kraffft work

[kraffft]

im curious where did you get all the skateboard?

Out of the boards posted, three came from a skateshop, one came from a friend, two were found in the curbside trash, two were found in a hotel dumpster, one I bought in highschool, the rest I forget.

I'm a serious junk collector, and certain parts of the U.S. are the best junk collecting spots in human history, so I had a stash saved up over the years. Donations from friends and skate shops has been the main source since I used all those.

If I were in a poorer place/time, I'd be v-lamming drinking straws and tin cans with melted plastic bags.

Krafft werk?

Kraftwerk rules.. they were way ahead of their time, made and modified a lot of their own instruments, and are all around high quality German nerds. They also inspired Afrika Bambaataa, my favorite legendary old school hip hop artist (as heard in 'Planet Rock', make sure you have a good sub-woofer to fully appreciate).

Keep the ball rolling on those wings dude!

For sure. My good friend Zach (posing with the fish tail wing above) is a real bird brain inventor type, and the main inspiration for the skate wings. We'll most likely be working on wings together for a long time.

I'll also most likely be all over the place forever.. It's been a surprise that I've stayed vaguely focused on skate related projects for this long.

What to do today?

[kraffft]

I wanted to revisit this contraption, as the main reason for making it had never been conclusively tested. That was to test the idea that the rear truck is the major cause of speed wobble.



So instead of a rear truck there's just a fixed axle, and the split deck is connected with a bicycle fork/headset (similar to a ripstik) creating no lean or turn in the back half of the board, keeping your back foot flat and solid, and giving all the ride control to your front foot.

I also really like the similarity between pivot angles on some DH and LDP setups, so it's got a (super turney) Revenge truck on the front, making it pump and turn pretty well, and pushing the speed wobble test to the limit.

The short answer is that it gets speed wobble... I'd say it's comparable stability wise to a normal deck set up with the same front truck but with a zero degree rear truck. Also I don't recommend Revenges for pumping without something extra (like Loctite) to keep the kingpin nut from coming loose.

YouTube - Rip Rocker: Pump and Bomb 9/25/09

[kraffft]

Uh.. after that, I think I'ma give up DH and stick to street skating...

YouTube - Manual Practice 9/26/09

[speshlspeclsteak]

that bike wheel thing reminds me of something i used to mess around on called a bc wheel.

YouTube - Mike Thaler BC Wheeling

it could be cool to center the wheel and have no trucks just to see how it went

[Blaise88]

Your work makes me feel all warm and fuzzy inside... such good vibes.

[kraffft]

that bike wheel thing reminds me of something i used to mess around on called a bc wheel.

My street career is takin off!!!

C YAAAAAAAAAAAAAAA!1!

YouTube - SPONSORED!

[endzone_bob]

Your work makes me feel all warm and fuzzy inside... such good vibes.

If kraffft didn't exist, we would have to invent him.

[Dancer]

If kraffft didn't exist, we would have to invent him.

Though it would be unfortunate for us, because the only person capable of inventing Kraffft would be Kraffft.

[kraffft]

Got something special for y'all today.

Axle straightening tools:

A steel rod with a 5/16" hole drilled in one end for prying axles, and two blocks to check for straightness. A vise is fairly essential. They are simple hand tools, but they take a fair amount of skill to use effectively.





The hole is drilled so the axle drops in almost all the way, leaving clearance between tool and hanger for easy bending:



Straightness checking blocks:

The idea is to have some precision blocks to roll the axle with by hand, visually checking for trueness. One with a rounded groove that the axle spins in, snugly but freely; and a flat surface to roll against.

The flat surface could use better grip, and the two blocks should have mating grooves to keep them sliding in only one line, perpendicular to the axle.

The straightening tool itself also is fairly good for checking straightness.




The video demonstrates four ways of checking axle straightness, and an exaggerated example of bending an axle:

YouTube - Axle straightening tool prototypes v1...

Straightening tool is for sale, made to order. Local pick-up only. 10$.

Straightness checking blocks need those refinements before being useful, as well as production streamlining.

This thread got me thinking about this a little while back:
Dr. Axle - how to make 'em straighter

And this one probably gave me the idea of the best way to grab the axle:
http://www.silverfishlongboarding.co...ion-axles.html

Talked with Wayne from Surf rodZ yesterday actually. Super nice, dedicated, creative, smart, and skilled guy. We might collaborate on making some glossy versions of these tools in the near future (Since they're already set up to make something very similar).

Having the hole in the straightening tool be threaded would have various advantages, but isn't necessary. One would be to guarantee that the axle threads are protected. Another would be to allow you to use two of the tool to do bending without a vise.

An interesting thing about using the tool is that you will instantly notice the difference in rigidity between various quality axles.

[speshlspeclsteak]

im gonna need one of those

[luftywaffles]

****ing awesome.

this is greatness.

[Dancer]

this is greatness.

No...

[scratch]

My street career is takin off!!!

C YAAAAAAAAAAAAAAA!1!

YouTube - SPONSORED!

we need a tenfold rep button

[kraffft]

Slide glove experiments:

"Slide gloves" are one of the aspects of longboarding that has truly limitless, largely untapped potential...

YouTube - Barbell Sliding v1 9/28/09

[pennypusher]

this thread makes me happy,you are a tad crazy but i like it.

if kenny chang says fuc#ing awesome,then it is awesome.

[kraffft]

Bladeboard:





This board was intended mainly as an exploration of a principle. I expected it to be overly exhausting to ride, which it is.

The idea originated from trying to understand pumping, and realizing that it's similar to ice skating or rollerskating/blading. Pushing the wheels to the side while they're rolling forward at an angle causing acceleration.

You can think of riding this board, or of pumping a skateboard, as putting your entire lower body in one rollerblade/skate.

If anyone knows a general term for this method of propulsion let me know.. The same thing is happening with a boat's sail, a bird's wing, or a snake's slither. Got a few more experiments coming up that are in the same realm.

You can see when I'm moving fastest in the video it looks the same as pumping a skateboard:

YouTube - Bladeboard test ride 9/29/09

Three minute mile:

This thread has gotten me thinking up lots of things:
The 3 minute mile.

So I figure I have to try it out.. It'll at least be a good way to compare various contraptions. The skate wings in particular are intended to achieve very fast times once they're refined somewhat. Heavier, larger birds fly faster. There's no need to generate lift for ground propulsion. Swans can fly 50mph (level flight with no wind).

There's a couple decently long, flat, straight, smooth roads in Providence (near water and train tracks). So I went out today and did a couple 1000 foot 'sprints' to get the feel for it and establish some rough baselines.

Measured the thousand feet with a 100' tape, chalk, and a helper. Had my helper time me with her cell phone stop watch, throwing my hands down/up at the start/finish to signal her (I'd assume the times are within 1 second accuracy, but I haven't done the course backwards yet to check for slope).

Did two runs on roller blades and one on a Sector 9 Bomb Hills with 80mm Flywheels and unwedged 45 degree Randalls, half pumping and half pushing.

Fruit boot times:

0:37.47
0:37.14

(~18mph)
(would be a 3:20 mile at that speed)

Skate time:

0:49.28

(~14mph)
(would be 4:17 mile at that speed)



(boring vid)

YouTube - 1000 foot sprints 9/29/09

[kraffft]

Made a board for the September build contest today. Full documentation to come in a day or two.

[spoctopus]

i love this thread
kraft you sir are my hero

[engebo_kelsey]

this thread is awesome. i wish i had the creativity/ingenuity that you have, Mr. Kraft.

[goldfishofhate]

you sir are a genuis