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| Home Made Boards (6188 Posts)
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Home Made Boards |
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A Little Advice Please
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On 8/16/2005 Character
wrote in from
United States
(67.133.nnn.nnn)
ok
i'm starting to build my own boards, but i am running into more difficulty than i thought i would. im just making boards out of plywood, and i need to know what kind of wood and what thickness is best for 28 to 40 inch boards with not too much flex, i only weigh 150 lbs. i am only 17, so i don't have access to a lot of stuff that a more experienced builder might have, like carbon fiber and stuff. i also need to know what method for bending wood would work best for making lips on my boards, is soaking effective enough, or should i build a steamer? anyway, any help you guys could give me would be greatly appreciated. you guys sound like you know what you are talking about.
thanks
-Character
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herbn
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On 8/15/2005 shapeshifter
wrote in from
United States
(198.160.nnn.nnn)
because great minds...
...get baked?
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shifting
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On 8/14/2005 herbn
wrote in from
United States
(152.163.nnn.nnn)
why was i not surprized by the peace pipe thing at the end, more than that,it was like my thoughts were prereading just ahead of where my eyes were. I've been tossing around ideas about duanes' coment on stiffer springier maple elliminating(or reducing) wobbles on a board. I'd look elsewhere for the reasons for wobble reduction, although if your birch was too soft a stiffer maple board might wobble less. But since birch ply has nicer damping action on regular flex then it would follow that it has better dampening on torsional twist. This ,i'm going to apply to a board i made recently where i routed in truck pockets to deeply, I'm going to add a layer of birch ply to the top of the board,only at the ends,just past the full cutaways i maker for wheel clearence, i'll blend these pieces in and give it a test run,or many.
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damnpening
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On 8/10/2005 shapeshifter
wrote in from
United States
(198.160.nnn.nnn)
yeah, i've been venting some of the chambers on hollow cored boards in order to provide a certain amount of dampening. otherwise there's little compression and it tends to ride like an air matteress...
...the outcome also doubles as a killer peace pipe.
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dampening
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On 8/9/2005 duane
wrote in from
United States
(68.15.nnn.nnn)
its an underestimated property. I really like birch ply for this property, it makes a very nice cruiser board for the street as vibrations are deadened very well. Not torsionally stiff enough for downhill speed, though, wobs tend to come up. When I switched over to maple, the vibration increased but wobs went away
I do think a slalom board can be too springy, it makes offsets very difficult to adjust to, or changes in cone spacing, it tends to give back exactly what you put in, forcefully, so if you get perfectly dialed in on evenly spaced cones, that's good, but hit an offset or cadence change, and you cannot adjust
seismic trucks are the same way, fun free carving but to me, trouble in changing the rhythm
a pure uni carbon spring is an incredible thing, gives back way more energy than other types (see the carbon spring pogo stick that will bounce you 5 feet). Cores, glass, and resin will add damping, the more of them the more damping, especially weaves as the weave has to straighten out before the fiber really loads up. I also think mixing fiber types leads to damping, as the fibers are loading and unloading along different curves.
I think triax glass with straight fibers feels more springy than carbon weave, so the straightening of fibers in the weave is a big deal. wish they had triax carbon, it probably exists but on a missile near you, not available
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hysteresis
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On 8/8/2005
Greg Olsen
wrote in from
Canada
(206.172.nnn.nnn)
If something moves back along the same path with a different speed(distance/time) then this is called hysteresis. The rebound speed is in the case of skateboards going to be lower due to damping losses. Damping or dampening as some call it can smooth out the rough roads and baltic birch ply is a good material to use if dampening is required. Toally foam and carbon decks are twitchy and transmit everything but also can snap back better due to less loss internally(micro friction in the wood fibres). Same in skis and snowboards. I wish there were more tech descriptions of skis out there as they have been using exotics and woods in combos for decades.
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right flex (continued)
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On 8/8/2005 p. graf
wrote in from
United States
(198.151.nnn.nnn)
Duane,
Thanks for the input. Your idea that a slalom board should just about flatten out when you stand in the middle of it sound like a good rule a thumb to me.
But you also mention "That doesn't capture the "snap" of the flex "
Are you talking about how fast the board snaps back to full camber when unweighted? Boy.. that make my head spin trying to figure that one out..
I guess I need to do some more book learning to cypher that one out!
paul
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right flex
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On 8/8/2005 duane
wrote in from
United States
(68.15.nnn.nnn)
>>>how much a board should flex under a riders weight.
for a slalom board, if the camber just about flattens out when standing still under the riders weight, that is about right. That doesn't capture the "snap" of the flex, but with all carbon you'll have plenty of that and perhaps too much
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Truck Drilling for Jake
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On 8/8/2005 Fatboy
wrote in from
United States
(67.94.nnn.nnn)
We made a template for drilling. But years ago, I used to use an old baseplate that I etched a centerline onto - worked absolutely fine!
