Heng Long Challenger 2.Metal Tracks and Sprokets etc.

[zooma]

When I first started back to r/c tanks I ordered a Challenger 2 from Toucan Hobbies as it came with metal tracks 360 turret rotation etc, but it turned out to be a bit of a nightmare. When the expensive Toucan delivery charges are added to the cost, it was certainly NOT a bargain - but far worse was to come!

Lots of problems followed starting with a VERY long delay waiting for Toucan to deliver my tank (no paint available at that time due to Covid), and being charged import duty and vat weeks BEFORE the tank arrived due to a cheap non working voltage checker (that I did not want) being sent to me as a "gift" due to the long delay waiting for my tank to be delivered.

This "free gift" was invoiced at the full price of the tank (including delivery) and this generated a bill from HMC to pay around £170! - weeks before the tank itself was delivered! A call to HMC to protest at the cost of the tax bill received the reply that this was due to the paperwork that had been supplied with the so-called free gift, suggesting that its value was high enough to require these taxes to be paid. Any enquires about the paperwork should be directed to the seller - but the tax bill had been generated and so it had to be paid - without fail!

Surprisingly, Toucan Hobbies could do nothing to help rectify this incorrect paperwork. This was very disappointing as I always found deliveries of small parts and spares from Toucon to be very good,

When the tank eventually arrived, it run very badly suggesting that the metal tracks had some tight links, so I wanted to remove them so I could check each link. The right hand metal drive sprocket was also loose but I can't remove it as the metal hub cap has been glued-on VERY WELL.

The exhaust covers on the Challenger 2 are also the filler points for the smoke fluid. These had also been super glued down and could not be shifted. In the end I had to cut them off and re-establish the socket with a Swiss file so I could fit a pair of new replacements that I bought from HAYA (shame I didn't know about HAYA or Forgebear in those early days - it would have saved me a lot of time, hassle and cash if I bought the tank from them).

With all the problems, excess costs and delays, this particular Challenger 2 did not exactly endear itself for me, so I dumped it in a corner while I worked on other things that were not so frustrating......but I have just dragged it out again as I need to get some use out of it - but first I need to fix it.

I need to find a way to remove the metal hub caps from the sprockets so I can access the screws that hold the sprockets onto the gearbox axles. The hubcaps have a hole in the middle, so I found a close fitting metal bar (a 2.0mm hardened steel hex driver) and hoped to be able to gently lever them off by gradually working my way around the hub - but they are absolutely SOLID and did not move at all.

At the moment it is looking like I will need to destroy the hub cap (drill it out?) to access the retaining screw. I don't suppose I will be able to replace this metal hub cap, but the tank won't run as it was delivered, so I have no option other than to try and remove it by any means possible.

I am tempted to dump this (very expensive) and very frustrating tank back in the corner again, but I do want to be able to use it - so those hub caps need to be removed, and the metal tracks made to work or (more bad news) replaced with a new pair of tracks that do work.

Has anyone else ever bought a tank with so many problems that they wish they had never bought it?

[zooma]

I finally managed to lever-off one of the hubcaps from the alloy drive sockets using my 2.0mm EDS hardened hex driver, but my attempt to do the same with the second alloy hub cap resulted in snapping-off the hardened hex driver shaft ! That gave me some idea of just how well glued into the metal drive sprockets these hubcaps really were as the shaft was inserted into the cap as deep as it could go - and was not being used just on it's end point?

As a last attempt before drilling out this second hubcap, I screwed a self tapping screw into it and then levered the screw shaft as I drove it into the cap further and further until it came out. I may cut a 3mm screw thread into these caps while they are off so I can make it easy to remove them again in the future by using a 3mm cap head screw as an extractor when needed.

The drive sprocket fixing screws were at last accessible, but they were also super-glued ! These 3 x 12 mm cap head screws were eventually removed using a 2.5mm EDS hardened driver. This tool did not snap!

Just to complete the misery, the drive sprockets had some super-glue on them as well (!), so they had to be levered off of the gearbox axles using a thin wide bladed screwdriver whilst turning the sprockets a few degrees at a time to give equal pressure all around until they were also persuaded to release their grip and were removed from the axles.

Once the drive sprockets were removed, there were some unavoidable marks in the PLASTIC outer bearing. As far as the running gear is concerned, I paid for a top spec tank with metal gearbox, metal suspension arms, metal sprockets and return wheel, metal tracks with rubber pads...and it was supplied with only the kit standard PLASTIC axle bearing, I was even less impressed when I discovered this!

As I was on a bit of a "downer" with his tank, I looked at the grey plastic gear covers with some suspicion and was relieved to find they that actually did have metal gears hidden underneath - so at least the gearboxes were OK.

IMHO there can be no doubt that the builder of this particular Challenger 2 had no idea about actually running an r/c tank. Super-glueing the removable exhaust filler caps down (so they could not be used) and then super-gluing the metal hubcab covers on along with the fixing screws (and the sprockets onto the shafts) actively prevented any sort of maintenance that anyone running these tanks will need to do from time to time.

This feeling was not improved when I tried to remove the metal front hub caps from the metal return wheels. No prizes for guessing that they were also super-glued on, and with nothing to grip these tapered shape (like a witches hat) hubcaps, I had to lever them off using a lot of force with a thin bladed screw driver whilst rotating them to give equal pressure all the way around until they were also removed.

