Amateur Build. HAYA Centurion KIT

[tankme]

If you were in the US I'd just send you my side skirt supports as I'm not going to use the side skirts. I'm going to cut them off for my Vietnam themed Centurion.

[zooma]

If you were in the US I'd just send you my side skirt supports as I'm not going to use the side skirts. I'm going to cut them off for my Vietnam themed Centurion.

Thanks tankme - that is a very kind thought. Fortunately I had a message from Andrew at HAYA this morning to let me know that the missing tyre and a side skirt support will be posted to me Monday morning.

Apparently the two metal axles for the rear return rollers have already been posted so hopefully they will arrive very soon. With some luck I should be able to get this lower chassis part of the build completed next week.

Good luck with your Vietnam Centurion build - let me know if you have had similar problems to the ones that I have had with your HAYA KIT build and if you have found any better solutions.

Bob.

[ongbenghui]

I also have a broken Bazooka Plate Support. I am not at all sure what happened, but one of these strong looking supports has "sheared-off" at its root. I have given all the others a god solid "tweak" to make sure they are OK and every one is "as solid as a rock" so this is a real mystery as the tank has not seen any action yet! Maybe this particular moulding had a slight flaw (?) but either way I need to ask for a replacement part.

I had the same problem that I broken one and decided to glue and reinforce the rest with JB weld eproxy on the edge. However, I made a silly mistake on the mount that I unfortunately damaged two of those mounting on the hull with some paint solvent.

In the end, I just given up all those plate support. They are are actually not needed for me, because the spacing on the side skirt is sufficient and the side skirt is pretty stiff.

But glad that Andrew will be shipping you all the missing parts.

[zooma]

Just a splash of paint needed ..and a rubber tyre !!

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The two metal axles that I have been waiting for arrived in the post this morning - and were fitted with the two rear track rollers just a few minutes later!

These axles (like the front roller axles) are a simple push-fit into the half-circular opening on the chassis so they can only be fitted one way.

Contrary to the online video (where the use of thin black screws appears to be suggested) I used the same 2.6 x 6 STS as I used to secure the same axles on the front of the chassis tub. The 2.6 x 6 STS are the most commonly used screws on the build so far.

Just a little paint on the roller (I will probably brush paint it later) and then I can test fit the tracks.

[zooma]

As the previous picture shows, the chassis had been left long enough to gather some dust (!) so once the rear rollers were fitted I couldn't wait to test fit the tracks (nobody will probably notice the missing tyre or the unpainted rear track rollers!) and it was very good to see them fitted.

I did find fitting the tracks a little more awkward than I had expected it to be - probably because the tracks are new and heavy and a little stiff - and because they had not been fitted before.

Lining-up the flat on the rear axle with the flat on the drive sprocket was made a little easier by drawing a line (with a felt tip) inside the drive sprocket to align with the flat that was out of sight on the inside when I was trying to fit it.

This helped quite a lot and made it a lot easier to fit the stiff new track in place.

The rear axle is tapped with a 3mm screw thread. I could not find any 3mm machine screws in the kit to hold the drive sprockets onto the drive axles, but I prefer to use cap head screws in any case so I found a pair of 3mm x 10mm stainless steel cap head screws and fitted them with a nice stainless "mudguard washer" (these have a slightly wider flange than a standard 3mm washer) as I thought they would make a better job.

As a matter of interest, I need to take the hub-caps off of my RTR Centurion to tighten the drive sprocket that has come loose (!) so I will take the opportunity to upgrade to cap-head screws on that model too - but I am dreading getting the hub caps off !



UPDATE. I had to remove the drive sprocket hub caps on my RTR HAYA Centurion as one of the drive sprockets has come loose, and, I will need to take both sprockets off when I have found out if the BLUE motors will give the better power that the tank needs - because then I will need to remove both drive sprockets, tracks, and gearboxes to make the motor upgrade.

Getting the hub caps off was not an easy job (as suspected) and was eventually achieved by levering away with a very thin flat headed screwdriver (working my way around the circumference little by little) and when enough of the dome headed hub cap was withdrawn from the drive sprocket casting to grip it, it was fully removed by pulling it out with a pair of flat nosed engineers pliers.