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How stiff is stiff?
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On 8/8/2005
P. Graf
wrote in from
United States
(198.151.nnn.nnn)
OK.. This Board building thing can really become an obsession. As previously posted JBH & myself have made a couple of Carbon fiber/Foam boards with lots of help from a few generous individuals with good results. Getting the board with the desired flex or stiffness has been our main stumbling block.
I have decided to pull out my old engineering test books (mech . static’s & strength of materials.. etc) to help design a board that’s has the right amount of flex for a riders weight. This leads to the question of what is the “right amount of flex”? I know this is ultimately a personal preference, but there must be a “rule of thumb” on how much a board should flex under a riders weight.
PG
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big board
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On 8/7/2005 Matt
wrote in from
United States
(68.44.nnn.nnn)
im makin a 72 inch board thats 12 inches wide does any one kno wat material i could use other then oak...something thats lighter??
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Wood, 70's deck
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On 8/7/2005 Dave
wrote in from
United States
(67.189.nnn.nnn)
You could try 1/8" baltic birch ply.
30"x60" $11
Or just buy a new Alva or Bahne.
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maple 1/8 thick
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On 8/7/2005 Jake
wrote in from
(65.190.nnn.nnn)
try www.hardwoodstore.com I don't if they have it in stock but I think they can make it. I have seen some beautiful tigerwood there that thick. The store is located right outside Greensboro, NC 2 miles off I-85. But you can order online.
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wood for laminating your own skateboards
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On 8/6/2005
Taylor
wrote in from
United States
(64.12.nnn.nnn)
after seeing the dogtown documentary ive been in love with the small boards, trucks and wheels i saw in the movie. i looked everywere for a board but couldnt find one so i decided to make my own. ive been laminating my boards (actually only 4 so far) using 1/8" mahogany door skins. its the only wood i can find anywere thats 1/8" in thickness. the only problem is its not the strongest. i lam with multi-directional 6 oz. glass sandwiched between two layers of the door skins and 2 layers of carbon fiber on the bottom but i just broke my board due to the wood cracking. anyone have any ideas were to get the maple used for decks or anything stronger thats 1/8" thick!?!?! Any help would be awesome thanx!
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Wanna Build your dream Board?
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On 8/6/2005
Stevan L. Hemingway
wrote in from
United States
(64.12.nnn.nnn)
Got some ideas for a Ultra ride? Want it built for you? Research and development exspenses paid if you help us change the image of Gravitational Skateing in America. You dont evan have to compete with us. Just stand there and get a corp. sponser.
Mail me @ Stevan L. Hemingway
20240 Fairway DR. -OR call me @ (541) 390-8366 (c)
Bend OR, 97702 (541) 317-4701 (h)
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Hey Fatboy
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On 8/4/2005 Jake
wrote in from
(65.190.nnn.nnn)
The cherry board is going to be 4 feet but is 11 inchs wide tapered to about 8 inchs near the back truck and 7/8 thick with large cut outs. How do you drill your holes? I am just taking an old board and laying it on top and drilling before I cut out my design. Thanks
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planing foam
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On 8/4/2005 duane
wrote in from
United States
(68.15.nnn.nnn)
it is planed on the same machines as wood is... but they have to be very good machines, and blades razor sharp to work well
I don't think there would be a reliable manual way to do this. 1/4" foam is very common anyway, you should be able to find it although single sheet quantities can be trouble.
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shiny finish
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On 8/4/2005
duane
wrote in from
United States
(68.15.nnn.nnn)
there are several ways you can do this. In each case the surface the resin is in contact with must be very smooth
Roe uses a resin infusion method, whereby you vacuum down the fiber and core in the dry state, and use a low viscosity (thin) resin which is introduced through tubes. The vacuum pulls the resin throughout the structure. here you can use smooth poly film for the vacuum bag, since you never have extra resin to try to remove. Considerable experience is required to avoid doing things like sucking resin into the vacuum pump, having vacuum pinch off, or other troubles. The advantages are little wasted resin, low fumes, high fiber loadings, and great results. Even better, you suck the bag down dry, so if there are wrinkles, you can start over before resin even is introduced. Vinyl ester works very well for this.
The foam Roes do not use a topsheet, so what you are looking at is the resin itself, after the bag (or surface film) is peeled off.
If you use a topsheet, like PP does, that is made of material that sticks to the resin and remains part of the board. Shiny polyester film is ofted used. It can be printed in mutliple colors in reverse, then it becomes the surface of the board, since the film is treated to stick to resin like crazy. You can use resin infusion with topsheets but I'm not sure if PP use this technique or not. Note that on the PP I've seen the "topsheet" is the bottom, and the top is made of thin wood veneer. This is a clever way to have to deal with only one surface. Trying to get both sides of a board cosmetically perfect with fiber makes it that much tougher.
