Im putting this in here to keep my build thread a bit tidier. Ill be building/converting an 02A to sequential. Ill be making all I need to complete the job. Ill run a corkscrew style drum to control the forks. Ill have to remake case in order to fit the drum in. Ill also have to cast/make new selector forks. Ill be machining the drum myself also, and it will be done manually, not with a cnc. The drum will be controlled with a servo motor on one end. The servo/stepper will be run from a controller, which in turn will be controlled by paddles on the steering wheel. Shift speed, input angles, and the dwell time it takes for the syncros to engage is programmable within the control code that I will have to write for the controller. Im going to try take in reverser gear on the one drum too, and not on another lever. Im confident I can machine one drum to control 1-5th gear forks. I could machine 2 to time the forks better, but since this is not F1 I think one will be ok. Two are sometimes used, one lets say moves 1st gear fork, as that is disengaging, you bring the other drum into play to start engaging the 2nd gear fork, this cuts time, and both drums can be timed very close, and it also rules out any drum groove/selector slop. But, as I said, Ive looked at it, and I think one is ok. Its something Ive always thought about, and Im now going to do it. It will be a long one, expect about 8months, but Im confident I can pull it off. Im going to cover everything I face on the path, so itll be all in here from the start, from looking where it will fit, to thoughts, materials, machining, electrical control, servo/stepper choice, drawings, etc. We are now in a new year, I promised myself Id have two things done by this time next yr, this is one, the 16v cylinder head is the other. I will also be finishing my 8v build thread throughout the yr too, to have something to do/run, while Im at this, and the 16v head. This gearbox build is just posted on this site, its simply too much work anymore doing/copying multiple posts to other sites. Every issue I face, I will post it up now that Im just posting in one place. Even stuff as simple as the difference between a servo, and stepper motor, to writing the control code. The control code is the one thing I may need help on, my brother has offered to write it if I get bogged down, but, I have a few simulation boards made, and, so far, it seems okish. So thats pretty much it, It will be slow, and Im sure intense at times. I get bored easy, and always need something to keep my head going, I think this will do that nicely. I see no problem in pulling it all off, its just going to take time, and lots of thinking. Posting this is the first step, Ill post up a few pictures of case and shafts later, just to show what Im faced with, as it comes. Then I will start drawings, and proposed plans, pretty much how you cope with any design brief and how things develop. Im excited about it, its a good challenge, some may see it as pointless, but its something Ive always dreamt of, electric paddle shift in a mk2! Clutch will be kept, as will clutch pedal, I know some of you are cringing, but, I wont be going dog box, as its my daily, but, Ill be finding out just how fast I can programme the changes on standard syncros. Plus, all the linkages, changer, tower, etc, will all be done away with. I will need some sort of digital display made too, but one of the chip outputs will host that for me easy. Ill also need a start in neutral lockout. Im sure theres loads more too, but the mechanical side of things are the biggest challenge at the minute. Happy new year Brian
Sounds like a very interesting project. Do electronically activated sequantial boxes currently exist? I've seen normal seq boxes with electronic paddle shift and hydraulic activators but not ones that are entirely electronic. I'll be watching this interest, good luck.
I have no idea! Servos can be got any size(Nm) so one will exist at some time this yr. The fact that none exist worries me if thats the case, but I dont see why its not possible. Its just a drum you have to turn at the end of the day. Perhaps building a lever hydro actuated control box onto the existing forks/levers is easier, that may be why. Edit, Google tells me some F1 boxes use/used direct electronic actuation
Sound like a ridiculous amount of work, but I'd be impressed if you manage it. Wanna buy a DSG box with all the wiring and shafts?
Wow, nothing like jumping in to another fine project. You'd better crack on, there are only 360 days left of this year.
Thats pretty much what I had in mind, I like how the channels sit out from the main shaft, cuts down mass, and puts the moment of inertia nearer centre. Another words, lighter so it can be turned faster. BG
I believe everyone is You just have to do it If you think you cant, you wont. I try not have negative thoughts.
And away we go! First proper look at box, casing, architecture, ribs, all that, its tight, but of course do-able. The baulk rings are of course on the shaft on the right. And to be awkward, 5th is on the other shaft, on the outer end under tin cover. I can say right away that the tin cover will be going to make way for a cast item. Incase anyone wants a refresh on how a seq box works, heres a drawing of one, big thanks to Tony Matthews for this, The drum is turned a few degrees every time you want to change gear, the forks have pegs that sit in corkscrew cuts in selector drum, as the drum is turned it moves the corresponding fork which, selects the gear. So thats how it works, and its what I have to pack in to the 02A(somehow!) Back to the box, Ideally Id like to have the fork pillar near the gear cluster to cut down on fork deflection, and have it compact in general. I must warn you now, and early, that sometimes I dont exactly know the correct name for stuff, and sometimes make up my own names for what that I think suit. But you should know what Im talking about hopefully The valve is left roughly where Id like to place the fork pillar(bar they are all stacked on) You may have guessed I will have to take a section out of the case. Ill make sure it is the correct shape for strength, and make up a cast item to cover the hole again and cover all the bits I add. This will be bolted/bonded, so it will be find. Ill look at all the stress concentrations in that area later, and as I progress before cutting or drawing anything. The same area, outside, Spot the important web I wont be touching at any cost, No point building something and then having to drive it like a fairy, if its going to break, Ill break it. The approx exit point of fork pillar, this has to come out here to also carry the 5th gear baulk ring/fork(somehow) Some pictures Ill post, but not comment on, they are for your own viewing/thinking/etc, and mine too! Just general stuff that has to be dealt around, Im going to stack the shafts in there later, and stick on 5th gear without the top case to see how we look, only about a million hours to go BG
I suspect the reduction in moment of inertia is negligible on something with that radius at ~1rad/s but it's still nice to have things light. Those Tony Matthews cutaways are incredible. The autosport forums have a 180+ page thread all about them. Including the infamous Ilmor pushrod engine. Sorry that's a bit OT but thought you might appreciate that sort of thing. Keep up the good work.
I like You have rather large mellons though This is a good thing mind You'll need them too GET BACK IN THE WORKSHOP!
Im a long way off the workshop yet! And thankfully so, because its -3 out there again[:^(] Dropped in the shafts, Fiddled around with proposed 'stuff' locations, Reverse is a million miles away from proposed drum/pilliar, so this will need a separate actuator of the linear type. Theres plenty of room around it for one, attaching it to the gear should be fairly simple. Pillar could go here, Possible Drum location being the camshaft Clutch master cylinder is near too, Leaves the 5th gear fork a little longer than the other cluster, but looks ok for the minute. Ill start to burn a few brain cells later(the few Ive left) BG
Another thought, Putting the drum outside the case and have the dowel pins sticking out feels like a good idea. The drum could sit in camshaft like bearings with caps, that would mean its all take-apartable, and put-togetherable too. Very important!
Needless to say this project of yours has been rattling round my head since you launched the idea. My general thoughts are that the VW boxes, both 020 and 02A/J are awkward in that 5th is outboard of the main case. They also have a limited range of ratios in the 1st gear dept. I have a Ford MTX FWD box that houses all the gears in the main case, is very strong, and has a fair amount of ratios available from all the ranges of vehicles it was fitted too. 3.2 1st and 1.05 5th to name a couple. I know of someone who has used this box in a competition Golf and latterly a Rover with just a bell housing adaptor plate and modified drive shafts. Just wondering if there was any reason that is restricting you to this particular box, or if you had considered other viable boxes that may be better suited to the conversion?
