Used Challenger Strip and Rebuild.

[Pavel]

Don't forget about alignment, before I glued the bearings, I inserted an 8 mm shaft into it and into the gearbox, only then I filled it with resin, carefully - with a toothpick, drop by drop...

[zooma]

Outside hub

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Inside hub

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With the right hand gearbox refitted, the bearing was slid onto the gearbox output axle before being tacked in place with 24 hour Araldite.

With the gearbox left in place as an alignment guide overnight, the Araldite was allowed to set slowly.

The Araldite held the bearing in place firmly enough to allow the gearbox to be removed afterwards without being dislodged.

I ordered some JB Weld and the "Best Weld Metal Repair Glue" from Amazon. Two very similar products that looked like they would be perfect for the job, so the idea was to test them both and see which one was likely to work the best.

The JB Weld did not arrive until the day after, so I used the Metal Repair Glue (MRG) . The Amazon reviews and videos reassured me that the MRG should be a good product for the job - and I didn't wait for the JB Weld to arrive for comparison tests that I had planned.

Using the MRG I built-up the area around the outside of the bearing to replace the plastic that I had snapped-off when trying to open out the bearing holding space to the designated grove moulded into the hull side.

I also put a small amount of MRG around the inside socket to fill the small gap around the bearing to add more strength to the damaged area.

As the MRG began to harden, the blue masking tape covering the bearing face covers (inside and outside) were peeled off and the epoxy glue/filler was allowed to set hard.

When I later checked the piece of card that I had used to mix the two part MRG together, the unused residue had set rock solid with a very hard shiny surface. I was pleased to find no sticky surface residue at all (as is common with most epoxy fillers) on the fully cured MSG, so I was very pleased with this product that I had used for the first time and hope that its long term performance is just as impressive.

With the MSG fully hardened, both gearboxes were re-fitted and everything aligned and fitted correctly. The right hand bearing is now a solid fixture, so it was helpful to leave the left hand axle bearing unfitted to give a little more 'wriggle room" when refitting the two gearboxes back onto their mountings . Once in place and screwed down, the left had axle bearing was slid back onto the axle to complete the drive installation.

The tank had been run by the previous owner with no axle bearings fitted at all, so the loading on the Ultimate gearbox bearings would have been far higher than it should have been if the axle bearings were fitted.

The size of axle bearing chosen for this job was more or less dictated by the size of the openings that I had to fill in the hull, but the bearing is significantly bigger and more sturdy than the much smaller bearings that come with the alloy holders in the usual bearing upgrade kits, so as long as the right hand side repair hold firm, the Ultimate gearboxes should have a much easier life in the future.

The left hand axle bearing fitted with no problem at all after I had filed out the plastic to the moulded line that was the same o/s diameter as the bearing, and the flange fitted nice and flat against the hull side.

As long as the MSG repair holds-up this Challenger 2 should have a very robust drive train in place.

[zooma]

With the gearboxes cleaned and reinstated with new axle bearings, the next job is to take a look at the suspension.

Working from the front of the tank the suspension on the drive wheels is:

RIGHT ...............................................................................LEFT.
1.Soft. I will change this setting to Hard to start with..........1.Soft. I will change this setting to HARD to start with.
2.Soft. ...............................................................................2.Hard. I will change this to Soft.
3.Soft. .................................................................... ..........3. Hard. This one has a harder spring than all the others and needs a replacement spring so I can set it to Soft.
4.Soft.................................................................................4.Soft.
5.Soft.................................................................................5.Soft.
6.Hard................................................................................6.Soft. I will change this setting to HARD to start with.

The above adjustments have been made to balance the suspension on both sides of the tank. I admit to finding this a very tedious task!

L3 seems to have a harder spring than any other station and has not been given the Soft setting that it needs.

I did consider changing L3 with L1, but I have already "sorted" L1 (and it feels about right), so I don't want to swap again as L3 is harder than any other spring and would be best removed and replaced with one of similar strength to all the others.

[Ecam]

Love the refreshing on this worn tank. I don't know if I've ever witnessed a dirtier tank - then there is the foam walls/dividers and the duct/cloth tape...

[zooma]

As I re-fitted the drive sprockets, I took a good look at the "patina" that they had acquired from 7 years of use.

Should I clean them completely, or just accept that real dried-on mud may be more convincing than any painted on acrylic mud?

The argument in favour of cleaning them and adding any weathering at a later date, is that the "mud" or "dust" that I may want to add would be from a common theatre of operations, and those Challengers that I have seen so far in exercises on Salisbury Plain and BATUS tend to have a paler colour of dried- mud that has been accumulated on their tracks, wheels and sprockets.

I will of course be cleaning and checking everything before re-fitting it to ensure there is nothing won or broken that needs replacement .....but I am thinking that I will be giving all the wheels, sprockets, and rollers a good clean .....and that I prefer to add the 1/16 scale mud.

One thing that I will not be re-fitting is the slot headed screws that held these 4 part (two halves and two track retaining washers) onto the axles. I have already dumped them and used new stainless steel hex-headed 15mm screws for this purpose as they are much easier to tighten and loosen for regular maintenance than slot headed screws that would be much more likely to wear and burr with use........and the hex-head is much more of an engineered solution than a slot head as this is more of a wood working fixing IMHO.

[Herr Dr. Professor]

I am one who likes to "clean things up" for fear of damage. However, when I see the photos immediately above, I think of trying to match artificial weathering to the look of the sprockets and coating it all in a clear flat finish. Just an idea...

[Meter rat]

I would just leave them as is. It is part of what the tank is, and will constantly change over time.

[zooma]

As working my way around the tank I noticed than one of the return rollers was held on with an M3 cap head bolt with a thick brass "washer".

This stood out against the tiny small dome shaped screws that were used on all the other rollers - so I decided to take a look and see what was going on.

As I started to unscrew the cap head bolt, it more of less fell out in my hand revealing that the axle part of the metal casting had been snapped off, and this bolt had been used with a brass eyelet to cobble it together.

Just AFTER I had found and ordered the materials to make a better job of this repair (!), I recognised that these metal wheels were identical to the ones that I had recently purchased from HAYA to fit on my new Challenger 2 tank (!) so I contacted Andrew and was pleased to find out that I could have bought a full set of these alloy roller mounts for less cash that I had just spent on the materials to make a decent repair of the broken one (with enough material left over to repair all the others if they proved to be fragile in use).

I ordered a set from Andrew at HAYA to make a nice simple repair.....and the materials that I have ordered will come in handy for something.....hopefully....in the future....maybe.

[zooma]

Since I was talking to Andrew at HAYA about parts for my Used Challenger, I asked if he could sell me a spare suspension spring so I can replace the "over-stiff" one that needs "sorting".

It turns out that Andrew stocks and sells full spring sets for the Challenger 2 at a very modest price - so I bought a new spring set from him as well!

[zooma]

And a pair of these too......