Heng Long Panzer III detracking issue

[quitcherbitchen]

So I have had two HL Panzer IIIs and of course they suffer from the same issue. Both had metal tracks and idlers/sprockets. My early version from 2015 didnt have adjustable idlers, so I added aftermarket Mato. It would still detrack occasionally. The newer H version from 2023 has the HL version of the track tensioner/plastic. It will detract every time I use the tank on the left side only. My older L version with the Mato adjuster same side. I have carefully looked at all the fittings and fitment and have tried to take out much of the play as I could to ease the situation without any effect on the detracking. The only observation I can see is that the Idler is out of alignment with the rest of the drive train. It has a noticeable angle that looks impossible to remove without modify the arm or the side of the tank. I thought the side flexed but it doesn’t. Any ideas or advice? image widget

[DavidN]

The last wheel before the idler is what guide the track teeth into the idler. If that wheel is loose, your tank will de-track. You need to tighten that wheel almost to the point that its arm becomes unmovable.

[quitcherbitchen]

I'll give that a try

[quitcherbitchen]

Found the problem. Small crack allows the idler to shift left and detrack

[MrChef]

Interesting. I've heard of the Pz III/Stug III having de-tracking issues. I haven't had that pleasure yet for either my Stug or PZ III though. I wonder if I'm just lucky or my install of the Taigen idler adjusters on both made a difference? H'mmm...

[quitcherbitchen]

So I replaced the stock adjusters with the Taigen. Still no joy. I noticed it will detrack immediately no mater the tension on the tracks. Always the same left side will detrack. I tried shimming the idler arm out to make it more inline and even filed the metal idler wheel so that there are no sharp edges where the track guides go in. I looked at the real Stug rear idler that theAustralia armor museum refurbished and noticed it had a very large bevel in the track guide that these heng long metal idler wheels dont have. I didnt want to modify too much so I just cleaned it up with a metal file The whole issue does have a lot to do with rocks getting in between the tracks and the wheels/idler. The fact that the right side will only detrack once in a while Vs the left side which is immediate has me baffled. The wall flex is almost nil. The only thing I can see is that the wheels especially the one closest to the idler that has a shock on it is very loose at the bearing. Mine you these are the stock plastic wheels and swing arms. Also I have read on RC Tank warfare that the shock stiffness is important, but both sides the shock stiffness is the same as I checked. I think I am going to attempt to sleeve the swing arms with brass tubing to get some slop out of the wheels or just buy the metal wheel set. The brass tube is cheap and will give that a try first. I might also limit the swing arm travel for the wheel with the shock.

[quitcherbitchen]

The main issue is rocks. But why only the right side?

[quitcherbitchen]

Ever since the website got hacked I have trouble uploading pictures. Anyone else have this issue?

[SoCalBobS]

I uploaded two to the Steyr thread. They show up on my PC.

[quitcherbitchen]

I noticed other people having the same problem. If you click their attachments it is blank.

[quitcherbitchen]

Here are pictures of rocks. My phone wont work anymore for the website posting pictures. I had to load it on me laptop. anyway The rocks are the reason for throwing the tread, but why mostly only the left side. The right side hardly throw a tread and it is about the same on every clearance and tension level.

[Tang - RC.Senshado]

quitcherbitchen, this may or may not apply for you but I was helping out some people lately with the similar problem. For two tanks I was dealing with, one had a badly angled idler on one side out of the box, another was stripped out of its hole and the idler was hanging on for dear life and the screw's hole had been field repaired once already. Tank #1 would throw its track under a short normal drive and you can hear it crunch a little with the sprocket trying to keep the track in line. Tank #2 was driveable and kept its idler for normal driving. In combat driving it threw its track almost right away.

To show to both owners that the issue was more an alignment issue of the idler and not just that it's secure and the track was tight enough, I manually held the idler parallel to the body and straight and told the owners to run the tank. The tracks stayed on and the idlers rotated perfectly smoth and wasn't exhibiting any behavior that would throw the track easily. To solve his problem I would fill the hole with epoxy for the arm's screw and retap it and make it mount more straight and flush. Since yours is a repaired hull that's my hunch.

Since you know where I work I'd be happy to look at it with you if you're stumped! Couldn't hurt, and we can only make it worse :P

[quitcherbitchen]

Thanks Tang. Mine is more like Tank #2 and will throw a tread while in combat conditions. I have the rear idler almost perfectly alined with the wheels and took a bunch of slop out of the closest wheel by sleeving the inside with metal tubing Only the left side. I devised a way to make the track tensioner auto adjust by putting a spring on both sides of the track adjustment screw. It works remarkably well and I recommend it. The main issue seems the small pebbles get caught up in the idler and stretch the track off the pulley. It almost needs a rock scraper in front of the idler wheel. My Pershing used to detract until John told me to leave half of the rear idler guide out to dump the dirt out. I am wondering if the idler on the metal mato idler wheel if beveled to look more like the real thing could help flush out dirt. In other words, open the gap up to let most of the debri that detracts the tank fall out before it can cause an issue. I am using metal tracks sprockets and idler pulley. The tank only detracks now in loose gravel My taigen Panzer IV never threw a track and it was all metal. Perhaps it is hull flex helping to cause the issue

