Used Challenger Strip and Rebuild.

[zooma]

Sorry I don't have any practical experience of owning or driving a Heng Long Tiger 1 Pavel - but I am surprised that they are more troublesome for "throwing" their metal tracks off than the models with the longer chassis,.

The only frequently reported track throwing problems (with Heng Long Tanks) that I have either encountered personally or been made aware of are those with the three long chassis MBT that I have named here already.......but that could be because my current interest is with Modern MBT tanks and so I don't get to hear so much about the shorter WW2 Heng Long tanks performances and problems.

Previously I have owned and driven several WW2 Tamiya Full Option Tanks - (including quite a few Tiger 1, Sherman and King Tiger) over the years since they first came out, and none of them had problems with throwing off their tracks, but these don't really compare with the long chassis MTB tanks from Heng Long that are the subject of this discussion.

Interestingly though (and on a very similar note), the ONLY Tamiya tanks that I have had any problems with concerning their tracks is again with the LONG CHASSIS Leopard 2A6, (I still own and drive three of them!).

Like so many others I have found that they just do not drive very well until the plastic suspension arms are replaced with metal suspension arms as they just twist and fracture and break-off causing knock-on problems with the tracks. These tanks have a fairly rigid "metal box" chassis so the strain (and deflection movement) is taken on the suspension arms until they are strengthened by replacement with the metal option arms.

I also note that Tamiya have just released their latest version of this same tank but with cosmetic changes to make it the later model Leopard 2A7 - but it now comes as standard with METAL SUSPENSION ARMS - about time!

My MTB fleet include the just mentioned Tamiya Leopard 2A6 tanks - all equipped with various metal option parts - (ALL of them with metal suspension arms!) and a Heng Long Leopard 2A6 as a direct comparison.

The Heng Long Leopard 2A6 is an all plastic tank that runs very nicely on its plastic tracks - probably because it is a much lighter weight and so the chassis deflection is hugely reduced and is why the tracks stay in place so well. It will be interesting to see what happens to this reliability as weight is added with metal parts and metal tracks in the future!

The HL Challenger 2 tanks are the ones that I am working with at the moment including this 7+ years old original that has been very well used (without any chassis reinforcement) but it has not be subjected to extreme terrain with mud and rocks - yet!

My HAYA Chieftain and Centurion tanks are interesting as they have a moulded-in lattice work (like honeycomb) finish that can be seen on the inside of the chassis moulding . This does help to strengthen the chassis and reduce the amount of flex - but again I have found that the Chieftain tanks both run better with the lighter weight plastic tracks that help to reduce chassis flex.

I have no option but to run heavy metal tracks on the shorter HAYA Centurion tanks because I am not aware of any lighter weight plastic tracks that will fit them - but they have a shorter wheelbase and I am hoping that this will help to reduce any track throwing problems.

Lastly, I have my Heng Long T90 that is a basic lightweight all plastic tank that runs very nicely. It has a shorter chassis and than the Challenger 2 tanks, but again it will be interesting to see if anything changes with the addition of metal parts and tracks in the future!

Basically I have never tried running a longer Heng Long MBT tank with a reinforced chassis and I am looking forward to testing it against my others that do not have any form of chassis reinforcement so I can see the differences for myself and form my own conclusions on what I see.

What I am very much aware off is that the lighter weight all plastic tanks (with plastic tracks) run much better than they do when the weight is increased with the addition of metal drive trains (sprockets, wheels, rollers etc) and metal tracks.

When weight is added the moulded plastic chassis tubs start to flex and twist more (easy to see and understand) and this deflection can be the cause of tracks to be thrown off.

My experiment with this one model with a reinforced chassis is an attempt to reduce as much of this chassis flex and twist as possible to help stop or reduce the deflection that causes these longer chassis models to encounter problems keeping their tracks in place.

If it works then I will be encouraged to add chassis reinforcement to some of my other tanks (if they should have problems keeping their tracks on), and if I do, I may try making an integrated wooden structure to the inside of the moulded chassis - or even try a "poured-in" resin reinforcement like I saw inside Tom's Abrams and Challenger 2 tanks as that seemed to be working as well.

[zooma]

I am enjoying this build a lot. Your chassis brace is overkill even by my standards. A link will definitely need to be taken out of the tracks.

Thanks Ian ,

It was your Challenger 2 build and running video that has inspired me to have a go at preparing this old used Challenger 2 to be able to run on exceptionally rough terrain - and survive - as your does so well.

Thanks for your ideas and guidance.

If everything works as well on this Chally 2, then the ideas may well be transferred to The Rat Catcher project that I will return to working on once this well worn tank is back up and running again!

Bob.

[Pavel]

I didn't drive on parquet...
the entire chassis is metal

[zooma]

The caption to your picture (of a T90 !) says "the entire chassis is metal".

For somebody that has argued against chassis reinforcement - an entire metal chassis is an expensive (but very nice) over-kill Pavel. Have you fitted an alloy chassis to your Challenger 2 as well?

By comparison, fabricating a chassis reinforcement from angle alloy is a simple construction that anyone can achieve at very little cost that does not take much time or need any special tools to make or fit.

The simple frame that I have bashed together can be ADJUSTED (or removed) quite easily to give more or less flex or twist by making simple (cost free) changes to its rigidity.

