would grind out, looks big.
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twizzstyle



Joined: 07 Mar 2006
Posts: 2196
Location: Kenmore, Wa USA

PostPosted: Sat Feb 23, 2013 9:46 am    Post subject: Reply with quote

Technically speaking you can grind until there's no ptex left. So that gives you what, 1.3mm? If the bump is any taller than that, you're hooped. And I really wouldn't be comfortable grinding away more than half of that, won't take much to get core shots.

There are a few methods for holding tip spacers in place that work well - staples outside the edges, paper tape, and medipore tape all work well.
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frare bear



Joined: 01 Oct 2012
Posts: 13

PostPosted: Sat Feb 23, 2013 9:53 am    Post subject: Reply with quote

Thanks for the quick replies, guys.

The bubble are hard, so I'm assuming filled with epoxy.

I didn't use heat blankets, but had a heater blowing warm air across the top of the board.

No paper tape.. I'll have to pick some up.

I put a scrap piece of base next to the bubble and it looks to be about the same height.... so I think this board is done for Sad

I may bring it up to the slope tomorrow in addition to my regular ride, just cause I'm super pumped to say I rode a board that I made. Might feel a little wonky but I don't think it'll de-lam or anything crazy.

Next board I should hopefully have a pneumatic press, and probably a CNC build in progress. Just started my full time job so I'll finally have some money to play with Very Happy
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knightsofnii



Joined: 08 Jan 2008
Posts: 1144
Location: NJ USA

PostPosted: Sat Feb 23, 2013 2:49 pm    Post subject: Reply with quote

there are not many bubbles that even the best of grinders can get out.

that top looks so rad, its a shame it got wrinkly.

I glue tip fill to core in spots with either hot glue gun or 2P10, or both
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vinman



Joined: 09 Nov 2007
Posts: 1274
Location: The tin foil isle

PostPosted: Sat Feb 23, 2013 3:50 pm    Post subject: Reply with quote

Can you show some close ups of your base joints? Did you cut them by hand?
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Cornice



Joined: 10 Sep 2012
Posts: 73
Location: AK TOWN

PostPosted: Sun Feb 24, 2013 12:35 am    Post subject: Reply with quote

Looks like you used packaging tape on your base? If so thats part of your problem. Ditch that stuff and your base will turn out a million times better.

Are you talking about the wave looking hump on the base?
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sammer



Joined: 19 Dec 2007
Posts: 882
Location: Fernie B.C.

PostPosted: Sun Feb 24, 2013 5:09 am    Post subject: Reply with quote

The bumps on your base had to get there after you pulled the board from the bag or it's in your mold.
What kind of mold are you using?
Show some pics of mold and vac bag system, that might help answer a few questions.

Sad to see the dollars wasted on something that won't see the snow.

Sorry to have to say this again (I've said it close to a dozen times)
Start with a simple design, base, core, glass, epoxy.
Get your process down.
Then spend the money on fancy materials and designs.

sam
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knightsofnii



Joined: 08 Jan 2008
Posts: 1144
Location: NJ USA

PostPosted: Sun Feb 24, 2013 12:16 pm    Post subject: Reply with quote

looks like the nose tail areas just didn't get proper pressure. Try prebending your core...

get a spray bottle and mist some water over the core in the tip areas, on both sides top and bottom.

Lay the core in your mold and just put a bunch of crap on top of it that's heavy, leave it like that for at least a few hrs maybe overnite.

Also any transitions where materials are butted up to each other... lets say your tip fill is more than a few thousandths thicker or thinner than your core where they mate together, that will create bubbles as well, as your pressure system will only squeeze down to the highest of the materials in that spot, and will create voids. Or if your sidewalls (if you're using them) are too much thicker or thinner than your tipfill where they meet, or your core... all these materials have to be toleranced pretty tight.
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chrismp



Joined: 13 Feb 2009
Posts: 1221
Location: Vienna, Austria

PostPosted: Sun Feb 24, 2013 11:17 pm    Post subject: Reply with quote

like knightsofnii said, this looks like a lack of pressure in the tips. i've had a similar issue on my pneumatic press...what we did was cut out the sections of the base that had bubbles and repress with new pieces of base that filled the holes. works like a charm.
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frare bear



Joined: 01 Oct 2012
Posts: 13

PostPosted: Mon Feb 25, 2013 8:55 am    Post subject: Reply with quote

knightsofnii wrote:
that top looks so rad, its a shame it got wrinkly.


Shame indeed… I have more that I’ll use for longboards and maybe another snowboard.

