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Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 1:48 pm
by Biarnred
Im not sure of the scale but maybe consider one of those pins with pearlised (or other colour) ball on the end and shape/cut to size?
Alex
Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 2:26 pm
by silversurfer1947
The shaft of the device (does anyone know what they are called?) is 1.0 mm (hence the brass rod) and the ball at the end is 2.5mm. I think a lot of modern trucks, particularly American ones are fitted with something similar.
I have stripped down the turret rotation gearbox, reset the gears on their respective shafts and reassembled it. For about a second or two, it was fine, then back to what was happening it before. Watching what happened, I noticed that the motor moved the smallest fraction of an inch when power was applied. The brackets holding the motor in place are obviously inadequate. I need to find a way of keeping the worm tight against the toothed drive cog. If I hold the motor where it should be, it works perfectly.
Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 4:11 pm
by Max-U52
To replace the broken rod and ball I would look at tongue studs. They come in all different sizes of ball and could be easily adapted for your purpose. The stainless steel ones aren't very expensive, a couple dollars a piece.
Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 4:17 pm
by PainlessWolf
Good morning, SS1947,
As far as your motor mount issue goes, perhaps a rubber O ring to snug the motor against the mounts and drive cog. As for the shaft and ball width indicators, hie thee hence to a local Crafts store where you will find packs of round beads _already drilled _ in every size imaginable for pennys at the cost. Thread\glue them onto your excellent looking brass shafts and Bob's your Dads brother.
regards and following along,
Painless
Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 4:23 pm
by silversurfer1947
I would never thought of using studs. I found some for £0.99 a piece so I've ordered 4 to see how they look.
Thanks for the idea.

Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 4:25 pm
by silversurfer1947
Just read painless wolf's post. Another great idea. I will put that to the test as well.

Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 4:53 pm
by silversurfer1947
Whilst I ponder the turret rotation problem, I thought it best to check the steering servo operation after my adjustments, as originally it was exceedingly stiff. Wonders will never cease. It almost worked perfectly! The only problem was the servo arm fouled one of the power connections to the motor. Did I mention there's not a lot of room inside?

That was soon fixed when I bent the appropriate terminal out a little. My last check will be the drive system, which I shall tackle tomorrow. It was all done according to the instructions, but it is impossible to see how well everything meshes together and I have this horrible feeling the motor pinion is not connecting to the drive gears. I hope I'm wrong as to change it will require major work.
If I'm starting to ramble, please tell me to stop. It's been very interesting build so far, which has really tested me, as I thought it would. The help from everyone here has been fantastic, so thanks guys.

Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 7:24 pm
by Max-U52
silversurfer1947 wrote:I would never thought of using studs. I found some for £0.99 a piece so I've ordered 4 to see how they look.
Thanks for the idea.

Now I kinda feel bad because I think Painless has a better idea.
Wish I had thought of dat!!

Re: Metal Origins SdKfz 234/2 Puma
Posted: Fri Jun 02, 2017 7:33 pm
by silversurfer1947
Not a problem. Though if they don't work, I have no intention of getting anything pierced so I could make use of them not

Re: Metal Origins SdKfz 234/2 Puma
Posted: Sat Jun 03, 2017 10:26 am
by silversurfer1947
Just tested the main drive. The good news is that the motor responded to the transmitter signals. The bad news is that, as I feared, the drive pinion does not mesh with the gearbox. Annoying as I was very careful to assemble it exactly in accordance with the instructions.

It now means some major dismantling and resorting to trial and error until I can get it to work.