If I can get the amount of chassis control (that I think I need) from a frame made out of scrap angle alloy (like mine has been), I will be very happy as it would be something that I can replicate on any tank at any time for almost zero cost.

The well used KISS (Keep It Simple Stupid) phrase sprung to mind as I started to write this as chassis control can be added to a model tank very simply and for very little cost.

[zooma]

The electrics will be placed into the hull and tested next as I did not get on very well with it when I first acquired this well used Challenger 2.

The circuit board that came with the tank is a TK24 -CH that does not have an S.bus connection and I had trouble "calling-up" the various functions when I wanted to use them.

All the functions worked OK and the board produced an really excellent Challenger 2 engine sound, but finding where to find any of them on the HiTec 6 channel transmitter was not easy and could not be replicated the next time that I tried to repeat the process.

The right hand stick unit worked well every time to drive and turn the tank, but the left hand stick seemed to suffer from overload as every other function had to be found on it.

[zooma]

As I refit the electrics into the hull I am going to change the HiTec radio for a used FlySky FS-16 (that I bought here on rctankwarfare) because the HiTec receiver does have an sbus connection, but the FS-16 receiver does have an sbus connection.

My TK24 board does not have an sbus connection at the moment, but I can send it away to Clark to get it added, so changing to the FS-16 radio will be slightly more future-proof and can work with or without the sbus connection.

Changing to the FS16 radio keeps my options open, but for now I will still have to try to find out how to get the TK24 board to access all of the non-drive functions from the left hand stick unit , so I have decided to keep it simple to start with by fitting it into the hull as I learn how to use the new to me FlySky transmitter

This will let me drive the hull and check all of the drive train before adding the top deck and turret.

One of the first things that I will check is the track tension. The pictures shown on here suggest that it may need link to two removing, but I have not checked it since the chassis rails have been added, so some of the slackness could be caused by the plastic hull sagging under the weight of the metal drive and heavy tracks?

[Pavel]

No, dear colleague, I have not reinforced any chassis!
Once, having bought into the admonition of colleagues, I bought a homemade chassis for the T-72 made of 2 mm steel, which needed to be covered with cut panels from a plastic chassis.
I did not engage in this stupid activity, and the hull is lying in my attic, no one wants to take it from me even for free....
Everyone checks the torsional strength of only the lower part, but once you install the upper part and try to twist it together, you will understand that this is not realistic.
If you say that magnets will not create strength, then look at how I did it...
And you are unlikely to be able to move the hull even a hundredth of an inch...

[Meter rat]

Ok guys. One person’s meat, is another person’s poison. Pavel if you find your Challenger runs well without a brace, then that is good. If Mr Zooma wants to install a brace, then that is good also. Mine ran better with a hull brace, and has eliminated the tracks coming off. Each of you has built your models to suit your requirements, neither of you are right or wrong.

[Pavel]

I said that EVERYONE has the right to their own opinion and there is no point in challenging it in our company.
I respect everyone's creativity!
I am simply sharing my experience....

[zooma]

No, dear colleague, I have not reinforced any chassis!
Once, having bought into the admonition of colleagues, I bought a homemade chassis for the T-72 made of 2 mm steel, which needed to be covered with cut panels from a plastic chassis.
I did not engage in this stupid activity, and the hull is lying in my attic, no one wants to take it from me even for free....
Everyone checks the torsional strength of only the lower part, but once you install the upper part and try to twist it together, you will understand that this is not realistic.
If you say that magnets will not create strength, then look at how I did it...
And you are unlikely to be able to move the hull even a hundredth of an inch...

The caption to your picture (of a T90 !) says "the entire chassis is metal" - that's what threw me - I thought you really had a tank where "the entire chassis is metal"......

What I do like is your alternative method of controlling the chassis movement with a combination of large high strength magnets and carbon fibre location pins that look like they are positioned to engage in the original screw hole turrets. Nice idea.

I can see how the locating pins can be inserted into the existing screw hole sockets to give a good positive alignment, and (with good strong magnets) this would help replace the rigidity that is lost when the tank is being run without the original screw fixings.

When these original screw fastenings are replaced with magnets alone, most of the original chassis control is lost as the magnets allow some "movement" that the screws would have been more likely to arrest.

What you have achieved is to return the tank to its original monococque construction where the top half of the tank (deck) provides an integral support to the lower chassis so that it can control chassis flex naturally - whilst retaining the benefits of a quickly removable top to give easy access inside the tank.

As I said - that is a nice idea.

I would like to try your idea on my next "long chassis" tank project as I think it will work quite well - but its effectiveness does rely on the upper hull moulding being nice and solid and not having any flex in I

As I have another Challenger 2 "on the stocks", I can build it to include your chassis fixing ideas - not just another long chassis tank - but one that is exactly the same as the one that I am currently working on here with an alloy frame to control the chassis flex.

One thing I think we can all agree on is that IF the chassis can twist and flex, it is unlikely to help keep the tracks aligned correctly.

How we achieve this (after we remove the screws that hold the upper and lower hull halves together) needs some good solutions - and now I have two good idea's that I would like to try - and I will enjoy testing them BOTH.

The best part about being a member of this forum (as far as I am concerned) is that is provides the opportunity to LEARN from the efforts that have been made by others, so I will never close my mind to other peoples ideas or dismiss them - I prefer to keep learning!