kraffft work

[Barf]

those two wheels just have a harder duro for the core, which isn't really different then pretty much any longboard wheel.

Nah, take another look, especially at the Autobahns. Most longboard wheels have a really, really hard core, something measured on the Shore D scale. Then the rest of the wheel is poured around that. These are one solid chunk of urethane, poured all at once, and the core's only slightly harder. Also, I'm pretty sure I read somewhere else that the softer outer section's only a few mm thick- the theory being that it'll give better grip while still not deforming and eating up speed in the process.

I can't tell if you meant discs of different hardness sandwiched together, so the rolling surface would have stripes of different material, or a hard core with soft rolling surface (which has clearly been done, as pointed out by Barf and SD974).

Also been done. Pics coming, But wait!

-Wheels with removable urethane outer rolling surface.. so when you get a flat spot, or bad coning, you can just put a new outer layer on, instead of replacing the entire wheel. (There's a good trick, used in a lot of situations where a very tight fit is needed, where you cool the inner part to shrink it and heat the other part, so they assemble easily, but when they reach the same temperature become basically fused..)

I can kill both those birds with one stone. Welcome to the 1970's, I give you the Fanjet:







Note the colored bands on the tires at the backside of the hub- yup, that's a different durometer pour you're seeing. And check the circlips on the back of the wheels- pull them off, pull the hubs out, and put new tires on. The ones in the pics were really rollerskate tires, but they made skateboard tires for the Fanjet hubs, too:

[Snow]

Sooo first of all I'd like to say I love your thread, you have some crazy/amazing ideas going on =]
I want some of those slide wheels lol.

today though, my art teacher had a lecture about this book he wrote on creative reuse: http://ibreakplates.com/wp-content/u...1592535408.jpg

and one artist shown in it reminded me a lot of the stuff that you do. Not sure if this has been mentioned before, and not trying to offend or anything if it does, it just came up and it instantly reminded me of some of the stuff here.

The Scooter Wood Bike

[kraffft]

And check the circlips on the back of the wheels- pull them off, pull the hubs out, and put new tires on. The ones in the pics were really rollerskate tires, but they made skateboard tires for the Fanjet hubs, too:

Fixed that last image for you. It really shows the 'circlip' well.

That is some really great info.. and part of what makes the fish truly great.. so many people with first hand experience of the entire history of skateboarding! I'm always interested to see anything similar to what I'm doing.. as well as any criticisms or feedback. I know it can feel like a bummer to break the news to someone that their idea/project has been done before.. but it won't bum me out at all. Especially with the more similar things I'd love to try to track down the person that did it.

Another reason it's good to hear about similar things (especially in the level of detail that Barf just shared) is that it will give me/others more ideas.

I'm thinking of scrapping the press fit approach for that retread wheel idea, and going with a split hub (similar to a mountain board wheel). Here's a crude 3D model of what I'm thinking:

(gotta get some practice at that- it took me longer to draw than it would have to make a prototype).

The two different green colors represent urethane, and the orange is a core. The idea is to have the replaceable part be as thin as possible, but to still have as much urethane depth as you want.

Then you could also switch between all kinds of duro, reflex, and slide properties on the outer layer.

And there's plenty more nice things you can do once you have a hub that's intended to last a while. Precision aluminum hubs (similar to the Fanjets). More sophisticated bearing systems.. Ultra-lightweight materials..

As is true of any ideas I post here.. this is free for the taking. I'm not actually about to try to start mass producing these myself.

[dunnersboarder]

dude your a fking genius! oh and with your crazy ideas for slide gloves: i think ive only seen them on new zealand web sites but its these slide gloves that sort of use really small wheels imbeded in the glove which obviously roll rather then slide. like sepherical bearings or something. oh well yea i sould love to see u make some of them.

