RC Tanks Australia Forum

Ok, so my Chally 2 build begins. As usual my starting point is to remove the H/L electronics and plastic gearboxes, and replace them with Black steel gears, drive shaft supports, and IBU2 Pro electronics. Only a couple of hours in so far but here are some pics and details of the work done to date.

Here is the hull after the H/L electronics have been removed, all pretty easy on this one, even the 2.4Ghz rx was not glued in or fixed in any way.



The plastic Gearboxes were also removed, and axle supports for the drive shafts fitted. These are the axle supports for the Abrams from RCTank.de.



I fitted these on the outside by grinding away some of the plastic on the inside of the 2 large holes which the drive shafts pass through until these supports where a good press fit into the holes. I then glued these in place with gorilla super glue. They could not be bolted due to their proximity to the back of the sprockets As will be seen later.

Next new Gearboxes and motors were fitted. The gearboxes are 3.1 Taigen black steel boxes with bearings on all axles again from RCTank.de, and the motors are my favourite JP powers from Sussex Model Centre this time in 480 guise.



These gearboxes come with slightly larger sprocket drive axles than the H/L ones, so the sprockets had to be worked on to make them fit the axles, and to accommodate the larger allen bolt that Taigen use to secure the sprocket. The sprockets where than test fitted to ensure they cleared the axle supports. You can see in the next pick why the supports where not bolted in place.



Next M3 computer stand offs where used to fit the IBU2 Pro over the battery box, and the power lead, rear light, motors and receiver were connected up. I then used a NiMh battery to check the motors run correctly which they did first time, and then tidied up the wiring a little.



Thats pretty much it for now. I may get some more done this afternoon, and will post more as the build progresses.

Some more done.

Test fit of the upper hull to see if everything fits so far.



All good so on to changing the battery to 3s LiPo. The IBU2 Pro makes this easy. There are a couple of switches on the board to be changed, and swapping the plugs to the red 4mm ones I like to use. Although the IBU monitors the battery voltage I also add an audible voltage alarm so that I can hear it on the battlefield if the battery runs low. The 3600mah batteries I am using fit in the battery box on H/L tanks, so I left the box in place as it forms part of the structure of the lower hull and helps maintain rigidity.



In this shot you can see the LiPo alarm above the IBU with the lights on. Also the sound and smoke systems have been installed.



The sound and smoke systems follow my usual set ups. Here you can see the sound components which have been added. The viper remote volume control to the immediate left of the IBU on the battery box. this connects to the IBU volume control port, and a spare channel on the receiver. The red board to the left of the battery box is the amp. This needs a power supply, and is then connected to the IBU speaker port and the speaker. As you will also see the speaker has been uprated. The ones that H/L are now using are even more poor quality than their previous speakers. I get my speakers from here

http://www.tank-modellbau.de/k_eng_36/Speakers



The smoke system is based on a Tarr1 smoke unit. This is fitted between the gearboxes. There is a piece of plastic coated wire (paperclips) in each tube coming from the smoker. This helps to shape the tubes, and prevents them from creasing and blocking when the upper hull is screwed down.



The tubes that come with the Tarr1 are a smaller diameter than that used by H/l, and actually make a perfect fit when slid inside the original tubes. Here you can see the H/L smoke unit has been removed from the upper hull and the Tubes to the exhaust have been trimmed to allow enough slack that the tubes from the smoker can be slid inside them, but not so long that they will crease up when the upper hull is screwed down. The tubes from the lower half will slide about 3/4 of an inch into these tubes relatively easy.



Thats all for now, but more to follow soon. This pretty much completes the install in the lower half, so next will be the upper hull and turret

last update for today.

I spent the evening installing the turret rotation servo, which is now up and running. Again my usual method of attaching the servo to the upper hull, this time using a plasticard bracket I made up, and making sure that it fits the lower hull. In this instance the servo sits in the gap between the hull and the battery box.



More tomorrow all being well. I should be venturing into the turret 8O

Ok so today is turret day.

Turret removed



and the turret base removed, how many screws (10)



All the H/L gun elevation was removed as this tank will have servo elevation.



Although there is no recoil being fitted to this tank yet (maybe later) it will have LED gun flash in the barrel, so the bottom end of the BB gun was removed along with all the bb gun internals. The tab at the back of this assembly which hooked under the H/L elevation mechanism was also removed as this can get in the way of barrel deflection.




I am finding this tank very pleasant to work on so far, it seems very well thought out in how it is put together so parts fit and can be disassembled easily.

I used a micro servo for the elevation with a single arm which has a small screw in the far end of it. A piece of U shaped plasticard channel was glued to the side of the remaining portion of the bb gun mechanism.



