Twibright Bastard, an open source skateboard
- A short DIY skateboard that looks half like a streetboard and half like a
slalomboard. Can turn extremely sharp curves, easy to ride in a crowded city,
yet stable at moderate speed. Small to be taken into public transport easily.
Easy to learn pumping. However heavier than has to be due to simple material
- Weight 2064g. Comparison: Indiana Big Chief slalomboard has 2110g.
- Power jigsaw
- Electric drill
- 2 Silverspace Professional 110mm trucks or Seismic 45 deg 110mm trucks
(didn't test how stable this board is with Seismic), or at
least ordinary 110mm slalomboard trucks (with them it will be surely stable, yet not
so capable of small bends)
- 15mm x 150mm x 520mm birch (or stronger) plywood. Maple is supposedly the
best. If stronger than birch, can be 12mm.
- 3.5mm (or 2-4mm), 5.5mm (or 6mm) and 9.5mm (or bigger) drill
- 55cm black griptape
- 8 inox countersink bolts M5x30
- 8 nuts M5 inox or zinc plated
- 8 nuts M5 with plastic inlay inox or zinc plated
- 8 toothed spring washers, inox or zinc plated. Teeth pointing
inside are preferred.
- 8 washers M5 inox or zinc plated
- 8mm wrench
- Allen wrench or a screwdriver according to the bolt heads
- Paper scissors
- Carpet cutter
- Paper glue
- Hand washing brush
- Any wheels, preferrably 65mm ones
- Bearings. With rubber shields if
you can afford them. I use Bones Swiss from Skate One (former
Powell-Peralta) and am happy with them.
- bearing spacers. Make sure they have length compatible with the wheel -
seems to be 10mm for large soft wheels and 8mm for small hard ones.
- Optional: a company that makes sticky foil logos
||Print the template.
Shear the two pieces out.
Glue each template on each end of the board, so that
the half circle creates a half circular ending of the board|
|Predrill the holes with 3.5mm drill or similar, drill out with 5.5mm
and make a countersink with the 9.5mm (check with the head)|
Send this Encapsulated Postscript (EPS) to a company that makes sticky foil
logos and put the logo on the bottom of your skateboard. Don't use the
remaining formats they are incorrectly clipped because the graphics is bigger
than an A4. Please note the pictures are missing a nut and a toothed spring
washer on each bolt. What it's gonna look with the graphics:|
gonna look like without the graphics:
Assemble so that when you stand on one edge, the wheels on that edge
come together. Put washers on the bolts first. Then the plain nut and normally
tighten with a wrench and a screwdriver. Then put on the toothed washer. Then
the plastic inlay nut with the plastic facing away from the first nut. Turn
only the plastic inlay nut until the whole bolt starts to turn. Then hold down
the bolt head and tighten somewhat more than you tightened the plain nut.
|Glue the griptape on. Bend on the edges and cutt off with a carpet cutter.|
Usage for beginners
- If you don't want to risk injury, then get a bike helmet, rollerblade knee and elbow pads and gloves
with an anti-break-wrist contraption.
- The trick is that the board is self-stabilizing to the sides. If you stand there like
a dustbin and don't move your feet, if you start falling to
the side, the deck tilts and makes a curve that keeps you up there. But that
works only from some speed up (quite low for this Bastard).
- So the only thing you basically have to care about is not falling
- Easy. It's normal you feel like an idiot at the beginning. It's even normal
when you feel like an idiot after long time of learning. You don't have to
force yourself into learning. You want to learn how to use it, not how to break your
bones. You can ride wildly later.
- Using it for going to work is a painless method how to learn without losing
- To accelerate, kick back on the ground while pushing your foot forward with
- To deccelerate, kick back on the ground while pushing your foot back with
continuous force. No slipping necessary. Slipping wears down your shoes.
Usage for advanced
- The board can be accelerated without touching the ground. It's called
pumping. Wiggle your feet
to make it ride in a snake like wave. Then force the board into it's path
This way you are performing mechanical work and that has to end up in
accelerating the board. Do it with your knees bent, then you have more control
and flexibility. For a scientific description of this angular momentum transfer
mode see (1).
- It's possible to brake this way too. I have seen someone, but I didn't
yet manage to learn this :(
- Maybe there is some more advanced method how to accelerate without
touching the ground but I didn't manage to reverse
engineer that one yet ;-)
- The board is heavier than necessary. You may want to switch to a proprietary one made from
more advanced materials if you get fed up with the weight.
The trucks and
wheels are great for a professionally made board so you can keep them.
- If you think the shape is crap, tell me your suggestion how to improve it.
- Especially in the beginning, the wood can creep under the pressure and the
trucks can get loose. It's not dangerous, just annoying. In such case retighten
the jam nuts. It should eventually stop, the wood is not infinitely compressible ;-)
- If the ball bearings don't come with maintenance instructions, clean them
every time the wheels don't turn loose or make sounds. Disassemble the
bearings and wash in rubbing alcohol. If rubber alcohol isn't enough to
dissolve the dirt, use gasoline on the metal-only parts. Prevent gasoline from
coming into contact with rubber or plastic parts of the bearings! Then
re-grease with Twibright Sex
Cream, the open source skateboard lubricant.
Technical note - Jam nuts
Why did I choose jam nuts instead of the more common nut with plastic inlay?
The later nut doesn't hold on the thread enough and turns eventually loose. You
don't want to lose energy in a friction absorber created by the truck-deck
interface. The inlay nut is also specified single-use only. The jam nuts seem to be
reliable when tightened in the proper sequence.
- Jost Fetzer provided his power jigsaw for cutting out the prototype.
- Gürkan Sengün - shooting ride pictures
- John Hennessy - shooting ride pictures
- Peter Rohrer - shooting ride pictures