Now my KT's turret can turn left/right properly!(Updated)

[Chang]

Hi my KT fellows,
I have done the assembling of the KT and run several times. It's quite enjoyable to hear the engine roaring and track clinking sounds.

Recently there is a problem: the turret can turn clockwise continuously without problem, but get stuck on turning counter-clockwise at about 10 o'clock direction. (See video here at about 3'23", 5'00", and after 5'43"):


All lock screws on front deck are locked. The rear of the deck wasn't locked due to a modification underside (See 2 photos below):



Before I do lock all screws on the front deck, this problem happened a few times, but now almost every times.

Does anybody have the similar problem? What may have caused the problem?

Thanks in advance.
Regards,

Lerh Chang

[Adrian Harris]

If you remove the turret, are there any areas on the brass turret ring which show signs of friction - scoring or polished areas ?

Adrian

[David Ward]

Hello Chang

You may find the rotation motor bracket is moving slightly even if it seems to be secured well. ( It is under a lot of stress)
In that direction of rotation if it moves it all tends to lock up. Once it was in the correct position I held the bracket to the deck with two extra bolts that were a nice tight fit in the new holes to prevent any movement.

David

[Chang]

Thanks Adrian and David for advices.

Here is a new short film on this issue: (This time it got stuck on 12 o'clock high!)


L C

[Ad Wouterse]

Hi Lehr,

After listening to the soundtrack I must agree with David.
The rattling sound indicates that the gears are not lined-up.
It may be that the motor is not fully fixed, or that the gear ring underneath the turret is not centered (which is most unlikely).
Good luck.

[Chang]

Hi David and Ad,
Thanks for advices.
I now lock two L-shape angle brackets to the front and rear of the motor brackets, tightly stop the bracket from moving while working.



It does much help on eliminating the problems.

I also add 2 extension springs, mounted on small brackets that locked on the extended tube & a big bolt screwed on the end of the gun barrel. They can help to the gun elevation motor working:



The short film below shows both works:


Regards,
Lerh Chang

[Edward Earp, Jr.]

Hi Mr. Chang !! I'm right next door to you here in Texas. This KT is my fist venture away from gas model aircraft.......certainly a change !! I am learning everything the hard way.....very hard. Your photos of the turret are, as they say, worth a thousand words. More in my case. I am sure glad to see the pipe nipple.....I recognized something !!! When the time comes I will certainly use your photos. Thanks for putting them in the Forum.
I am having no luck at all finding the little channels for the underside of the deck !! Where did you get them? Also I am in great need of 30 - or more 7ba std. hex head steel bolts x 30mm long with 1/2" 7ba threads of 7ba with std. steel hex nuts.......used to hold wheels together on the KT.
Any help will be more than appreciated. Neither Steve or Mike have the bolts. Your correspondence and photos in the Forum are more help than you probably realize. Thank you much !!!! Ed Earp, Jr.

[Chang]

Hi Ed Earp Jr.,

Thanks for your compliment. The 10mm channels were bought from local (but big) hardware shop. The idea was from Simon Manning.

The added brakcets are also from local shop. The gun's big bolt/spring idea was from John Grima.

The little screws/nuts are shared with friends, but many on line shops could be found on this Forum. Not to mentions many marvelous builders here too.

Having no lathe/mills, all hardwares added are bought in, modified if necessary. They are rather operational than beautiful.

Happy modelling!
Regards,
Lerh Chang

[Edward Earp, Jr.]

Hi Chang ! Thanks for the answer. I'm in the same boat, having no lathe or milling machine. I'll just keep trying for the bolts and channel.
Ed