*


All times are UTC + 1 hour



Post new topic Reply to topic
 [ 17 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Shinny top & dirty plexiglass on rocker table
PostPosted: Wed Jun 12, 2013 9:01 pm 
Offline
Rare Poster

Joined: Thu Mar 15, 2012 7:32 pm
Posts: 38
Hey guys, two questions following the completion of my first foam vacuum bag kiteboard:

First, how can I obtain that shinny look on top of my board as mine is not shinny at all. I used standard 3 layers of fiberglass cloth on top of my cotton with peel ply and breather but the final look is not shinny. It's not an issue to ride the board but doesn't look like ones I've seen on the forum from board builders...

Second, how can I clean my plexiglass for my next board as there is a bit of epoxy left and some marks from my board in there? I didn't use mold release as my partner was suppose to have some but it turns out he didn't... I was surprised that the board wasn't hard to peel off from the plexyglass but now I need advises in order to be able to use it over and over again, with mold release if needed!!!

Thanks for your help.

P.S. Pictures to follow once I finish exposing the rails NLT this week-end ;-)


{ SHARE_ON_FACEBOOK } { SHARE_ON_TWITTER } { SHARE_ON_ORKUT } { SHARE_ON_DIGG } { SHARE_ON_MYSPACE } { SHARE_ON_DELICIOUS }
Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Thu Jun 13, 2013 3:07 am 
Offline
Medium Poster

Joined: Fri Apr 06, 2012 2:01 pm
Posts: 135
cant tel about the plaxy but :

the gloos finish you dont have is because u used peel ply and breather.
there wont be any gloss finish IF you use a plastic sheet that has holes in it ( to let resin get to the breather ).

glossy finish and breather dont work !

or am i wrong ?


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Thu Jun 13, 2013 7:14 am 
Offline
Very Frequent Poster

Joined: Thu Feb 20, 2003 7:14 pm
Posts: 583
Short of using pre-cured top and bottom sheets in a press, or using some kind of mould in a press, my experience has been that the only way to consistently get a perfectly smooth finish without excess resin weight is to apply fill coats and learn how to sand.

Once you learn how to sand, you can consider learning how to polish or how to apply a nice finish coating such as paint or clear coat.

Other methods tend to yield either heavy or very amateurish looking results at best.

Trent


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Thu Jun 13, 2013 10:50 am 
Offline
Frequent Poster
User avatar

Joined: Tue Feb 24, 2009 1:43 pm
Posts: 322
Location: Iv.G.-Slovenia
I did pre-cured top sheets with 2 glass sheets on PVC sheet (you get the shinny finish) the other side (which comes bonded with core) had peelply and breather. You must sand the grain left from the peelply.
I also did it with TPU top sheet.
In both cases I get a lot of air traped in the middle, and this pisses me of!

Cleaning the plexi could be done bi simply scraping it with a spatula. However if the plexi is scratched, the epoxy will stick more.


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Thu Jun 13, 2013 11:48 am 
Offline
Frequent Poster
User avatar

Joined: Tue Jan 02, 2007 11:50 pm
Posts: 272
Location: Ottawa, Canada
Hey Dany, I think if you use peel ply you will always have a dull and slightly rough finish. Yes, you get good excess resin removal, but then you have to add more resin after to get it smooth, and sand and polish. If you go with the method of vinyl on top of the glass and cotton, and squeegee as much excess out as you can once the vinyl is on top, you will get a pretty smooth and shiney finish. I'd be surprised if you could tell the difference in board weight, and there's no risk of sanding into the fibers and weakening it. (the vinyl method is what I use in my youtube video, but I can't claim to be the inventor of that)

As for the plexi, yes, you can scrape it with something plastic, like maybe try the edge of an old credit card. From what I hear, some epoxy will not bond well to plexiglass and other stuff will, depending on how they treat the surface of the plexiglass when they make it. On other plexiglass types, epoxy might bond too well making it tough to pull off the board. You may find that future jobs on the same plexiglass begin to bond better and better, and it will then get harder and harder to clean the plexi without scratching it, so you might want to use some release for future boards. If you're up this way I can set you up with some.

(edit) - I should also add that yes, sanding and painting CAN look very professional, but it can also look awful if not done well. For most of us, I think you can get as good or better finish results without nearly as much effort using vinyl over the glass as the top half of the bag. A cotton topsheet compared to pigment adds 100 to 150 grams. Not sure how much paint weighs, but it's not a huge weight saving.

Peter


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Thu Jun 13, 2013 8:38 pm 
Offline
Rare Poster

Joined: Thu Mar 15, 2012 7:32 pm
Posts: 38
Peter, I surely watch your youtube videos online several time and it indeed ease the production of my first board... Please correct me if I'm wrong but the vinyl technique is to apply it on top of the fiberglass & cotton, make sure to squeeze as much epoxy and air bubbles and proceed with the vacuum bagging directly from the vinyl?!? What about all the excess epoxy and is this technique an issue if the whole board is made out of one single step (instead of two different steps, one for the bottom and one for the top part)???

I found that there is enough sanding already and I'm not planning to do some more so the vinyl option sound like the best option!!!

