Hi all,I know this has been used for surfboards before. I would like some info on how easy it is too work with/lam? Would I need to vac bag this too work? I managed too acquire 7m of this 200g diolen & seems daft too not use it! Any feedback at all would be appreciated,many thanks. Slanj
Wet out table, and then vacuum bag. If you wet the blank, and wait for the epoxy to go to b stage, and get tacky, it works, but adds more weight than keeping all the epoxy in the cloth. Must be done with a vacuum bag, to force the cloth onto the blank.
Vacuum bag with diolen is counter productive here. Diolen is good because it thicken lam at same weight than full glass, that improve ding and buckling resistance, major cause of the ruin of surfboards, at low cost. In fact except for sandwich skin tech and some other exotic tech, vacuum bag is not really an optimize way for surfboards, but my english is too bad and i can’t write equation here to demonstrate it…
Lemat, what you are saying is that because the diolene is thicker, it is stronger. Yes, that is true. But what is your opinion of a lean lamination, holding the diolene from floating on excess epoxy? An ultra lean lamination will only adhere to the foam if pressure holds the cloth tight against the foam. Also the diolene is stronger than epoxy, so wouldn’t you be better using as much fiber and as little eopxy as possible?
Speysurfer, bagging is soooo easy! lots of threads on it, lots of you tube videos. And the equipment can be less than the cost of the materials for board you are building. Pump from a trashed refrigerator. Some hose and plastic tubing. Really makes a much better board, because it opens up more construction methods. Better set-ups can be a few hundred dollars, but the biggest cost to backyard bagging is the extra time it takes.
Great tips Everysurfer (old fridge pump,check!) I have been doing a fair bit of homework on this,as you have already said-it opens up more possibility’s. Which I’m definitely all for! Still have a few youtube clips and threads to dig through & a fair bit of extra equipment to get hold of( nae idea where im going to keep it,rapidly running out of space!) Anyhow it’s great food for my thoughts,thanks. Slanj
Thanks for the input Everysurfer,I was worried someone would tell me this! As the feel of the cloth made me think it would need to be bagged,which I have never done! I have been researching it & want to try it eventually! I don’t know nearly enough too get into a debate on which method is best. Think I’m going too have to try it both ways & decide for myself! Thanks again Everysurfer. Jings you have me thinking now! Slanj
Your franglish is fine & much better than my French! Have 2 brands of epoxy,I will check the data sheet for elasticity/flex properties. Lay on tacky lam & then laminate again as usual. Check on the dry look under glass. I hope I get the hang of it,I can get more from a friend if I want it! You have saved me from a catalouge of errors for sure. Thanks again. Slanj
I find it’s easy to work with but it’s light so it float over resin and it’s easy to use a to much resin. Lam must look dry, let it kick to tacky then lam over. It’s give a thicker lam than glass so it’s better for ding resistance and against compression, good for a surfboard
Thank you Lemat,It’s got a nice feel too it,looks a bit like carbon fibre! Should look sound under glass & like you said,good abrasion & ding resistance. It was a freebie so even better! Thanks again for the advice it is appreciated. How does it look when lammed? I think it should pop… I had a look at your sight & some really nice work Lemat,love the look of that stripey egg! Slanj.
Thanks,
Diolen look dry when is lam, the best way to hand lam it for me is like with other light fiber (kevlar or dyneema): lay them on tacky resin then lam them with fluid resin, lam must look dry, then when it’s set lam over fiberglass.
For diolen it’s better to use a quit flexible resin because diolen have an high elongation to break.
Sorry for my franglish
Sorry everysurfer but i can’t answer clearly in english.
In my work of mechanical designer and mechanical teacher i have to explain and demonstrate precisely how it works but it’s a pain in english for me.