[quitcherbitchen]

I also added a bearing support similar to what you can buy from germany to the front axle mine is 3 d printed. Also, the website now works for uploading from my phone

[Max-U52]

I don't know if this will help, but one of my favorite tanks is my HL PzIII (tauchpanzer) and it liked to detrack after I added metal sprockets, idlers and tracks, but I noticed that once I put in metal suspension arms and metal roadwheels with rubber tires it hasn't detracked since. I don't know why, but that's what happened for me. Perhaps the metal suspension has less flex so it's harder for the track to come off? Maybe the rubber tires grip the track better than the slippery plastic? It's a mystery to me but I haven't had detracking issues since then. HTH

Gary

[quitcherbitchen]

thanks Max for your first hand experience. i was considering that and may end up buying a set now that you recommend it. I noticed the slop in the plastic wheels is rather large. It probably does have a lot to do with it. Sleeving the plastic wheels with some aluminum tubing I had seemed to help, but I am sure the metal sets are rock solid comparatively. Heng Long seems to have changed the Idler arm length too. This 2023 H model has a much longer and also straight from the factory plastic arm. The Mato metal versions are too short and a different diameter at the pivot seat where it bolts to the hull. Wish I had my old 2015 version to compare it too, but that longer arm must flex as well.

[tank_me]

Thanks Tang. Mine is more like Tank #2 and will throw a tread while in combat conditions. I have the rear idler almost perfectly alined with the wheels and took a bunch of slop out of the closest wheel by sleeving the inside with metal tubing Only the left side. I devised a way to make the track tensioner auto adjust by putting a spring on both sides of the track adjustment screw. It works remarkably well and I recommend it. The main issue seems the small pebbles get caught up in the idler and stretch the track off the pulley. It almost needs a rock scraper in front of the idler wheel. My Pershing used to detract until John told me to leave half of the rear idler guide out to dump the dirt out. I am wondering if the idler on the metal mato idler wheel if beveled to look more like the real thing could help flush out dirt. In other words, open the gap up to let most of the debri that detracts the tank fall out before it can cause an issue. I am using metal tracks sprockets and idler pulley. The tank only detracks now in loose gravel My taigen Panzer IV never threw a track and it was all metal. Perhaps it is hull flex helping to cause the issue

Personally I don't think it's hull flex. I have the same de-tracking issue on my all metal Mato and that hull has zero flex. The Heng Long adjustable idler is horrible as it tilts with any stress on the track. I know I had a lot of interference issues with the metal adjustable idler mount from Mato. I ground some material off of it as the tracks were hitting in certain spots and replaced the fastener as the tensioners would easily come loose in a very short amount of time. I think the last time I tensioned the track, I used some loctite to get it to stay put. Mine is still losing one track.

[MrChef]

One thing I've noticed is that this rear panel that slots in and is glued at the factory isn't true square and may be cockeyed to one side. I removed the panels on both my PzIII and StugIII, centered them, set with pegs and glued the living bejezus out of them with JB weld. I did this while fitting and installing the Taigen idler adjusters. I totally expect both the PzIII and Stug to toss their tracks especially since I run such slack track but during normal judicious driving including outdoors they haven't yet.

[Tang - RC.Senshado]

Thanks Tang. Mine is more like Tank #2 and will throw a tread while in combat conditions. I have the rear idler almost perfectly alined with the wheels and took a bunch of slop out of the closest wheel by sleeving the inside with metal tubing Only the left side. I devised a way to make the track tensioner auto adjust by putting a spring on both sides of the track adjustment screw. It works remarkably well and I recommend it. The main issue seems the small pebbles get caught up in the idler and stretch the track off the pulley. It almost needs a rock scraper in front of the idler wheel. My Pershing used to detract until John told me to leave half of the rear idler guide out to dump the dirt out. I am wondering if the idler on the metal mato idler wheel if beveled to look more like the real thing could help flush out dirt. In other words, open the gap up to let most of the debri that detracts the tank fall out before it can cause an issue. I am using metal tracks sprockets and idler pulley. The tank only detracks now in loose gravel My taigen Panzer IV never threw a track and it was all metal. Perhaps it is hull flex helping to cause the issue

Ah that's all very valid and also likely. I mean if your alignment looks good it's gotta be something else now. Hull flex on some models is pretty bad. Do you want to work with me and make a brace for your tank?

[quitcherbitchen]

What Mr Chef did makes sense. I will check for square. I went to industrial metal supply on another Project and looked around the aluminum scrap bin and was mad at myself for not taking the measurements or parts with me to determine if I should buy it. I like the idea of making a solid aluminum axle to go completely thru the hull and then brace the inside with 1/8 or 3mm sheet That is the German over engineered solution.LOL.