ThePog

Has the outer face of the housing been machined? Mine may need some fettling.

So I have been attempting to get the box back together, but it has taken 3 attempts so far; #1 - all the clusters back together, everything inserted and getting to put 5th gear on when I realised I was so intently following the written writup on Xweb that I had forgotten to put the actual gearshifting mech in because it wasnt part of the writup. Sigh, gently pull it apart and scrape off all the blue gasket poo. #2 - everything back together again but realising the there was some burring in one of the the detent ball holes and the now impossible to get out ball bearing was moving neither forwards nor backwards. Sigh, gently pull it apart, extract the ball and then scrape off all the blue gasket poo. #3 - slowly and methodically reassemble it all again, barely even referring to the writup cos there is now an element of familiarity with the process. I am still waiting for some axle seals, but apart from that its all done. Like the old box it has a tapered drain plug in a straight tapped hole, I think I will make a straight plug up so I dont split the case. Anyway there are very few pics of all this as it required much concentration.

I am now thinking it is just ring drag, it was easier to turn at tdc. I have put the bottom end back together now and had a good look at everything while I was doing it and found nothing untoward.

Actually the button could be for the plebs, what about a second input where I whistle the star trek comunicator noise to make it go?

Cheers @h4nd All of these methods are excellent, however a single go button would probably be the best. I was excited to bring you some scope creep but it seems you have addressed that, ruining my fun. I was going to ask if the bed could be stopped at any position by podging the button, this looks like it is solved. The button probably needs to be an estop as well, just in case there is need to stop it quickly... Otherwise that all looks spiffy. Edit; pull up resistors indication on your diagram?

@h4nd I have a couple of questions. What is the 'go' signal? Does the arduino need to be powered all the time or for a set amount of time to boot? The actuators have limit switches that cut the motor up or down, what happens in this condition? Does everything reset for the trip downwards with reversed polarity on the motors? At the moment this is just done with a dt switch taking all load.

There is also the added difficulty that I am a MechEng so inherently unable to understand coding. The sketch is mint tho. Plus I ordered spares of all the wee boards for when the magic smoke comes out.

Engine shop mans keen eye pointed this out On the lighter coloured cylinder too, so could well just be the head gasket. They are going to check it and give it a skim. There is a certain amount of scum that forms in the header tank, not much so I thought it was just clag from its long park up getting blown out, but maybe not..

Yea but how does that happen? The problem is that I don't know what fuckery went on in the intervening years...

I haven't had a real good look at the pistons but everything looks basically brand new, irl it has probably only done 15k or so since I put the engine together and it is clean as inside. When I bought the engine back in the day he had assembled the bottom end already, I took the mans word that he had rebuilt it properly so didnt bother to check anything, just finished assembling it. He was an aircraft engineer at AirNZ and told me he had lightened, balanced and weight matched everything, and I can see now that he definitely had done this. I just wish I could definitively find something causing the vibration....

Bottom end is mint, bearings are perfect still and without the pistons in the crank spins freely. Ill take the head to Mean Machine tomorrow to get it looked over, see what they have to say.

Legend I was going to model them up for printing, which leaves room for shenanigans...

Opened things up a bit more, tbh it looks pretty good. Altho number 2 is slightly browner than the rest in the head. The cam spins nice and free so its not that, but the with the head off rotating the crank is still ever so slight weirdly variable in turning force. The bores look basically perfect so maybe that means the crank might be bent? Rings broken?Time will tell I guess.

Pulled the drivetrain out tonight and pulled the sump off to take a look. I hope my engine stand won't buckle under the strain lols I can't see any wrong in there, the sump is 100% perfectly clear of debris. And everything looks great, no missing chunks of piston or the like. There is however a noticable variation in turning resistance with the plugs out, I am suspecting a slightly bent valve or broken valve spring. I am waiting for a new head gasket and bolts before I get too carried away. Also: so many gearboxes, this isnt even all of them, I have 2 more.

Ill need to check with a bit more weight on there, but 4x actuators were pulling about 8 amps total. I have already made/tried something that was linked chain driven sprockets with acme thread and lift nuts with 3d printed drive mounts, but the compounding frictions made it unworkable. So now I have a shitload of acme thread and chain lying around waiting for the project that might need them...