[chees-]

dude your a fking genius! oh and with your crazy ideas for slide gloves: i think ive only seen them on new zealand web sites but its these slide gloves that sort of use really small wheels imbeded in the glove which obviously roll rather then slide. like sepherical bearings or something. oh well yea i sould love to see u make some of them.

those gloves apparently suck i think they have been discussed before?
that wheel looks sick make some

[goldfishofhate]

Magnum Skateboard Wheels by Grand Prix Skateboards



simpsons did it

[chees-]

Magnum Skateboard Wheels by Grand Prix Skateboards



simpsons did it

ok maybe you could make the split duro but better as in the sandwiched type, inner half of it harder for speed then the outer half softer to grip round corners would this work??????

[Ogre]

Like deez?





Rough specs on the two different designs:
-Single fin: <3 lbs, ~12sqft surface area.
-Wings: <1lb each, ~9sqft total surface area.

Leonardo was your mentor..no?

[kraffft]

UHMW blades

It's like ice skating, except the steel is plastic and the ice is pavement.



This was primarily a material test, to see how much grip a square edge of UHMW would have against pavement.

YouTube - Plastic blade skating on pavement

Less than I'd hoped.. but still a lot of potential. Slides dramatically differently on different surfaces.. rough pavement working the best.

Here's the wear after about an hour of messing around:

You can deliberately reshape the blade to some extent depending on how you skate.. that mushrooming is from sliding straight without much pushing off the edge.

Need to try narrower blades next to see how much it improves the slide distance (and reduces durability).

A quick project I did ~9 years ago.. ice running boots.. putting steel teeth on the toe of a boot, so standing flat the teeth wouldn't touch the ice, but pushing off with the ball of your foot, the teeth would bite and give you traction, allowing you to run and slide. Something like that could work easily with the UHMW on pavement, but I'm definitely going to keep an eye out for some other material (various engineered plastics?) that'll work better as a pavement ice skate.

That, and I have to try just using regular ice skates on pavement.


3 Minute Mile:

I've been considering this too boring to post daily updates about, but I've been trying to do one time trial a day. Most of the runs to date have been gathering baseline times for comparison to weirder boards. These are my fastest times for various boards and other transportation:

Bicycle_________________________3:01____19.9 mph
Rollerblades____________________4:09____14.5 mph
Sk8 Flywheels (all push)________4:50____12.4 mph
Sk8 Kryptonics (push/pump)______5:06____11.8 mph
Sk8 Drop Shlong (all push)______5:06____11.8 mph
Chariot (all push)______________5:29____10.9 mph
Sk8 Tombstone___________________5:52____10.2 mph
Running_________________________7:01_____8.6 mph
Walking (normal pace)__________18:02_____3.3 mph

None of the equipment is particularly high quality or well tuned or anything.. and I've never been any kind of athlete.. but the times should be fairly representative of the relative speeds of each method of transportation.

The chariot is this thing (found in the curbside trash, needs new skate bearings still):


and here's my road bike (it's geared for easy climbing instead of speed, note that the large gear on the chainring is fairly small)


Starting to get weirder I've found that it's often not possible to complete a mile.. because the technique and muscles required need training. I got a wicked shooting pain in my thigh about 1/2 mile into doing this one..

YouTube - Skateboarding with one rollerblade on

(but it's what you would expect, faster than skateboarding, slower than rollerblading)

And similarly.. the UHMW ice skates, they could be more efficient/faster than walking/running, but the design would need some refinement before a mile test.

Might start doing 1/4 mile sprints for all of them as well.. That gives a pretty accurate speed comparison, but doesn't show efficiency (how exhausting something is) as well as the mile.

you know those kangaroo boots that make you jump real high? imagine what it'd be like to push with one only on your pushing foot. def a lot easier on a tall board.

I'll definitely add "kangaroo boot on pushing foot" to the time trial to do list.

Aside from testing various projects of mine, that list includes:

skateboard:
-all push
-all pump
-pushing with one roller blade
-with two or more skaters taking turns drafting.
-with different wheels, ride heights.
-wearing a full fairing
-alternating pushing leg/pumping side (need to learn).
-pushing with one kangaroo boot.
-behind a fairing mounted on a car.
-carrying extra weight on different parts of rider/board.
-on different types of pavement (rough, smooth, wet, etc).
-with and against various wind speeds.
mountainboard
various other hybrids (are any of them as fast/easy to push as a longboard?)
ice skates on pavement

If you think of other skate related things that you're curious about the relative speed/efficiency of, post em up.

