YHR

Ok, I guess I( we) are out of luck with getting any parts to allow Heng Long or the Trumpeter Solid wheels to be used with this chassis. So if you want a RTR rolling chassis you will need to buy the metal wheels as well. So be aware of this.

I have parts and pieces coming, and I am going to try and come up with something to allow me to use the Trumpeter solid wheels.

So just want to pass this along if you are thinking of getting just the chassis. It will take some drilling, machining, bashing to get the stock wheels on this if you were thinking of using plastic wheels.

I have a large supply of old COX Slot car axles that I am going to dig out, and see if they can be used.

Cheers

YHR

Further update.

I was able to cut down a set of Heng Long tiger axle pins for use on this chassis. I had to ream out the holes in the suspension arms to accommodate these pins, but the set screw mounting set up make this an easy mod.

Now that I have a couple of wheels on, and I am working the suspension, I am noticing a problem. The plastic skin flexes away for the metal tub, and this splays out the suspension. I believe the fix for this is to run more screws through the plastic into the metal, or perhaps bond the plastic to the metal with epoxy.

I will get the camera out an post pictures now that I have a solution for the axle pins, and show this hull flex I am talking about

Cheers

YHR

I took some pictures

First picture shows how the plastic flexes away from the metal when the suspension is loaded.



I removed all the suspension arms to drill them out. I backed off all the screws that hold the plastic down, and stuck popsicles sticks between the plastic and metal. I mixed up some 5 minute epoxy and spread this between the plastic shell and metal, primarily focused at the point of greatest separation. This was set aside to dry for a couple of hours. Next picture shows the result when the suspension is loaded



So you can see the epoxy cured this problem.

The next picture shows how I modified the Heng Long Tiger axle pins to be used with this Taigen chassis. It involves cutting slightly more then the threads from the pins.



You then have to ream and enlarge the bore through the suspension arm so theses axles pins can be fitted.



Now that the axles pins are fitted into the suspension arms, you can add the Plastic wheels. In this case I wanted to use the Trumpeter solid wheels. I had no bearings on hand so I just used brass tubing cut to size to work as bushings. The result is a wheel that spins true and free. I have ordered some bearings and when these get here I will replace the bushings.....................maybe, as these spin pretty nice as they are..

So it didn't take much work to come up with a way to install the plastic wheels, as well as correct the flexing hull.

ausf

Is that a plastic housing that the metal swing arm sits in?

If so, that's a big fail in my book. The metal hull is rendered useless if that's the case. It's like coupling two metal chain links with a plastic shower curtain ring.

YHR

Yes that is exactly what it is. I have never been a fan of the metal inserts inside plastic, however, I took a leap of faith when I bought this hull, as I was intrigued with the gearing setup.

I didn't notice this at first I had no wheels to fit this chassis. Once I started fabricating the axle posts and playing around , up close with the suspension arms, I noticed the how the suspension flayed out with weight. That is when I took a close look at what was happening around the suspension arms. My disappointment at the discovery of this flexing issue, has been resolved with some epoxy, When they fabricate these hulls they should add this gluing to the assembly process. As can be seen in the second picture once the epoxy has cured there is zero flexing. Personally I wouldn't write this hull off for this, as the fix is easy and within every ones skill set

So like so many things in this hobby, we have to resort to some modifications to improve on what is being delivered. Yes even Tamiya has some issues that need improving.

This flexing could be why Taigen decided to copy Mato and go with a full metal hull for the Sherman., I have two Mato metal hulls and they are solid as a rock. You could stand on them. I wouldn't do that with this hull.

ausf

You're right it's a simple fix, but I'd worry about that plastic sleeve oblonging over time. The point of metal is out the door once you have a weak material in between ala 'you're only as strong as your weakest link'.

I'm not one to insist on bearings on slow moving suspension parts, but at least a bushing is in order. A couple of hard impacts on the roadwheels and plastic is gonna crack, especially in the cold, even if repetitve motion against metal doesn't get it first.

Tamiya uses plastic over metal tubs, but not on anything mechanical. All the susension connection points are metal screwed to the aluminum hub, the plastic is merely a cosmetic shell.

YHR

Agreed, The suspension does screw into a plastic post, and time will tell how big of a weakness this is. You can see in the top picture this issue.. However this is under full deflection, and frankly I don't think this suspension would ever be witness to this much load in normal operating. The epoxy bond removes this flex and the cyclic stress that the post would have been under without the bonding. I think this will be OK. I typically don't fix things anymore until they have proven to be an issue. So with this I will take a wait and see approach. I doubt very much that this will fail.

