Metal drive sprockets with anti-slip rings

[KH3DP]

The following relates specifically to a Heng Long 7.0 Challenger 2 with the standard metal drive sprockets and all-metal tracks, but I'm curious if it also applies to the M1A2 Abrams and Leopard 2A6. I know the drive sprockets are different for each of the three tanks, but I've heard the track is the same.

Recently ordered a set of metal drive sprockets with anti-slip rings off eBay from I-Love-Porcelain-Flower (Toucan Hobby?). They fit the drive axles fine, but I had a little problem getting the track settled on them. Finally got everything installed, but when I tried to run the tank, it would only move three or four links before jumping off the sprockets. Tried adjusting tension on the idlers, and even removing the idlers with same results. Even completely removed one sprocket and track, to move the track over the sprocket freehand, but same results. Finally noticed that the teeth are slightly larger compared to standard metal drive sprockets. Also noticed the center hubcaps are not interchangeable, but that part's not really surprising.

Has anyone else run into this?
Is this unique to the Challenger 2?
Are the metal drive sprockets with anti-slip rings only designed to work with one type of track (plastic, metal with one rubber pad, metal with two rubber pads)?

On a semi-related note, the drive sprockets with anti-slip rings came with washers. The tank itself did not. I can understand using metal washers with plastic drive sprockets. Are they needed with metal ones?

Thanks in advance.

[Sub]

Hi,
Which version tracks have you installed on your tank, there are 2 types 1 without rubber pads and 1 with rubber pads, i note on the website it shows the metal sprockets with induction rings to match the rubber track pads.

The other track without rubber pads shows sprockets without the induction rings

I believe the sprockets must match the type of track fitted, as there will be some slight difference, same will go for the others i believe, all though i could be wrong...
Sub.

[OldWolf]

I got an HL challenger 2 last year. It came with metal drive sprockets with anti-slip rings along with all metal track, idler, support arms and road wheels. I replaced the all metal track with DKLMRC metal track with rubber pads. I later replaced those with Tamiya leopard 2 track. I run the tank a good bit out of doors. I have never had it fully de-track in any conditions.
I have had it partially de-track a number of times when it has pulled branches in between a track and its drive sprocket. In most cases, simply reversing slowly clears the branch and puts the track right back on the sprocket.
If you are wondering why I replaced the track twice when I wasn't having de-tracking problems, it was because I found the all metal track too slippery, especially on slopes covered in fallen oak leaves; the DKLMRC track was too grabby, constantly pulling in branches, etc and wedging it in so tight I had to pull the branches out by hand. The Tamiya track has proven to be superior to both.
I have heard that some HL sprockets need washers or O rings added to adjust the sprocket width. That was not a problem with my tank however.
It sounds to me like you have been sent incorrect or faulty sprockets. Might want to send them back.

[Sub]

KH3DP

A couple of simple checks.
1, place the new sprocket on top of the old one, aligne the bottom teeth up, then check all the others they should all line up, if not the new sprockets are the wrong pitch, if they do line up then its more an alignment issue.

2, take a track off lay it out on a flat surface guide horns up, run the complete sprocket in you fingers along the track it should fit perfectly with the track, if it starts lifting out after a few links again wrong pitch if it runs along smoothly the full length its an alignment issue again.
Hope that is useful.
Sub.

[KH3DP]

Thank you for your responses.

This is what happens if I wrap the all metal tracks (no pads) around the metal sprockets that came with the 7.0 Challenger 2 from Toucan Hobby.

This is what happens if I wrap the all metal tracks (no pads) around the metal sprockets with anti-slip rings from I-Love-Porcelain-Flower.

I thought I-Love-Porcelain-Flower was a Toucan Hobby account, so I figured they'd be the right ones. I don't know if it's worth trying to return them to China. So, I guess I'm stuck with them.

[Sub]

Hi,
Thx for the pics,
Yup, those sprockets are totally the wrong pitch, you can even see the difference in distance between the teeth.

If its of any use, i made some induction rings for my challenger 2 using the metal sprockets ( top photo you have) with some large washers filed out to fit the sprocket hub, then held in place with some O rings, worked great for me and still running fine after 4 yrs, i posted a few pics on here with my Challenger, will see if i can find the link. Here you go.

viewtopic.php?f=41&t=25984

Sub.

[KH3DP]

Sub, thank you for the link. I think that's what I'll try next.

[zooma]

If its of any use, i made some induction rings for my challenger 2 using the metal sprockets ( top photo you have) with some large washers filed out to fit the sprocket hub, then held in place with some O rings, worked great for me and still running fine after 4 yrs, i posted a few pics on here with my Challenger, will see if i can find the link. Here you go.

viewtopic.php?f=41&t=25984

Sub.

Hi Sub,

That’s a really good method of making a slip ring.

I have a pair of metal sprockets for my HL Leopard 2A6 that have no slip rings, so I will have a go at replicating your method...... and hopefully your success too !

Do you happen to know the outside diameter of the washers - I am guessing that this dimension is really important.?

Many thanks,

Bob.

[Sub]

Hi Mr Zooma.

The washers i use are 36mm diameter by 2.8mm thick with an internal diameter of 21mm which you have to file or turn out larger to fit the sprocket diameter, i use galvanised washers which can be a little bit harder to enlarge, but won't rust.
Just for info one side of the washer is totally flat the other side has a bevelled edge, i put the bevelled edge towards the guide horns, Don't know if the pics show that, it takes a while to get the internal diameter right, trying them on and off, but they only cost a few pence to buy.
Hope you find this useful.
Regards
Sub.

[zooma]

Brilliant - thanks for the info Sub

Bob.