Trying to build a skimboard

[Naz]

Hey guys.
Quick question. I'm trying to build my own skim for kitesurfing and just wanted to check with you whether the materials i'm about to use will work. I want to cut a board out of 2 cm (0.8inch)thick extruded polystyrene. Then, put couple layers of fiberglass cloth and epoxy to make it hard, and shape it nicely with sandpaper. Theoretically it should work, but this is the first time i'm doing this, so i'd like to know what you think about it.

Many thanks.

Naz

[tungsten]

Works well. Depending on the polystyrene you're using you might want to sand the surface to achieve a nice bond with glass (the light blue foam has to be sanded really thoroughly with 40 grit), and there are some cheapo epoxies with a lot of thinner in them which may attack the polystyrene, but normally no problemk, go for it even if the epoxy you have is cheapo, there are lots of good cheap ones. With a board like this I would use 3x 4Oz top and 2 x 4Oz bottom.

[Naz]

tungsten thanks for your response. One more question, considering that the board is almost an inch thick, how should i shape the edge? Meaning should it be V-shaped, symmetrically from top and bottom, or flat on the bottom and a bit curved on the top, like this [ ( more square, similar to nobile skimboards)?

thanks

[tungsten]

Naz, not sure if I understand exactly what you mean by that... guess you're talking about the rail? I would shape a hard rail (right angle) for good grip, and if you don't like it, you can soften it out by sanding it down; where the side wall goes into the deck, make it round so you don't hurt your shin when you're learning tricks and eat it. Long time I haven't seen a nobile skim, so dunno about those

[Slyde]

A little advice:
Polystyrene will take on water if it gets wet, so if you can try to get some divinicell or similar closed cell foam. If you cant then put xtra glass on the rails and if you get a hole seal it quickly.
I would seal the foam after shaping with a "painted on" slurry of epoxy and microfoam/ microbeads made up to a thickish consistency, then let it cure and sand off any imperfections, then laminate second, otherwise it will soak in too much epoxy when you laminate it and end up really heavy. This is not necessary with divinicell. I would try 2 layers eglass bottom and 3 top.
Try to get the shape perfect before laminating. It is a mistake to think you can sand out imperfections at the end.
Have fun!!

[Naz]

Naz, not sure if I understand exactly what you mean by that...

Sorry, that post does sound really confusing, my fault. But yes, that is exactly what i meant, what is the best way to shape the rail. I'll do it the way you said (shape a hard rail).
Now, one more thing i need to figure out, what shape should i choose for the skimboard. The thing is, that on our local spot no one owns a skimboard, so i can't build mine based on the other skimboard. I know the dimensions 52'' x20'' but not sure about the shape. I'm pretty sure that i don't want it to be fish tail. Is there any technique or maybe drawings that can help me draw the shape of my board?

Naz

[Scribble]

I made one out of pink 3/4" home depot special foam and it worked well. I put a stringer in it so I could put a little rocker in the nose and barely any in the tail. I glued the foam to the stringer with gorilla glue. The one suggestion I would have is not to paint it with just latex paint before you glass it. I had it delam on me after it's first hot day in the car. I fixed it and have not had a problem since, but I think the suggestion of the epoxy and microballoons may be a good one. I would paint it after you lam it and then put a clear coat over it or something.

For the rails I just rounded them off on top with a sureform and kept the bottom sharp. You do want to make sure you round off the bottom too on the nose and tail so you don't catch an edge.

For the lam I used 6 oz sglass which is not cheap, but very durable and I used Resin Research Epoxy with their F additive so it's pretty easy to sand compared to other epoxy resins I've worked with. For the top I think I used at least three layers of the sglass and on the bottom two. You might want to make the first one with cheaper materials because I guarantee you the next one will be better than your first.

By the way I think this is my first post, so I wanted to say thanks for the forum. Lots of good info here and no negativity. Keep it up!

Andy

[Lonny]

By the way I think this is my first post, so I wanted to say thanks for the forum. Lots of good info here and no negativity. Keep it up!

Andy

Hi Andy,

Thought I would chime into this great discussion just to add a formal welcome to LTS! Thank you also for posting your great feedback on the topic as well. Although, I have nothing to add to this great thread (especially since I could not build a skim myself to save my life )on building your own skim I will mention that it has always been my objective since I started LTS to be a positive place on the web. With great members like you and others like Naz, Tungsten, and Slyde it makes for a great place to get together and talk about strapless riding. So thank you also to all the great members here!

[tungsten]

Cheers Lonny!

Naz, RE: shape, for a first board it is a good starting point to use an approved shape. Here's a thread with heaps of shapes that work:

viewtopic.php?f=3&t=157

Pick the board you want to make your version of, get a good picture off the web and print your outline template like this

viewtopic.php?f=9&t=388 (read the first chapter, the rest is about a different building technique)

You could make your template in photoshop, but you can't tile prints in PS (at least in the version I'm running), so akushaper is easier.

If you're not sure, read up a little in the skim section and the board building section and check youtube for great board building vids.

[Naz]

Guys,
Thanks so much for your replies, got all the info i need to start building the board, really appreciate your help and friendly attitude.
I'll make sure to keep you posted on the progress and will post pics of the board when i'm done.
Again, thanks so much!!!!

Naz

[Naz]

Here comes the first problem, and i haven't even started shaping the board....
It turns out that the biggest sheet of polystyrene i can get is 47''x22'' (120x60cm), which means my skim can't be 52''x20'' as i originally planned. So my question is, if i make a board 47''x22'' (my weight is 171 lbs, 78kilo) is there any way to compensate for shorter length let's say by making the board a bit thicker (1.2'', 3cm or more) Or maybe it is possible to change the shape of the board somehow to compensate the length?
I can actually get polystyrene even thicker (2'', 5cm), but will it impact the performance?
Also, not sure whether it changes anything, but it might be worth mentioning that i'm building this board just as a beginner board, mainly for riding. I'll get myself a proper one when it will come to tricks.
Looking forward for your advice.
Many thanks
Naz

[tungsten]

Naz, 120cm is too short, the board will be one twitchy thing to ride and pearl too easily. Too fat a board is also difficult to ride. I'd take 2 sheets, put one on top of the other overlapping 30cm, cut a deep zig zag through both sheets and glue them together on a flat surface with thickened epoxy. Result is a sheet roughly 210x60cm, a good start for building your board. Stick to 52"x20".

A home grown board is a real one. It might not come out so hot in the beginning, but your 3rd board will be good and your 5th lovely.

[wile oner]

I am thinking about this also. not sure if I should start a new thread, but I'm wondering what kind of foam core you are planning to use? I know alot of people just use house insulation. Also do you use a heavier or lighter foam for kiteboardiing as opposed to traditional skimboarding?

[mattv]

If you are building a beginner board I would suggest a homemade woodie. I make wood skimboards out of 85mm think plywood and you can make any shape and size you can imagine. The process is also very quick. You can knock out a board in a day or two. I just use 3-4 coats of varnish to seal the wood and stick some kicker pads on the board. I have made about 5 boards for other kiters and have orders for 2 more. The total cost come to about $30 but I live in Japan and the materials are much more expensive here.