And in case you couldn't tell.. the idea behind the UHMW skates is looking for methods to improve skateboard pushing speed/efficiency. In this case ultimately a shoe that slides forward but grips sideways, very similar in effect to pushing with one rollerblade, but much more shoe-like. The shoes would also work as rollerblades.. but who needs that?

today though, my art teacher had a lecture about this book he wrote on creative reuse...
and one artist shown in it reminded me a lot of the stuff that you do.

You really got my number there guy..
I went to Mass College of Art for sculpture, and I've definitely built a few janky bikes..
Here's some peeks at a couple things that are still hanging around (from the ceiling).




I don't think about the art world much though.. The formal commercial/institutional structure of it doesn't have any interest to me (dropped out of Massart after 3 years: took the good classes, met the good people, nothing left for me after that).

This is my favorite bike off that guys site though:

I have a lot of similar ideas tumbling around for bounce propelled skateboards.

As far as the reuse thing goes.. I'm not doing it because it's green, or for the aesthetic. I'm doing it because it makes sense. Free, useful parts and materials? Yes please.

[DarkMatter]

Nice to see that a bunch of people responded. Interesting to also see some of the side-to-side wheels sandwiches people have going on.

I'd like to see something like a thin-ish layer of Kraffft slide wheel material on the outer layer of the wheel, going all the way around, and if that wears through, boom, your wheels have a new life (assuming they aren't flatspotted of suffering from any sort of funky wear). The next ring of wheel material could be something like a hard slide wheel or grippy carving wheel.

I'm liking the ideas for replaceable and interchangeable wheel materials!

At any rate, thanks for your responses!

[B-Boy Megatron]

Circle Boarding Sounds Like Torture Technique, Turns Out Not To Be

[kraffft]

Thanks to Pigmoder for telling me about this one..

It's an invention from the 70's.. I don't know any commercial or colloquial name for it, and this is just made from hearing the idea.. I've never seen one.

It's a plastic wedge that makes it easy to get over curbs:

YouTube - Plastic Wedge

It will do any height curb that you can get the front wheels over, and really makes it easy and fun to get over them.. a dramatic contrast to your usual longboard ride, and really useful for traveling around the city.

It works very well heading straight at a curb, and less and less well the more parallel you get to the curb. As your angle of approach gets closer to parallel you start sliding sideways on the wedge until the back wheels catch the curb and track you straight again, but the lower the curb the closer to parallel your approach can be with no worries.

This is a good example of a product any small builder can make, that would be easy to sell for a fair price. It could be sold in various heights, like 1/4 inch increments; custom made; or sold with it's own risers.

The ideal exact height of the point of the wedge is somewhat elusive.. partly depends on the size of your wheels, and how large the debris is you want to be able to ride over. The wedge can get caught up on rocks similar your hanger getting stopped by a rock, but the point also wears down naturally to a good clearance.

And certainly there's lots of different possible designs stemming from the same principle.

[scratch]

Thanks to Pigmoder for telling me about this one..

It's an invention from the 70's.. I don't know any commercial or colloquial name for it, and this is just made from hearing the idea.. I've never seen one.

It's a plastic wedge that makes it easy to get over curbs:

They were in use well into the 80's and very common... think I gots some in my attic... I'll dig round for ya (& the Drill will be in my shop by weds...)

[jmasta]

not gonna lie, that wedge is pretty awesome

[rodgon]

for going up hill.

what about using a type of motor that can be shut down or put into neutral when you decide to bomb the hill again? wouldnt have to be the fastest motor, just something that can take you up the hill at a moderate speed to avoid the walk.

the concept of putting it into neutral is the tricky part, making it not affect the wheels when you want to hit the hill again is what stops me.

( not a great engineer... lol but if you come up with something that could work, i would love to get one or a tutorial of how to make one ^_^)

i cant ollie for my life... i think i might make myself a little wedge too ! looks awesome!