P.S Can't refuse the mold release offer and should be around CB when good wind will be blowing from the right direction (and preferably on a weekend ;-))

Thanks


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Thu Jun 13, 2013 9:01 pm 
Offline
Frequent Poster
User avatar

Joined: Thu Oct 18, 2007 7:30 pm
Posts: 482
Location: Denmark, Frederiksværk
foam-n-fibre wrote:
Hey Dany, I think if you use peel ply you will always have a dull and slightly rough finish. Yes, you get good excess resin removal, but then you have to add more resin after to get it smooth, and sand and polish. If you go with the method of vinyl on top of the glass and cotton, and squeegee as much excess out as you can once the vinyl is on top, you will get a pretty smooth and shiney finish. I'd be surprised if you could tell the difference in board weight, and there's no risk of sanding into the fibers and weakening it. (the vinyl method is what I use in my youtube video, but I can't claim to be the inventor of that)

As for the plexi, yes, you can scrape it with something plastic, like maybe try the edge of an old credit card. From what I hear, some epoxy will not bond well to plexiglass and other stuff will, depending on how they treat the surface of the plexiglass when they make it. On other plexiglass types, epoxy might bond too well making it tough to pull off the board. You may find that future jobs on the same plexiglass begin to bond better and better, and it will then get harder and harder to clean the plexi without scratching it, so you might want to use some release for future boards. If you're up this way I can set you up with some.

(edit) - I should also add that yes, sanding and painting CAN look very professional, but it can also look awful if not done well. For most of us, I think you can get as good or better finish results without nearly as much effort using vinyl over the glass as the top half of the bag. A cotton topsheet compared to pigment adds 100 to 150 grams. Not sure how much paint weighs, but it's not a huge weight saving.

Peter


Hi, can you throw a link to those videos?


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Fri Jun 14, 2013 12:30 am 
Offline
Rare Poster

Joined: Thu Mar 15, 2012 7:32 pm
Posts: 38
I don't know how from my IPhone but try this on youtube:

"How to Build a Kiteboard Part 1of 3"

There are three videos and the author/actor (;-)) is "Foamnfibr"

Cheers


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Fri Jun 14, 2013 3:31 am 
Offline
Frequent Poster
User avatar

Joined: Tue Jan 02, 2007 11:50 pm
Posts: 272
Location: Ottawa, Canada
Here's the link to the first video, http://www.youtube.com/watch?v=d5NNDktWgn4 glassing is in part 3. This was from the days of 10 minute limits on youtube!

Glassing it is here http://www.youtube.com/watch?v=QwKzI-oIC_o

You'll notice around 4 to 6 minutes of the glassing video that the vinyl is all they gets put on top of the board. I guess I didn't make that clear. The vinyl gets all smoothed out, and you can keep pulling out extra resin after the vac is on. The vinyl gets sealed to the tape around the plexi and the vac gets turns on. There's no other "bag" on top of the vinyl.

I've only ever done this with a 2 step process. With the vinyl on top not allowing air to travel out from the bag, I don't think this would work very well with a one shot process, since the only way for air to get out would be to move out to the edges. That can be done with a squegee on the top, but you have no way of letting air out of the bottom. Or maybe someone tried and it was OK? I haven't been brave enough to try one shot with this, since I have my doubts.

Peter


Top
Profile
 Post subject: Re: Shinny top & dirty plexiglass on rocker table
PostPosted: Thu Jun 20, 2013 8:18 pm 
Offline
Rare Poster

Joined: Thu Mar 15, 2012 7:32 pm
Posts: 38
Peter, everything is clear in your videos is just that for a newbie that never played with époxy and vacuum bagging before, it's a lot of info in a short period of time...

As promised, find attached pictures of my first board for which is based on my Cabrinha custom 135 (2010 if I am not mistaken but time goes by too fast for me to remember exactly which year exaclty is the model I have ;-))...

If you look carefully, you will notice, on the bottom of it, that the fiberglass cloth is visible and I was wondering if it was because too little epoxy was used or because the plexiglass was not 100% smooth (the previous owner did at least a board with it and there was some residue that I didn't removed prior to vacuum bagging mine...). Any words of wisdom on this?!?

Also, there is some corecell that is visible on the bottom left along the rail but that's another story (as I cut my fiberglass cloth too close of the board and the corecell probably moved during the process and/or when I started to vacuum bag the board...)

Finally, the board is way too flex (like foam-n-fibre warned me...) and it is also surprisingly light (don't have a balance to weight it accurately but it is very light, way more than my Cabrinha Custom... I used T600 10.5 mm corecell, only tapered the tips to approx 6 mm and put 3 layers of e-glass on each side but it is quite flex in the middle of the board. What is the best way to get one more stiff??? Should I use Kevlar and/or more fiberglass cloth, a wood core, or anything else... Keep in mind, if you have any suggestion, that I am on a budget given the fact that I have access to fiberglass cloth and kevlar for free so number of layer doesn't matter even though total weight does matter... I honestly don't know what to do here...

P.S. I will let you know once I tried it on water but compared to my other Cabrinha boards (Custom, Rival and Caliber) I bought, it seems way too flex for kiteboading...

Dany


Attachments:
P6200550.JPG
P6200550.JPG [ 5.28 MIB | Viewed 1304 times ]
P6200549.JPG
P6200549.JPG [ 5.32 MIB | Viewed 1304 times ]
Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic
 [ 17 posts ]  Go to page 1, 2  Next

All times are UTC + 1 hour


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group