A fairly compact sequential gearbox with neutral gear and reverse. Here is the result after several months experimentation!!!!!
About this creation
The system can be seperated into three modules. The first of which is the 5 speed gear box plus reverse as shown in the following four images. It took a lot of experimentation to build a reliable gear change mechanism that did not exceed the achieved height. I also wanted to integrate the gear shift drive axles into the gearbox structure and minimise the distance between them to two studs. Neutral is achieved by using the slightly different selector paddle between reverse and first gear. It took me a while to accept that the outer row of selector paddles would have to be double the width of the inner row!! This configuration works really smoothly (I think) and is sturdy, even as a standalone entity.
The gear selection mechanism was difficult to get right, but I am really pleased with the result as it is fairly compact even though incorporating two individual selector mechanisms. It was necessary to have two selectors in order to achieve a travel distance of one stud per gear and also to allow for the neutral gear.
Gearbox and Selector Combined
Reverse Gear Selected
5th Gear Selected
Gear Stick and Ratchet Mechanism
This took the longest and the most experimentation. Making something that was strong enough to drive the gear selector and that didn't slip took a while to work out. In the end the solution looks fairly primitive (I think) but it seems to work well. There are a number of positions that this part could attach to the gear selector, I went with the simple option as shown in the pictures below of the complete mechanism.
After building the thing, I can tell you it works pretty well... haven't had it actually powered yet (as all the gear shifters I got went poof for the various blockable differentials on my axis), however the part I was testing for is size and performance of the racks and gear switchers... in other words, everything but the actual gears ^^
• Motorizing it didn't work too well, as the M-motor I assigned to it terribly failed. A XL motor does the job nicely, however is obviously a lot rougher on the setup if you're trying to shift up or down when you're at the respective limit. I didn't have any damage because of that after exhaustive testing though, so yeah...
• To make the stick return to center after shifting, I had to use one of the hockey spring-loaded center bricks (and might have to use one on the other side as well), as the rubber isn't enough to handle the strength it takes.
• Aside from all of that, it's a rather long setup, so my current concept involves trying to fit the shifting rack on the opposing side as the gear changer, to get more of a rectangular shape. I'll still have a lot of problems fitting it onto my model, but seeing how well it works is something that makes me really want to integrate it :x
Congrats on the good work again!
After messing 5 hours with LD, trying to get it working right, I figure I just can't get it to work on x64... meaning only the viewer works, which is a start, but not quite sufficient...
I wonder if you could like post a part list, or create a PDF with step-by-steps (think you can create these with LD)? I'd be immensely thankful :)
I also checked the dimensions with my current chassis, and I'd have to modify it quite a bit (for once, size isn't the issue because of my large-ass scale and your compactness ;) ), so yeah... basically I'm gonna try to build the transmission and see if I can get it incorporated then.
I'm really tempted to throw away my curent (2-speed) remote-controlable transmission and replace it with this... obviously, a 2-speed takes far less space than a sequential installation with quadruple gears, but seriously - this is an amazing construction you have there. I was already impressed with what Sheepo's got, but you improved it quite a bit, I think... might be because of the fact that the model I'm working on definately wouldn't be suitable for a 7-speed :/ (nevermind a big one like his).
When you throw your instructions out, I'll have a look at it... and I guess if it'd theoretically fit, I'd spend some more hours at the drawboard :|
Keep up the awesome work!