Minimising the damage to the tight fitting soft alloy hub cap castings when trying to get them out of the drive sprockets was again - not as easy as it might at first seem as the hub caps are dome shaped and are buried into the drive sprocket deeply enough not to offer a nice square edge to grip it with until prised out enough to expose it's edges.

I lost some paint when removing my hubcaps and also scraped into the soft castings a little - but once removed I was able to find out what type and size of screw lay hidden underneath it to secure the drive sprockets onto the gearbox output axles.

A loose cross head screw was discovered underneath, and when removed it was found to be only 8mm long!

The way I see it, I want as much screw threaded into the axle as possible to reduce the likelihood of it unscrewing in use.

I had already fitted the kit sprockets with 10mm long cap heads, but they had not "bottomed-out" in the axle's screw thread - so I experimented by screwing in 12mm long stainless steel cap-headed screws (with a "mudguard washer" to spread the load as evenly across the flat area of the socket recess as possible) and they did not bottom-out either!

There may still be some threaded axle left that could take an even longer fixing screw (?) but I am happy to stick with the 12mm long cap head screws for this purpose as this has already given me a 50% increase in screw length (over the factory built RTR Centurion) that should provide a much more secure fixing of the drive sprockets to the gearbox output axle - especially considering how much easier it is to tighten the screw with an Allen driver!

The chances of the drive sprocket coming loose again are now much reduced. Considering how difficult it is to remove the dome headed (soft metal) hub caps from the drive sprockets without damaging them - this has got to be a worthwhile upgrade IMHO.

Tightening the cap-head screws with a hardened tip Allen key screwdriver is much easier and more positive that trying to tighten it with a cross head screw-driver so I am pleased that I made the change. These (now upgraded to 12mm) will be given a small dash of blue thread-lock to keep them in place when I am driving the tank.

[zooma]

Having fitted the tracks I connected the motors (one at a time) to the small sized 7.4 volt 1800 mAh battery that came with my Heng Long T90 to make sure that everything was aligned correctly.

Each track spun nice and freely and the tracks stayed in place - so everything must be lined-up OK. RESULT!

I had feared that the tracks may not "run true" as when I looked at the two front alloy return wheels "head-on" from the front they appear to lean inwards at the tops - one side more than the other !

Having actually lost some sleep worrying about this and deciding that I could not not see any easy way to correct it (those large cast "plug-in" front axle mounts would not be easy to re-align) I eventually hoped that it was either a trick of my bi-focal lens - or it didn't matter!

When looking along a long length of strip wood (that is known to be straight) it always appears curved when wearing bi-focal glasses. I decided to blame my glasses for giving me the illusion that these two front wheel castings look to toe-in towards their tops........or it simply didn't matter!

Either way, the tracks ran nicely at top speed (fully charged battery - no speed controller) so as noted above - RESULT - I am super-pleased and will not loose any more sleep worrying about it!

NOTE. The hub caps for the drive sprockets will NOT be fitted until I am convinced that they will not need to be removed again! They are so difficult to remove (without damage to them or the paint) that it is not worth it at this stage. I will put some paint on the cap-head screws and "mudguard" washers to help camouflage them until the hub caps are finally fitted - but I bet when the tank is running very few (if anyone) will notice that they are actually missing!!!!

[zooma]

As previously mentioned - when I soldered some 16 AWG wires onto the BLUE motors I connected the red wire to the + terminal on each motor (marked with a red paint spot and inscribed with a + symbol).

Naturally with one motor on each side of the tank they will turn the tracks in opposite directions when both are turning clock-wise, so when I connected the battery to the motors the right hand track turned in the backwards direction, and the left hand tracks turned in the opposite direction (forwards).

I can easily correct this by reversing the wires in the XT60 plug that is connected to the right hand motor - BUT - should I do this or will the "Board" expect the motors to be wired "correctly" and convert the track direction as part of its function?

HELP please! I haven't decided what board to buy yet (probably a Clark board from HAYA with the pre-loaded Rolls Royce engine sound).