For an incredibly nice surface, if you are making something with curvature in only one direction, you can lay up fiber up against window glass, and cure it without the core. Use the bleeder and bag on the back side. When cured it will be perfect on the glass side (wax the glass!!!!). It can then be used as one side of a board lay-up, as long as curvature is in one direction only and slight (like camber would be OK, but concave more diffuclt, and not both at once). You have to be careful not to let resin sneak around the edges if you use a precured sheet like this. You can also put graphics under the fiber during the glass cure and it will come out perfectly smooth (like a recessed sticker)
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Shiny happy people?
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On 8/4/2005
JBH
wrote in from
United States
(165.134.nnn.nnn)
And as long as I'm at it: The finish on our boards has been kind of "bumpy". I think it's due to the breather/bleeder material kind of "lumping up" under vacuum. How the heck do Roe, P.Pistols, etc. get that mirror-smooth finish on their decks? On our last one, we used release fabric instead of perforated release film, and it turned out smooth but matte-finished. Looks cool in its own way, but what if I want it smooth and shiny? Anyone?
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Heh-heh...he said stiffness
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On 8/4/2005
JBH
wrote in from
United States
(165.134.nnn.nnn)
Thanks, Duane and psy..oops, I mean Mr. Shifter, sir. :-)
PG and I did think of measuring the thickness of the finished board but then forgot to do so.
Part of our problem probably stems from having to sand down our foam by hand (random orbit sander) from 3/8" thick to 1/4" thick, or as close as we could get (we did use calipers to measure the foam thickness). We got a decent supply of 3/8" foam from the manufacturer. Why 3/8" and not 1/4" or 3/16"? I don't know. I'm thinking a typo somewhere in the rep's instructions to the molder/cutter. Anyway...
Speaking of which: Can anyone recommend a cheap, reliable way to get that 3/8" foam down to a consistent 1/4" or so, so we don't have this problem with future decks?
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Jake's board
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On 8/4/2005
Fatboy
wrote in from
United States
(67.94.nnn.nnn)
Yeah! I saw that one in the picture a few weeks ago! Loooooove the sawblade look!!!
we've done a walnut, a few maple, an ash, and I'm currently ridin' a solid koa deck - 60x11" Cherry might be okay, how long are you thinking of goin'? We have some new pics up on the website in the past week or so. There will be more in the coming weeks - we're expanding the website.
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jbh's stiffness
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On 8/4/2005 duane
wrote in from
United States
(68.15.nnn.nnn)
the resin amount will alter the stiffness very little, the largest effect there is if the resin effectively makes the core thicker, in other words, spaces the carbon out from the center. A good rough approximation of relative stiffness is to cube the core thickness, so .22x.22x.22=.0106, and .25x.25x.25=.0156, so the thicker cored board will be 1.5 times stiffer. It may be interesting to measure the thickness of the entire finished board with calipers to see how much thickness the resin added, then do the math again
seems like this core difference would be a slight over- adjustment for the rider weights you listed, but not too bad. perhaps you got a soft set the second time ? that can happen if the resin doesn't kick good, try post-curing it with some mild heat but you should have done that before trying the flex, if you suspected the resin didn't quite make it.
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Hey Fatboy
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On 8/4/2005 Jake
wrote in from
(65.190.nnn.nnn)
There is a picture of my first board at downhillbillies.org on the home page. I am holding it in the group photo in the bottom left corner.
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Hey Fatboy
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On 8/3/2005
Jake
wrote in from
(65.190.nnn.nnn)
I have made one about 40 inchs that is about 8 inches wide of black walnut with about 2 inches of curly cherry on each side and it has held up great so far. I have seen hardwood boards but with stringers of different woods, which I like but you don't get to see any pretty grain. I have seen your web site but it was a while ago. I am in the process of making board 4 feet long with 4 1/2 inches of tiger wood in the center and then an inch of maple with 2 inchs of cherry on each side. I am also make one out of a solid piece of ash and one out of cherry. I just haven't seen but a couple out of one piece of wood
[no stringers] and none out of black walnut or cherry.
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messin' with resin
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On 8/3/2005 shapeshifter
wrote in from
United States
(198.160.nnn.nnn)
hey now jonathan... just as the herbinator did, i also took notice of the core size difference you had previously mentioned. my concern was depending on how you style your deck, the effect of a deeper core can be quite substantial. it is primarily at the transition point from a horizontal surface (ie: the top or bottom surface areas) changes vertical (in various degrees) to meet the opposing surface which affects stiffness most. a gradient transition eliminates some of this to a small degree. from my limited experience i would say that shape (that of the core) determines heavy in this scenario.
overloading on resin will also give you more stiffness (thick skinned) while having adverse effects on weight and invariably the skin's compressive and tensile strengths as well. from what i've read you would want about 40% resin content within your glass/carbon matrix. this is tough to determine but weighing everything before and after (including the waste material) will give you perfect 20/20 hindsight.
...hey, you know who would know more about this stuff is duane (let's see if he can chime in on this topic)!
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