he’s my 2 speed gear box. works great.
please post comments
Not Bad. I made one as well but it didn’t work quite as well as I hoped (not to imply that it didn’t work :rolleyes: ). I’ll try to find pictures of it. I’m not sure where they are.
very impressive, have you used it with wheels? if so which ones work best :D?
also how did you make the gear changing servo set up thingy?..i can’t see it really 
Check this out. It has images of another shifting bot with much better detail.
http://www.team498.org/imagesSpeedy.htm
sweet 
thanks alot
(lolll at first i thought that guy’s name said andy milonokis)
here’s the bot i built around the gear box and a better pic of the shifter below took me several try’s to get the shifter. but i’m going to refine the gearbox down smaller so it can be added to other bots as well.
Nice.
Does it shift smoothly on-the-fly (while the bot is moving)? Or is there some grinding involved before the gears mesh?
It looks like you could have put the transmission’s two output gears (the high and low gears) closer together (for smoother shifting?). Are they at the currecnt spacing for a special reason?
A comment for the Vex folks to hear would be “Look at all the headache involved in getting linear motion (shifting), and in using those angled gussets, from a current Vex kit. You could say that the exercise is educational. I say ‘Yes; but it is also a giant pain the in the neck once you have done it once for education.’ I look forward to a few new parts showing up…”
i could probably push the gears closer… this was just a first test to see how i was going to do it. it shifts vary smoothly! only when it’s moving. if it’s not moving the gears just hit. but it shifts on the fly. becuse of the play in the server that shifts it i have it connected to “motor 5” u can just tap it eather direction and it will stay in gear without holding the servo one direction or the other. i think i’m going for a 3 speed more condenced 
they need a worm gear kit. would more for alot of new projects.
sorry but whats a worm gear kit :D?
This is a worm gear:
currently I’m working on a shfter of my own, as of two days ago, I have a design that will shift on the fly and stationary 100% of the time. it takes one servo to change gears, and has 2 drive motors (which will be 4 later on). it took about 3 weeks to perfect for everything to allign correctly. I’ll post some pictures when I get a chance
I have just completed a version of the gearbox that has a 60 tooth gear to a 36 or a 12 which is further geared via chain from 40 to 48. It shifts extremely wuickly and smoothly. I’m planning to upgrade it to use my pneumatics to shift even better and faster.
its a kit that has a worm gear it it. a worm gear is a gear that is long, skinny, and threaded like a screw so that you can decrease the speed of the output gear by ALOT with a small gearbox. not to mention that a worm gear also stops backdrive (the arm or wheels spinning the motors… bad). im surprised VEX doesnt have one it would be great to see
OK. After extensive (and by that I mean about half an hour) testing, programming and numerous battery re-charges I have some interesting data on my shifters. I have successfully reached 14.5 fps with standard VEX parts and only two motors to drive each side of the robot. I proudly decree the VEX “red zone” on the speed chart (here) broken . I have the robot programmed for automatic or manual shifting using a rotation sensor to measure the rpm of the drive shafts or the channel 6 buttons to shift up or down. I’ll try to have pictures and/or video up soon.
WOW! That is faster then almost EVERY FRC robot. You get some major props!
I’m pretty sure that my team, MOE 365, could do 20 fps when shifted . Alas it wasn’t fast enough and didn’t have enough traction at nationals.
There’s no picture… and it seems like there should be one.
Can someone PM me a picture of how it looks?
I have been wanting to do this and haven’t been able to quite figure it out.
i dont see the pic either, could you post another rather than PM everyone wo wants to see it?
There is no picture because the thread is old. Notice the date? its from July of 2006. Chances are the picture wasn’t hosted on the forum but by a free picture hosting website.