QUESTION - should the wires be soldered correctly ( as they are now - but with the tracks running in opposite directions) or should I re-solder the right hand motor to make it run in the same direction as the left hand motor?

[tankme]

The motors will need to be connected the right way for the control board to work right. Brushed motors in these tanks are neutrally timed so it really doesn't matter if the positive is soldered to the negative pole and vise versa. It's kinda why I always use some sort of barrel connection on my motors so that I can quickly change the polarity if needed rather than having to re-solder something. They make 4mm barrels and also they sell the Tamiya barrel connectors that are used on the HL boards:

https://www.amazon.com/Tamiya-50245-Sna ... C95&sr=1-1

[zooma]

The motors will need to be connected the right way for the control board to work right. Brushed motors in these tanks are neutrally timed so it really doesn't matter if the positive is soldered to the negative pole and vise versa. It's kinda why I always use some sort of barrel connection on my motors so that I can quickly change the polarity if needed rather than having to re-solder something. They make 4mm barrels and also they sell the Tamiya barrel connectors that are used on the HL boards:

Thanks Derek,

I agree that my choice of XT60 plugs was not the most "flexible" for this application, and although I always use XT connectors (all sizes) for connecting batteries to ESC, I have never used them before for connecting any motor to any ESC (or in this case a "board") in any model of any size. (I always use gold connectors for this job as the best and safest way to work - or no connectors at all if possible to direct to wire) ......but it did prove to be really handy for test running the motors and tracks earlier today

The truth is that I actually run-out of small gold connectors. I have plenty of the much bigger gold connectors that I use for my fast power boats etc, but none of the smaller sizes.

I usually buy my gold connectors from Hobby King as they have the best quality at the best prices, but their overseas shipping costs to the UK are way too expensive to live with and their UK depot is currently out of stock of them so I just bunged-on some XT 60 so I could test run the motors and the tracks - but the question about the motors direction of turn was important as I have never fitted any sort of "board" before and wanted to know.

I have checked all the other tanks that I have from Heng Long and HAYA and noted that every motor has the + positive red wire soldered onto the + red positive side of the motor - and is why I copied it......but then reason prevailed and questioned this as the motors face in opposite directions and so when they are both running clockwise they must be running in opposite directions.....

.....so, assuming the RTR tanks motors are correctly marked, I guessed that the "board" would be made to automatically take this into account.......but it also runs against everything I have ever done before (never fitted a board) and the temptation would have been to re-wire one of the motors so they both run in the same direction....but that would be wrong?

Electronics are not my strongest suit (probably worse than my painting skills) so I just wanted to check so I know what I am doing.......long before I solder or plug anything into a "board".

Stay safe - Bob.

ps. I just ordered 10 pairs of 3.5mm gold connectors from eBay this evening so I can use them to replace the XT60 I temporarily fitted for the motor and track testing. I will stagger the wire lengths ( as always ) so that in the event of any failure on the heat shrink - no bare connectors can touch each other. Old School "belt and braces" - always!

[zooma]

A big very green lump !

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I guess the next step is to start work on the Centurion "top deck" .

This is a large and substantial (very green) lump of plastic that I will paint as soon as possible (!) but not until after I have added any parts that may need glue so I don't have to rub the paint off again to achieve a good bond.

I did notice that when I placed this large moulded part onto the lower chassis that I had to pull open the sides a little so that the moulding could fit over the "Bazooka Plate" mounts! These mounts are pushed into their sockets in the main lower chassis moulding as far and deep as they will go (no gaps) so I think the sides of my particular moulding may be slightly warped (inwards) - but it is a nice tight fit and looks OK.

This top chassis moulding (top deck) will be left mounted onto the lower chassis more of less permanently as I work on it so it may slowly recover its shape as these side mounts push it back out to the correct shape (I am hoping for some "plastic memory" to help me out and remember the shape of the mould)!

Before that, I will screw-on the mountings that will secure the upper part of the tank onto the lower chassis tub....and maybe I will have a re-think about just how many top-deck mounted parts could be vulnerable to damage when I am fitting the turret assembly later ......hmmmm.........