Trouble fitting PDSGB motor into Challenger 2 hull

[T9FURY]

Hi, I have just bought a PDSGB motor from DKLMRC and just trying to fit it in my HL Challie 2, but I am having issues with the hull mounting posts.
In the image below you can see the first problem I have. The hull screw mount has a little stem that sticks up preventing the motor mount from sitting flush. I was thinking of just filing it down. But I know on the original motor it prevents it from sliding about.



My second problem shown in the image below, the hull mount is too close to the motor mount wall so I can't get the screws in straight. I was just going to file out the plastic fill between the hull screw mount and the stem shown in the image above and just superglue some Tamiya circular beams in there and make some new screw holes in them but not sure if it would be strong enough.



I thought I would get some advice before I start butchering the hull. Maybe there is an easier way of doing it, or is there a specific motor mount that is sold for the Challie 2 and the supplier have sent the wrong one.
Another issue I have is the 2 little black grub screws that hold the drive cog onto the drive shaft are missing, I have emailed DKLMRC but as it is the Chinese new year they can't deal with it until they are back, so I was wondering if anyone knows the size of them (thread and length) so i can source them out locally.

Cheers
Mick

[MichaelC]

Mick,

I am not too sure if this is the right way of doing it, but I actually mounted mine slightly off center. As you can see in the picture, I use one of the nob to hold it and grind out the other one and use a small screw in place. You can do that with the DKLM plate because the shaft length is flexible, i.e. you can mount one shaft in slightly different than the other one since it is adjustable and just tighten via the grab screws.

[T9FURY]

Thanks for the quick reply matey, sounds like a plan, so just to confirm, you have only 3 screws holding the plate down right? I presume you have had no stability issues?
I'll wait to see if anyone else replies so I cover all my bases but if no one else has another solution I will go with your method and see how I get on. You way hasn't resulted in any serious butchering as well, so I like the sound of that.

I don't suppose you know the thread size and length of the 2 little grub screws that hold the drive cog on the drive shaft?

Another question, it looks like you have cut out the battery housing as well and put some sealant in there, is that correct?

[MichaelC]

Mick, if you look closely you can see where I have grind off the nob, I put in a very small screw to hold it in place as well. It is mean to be a new "nob" rather then another mounting point. Otherwise, that is it with the two screws (The third one you see is actually the mounting screw for the gearbox). I haven't driven the Chally very roughly outdoor yet but no problem so far.

I had a long discussion with Carson (In person no less as I was visiting) and the reason the plate doesn't necessary fit every tank perfectly is because if you think about it, Heng Long basically can play with the location of the mount point differently in every tank, depended on the length of the gear shaft they choose for that particular tank (i.e. long or short shaft) and the actual width of the tank. Because the way PDSGB is designed, it simply cannot have a mount point for every single Heng Long tanks because of that.

I think the grab screw is the standard one that you find in all of the Taigen tank swing arms and any brass gearbox shafts. I can check it but it won't be accurate. Did you check to see if it is screwed into the drive gear itself ? That's where mine was and it took me a little to realize it.

[T9FURY]

Yeah so 2 of the screws (nearest the battery compartment fit ok with the provided screws, you use the left hand stem to hold it in place with NO screw there, you filed down the right hand stem and just use the mounting screw with the hulls own mount. I thought you may get issues on that left side what with it not being screwed down. If you do test it can you let me know how you get on with it over rough terrain? I'll probbaly end up doing it this way myself and if it is not secure enough on that left side I will go with making a new screw mount and hope that holds.

I think the grab screw is the standard one that you find in all of the Taigen tank swing arms and any brass gearbox shafts. I can check it but it won't be accurate. Did you check to see if it is screwed into the drive gear itself ? That's where mine was and it took me a little to realize it.

Lol, what a dumb ass I am, they are allen key grub screws so when I first looked in them they just looked like two dark holes, normally grub screws are phillips heads. I put a torch to them and they are sitting deep in there, you can barely see them, lol. by the way I do wear glasses.

Thamks for your help mate, guess I will be fitting that Sunday if the paint has dried on my metal running gear.

Mick

[MichaelC]

No problem Mick. By the way, the left stem mount is too tight and not enough room for the given mounting screw head also, so I have to use a new one with a small head so that it will go down properly even with the shift of the plate.

Sorry just saw the battery compartment questions.......... The hull was flexing too much so I pour resin to strengthen it after removing the battery compartment.

[MichaelC]

Hey Mick now that you mentioned it I try pushing in on the sprocket and it does flex a bit, so I think I will change how I mount it. I will grind out the two nobs, center the plate, and then drill two new holes in the chassis to screw down the plate using the mounting screws beside where the nobs are. Will let you know how I make out.

Ed. This is what I did. Since I resin the lower, there is enough there to pre-drll and then use the mounting screw from the kit to fully mount the plate onto the lower.

The plate is now centered on the lower and the flex is gone. Now you don't have enough to drill and mount the screws, you can also try this (I am thinking of getting a set as well). I think you will need the 8.08mm one since the axle on the PDSGB is slightly larger than the stock 7.99mm. I try measuring it and I keep getting 8.04/8.05mm and not 7.99mm. If you use this one then I don't think you will to screw in to the extra mount points as the support will hold the axles in place.

http://www.rctank.de/Challenger-2-axle-supports-

[T9FURY]

Cheers for the feedback matey, I think I will do something similar, grind out the two stems AND the little wall of plastic in there but I think I will superglue some Tamiya circular beams in there and drill screw holes in them, I will probably also make them more secure using some sort of epoxy resin around them.

Not sure if I will bother with those axle supports, while I am sure they will help support it seems like going above and beyond and I have already spent a small fortune on this and it is only my first tank, lol. I'll defo keep he link handy though just in case I change my mind.

What is the name of that resin you have used in the bottom of yours? Is like a thick paste or is it like a clay that goes solid?

[MichaelC]

The resin I use goes solid, I can't remember what brand but if you goto craft store you can always get two part resin that either goes clear or solid white. After they harden you can drill/paint do whatever you want with it. It gets hot when you first pour it and you have to make sure there is no leakage or overflow into other parts of the chassis. Also, make sure the chassis does not have opening into the swing arm screws/mounts or you might get some of the stuck. Chally doesn't have that so it is easy.

[T9FURY]

And you did that because you removed the battery housing?