Ahlfors' panther G

[cahlfors]

Thanks Bob!
Well, there is considerable axial play on the original parts as well and Vincent's tracks had 1,5mm greater distance between the horns. To remove as much as we dare of the play, we have landed at 4mm; both on the sprockets and the rest.


A bit of a nuisance showed itself with the idler bearings:
https://youtu.be/14qqJEuxWN8



A panther friend told me that it needs to be fixed with a bushing insert, so I looked around at the material I had to see if I could find something that could be made to fit and whaddayaknow!

Cut the tube to size and a bit of turning on the lathe:

The fit was not as tight as I aimed for, thanks to my lack of skills, therefore a bit of high strength retainer was added:

After the surgery:
https://youtu.be/pOn6doh44_Y




Happy again!
Next step is wheel alignment. It appears that the O-ring between the wheel halves takes up any axial play, while not exerting too much axial pressure on the bearings. Making a suitable "axle extension" is quite critical. A little too thin and the bearings will pinch. A little too thick and the wheel halves will move and wobble.

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[cahlfors]

For the required increase in track horn width, I came up with parts like these. The disk is a "hub extension" and the little cylinder an axle extension. It took a few iterations to get the length of the axle extension just right, not to cause either binding or looseness:

Installed, it looks like this:

There is a larger disk for the twin wheel, but it works the same.


For the purpose of checking alignment and dimensions, a temporary idler was printed:

I had to do a little adjustment in the lathe for the bearings to fit and for the tracking to be right:

And with the track installed:

Looks like it could be the start of something:

The result:

The idler was printed in ABS with 80% infill, but it is all hollowed out because the design is actually for a steel print. This will come later. I am surprised it can cope with the rather heavy steel track!

The model is now ready for the hobby exhibition at Aeroseum in Gothenburg next weekend. OK, it's just a mockup, but it can clearly be seen how these models are constructed, which I feel is just as interesting as seeing the completed models.

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[RC_BobM]

Fantastic Chris. By looks of the Idler your going for "Late" version! Super cool. Just watch video of Jimmy's track replacement (to Liams steel) as well. I need to get with it on building mine.
Best regards,
Bob