The servo was then glued to the underside of the bb feed chute so that the screw in the servo arm is inside the plasticard channel. Initially I glued the servo directly to the bb chute, however when I tested the elevation this set up gave me limited upwards movement of the barrel. I added a slightly longer servo arm and added some packing under the servo to fix this which you will see in later pics.



You can also see that the LED muzzle flash has been added, thats the black and red pair. The white and red pair is the MG flash which is the only Turret wiring which was retained. The flash lead is short as it will plug into the slipring to give continuous rotation. The slipring wiring is shown in the next pic.



At this point in reassembly I found that the cross shaped moulding in the turret roof which originally held the H/L elevation spring in place would restrict the gun movement too, so this was also removed.
Next the turret bottom was screwed back in place, and the turret side of the slipring wiring was tidied into the bb gun housing and a cover for this was added. The hull side slipring wiring was tidied ready for the turret to go back on the tank.



You can just see here the packing I added to the elevation servo to improve upwards movement.



Thats it so far today, now need to reassemble the tank and test out the full set of functions. I will do a video to show this when I have it done.

Paul

Everything is back together minus tracks, and the electronics install has been tested. All is working well. This was a first try for the Challenger 2 sound set from RC Tank Electronics too. I may make a few little tweaks, but i like it.

here is a video showing all the functions and sounds.

Today I painted the tracks. I used Tamiya ZF-72 JGSDF Brown, and then added a wash of Mig ammo track wash in a 50/50 mix with white spirit. The tracks are the metal leopard 2 tracks with rubber tread pads which are generally available. I got mine from Tank Army. These are almost identical to the tracks used on the Challenger 2.



Just the lovely job now of sticking the rubber tread pads on. I will be using Gorilla super glue for this. It has a rubber compound in it which means it does not set brittle like most super glue does. Ideal for this application.

This tank comes with the standard H/L flashing MG barrel for the Coax Chain gun. I was not happy with that especially as the Coax in the Challenger 2 is a L94A1 chain gun which looks nothing like the H/L part. So while waiting for paint to dry on the tracks I set about replacing it. Here is the result.





It is made up from a piece of 4mm outside diameter tube, with 1mm diameter plastic rod used for the cooling fins and barrel. I know the fins should be a squarer profile, but I did not have any appropriate plastic strip available, and filing down the sides of the plastic rod left it looking too thin so this will have to do.

More to follow soon so keep watching this space.

Paul

Gun turned out well, does it have a LED flash inside? Could some F O cable do the same job for more flash effect?

Cheers
Gra

_________________
Gra's Heavy Tank Regiment
HL Tiger 1 - El Mod, Tiger 1, K T Porsche turret, Panzer III & IV, Stug G & E, Panther D,
Matorro KT, Jagdtiger and Sturmtiger, HL Sherman and T - 34, A7V (WIP)
Panzergruppe South Member

The tracks are now complete



and fitted




All is now running smoothly.

HOWEVER

Fitting the Leopard 2 tracks was not as straight forward as I anticipated. I had imagined that H/L would have just used there existing Leopard 2 tracks on this tank as they are so similar. However I was wrong on this. When it came time to fit these tracks they would not fit the sprockets. Comparing the Challenger tracks with a set of H/L leopard tracks I have has revealed that H/L do seem to have made a set of tracks specific to the challenger.

In this pic you can see the leopard track at the back is just under a mm wider. Both tracks are sitting on the same level flat surface, and have had the links tapped down tight. I put the white card in to give a consistent background.



I think the Challenger links may also be a fraction of a mm shorter too. sorry not a great pic.



I had to do quite a bit of work to the plastic sprockets to get things running ok. The back of each tooth was filed back to allow the wider links to sit between the sprocket rings. The profile of each tooth had to be adjusted slightly too in order to get the sprocket and track to mesh properly.

So these tracks will work on this tank, but not without quite a bit of work. I wonder if the aftermarket extras will be the same or if someone will produce a sprocket which works out of the box with these tracks.

On another note, I discovered that one of the sprockets I have has a tooth missing. I noticed this before trying any fitting of the new tracks, which means that this must have come from the factory like this. The tank has not been run by me prior to today, and I have only touched the sprockets to take off the old tracks.

I hope some will find this helpful.

Paul

Very useful Scalawag, seems HL is not cutting corners now with there tanks as it would have been so easy for them to use the Leo tracks and not go to all the trouble of a mm or 2 difference. Good to see so we have to check every time from now on and not presume?

Cheers
Gra

Ps the rubber pads look great

_________________
Gra's Heavy Tank Regiment
HL Tiger 1 - El Mod, Tiger 1, K T Porsche turret, Panzer III & IV, Stug G & E, Panther D,
Matorro KT, Jagdtiger and Sturmtiger, HL Sherman and T - 34, A7V (WIP)
Panzergruppe South Member