The above action eventually removed the front hub caps, but needing so much force on such a small area with no good secure pressure location point caused the thin (sharp) screwdriver blade to slip whilst under a lot of pressure. Fortunately my left hand index finger prevented this fast moving blade from travelling too far (!!!).

The blade buried itself deeply into my finger giving a fitting end to this painful experience - all of which could have been avoided if the model had been put together with some thought given to the tanks owner's need to actually use it!

I did take a colourful picture of my "stabbed" index finger - but decided not to show it here!

Not Impressed!

[zooma]

As I take some time to check the rough running of this Challenger 2 and inspect every link of the metal tracks, I will fit a cheap pair of plastic tracks that I bought from HAYA and give it a run with these fitted to see of all the blame lays with the metal tracks - or if I have something else to worry about!

Whilst checking the supplied metal tracks I notice that they are the cheaper single point type and not the better twin pin type that would articulate better.......again not the best for the price paid for this tank!

[zooma]

Single Pin Metal Tracks that came on this Challenger 2.

9595D57C-E317-4741-9F67-EB11500C782C.jpeg (1.01 MiB) Viewed 2589 times

On inspecting the Single Pin metal tracks (with rubber pads) that were supplied with the tank, I have found them to have no tight spots - every link moves freely, so maybe they do not fit onto the metal drive sprockets as well as they should?

I will see how well the tanks runs with the plastic tracks fitted - hopefully better than it does with these metal tracks !

[Pavel]

It's probably inconvenient to search for what you wrote, but many have already been through this...
I removed the caps by making a fork, pried the cap up and applied force to remove it, the sprocket cover has a groove into which I threaded a watch screwdriver and also pulled it out with a lever.
Further, the tracks seem to move normally, but I found several that cling to each other with flashing, a little filing and everything will be fine.
And the main thing!
The cast teeth of the wheel do not match the pitch of the tracks, I filed each tooth with Dremel (Prokson), like a good dentist.
I put the wheel on a nail and rolled the track under its own weight and while it rolled freely on the teeth.
If you don't believe me, look carefully, turning the track on the wheel...
And one more thing.. these rubber bands have a nasty habit of flying off, I often collected them after a race...

[zooma]

Wires from the board to the motors marked ready to connect to the RED motors.

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I thought that I would convert my Challenger 2 to run on the RED motors so I removed the two gearboxes and was amazed to find that the gearbox axles had only had the kits original PLASTIC axle bearings.

With an expensive model like this that came with Metal Gearboxes, Metal Tracks, Sprokets and Drive Wheels etc, failing to upgrade these plastic bearing seems like "penny pinching" and not in keeping with the otherwise well specified fitted option parts.

HAYA do not have any bearings in stock to fit the Challenger 2 and I cannot see any on the Forgebear site either, so my two local UK suppliers cannot help me. A return to the Toucan site found these bearings to fit the Challenger 2 available form stock!

I labelled the left and right motor wires to the boards with masking tape to make it easy to connect-up the new RED motors correctly.

[Pavel]

I installed it myself 12x8x3.5
And sealed it with an oil sealing cap...
Half an hour's work....

[zooma]

The standard drive motors were removed and replaced with a pair or RED motors to give a little more power.

The standard motors were held in place with a pair of cross head screws (no sign of any thread lock). The RED motors were fitted with a pair of 5mm stainless socket head screws to hold them in place and each was given a small dab of thread lock to secure them.

With no ball raced axle conversion sets for the Challenger 2 being currently available, the gearboxes were re-fitted into the hull. The close proximity of the RED motors end plates to the metal side walls of the gearboxes was noted and some the plastic shims will be made and pushed in-between them to stop them touching (and shorting out) when in use.

The tracks were checked and every single link moves freely so they have been re-fitted ready for testing. Any more problems and they will be replaced with the plastic tracks until I find out how to adjust the teeth on the sprockets (if necessary).

The drive wheels and drive sprockets have been re-fitted without their hub caps for the time being and until I known that the drive train is working nice and smoothly. The drive sprockets are now retained with a new pair of M3 x 12mm stainless steel cap heads that can be held firm with a "soft" thread lock once I am happy with the drive train.

[Meter rat]

Oh dear, Mr Zooma. Welcome to the wallet emptying of the world of Challenger. I to have been through similar as you with my very own problematic Challenger. If you need any help you know where I am.
For the drive shaft out put bearings. They are readily available from bearing factors, and are sold for roller skates and skate boards. They will also be cheaper. Pavel has given you the size. Red motors in these make the world of difference in these large models. As you have found they are a tight fit, with very little clearance.
It would be well worth your time to brace the lower hull. I found that to get the metal tracks to the correct tension, the hull would distort, and flex, causing alinement problems , which caused the tracks to come off. Since bracing the hull, I have not had any issues with tracks coming off. I do run mine hard and fast, on S3 batteries.
Fail all else, it could be donated to the Dunoon sanctuary for unwanted Challengers.

[zooma]

I installed it myself 12x8x3.5
And sealed it with an oil sealing cap...
Half an hour's work....

That looks good Pavel,

I can source bearings that size locally, so would you like to share your fitting method please?

Your middle picture looks like you have fitted two of these narrow ( 3.5mm) bearings together and used them as a 7mm wide pair.

Did you drill out the plastic moulded bearing from the hull (the part shown in my picture with the 3908 number moulded in it) completely and machine a spacer to hold the new bearing and then glue it in?

The end result looks very professional - nice work!

Bob.