Tamiya KV-1 turret rotation problem...

[Jofaur86]

Having had a quick look at Tamiya's build manual the turret rotation motor is powered from the DMD mfu but it's not clear how as l can only see one orange lead. I wonder if the Futaba radio stick trim is so far off centre that it's only allowing one direction to work?

I don't know the new Tamiya systems? but am surprised that there is only one wire on the motor? do you have a picture? isn't there a problem either due to the famous disengageable pinion existing on all Tamiya gears? the transmitter is with mechanical or electronic trim?

[General Jumbo01]

Just Google the manual. Just declares one orange wire but as you'd expect there are two. Problem now identified as a fault in the mfu.

[easy8]

Hello DonCarlos,
Maybe a last suggestion before you claim a malfunction at Tamiya. You are using a Futaba T6L Radio. Behind the batteries there is a small compartment that holds a dipswitch (what I remembered from one of my old TX's) Are all dipswitches in the downside position? If not, then there might be a mixed setting that cause your problem. Please refer your Futaba manual.

best regards easy8

[Jofaur86]

Personally, I would say that if the motor works in one direction and not in the other? for me not a problem with MFU? Do you have the controls on the transmitter sticks, as indicated on the instructions? different attention depending on the brand of radio, also check if the direction of servos (on one channel) is not reversed? hence my question on the type of trimmer setting of the transmitter
For information
http://customrcmodels.com/Tanks/id92.htm

[General Jumbo01]

I tried swapping over the gun elevation and turret rotation connectors, as suggested. Good idea!
Guess what? The turret work fine both ways when I used the gun elevation stick, but the gun would only go down and not up. To me, that shows it has to be a DMD problem. I'm pursuing it with the Tamiya agents in the UK as a warranty problem. Worst case I can leave them swapped over as turret rotation is a more useful (or impressive?) function than gun elevation, but that seems a shame on a new kit that originally retailed for £970! Thanks for the suggestions.
BTW, I'm already thinking I need lower geared drive motors for a nearer scale speed. It accelerates way too fast...and top speed is crazy. What would a real KV-1 do? 30 kph maybe? That's 2 KPH roughly for the model. Oh dear. Slippery slope...

Keep up lads

[Jofaur86]

yes, sorry, can one reverse my answers? reading too fast .... my tanks are all Tamiya, I think? but that my personal opinion, according to my experiences, with these MFUs, and in view of what described, not convinced that MFU is worried? I wouldn't dwell on that more, have a nice day

[Ad Lav]

My guess is the motor is fubar - try a new motor first, I’ve got a few spares kicking around I think.

[Tiger6]

Before you warranty the DMD, I'd suggest swapping the elevation and rotation channels on the receiver and confirm that the transmitter stick isn't the problem - like it ended up being in my case.
Nevermind - I re-read your earlier post and you said you had confirmed this

I've acquired a significant number of DMD's over the last 10 years, and I've yet to have a duff one.

The MFU is a little more fragile - especially the recoil circuit, that blows really easily if the gun barrel sticks for any reason (so be extra carefull how you paint the gun barrel, and check it slides smoothly by hand before testing it with the motor connected!) and the flash operation can be a little flakey (or even fail altogether, Tamiya seem to have fallen afoul of fake capacitors in the supply chain for a while in the early 2010's)

[Jofaur86]

I agree with Tiger 6, why did I put this link, often we imagine that it is enough to follow what indicated on the Tamiya manual? each receiver not having the same functions on the same channel, depending on the brand, the Mode? Usually 1 or 2 for our tanks and depending on our choice of stick usage, after that, like Tiger6 says, before using the warranty, I would just check these points. Already plug in a servo on each channel, and see which stick does what ?
http://customrcmodels.com/Tanks/id92.htm