[speshlspeclsteak]

the production versions were called lappers

[kraffft]

This is my favorite movie of all time:

Gizmo! (1977)

If anyone can tell me where/how to watch the original film clips (like the director did to make the movie) I'd be very grateful..

The section focusing on the wheel starts at around 7:22 in this clip (preceded by some early parkour).

YouTube - GIZMO, part 5 of 8

or 45:14 in the full 80 minute movie on google video:

GIZMO

these slide gloves that sort of use really small wheels imbeded in the glove which obviously roll rather then slide.

This thread is apparently responsible for their early demise as a commercial product (in the U.S. at least?):

http://www.silverfishlongboarding.co...-ball-pad.html

Magnum Skateboard Wheels by Grand Prix Skateboards

simpsons did it

From the link you posted:
"This design is a taper lock system, which allows the rims to self center and lock into a wheel (tire assembly). This taper lock wheel is manufactured from 6061-T6 aluminum to a tolerance of .0002 and utilizes a 3 bearing setup to reduce side loading. The advantage of the assembly is to allow the replacement of different size tires using the same rims. The over all result is a very true spinning wheel at an affordable price." ($80/set)

I don't think the main part of my version of the idea has been done.. The main goal being to make consumable wheels as cheap as possible. For example Otangs can cost what? $55? and wear out in 4 hours? What if you could have the same wheel and just replace the outer layer.. retread the wheels for say $10/set?

I would assume that big companies would be hesitant to do this.. mainly out of greed.. but they would probably make even more money with this approach, assuming their urethane is desirable.

I'll look into doing this with the UHMW wheels anyway (similar to DarkMatter's suggestion).. Urethane is a lot pricier than UHMW though, so there's a much bigger potential material cost savings with urethane wheels.

ok maybe you could make the split duro but better as in the sandwiched type, inner half of it harder for speed then the outer half softer to grip round corners would this work??????

I'm going to collect different approaches to the problem of a wheel that gives faster straight line travel and better grip in turns.. and let the ideas percolate for a bit..

Leonardo was your mentor..no?

Donatello does machines..no?

But yeah.. I'd like to learn more about a lot of different inventors past and present.. it's easy to put off though. I bet there's some group somewhere that's dedicated to building all of Da Vinci's sketches.

Circle Boarding Sounds Like Torture Technique, Turns Out Not To Be

The circle board vid was frustrating to watch, having seen this:

Kept waiting for the guy to at least try a cartwheel.

for going up hill.
what about using a type of motor that can be shut down or put into neutral when you decide to bomb the hill again?

Putting motors on boards is another thing that I have an irrational prejudice against (though putting a board on a car is ok?)..

Also going uphill is very hard for electric motors.. you need a decent horsepower motor, and a big battery.

The shifting into neutral is doable in a lot of ways.

Various similar projects circulating the internet:

drill powered bike


drill powered skateboard


weedwacker wheel


If you watch videos of these types of things you won't usually see them going up hill.. and obviously they work better with 50lb kids riding them. The trade show demos are also obviously using high quality drills and the batteries are most likely brand new.

doing these types of searches will also tend to turn up all the most popular maker/builder/hacker sites:
instructables
makezine
zetomax
lifehacker
hackaday
slashdot
thisoldhouse
etc.

[jmasta]

how about UHMW coated wheelwells? wheelbite is essentially due to the friction between the wheel and the wooden deck. reduce friction... reduce chances of wheelbite?

[Barf]

how about UHMW coated wheelwells? wheelbite is essentially due to the friction between the wheel and the wooden deck. reduce friction... reduce chances of wheelbite?

Google up "Sliptape". I dunno if it's made from UHMW or not, but it's low-friction plastic in an adhesive sheet, you put it on the bottom of your deck for longer, smoother slides.. not to mention abrasion protection for the wood. Reckon you could cut little bits for just your wheelwells if you wanted to.

[sk8norcal]

krafftt, i like that 'plastic wedge', always wanted to make one..
u should market that thing..
there were many giant lappers in the 70's..




i got a 'kraffft' section on my wackyboard page now...

wackyboards: }kraffft