I've been trying to build a gybe simulator to help someone learn on dry land. I've seen pictures of the turf dog but didn't want to go that way as that seemed more for freestyle moves, but i may be wrong.
The intention was to make someting that goes slow on sand or grass, low to the ground, and steered by tilting the deck. See photo. Feels like it should work but haven't tried with wind yet, although it skates ok.
Questions; 1/does it look like it will do the job? 2/ did i make it too short - 890 mm wheelbase. On a real windsurfer the distance stern to mastfoot is about 1300mm 3/ where should the mast foot go - over the front axle?
Dear Friend,
Congratulations. You are a handyman. I like your simulator. In my opinion ,if we consider the aerrodynamics and the hydrodynamics rules, your project won't help people to learn gybing on dry land. But with this device people can make speed on dry land. Please inform us after your test. Good luck..
I do not see any pictures of yours.
People from the northern hemisphere are familiar with a concept of ice-boarding. There are some small outfits that make ice-boards in Europe. Here is one of them: www.hiberna.lv/Site/Hi_Boards.html
They all look like an oversized skate-board with trucks that turn when you are banking the board. I take the blades off and put an axle with wheels on it when the ice is gone. Works like a charm for jibes.
having lots or trouble uploading images...
sl55 - thanks for that. I looked the board up - its 1680mm so much longer than mine. You just put the mast foot through the slot at the front?
melih - you might very well be right! Maybe it will just be another land yacht..
I hope there is stops that would not let the wheels jam up against the board or your going to be in a bit of trouble ..
I had one of these years ago, and it was the best piece of windsurfing kit I ever had. I think it would help with footwork and sail rotation for gybing, but maybe not with weight distribution that is so critical to getting it right on the water (as Meatloaf said, 2 out of 3 ain't bad).
I tracked down this guy in France, and have been meaning to buy the wheel and truck kit and make the board myself. With the Aussie dollar pushing up, maybe now is the time. www.speedsailshop.com/en_GB
I reckon yours will probably work. Now that you have built it there is only one way to find out. Looks like you've put a bit of time and thought into it.
Clarence
Rebuilt the board to be 1300mm long and with the mast foot over the front axle.
!st go today. Wind 10knots and gusty, 4m sail, school playground hard and bumpy grass.
Biggest problem I had from the start was I couldn't steer the board to the right position to the wind with mast pressure and the sail.
The tension in the board steering and leveling mech. was too low so it was really tippy. In fact it felt just like a short board in not enough wind..then when I found the power it was like lifting a small board up on to the plane. Once going it was ok but the steering had the wobbles - stable direction but not enough damping. Did respond to foot steering in a sloppy way.
Got going reasonably fast - probably terrifying on asphalt.
So, fun and kind of like windsurfing but could be better. Back to the drawing board.
options
1/ try to fix the problems - stiffer steering/ leveling and/or damping
2/ go to a new design like the one above which looks to have skateboard trucks?. Can't be sure how the French design works but may be like this.
3/ The Swedish one higher up seems to use a combination steel spring/rubber device to allow carving - different to a skateboard truck.
3/ go to the turf dog idea with castors on the front, skateboard truck on the back. The advantage of this design is I think you could move the board with the sail, which would make things a lot easier.
If it's a gybe simulator to help people learn then you need to add a brake that is activated by people leaning back so it simulates stalling the board. That's the biggest and most persistent cause of failed gybes.
Just buy a landboard and drill a hole in it to mount the mast base, I picked this one up for $100. used to use it on the local netball court, would get scary fast in any wind over 10 knots though.
J 
I wonder it is such a good idea to zip around on hard surfaces, especially concrete surface on a wind powered skateboard ? One of the amigos shown here didn't even have protection of any kind.
Crashing into water while doing a gybe may hurt your pride a bit. However, on a hard surface, I believe more than just your pride would be hurt.
Well I just bought a land board today, like the one in the picture, although with conventional trucks. I was thinking of going the turfdog way, with the castors on the front - just from the problems I had getting the board to the right place relative to the wind, although my board was very heavy and not steerable unless I stood on it. The guy who designed the turfdog has done the work for me...
I do wonder about the short wheelbase though - wouldn't a longer wheelbase simulate a real board better?
Yes, hard surfaces do worry me. A fall in to water is nothing. The other day when things got out of hand I decided the best thing is just let go of everything and hop off - works on grass but the tennis court isn't likely to be as forgiving. Will wear a helmet from now on. Maybe its possible to incorporate a brake to keep the speed down?
Built the turf dog style board and it works pretty well. Sail pressure can be used to orient the board.
Problems starting as the front wheels tended to dig into the lumpy sandy soil where I was using it - which is solved by dabbing the ground a bit with the foot , - and at speed the front wheels judder - the castors are stable but lack damping. Don't know how to fix this - maybe don't bother.
For gybing it needs speed else it just stops which is good to learn. All in all a great project.
when u r ready for some asphalt/ "ass faults" (pardon the pun)
use what SL55 suggests or a cheaper option is the windskate
gtj has posted here on occasion and runs pages.infinit.net/gtj101/home.htm - vous parlez francais n'est-ce pas ?
it has taken some time, but other locals are now joining Guy at the shopping centres of South Shore in Montreal