I try : in our composit fiber take traction load transmitted by resin, and resin take all other load. Those composits have a higher strengh/weight and stiffness/weight when they have high fiber/resin ratio. Designer work when he want to use composits is to design a part where composit undergo traction. Surfboard undergo mainly flexion and local impact pressure. Surfboards are sandwich panel so when they flex they break because on skin buckle. Buckling is unstability flexural behavior of thin panel stressed in compression. With same fiber thicker resin rich panel will resist better to buckling. Impact pressure cause local flexion of skin, thicker resin rich panel are better here too. In both case you need a good resin design : a resin that have better elongation to break than fiber and idealy high resilience. + resin protect fiber against environnement, in general fibers don’t like water.
So, for me, for surfboards, higher fiber/resin ratio is not a major objective.
I follow a worked on modelisation of gluing for composits parts, they find that high pressure process gives “dry glue join” resulting in bad adhesion. Find same problem in sandwich panel where composits skin were over squezzed on core.
Sorry for my franglish
Lemat,
Two samples with identical thickness, wouldn’t the high fiber panel perform better than the low fiber panel? It seems that you are saying not. That a high resin panel works better, as long as it is the correct resin.
It depends on the nature of the efforts, the geometry of the part, and the expected behavior of the part.
For exemple i made a studdy for a racing car team : they made body parts with carbon, but they often break some. We made them with black diolen and specific flexible resin, they keep carbon look but never break them, costless near same weight.
“That a high resin panel” can “works better, as long as it is the correct resin”, against buckling. Do this test:
- sample 1 : light fiber ud by hand + hot coat +light fiber ud by hand
- sample 2 : fiber ud +resin vaccuum bag to same weight (much more fiber, much less resin)
Traction test along fiber : 2 will need a lot more force than 1 to break.
4 point flex test : 1 will be stiffer than 2 and need more force to break.
If you choose right resin you can drastically improve resilience.
Sorry for my franglish
Fit like all. Thought I would give an update of the lam with diolene cutlapped. Everysurfer I was too impatient to wait until I got all the extra equipment involved in the vac bagging process, although I have made a start on that shopping list! Lemat it went on exactly as you described. It was a lot trickier than the regular 4 or 6oz e/s cloth & did take me longer than usual, but I believe it was worth the extra time. Looking forward to finishing it up! Slanj
Lemat,
I just can’t see it.
Since the epoxy is very close in weight to the Nylon fibers. equal weight low fiber content is just as thick as high fiber content. Replacing low strength epoxy with high strength fibers will strengthen the piece.
The only way your design could be stronger pound for pound, is for the filler between layers to lighter in weight than the epoxy and fibers you are using. Perhaps an innegra fiber layer, which is lighter than others, or a foam sandwich layer between fiber layers, but not just a hot coat of epoxy. Not when weight being constant.
But nylon fiber, and other cheap plastic fiber like it, add no flexural/buckling strengh to resin, just a way to regularize thickness.
In my case my resin is specific, about half density of standard epoxy (and much tougher) so my skin are thicker. At same weight than 12oz glass/epoxy you can’t flex it with tumb test (on 2lb eps).
What epoxy are you using that is half the weight yet much tougher than other epoxy?
Which epoxy are you using, and what is the epoxy you are using as your standard to compare with?
Did not think I would stir up a hornet’s nest when I asked for this advice!! It’s an interesting topic that unfortunately I know little about. I do think that this would have been a far easier process bagging it, but alas that’s another tick on the to do list. Lemat have you come across diolene lighter than 200g? My friend cannot get any & I cant find it online, yet! Does not mean it’s not out there though! Thanks for the debate guys, it genuinely is intriguing stuff. Slanj
Speysurfer, find 200gr/m² and 300gr/m² color. But i see 164gr/m² in catalogue of swisscomposit and sicomin
Everysurfer, my resin is a epoxy base modify with a kind of urethane function, i can’t say more because i don’t really know what it is, it a proprietary product from chemist that make custom product for industry. I add some other ingredient in the sauce like foaming agent, stress spreaders etc… Mechanicaly it’s near PU RIM on some aspect.
Before i participates at the developpement of a specific epoxy resin with this company, that will be soon sell by atuacores, i use local brand from resoltech, sicomin, axson, and Resin research RR2000 CE and KK.