Metal Origins SdKfz 234/2 Puma

[silversurfer1947]

It has had another run on the test bed and I'm pleased to say that nothing has fallen off or stopped working. The left hand side wheels all run smoothly. The ones on the right not so. They bounce up and down a bit, which I think comes from the universal joints binding somewhere. There are two joints per wheel. I will strip them out, test and lubricate them one at a time. I would like to think it is all starting to come together.

[silversurfer1947]

Very disappointing. I've taken off one of the wheels with its universal joint at the hub. It seems to me that there is a fault in the machining of the part. I can't describe it in technical terms but it look like the swing axle is prevented from travelling the full distance because the slot in which it moves has not been fully cut. What is really annoying is that I paid extra for the supposedly better swing axles. This is not the first problem with them. Followers of this thread may recall that one stub axle had no flat machined on it and the hole for the wheel bolt was not threaded. Very poor quality control. I should have stuck with the kit ones, in hindsight.

I now have to remove the hub caps without damaging them, remove the wheel from the tub axle and completely dismantle the u-j assembly, then try to file the slot to give full motion. If push comes to shove, I can always fit the kit swing axles but that will be an absolute last resort.

That comment about it starting to come together you can disregard for the time being.

[PainlessWolf]

SS1947,
I've run into this to some degree with the metal MATO tank destroyer I am currently working on. I'm not sure what it is but perhaps the extra care needed to ensure that parts made of metal fit and work as intended, is escaping these fellows at some level. Props to you for slugging it out with the kit and continually working hard to bring it to fruition.
regards,
Painless

[c.rainford73]

Your persistence and efforts will pay off soon following along. Maybe snap a few pictures of the affected parts so we can see your handiwork on the needed repairs.

[silversurfer1947]

I've done a short video of the comparative performance of the wheels on the left and right hand sides.

phpBB [video]

As you can see in the first shot the wheels are reasonably well behaved. The movement is caused by the other side, which features in the second portion of the video.

I am a bit stumped at present with how to remove the hub caps. I recall they were an exceedingly tight push fit. I did not anticipate having to remove them. All I can think of at the moment is to drill out the centre to expose the bolt and then fill it in in after I have finished. Once again people, I am open to any suggestions.

[PainlessWolf]

Good morning S.S.1947
If the hubcaps are plastic, look for an area on the rim which may feature an indent or raised area. Carefully lever the cap up at this point using a jewelers flat blade screwdriver until you can see more of the sidewall of the cap. Continue levering around the circumference until the cap pops off. Slow work but if time is taken, you should be able to remove your caps undamaged. As for the behavior of the wheels, it looks like something is off round on whatever gear spline connects that set. Time for a very close inspection with calipers.
regards,
Painless

[silversurfer1947]

Thanks. Regarding the behaviour of the wheels, what I think is happening is that when they are are the limit of the suspension, as they are in video, the swing axles are actually following an elliptical path rather than circular as they are not able to move the full extent that they should because of the machining fault. (If that makes sense) I know when I first put to together, one axle universal joint was particuarly bad. It would hardly move at all in one plane so I filed it open until it moved freely.

[silversurfer1947]

One down (I hope), three to go. It was only after I had reassembled it, I thought I should have taken some detail photos so you can see what I have been wittering on abut. It may also help anyone else who decides to try this kit. I will do so on the next one.

[wibblywobbly]

Your description made perfect sense to me, though when watching the video my first thought was that the movement was just down to running it with the wheels off the ground.

Love the sound, this is going to be a great model when its finished...maybe even worth a run round Rhoose?

[silversurfer1947]

Rhoose sounds like a great idea. What I saw on the video shows a good test for any vehicle.