Loco wheels (and other issues) 7/8th scale

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Dave Cooper
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Loco wheels (and other issues) 7/8th scale

Post by Dave Cooper » Mon Mar 18, 2024 7:15 pm

Good evening folks.
I have hit a snag which I am hopeful can be assisted/sorted by some (or one) the great minds here.
I am planning to attend the gathering of 7/8th modellers at the W&L later this year. To which end, I am working towards have at least working loco to be able to pull my meagre, but growing, stock of wagons.
However, the PDF LAT kit (I actually have 2 of these so double the trouble) appears to have a few curious 'issues'. The main one being that the steel wheels (which have plastic centres) come fitted to axles of 3.35 dia as opposed to the 3.175 (1/8th inch) bore of the drive gear supplied, plus they are not long enough to fit between the frames.
So, my solution, before I realised the diameters did not match, was to simply cut new correct length axles. Easy, thinks I, new 1/8th axles, no problem!
So now I am stuck!
The bearings provided for the frames are ok with both axle sizes (a little wiggle room is ok for this in my book), however, the 1/8 axles float in the plastic centres of the provided wheels.
I know, I though, I can buy some 30mm dia steel wheels with 1/8th axle holes.
The question is, can I, or is there another way of solving thus problem?
Please note, with the best will in the world, I doubt PDF would be able to help with this so I have not approached Leanne.
I just hope someone can offer some help
Many thanks

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GTB
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Re: Loco wheels (and other issues) 7/8th scale

Post by GTB » Mon Mar 18, 2024 9:39 pm

Dave Cooper wrote: Mon Mar 18, 2024 7:15 pm However, the PDF LAT kit (I actually have 2 of these so double the trouble) appears to have a few curious 'issues'. The main one being that the steel wheels (which have plastic centres) come fitted to axles of 3.35 dia as opposed to the 3.175 (1/8th inch) bore of the drive gear supplied, plus they are not long enough to fit between the frames.
3.35 mm is gauge 41 music wire (piano wire) size. A strange choice for axles.......???????

Do you have, or have access to, a lathe? I turn my own wheelsets and my reaction to this sort of thing would be turn replacement bushes for 1/8" dia. axles.

Commercially, IP Engineering was using 1/8" dia. axles with his 30mm wheels the last time I bought any, but that was 10+ years ago, so you'd need to check the axle dia. and length with Ivan. Peter Binnie supplies 3mm axles with his 29mm wheelsets and lists a range of axle lengths on his website.

No idea what other commercial offerings are out there.......

Regards,
Graeme

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Re: Loco wheels (and other issues) 7/8th scale

Post by ge_rik » Mon Mar 18, 2024 10:18 pm

I've used Essel Engineering before now and he (Steve, I think), was happy to produce some steel disc wheels to my spec. He might be able and willing to help.

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Dave Cooper
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Re: Loco wheels (and other issues) 7/8th scale

Post by Dave Cooper » Mon Mar 18, 2024 11:28 pm

Since my original post I have discovered that the wheels 'may' be Sierra Valley items as they certainly look like them plus they have, what appear to be, the same plastic centres. Wether that has any bearing on the choice of axle size in this case is unclear as that specified now is entirely different from the 'Train Department'. As you say GBT, the 41 gauge piano wire size does seem very odd.
I can only assume that a decision was made at the time as to why such a choice made sense however it doesn't explain why the gear bore is clearly 1/8th. How one is supposed to marry the two is a mystery, to me at least.
I don't have a lathe so I expect to have to get someone to turn up some bushes to suit the adaptation needed, or I get someone like Essel to make new wheels. My feeling is bushes (metal I assume and then the whole ensemble 'glued' together?) would be easier as it would seem a waste to chuck perfectly good wheels for the sake of bushes.
More musing and investigation required I think.
Many thanks thus far gentlemen.

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Re: Loco wheels (and other issues) 7/8th scale

Post by -steves- » Tue Mar 19, 2024 8:57 am

Dave Cooper wrote: Mon Mar 18, 2024 11:28 pm Since my original post I have discovered that the wheels 'may' be Sierra Valley items as they certainly look like them plus they have, what appear to be, the same plastic centres. Wether that has any bearing on the choice of axle size in this case is unclear as that specified now is entirely different from the 'Train Department'. As you say GBT, the 41 gauge piano wire size does seem very odd.
I can only assume that a decision was made at the time as to why such a choice made sense however it doesn't explain why the gear bore is clearly 1/8th. How one is supposed to marry the two is a mystery, to me at least.
I don't have a lathe so I expect to have to get someone to turn up some bushes to suit the adaptation needed, or I get someone like Essel to make new wheels. My feeling is bushes (metal I assume and then the whole ensemble 'glued' together?) would be easier as it would seem a waste to chuck perfectly good wheels for the sake of bushes.
More musing and investigation required I think.
Many thanks thus far gentlemen.
Is it a brass drive gear? If so could you drill it out a bit to fit? Would that solve the issue? I know once I had a PDF kit and they supplied the wheels but also a new axle of which you had to remove the wheels from one and fit it to the other. Some pictures of the issues would definitely help come up with a fitting solution.
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Re: Loco wheels (and other issues) 7/8th scale

Post by Jbs » Tue Mar 19, 2024 10:04 am

My PDF 1/12th scale ruston kit came without axles and wheels so I used 3/16th axles and Essel wheels, easily regaugable between 32mm and 45mm. Wheel diameter I used is 32mm available in the Essel catalogue. They will also make wheels with wider treads for 7/8th and 1/12th scales.I bored out the axleboxes in the PDF chassis and inserted brass bearings for the axles and have had no problems so far. No connection with Essel other than as a satisfied customer.
I adopted the above method as I wanted more robust running gear after having had problems with long 1/8th axles in the past and the 3/16th axle diameter gives a selection of motor/gears readily available from 0 gauge suppliers.
John
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John Smith

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Re: Loco wheels (and other issues) 7/8th scale

Post by Dave Cooper » Tue Mar 19, 2024 3:48 pm

Thanks a million gents, you have given me plenty to consider.
It did occur to me that James Hilton build one of these so I may ask him what he did.

More pondering any way
Cheers
Dave

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