Hornby Q1 drive damage

[ed 66 plant]

I inadvertently left my Q1 lapping and it met another stationary loco at a junction (no collision damage as on slow running)  and I returned to see it stationary with drivers turning but making an irregular clicking noise.

Have dismantled and see that there is no damage to the worm or gear train but on reassembly I cannot get the motor worm to sit securely on the gear train--hence poor power transmission and noise.The prolonged running whilst stationary obviously upset the power train--has anybody else come across this and any ideas please?

ps I cannot get the rear motor bracket screw to hold the motor and worm securely--even when screwed right down.

Edited March 14, 2021 by ed 66 plant
omission

[ed 66 plant]

I trawled thro, this section and got a lead from a gentleman who had a similar problem with his T9---Remedy --he epoxy glued the motor to the cradle and so got meshing between motor worm and gear drive.I have just tried little strips of black tack on the edges of the cradle for the motor and can see that it is much improved but not permanently so when under load.

I also noticed that there were marks on either side of the cradle seemingly indicating the use of glue to help  secure the motor and worm .This seems to tie in with the cause of the failure--prolonged driving wheel rotation on the track when it has nowhere to go--the motor and worm are displaced when the securing glue fix fails?

My next approach will be the use of glue to secure the motor and worm output as a means of reliably transmitting power from the motor and worm thro, the gear train.

Hope this is not a boring monologue----I will update later --but remember the lead from elsewhere in this section of RMWEB

[Ben Alder]

I had a couple of T9's with mazak rot in the motor keeper and used evostick to hold the motor in place - left it a couple of days to set thoroughly and has worked OK now for two years or so.

 

[John Tomlinson]

It doesn't sound like your Q1 has mazak rot for which several T9's have become infamous. Rather the screw thread for the rear motor bracket into the body is worn and doesn't hold.

 

This isn't an uncommon problem with China made locos, as the metal in the castings, and that used for the screws, is often not of the greatest quality, and wears quite easily. So take a screw in and out a few times, particularly if you fasten it down very hard, and it ceases to grip. You could try wrapping something like plumbers PTFE tape around the screw iself before securing, to see if that gives a bit of bite. For future reference, when you replace screws into any model these days, it's worth turning the head anticlockwise before you start - as if to unscrew - listen carefully and you'll hear a click which means the screw has found the old thread and can now be tightened without creating extra wear. Don't overtighten, especially into plastic.

 

Otherwise glueing as mentioned is the only option I can see, I think some people have also used Silicon as used in the building industry, but that might be a bit fierce if you ever want to dismantle.

 

John