Two new UC builds

[Dennis Jones]

[Dennis Jones]

Finally sorted out the brake servo system, took a bit of fettling but got there eventually. The warp servo system seems to work ok on the bench anyway. I am going to use NIm/h batteries not lipo. I can make up a 6 pack (7.2 volts) of D cells rated at 10 amps for about £40. Another advantage is that it will fit in under the engine cover and can be left in place for charging, just need to change the jumper on the speed controller from lipo to n/mh.
Had to take out 3 links and still not enough as drive sprocket wouldn't grip track, ran out of time yesterday as Wales playing England and being a true Welshman couldn't miss that especially as we won, so will carry on today.

[Tim Page]

It was a superb win over the Old Enemy Dennis.
Controversial maybe, but a win all the same.
It almost makes up for that other French Ref who destroyed our World Cup dreams back in 2011.

Nice to see you progressing with the UC and also nice to see some shots of the electrics and control components.
I would be very interested to see what the Motion Pack looks like and where it will be placed in the model as there is not a lot of room.

Cheers
Tim

[Mick Regan]

Tim

The motion pack for the UC is an ESC, similar to what would be used in a large r/c car. The motor is an RS550 with Armortek’s gearbox attached. It all fits very easily under the engine cover.

[Dennis Jones]

Just found out why drive sprockets not gripping track. Numpty me I had put the bogie wheels on the wrong way round so they were out of line with the drive sprocket, should have looked closer at the manual.

Dennis.

[Dennis Jones]

I am still having problems with the drive system. Got the brakes working but sometimes one will jam in the on position, there's got to be a better way of controlling the brakes. The reason that brake jams on is because it is only relying on the spring to pull it off and I am reluctant to put a stronger spring on as that will put extra strain on the servo. I have had the back axle back off and made sure there is no binding in the levers.

Also I have found that the drive sprocket doesn't mesh properly with the tracks, as anybody else had this problem. I have removed quite a lot of links as I found with the recommended 162 links it wouldn't even drive.

Dennis.

[Armortek]

Make sure that the entire braking mechanism runs very smoothly. ER1608 needs to have the edges taken off as per the manual as any sideways movement in the mechanism can cause ER1608 to stick in the housing and make the servo have to work harder.

[Dennis Jones]

All rivetted, no superglue.

Dennis.

[Mike Keenan]

This is my first look at the brake system as I have yet to receive mine, and the first thing I see is the return spring is pulling of centre which would nt help with smooth engagement or release. Just my thoughts

[Dennis Jones]

More or less finished but unfortunately during test both servos have burnt out, they were only set at 30% travel. I might be wrong but I am not sure powering the servos with 7.2 volts is a good idea so I might be thinking a different system.
Anyway time now to start on the second build, this one should go easier having built one already.

Dennis.

[Brian Ostlind]

I think the servos are just very basic not a voltage problem but a torque issue. Of course there are many options for upgrades. I have servos with over 900 ounce stall rating up to 8.4 v.

[Mick Regan]

Dennis

I’ve been looking for a data sheet from the manufacturer, but can’t find one! Various website quote a maximum voltage of between 6.8 to 8.4 volts? Not very helpful.

Mick

[Dennis Jones]

Visited Bovington today, very impressed with the new WW11 exhibition area. Took some photos of the UC there.

Dennis.

[Graham P Hough]

Brilliant set of photographs, thank you.

[John Clarke]

Great original set of pictures very helpful.