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Home made Boards

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Created by huddy > 9 months ago, 8 Mar 2011
Matt@DY
NSW, 51 posts
28 Mar 2011 9:14PM
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sbray said...

I had email contact with Brokite and asked them what they use for top & bottom sheets?

Their reply was:

"We use a clear vinyl material called 60/40 that is silkscreened on the down side so graphics will not wear off. It has superior UV protection and since a scratch would have to go all the way thought the 60/40 to get to the graphics, that never happens."

Does anyone have further info on this "epoxy friendly" 60/40 vinyl, e.g. Aust suppliers?

Fossil



I got some feedback from JMF on the KiteForum.com about topsheet material. PBT plastic film (which is what Brokites talk about in their video as well) is also used on snowboards and can be printed on as well.

This is a US supplier, unforetunately, who also sell inserts. I wonder if PBT is the type of material and 60/40 is a product name.

www.snowboardmaterials.com/index.php/404

Some other product names I've seen mentioned are Durasurf and Duraclear which are used the same way.

A few comments I have heard about using this or other skin material is that you need to make sure that the mold surface is free from dirt and 'specs' because although it is abbrasion resistant small grains on the surface will leave dents in the plastic and you'll loose the slick look.

The easier solution to graphics I've seen is to use an ink jet printer with rice paper for the graphics and lay it unser thin ( 1.5 oz ) glass and smooth peel ply.

Matt@DY
NSW, 51 posts
28 Mar 2011 10:12PM
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sbray said...



3. Like the look of your rocker table. What are you using as a surface?


Ta, the table is constructed from 5 full length bearers, cut to the rocker shape, then mounted on cross beams. A 6mm MDF sheet was screwed to the frame skeleton. I then glued a cheap (Bunnings) vinyl floor covering (lino) to the MDF.

The next mod was to add and seal the white "flywire framing" channel around the perimeter. I can now seal the table top using a flexible "mattress protector" rubber like sheet (from clark rubber) when I draw a vacuum via the tubes on either side.

Would I do it differently now.....YES!! the Brokite variable rocker table/clamp bed would give the ability to custom set rocker and concave easily.

The lino presents all sorts of nicks, pimples and scratches which appear on your build. In hindsight, if building a similar table, I would use laminex as a more durable surface. Haunt your local cabinet making shops for off cuts.



I built a rocker table along the lines of the Brokite table with both male and female jigs to form the mould surface and found that it was quite harder to get accurate lines than I thougt it would be

www.boardbuilders.co/2011/01/rocker-table-pt-3-construction.html

One thing I found tricky was getting the amount of concave correct. Because the top part of the table makes accessing the board a bit more difficult you end up needing more working area arond the board which means the distance from the edge of the board to the jig is larger than the distance you need if you are just using female jigs and nailing/screwing the table surface to it.

This means that to get the amount of concave accurate you need to work out how much the surface of the table will continue to curve in the space between the edge of the board and the jigs. You need to know this because you need to know how much deeper the curve in the jigs should be than the centre rockerline jig that creates the concave. I got this really wrong and ended up with half the concave I'd designed in. I later found out how to estimate it better (see link above and go to 'what went wrong'.

The tables that I have subsequently seen that look like they work well are ones that use two different surfaces. The first in usually 3/8" marine ply or MDF that is fixed at the center edges and bent up at the tips to get the right rockerline. Then a strip of, say, 5-10mm wood in placed along the long center line for about 2/3 of the length and is usually tappered off at both ends. Then a second surface (1/4" MDF, malomine coated chipbaord or masonite, laminex or perspex ) is then laid over the top of this the edges fastened at the edges to the surface below. This way you have a lot of real time control of the rocker and the concave. You can even use clamps along the edge of this to flatten the center section to get 3 stage rocker. The beauty of this is that it is adjustable real-time instead of having to cut new jigs and you can tweak it to get exactly what you want.

Fecal
VIC, 54 posts
28 Mar 2011 11:24PM
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This is a table that I built

Fully adjustable rocker and concave

Simpley loosen or tighten the nuts to get the desired rocker and concave





Matt@DY
NSW, 51 posts
29 Mar 2011 9:07AM
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Rocker tables looks great!

Few questions:

Its a bit tricky to see the details of the concave adjustors. Is there another metal bar running down the middle and the nuts sit on top of that?
What thickness MDF have you got on top?
Also, what material do you put over the top when you vacuum bag?

Cheers

Matt

suface2air
QLD, 701 posts
29 Mar 2011 6:19PM
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Ok you have a rocker table with concave in it how dose the top of board stay flat if the bottom has a concave in it . Or do ya put up with a curley top (toe to heel rocker) . I soppose the strap under pad would take care of it . Or do you machine out the bottom of the board for the rocker .

Fecal
VIC, 54 posts
29 Mar 2011 7:38PM
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The middle is the same as the out side, so in total there is three lengths of steel to adjust, the two out side ones are both set the same with the middle one set slightly higher for you concave.

The top sheet of MDF is 12ml thick

I lay my glass on top of a sheet of Perspex with mould release on top to stop the resin from sticking.

The top of the board will have a slight curve in it but with pads and straps you cant tell.

wdric
NSW, 1625 posts
7 Apr 2011 5:34PM
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Good to have a read of this stuff
Going to knock up a twin tip this weekend for a bit of racing over easter

huddy
QLD, 85 posts
8 Apr 2011 7:26PM
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100 posts. 4 pages long.

never thought this topic would make it this far.

ill actually have to finish my board now..

when the wind dies down anyway. yeoooow townsville really does blow!

theDoctor
NSW, 5765 posts
8 Apr 2011 7:36PM
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in more ways than one

Skid
QLD, 1499 posts
9 Apr 2011 12:42AM
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Copy n' paste from the BOM....

Tropical Waters, Cardwell to Bowen:
A Strong Wind Warning is current.

Friday until midnight: Winds: SE 20/30 knots. Seas: 3 metres in open waters. Swell: SE 2 metres offshore. Scattered showers.

Saturday: Winds: SE 20/30 knots. Inshore, lighter winds tending more E'ly in the afternoon. Seas: 3 metres in open waters. Swell: Se 2 metres offshore. Scattered showers.

Sunday: Winds: E/SE 20/25 knots, easing to 15/20 knots in the evening



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