This is something to be aware of for sure

Cheers

ausf

I didn't anticipate the amount of lateral stress on that pivot point when I did the Trump conversion. I assumed it was a short pivot, plastic would hold up, it worked fine around the shop. 6 out of 10 broke the first battle day, so I rebuilt with brass and haven't had any trouble.

Using epoxy definitely helped strengthen the areayou're probably okay.

As you say, time will tell.

Strato50

Dan the internal suspension spring itself is mounted to the metal, right? At least mathematically that point should take most of the 'weight' :P

YHR

No the spring is enclosed in the plastic boxes you see in the picture.. For every action there is a reaction, and the suspension pivot point is subject to these reactive forces, and on full suspension deflection you can witness the plastic deflection in my picture.. As delivered there is MORE flex on the area surrounding the suspension then there is on a Heng Long plastic tank.

So you will have the suspension flaying outward on this hull more then you would on a Heng Long hull, unless you do something to strengthen it. For me binding the plastic to the metal using epoxy was the answer.

YHR

If a person had a cast metal block that was attached on the hull as I have shown in this diagram, the problem would go away, This block would be attached by screws from the outside , through the plastic and then terminating in the block. This block would be bored and threaded to accept the accept the pivot arm screws. This would result in a very solid suspension.

So in reflection, my comment about this being equal to a Tamiya offering was a little premature. I think Tamiya would have done something similar to my diagram.

Strato50

Yea, that is odd then. What DOES the metal tub support then? Hmm..

I'm not sure if anyone here at the club has ordered one yet I'm still eager to get my eyes all over one :P

Panther F

I agree... maybe a big costly purchase I avoided.

My WSN's are looking pretty good now.




Jeff

Max-U52

I could probably make you a set of those metal blocks on the Bridgeport at work if you need them. I'd need a bit more info first, but if you want to collaborate and give it a try I'm on board with that. On the other hand, your epoxy fix is working nicely so why fix it again? Either way is good with me, it might be fun.

ausf

Judging by what they've done previously, you're probably right, they'd have metal pieces that bolt to the aluminum hull, most likely the spring enclosures would be metal too. And they'd provide the bronze bushings, hardware and pre-tap too.

I doubt they would use a plastic hull 'skin' at all going by their latest models, just provide the front, rear and side suspension details like stops in ABS that bolt in place.

Panther F

It's going to sound as though I am picking a fight, but I'm not. I was under the impression it was ALL metal. So are the out-drives housed in plastic? And the gearboxes are attached to a metal pan?

YHR's fix only attaches the plastic to the metal but doesn't address the anchor point. BTW... I thought this was all metal?

No comparing to this or that, this is a week point and clearly not worth buying only to have to re-engineer something else there.


I thought this was all metal?





Jeff

FreakyDude

Oh do you mean in comparison to the other metal lower T-34 that is available? Or do you mean this part needs to be re-worked/engineered in comparison to every other tank part that is purchased out of a box and is used without any changes?
The lower is metal, it has plastic coverings on the sides of the metal lower pan. The suspension springs are just way to strong as it takes a lot of force to compress them fully, that pressure pushes back on the suspension arm causing the plastic cover to bow out. Reason for this is because their is a plastic sleeve that goes into a hole and the suspension arm is screwed into the sleeve. The plastic cover bows out about 1/64" pretty miniscule, an easier fix would be to put a C clamp on the plastic sleeve, hull interior.
This issue is a non issue as time will prove.I haven't seen or heard of anybody with a Taigen T-34 having any issues period.

Max-U52

Curtis, did you get my PM? I know there's been problems with those lately. I answered your PM about volunteering for guinea pig duty.

Panther F

I'm ALWAYS available to look it over and see if it is indeed an issue.

Judging by the video I stand behind my conclusions.




Jeff

MAUS45

I think a better fix woud be something like this part? It is what tamiya uses tohold the swing arm in place so it does not flex away from the hull. This paticular part, shown in the photo I attached is for the tamiya Jagdpanther. The Panzer III metal/plastic hull has these. Not sure if the Taigen KV-1 or Tiger I and Tiger II have them.

FreakyDude

Double checking I have all the parts I want for the set up. Should be able to reply on Sunday.

FreakyDude

Sold a few T-34 tanks so far and a few T-34 lowers, No problems. Seeing as how I have seen both, run both and have both I think that is better than a video and I stand by my conclusions. For either of us only Time will tell the tale.

Max-U52

Sounds great, I'll be looking forward to hearing from you.

YHR

The outdrives are done very nicely, and they are all set in a metal casting. Since I bonded the plastic to the metal the flex issue has been cured. It could have been engineered better, but I think the epoxy fix is easy to do and it works. However this is a bit on the expensive side.