Vinman wrote:
Can you show some close ups of your base joints? Did you cut them by hand?


only picture I really have. Used a straight edge and razor blade to cut the overlapping joints at the same time so they would match up nicely. I did do this over a week prior to pressing, and I hear the temperature can warp it a lot if you wait.


Cornice wrote:
Looks like you used packaging tape on your base? If so thats part of your problem. Ditch that stuff and your base will turn out a million times better.

Are you talking about the wave looking hump on the base?


Yea there’s a couple small humps in the red, and a tiny bit in the white. Really? Packing tape is that bad?? What would be a good alternative? Or do you just skip it all together?

sammer wrote:
The bumps on your base had to get there after you pulled the board from the bag or it's in your mold.
What kind of mold are you using?
Show some pics of mold and vac bag system, that might help answer a few questions.

Sad to see the dollars wasted on something that won't see the snow.

Sorry to have to say this again (I've said it close to a dozen times)
Start with a simple design, base, core, glass, epoxy.
Get your process down.
Then spend the money on fancy materials and designs.

sam


I probably should have stuck with just rocker or just camber… When I get home from work I’ll post some mold pics, it’s a (fairly ghetto) wood mold.

knightsofnii wrote:
looks like the nose tail areas just didn't get proper pressure. Try prebending your core...

get a spray bottle and mist some water over the core in the tip areas, on both sides top and bottom.

Lay the core in your mold and just put a bunch of crap on top of it that's heavy, leave it like that for at least a few hrs maybe overnite.

Also any transitions where materials are butted up to each other... lets say your tip fill is more than a few thousandths thicker or thinner than your core where they mate together, that will create bubbles as well, as your pressure system will only squeeze down to the highest of the materials in that spot, and will create voids. Or if your sidewalls (if you're using them) are too much thicker or thinner than your tipfill where they meet, or your core... all these materials have to be toleranced pretty tight.


Hmm I may try to prebend it next time. If I switched to a pneumatic press that wouldn’t be an issue right? It’s just vac bags are lacking in pressure… especially since I’m over a mile high.

chrismp wrote:
like knightsofnii said, this looks like a lack of pressure in the tips. i've had a similar issue on my pneumatic press...what we did was cut out the sections of the base that had bubbles and repress with new pieces of base that filled the holes. works like a charm.


Wow, pretty cool that that works. If I still had my board I would try…. But my buddy was a complete dipshit this weekend and didn’t lock his ski rack… found all the skis (broken) but my board disappeared somehow… wtf.
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frare bear



Joined: 01 Oct 2012
Posts: 13

PostPosted: Mon Feb 25, 2013 8:57 am    Post subject: Reply with quote

Here's pics of it setup, before she went MIA



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twizzstyle



Joined: 07 Mar 2006
Posts: 2196
Location: Kenmore, Wa USA

PostPosted: Mon Feb 25, 2013 9:21 am    Post subject: Reply with quote

frare bear wrote:
Really? Packing tape is that bad?? What would be a good alternative? Or do you just skip it all together?


The packing tape didn't cause your bubbles, but it can put indentations longitudinally if the tape overlaps at all. And once you start using heat, the packing tape can melt onto your base and make a mess.

I don't put anything on my bases anymore, but it means you have a little more to grind away after pressing. If you're doing your own grinding its no big deal, if you want a shop to do it, they probably won't want to grind off epoxy.

I've also used contact paper. It's wide enough that you can do it in a single sheet, and seems to be ok with the heat? I'm not really sure. It would be better if it was a little stickier.
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vinman



Joined: 09 Nov 2007
Posts: 1274
Location: The tin foil isle

PostPosted: Mon Feb 25, 2013 2:15 pm    Post subject: Reply with quote

contact paper work great.
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knightsofnii



Joined: 08 Jan 2008
Posts: 1144
Location: NJ USA

PostPosted: Mon Feb 25, 2013 7:38 pm    Post subject: Reply with quote

you taped the entire bottom?
Just tape strips where the plastic seams are. Still a PITA to remove but less work than an entire base.
An 80 grit and autofeed makes quick work of most of it. Helps if you pick away the tape prior to grinding if possible.

We remove the tape immediately out of the press when the board is still hot, and most of the tape comes right off with fingernails and pulling it up real slow. Adn we try to get most of the residue off with acetone, then the grinder just has to remove the glue that seeped out, which still sucks but is better than trying to grind the tape away.

What about the protective clear film that some graphics people use to cover sublimated tops? Could that be used?
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