Battery Box removal Heng Long Leopard

[FullySemiAutomatic]

If I cut out the battery box in my Heng Long Leopard, is the plastic lower going to flex too much? Are there any other disadvantages?

[keilau]

If I cut out the battery box in my Heng Long Leopard, is the plastic lower going to flex too much? Are there any other disadvantages?

Yes. But you can easily compensate by using braces or bars.

[Rubicon99]

If I cut out the battery box in my Heng Long Leopard, is the plastic lower going to flex too much? Are there any other disadvantages?

No it will not flex enough to be an issue as long as you continue to use the factory screw points to hold the upper and lower hull together. All four of my HL Leopard 2 have the battery boxes removed and I have found no need for any added internal braces.

Now it you are planning to forgo the stock hull mounting method and convert over to magnets to hold the upper and lower hulls together then you many want to consider adding internal bracing. Although a properly set up Leopard 2 lower hull with the correct mix of running components should be able to run reliably with no upper hull attached.

[FullySemiAutomatic]

What kind of braces do you recommend? I am trying to go with a budget option if possible.

[keilau]

What kind of braces do you recommend? I am trying to go with a budget option if possible.

Here are some commercial brace kit for HL RC tank that you can use as examples.

https://www.rctanklegion.com/search?q=hsab

@Rubincon99 conditional assessment of the flex problem is a very good advice. tank_me likes to remove the battery box and re-enforce the tank Chassis. He had posted some examples on this forum. You can PM him for more help.

[Meter Rat]

A simple square frame, made from 25mm x 25mm aluminium angle. I bonded mine along the length of the chassis, and bolted in the cross pieces with 6mm counter sunk nuts and bolts. I’ll photograph it later. Took me about an hours work.

[keilau]

A simple square frame, made from 25mm x 25mm aluminium angle. I bonded mine along the length of the chassis, and bolted in the cross pieces with 6mm counter sunk nuts and bolts. I’ll photograph it later. Took me about an hours work.

Cannot wait for your picture. I can visualize what you did and believe you have a wonderful approach to the chassis flex problem.

The HL Leopard 2A6 has a strong chassis and I will be keeping the battery box. My concern is the TongDe US M60 Patton which has a flimsier chassis. I have been thinking about how to strengthen it.

[Meter Rat]

Cannot wait for your picture. I can visualize what you did and believe you have a wonderful approach to the chassis flex problem.

The HL Leopard 2A6 has a strong chassis and I will be keeping the battery box. My concern is the TongDe US M60 Patton which has a flimsier chassis. I have been thinking about how to strengthen it.

Home from work and a couple of beers, for Burns Night. But as I said I would assist with photos.

The rear brace has the speaker sitting on it so isn’t the most clear, and the cutout in the second picture are for the idler mounts. All boned in with JB Weld and bolts so the front and rear braces are removable.All in cost about £5 as it was made from scrap from work. That is only because we had run out of countersunk bolts so had to buy my own. 😭

[Rubicon99]

Cannot wait for your picture. I can visualize what you did and believe you have a wonderful approach to the chassis flex problem.

The HL Leopard 2A6 has a strong chassis and I will be keeping the battery box. My concern is the TongDe US M60 Patton which has a flimsier chassis. I have been thinking about how to strengthen it.

The TD M60 ABSOLUTELY DOES NOT need hull braces even with magnet hull closers (assuming they are installed with quality magnets and mounted correctly). Why because the lower hull has torsion bars and the suspension arms are held in place with two supporting bearings on top of this the outer hull also has bolted on full length blisters that add additional support to the hull. The combination of these parts make the lower hull rather forgiving. Anyone that says different has very little experience with running the TD M60 in challenging terrain. All you would be doing is waisting time and effort to produce no better run results. But it is your time so who am I to say how you should spend it.

I can run my TD M60s all day over rough terrain with the upper hull completely unsecured and never suffered any de-tracking issues. Sure the upper hull will bounce off here and there, but that has nothing to do with flexing, it has to do with abrupt jarring forces from the rough terrain.

The real problem with the TD M60s is the poor upper to lower hull fitment. If braces could fix this I would say they would then be worth it to install. Even mix and matching upper to lower hulls from the four M60s I have, not one combination has been found with fit quality nearing even the most basic HL tank.

[FullySemiAutomatic]

I like the premade braces, but I am thinking if I make my own out of aluminum it will be less expensive. I wonder if Home Depot or Lowes has aluminum bars like that.

[Meter Rat]

This is proving a good discussion, and I’m sure Keilau will have his own thoughts and opinions. I have no experience or interest with a TD M60 so my experience is only with my Challenger, which means I cannot contend with Rubicon99 regarding these models. I am at the bottom of the pile with regards the knowledge on here. I know I will install a brace in both my T72 and Abrams. The T72 is not too bad when running. The Abrams is awful. I think this is due to the length of the chassis and the tensioners being pulled out of alignment on modern tanks that require the tracks to be tight. So causing them to de-track. I will be bracing both of these, regardless of whether I install magnets, just to stop the front to back flex, as it has transformed the Challenger.

[Meter Rat]

I like the premade braces, but I am thinking if I make my own out of aluminum it will be less expensive. I wonder if Home Depot or Lowes has aluminum bars like that.

No use to you. I think B & Q in the UK is is the same as Home Depot. I did mine with a junior hacksaw, file, engineering square, and a hand drill and bits.

[keilau]

I like the premade braces, but I am thinking if I make my own out of aluminum it will be less expensive. I wonder if Home Depot or Lowes has aluminum bars like that.

Menards is my favorite hardware store in the Chicago area. I will pick 1/16x3/4 aluminum angle. I will buy a longer piece and save some for spare. I am sure you can find similiar items at Lowes or Home Depot too.

https://www.menards.com/main/hardware/sheet-metal-rods/hillman-reg-solid-aluminum-angles/11349/p-1444432405248-c-9215.htm

Meter Rat , thank you for the idea.

[Rubicon99]

This is proving a good discussion, and I’m sure Keilau will have his own thoughts and opinions. I have no experience or interest with a TD M60 so my experience is only with my Challenger, which means I cannot contend with Rubicon99 regarding these models. I am at the bottom of the pile with regards the knowledge on here. I know I will install a brace in both my T72 and Abrams. The T72 is not too bad when running. The Abrams is awful. I think this is due to the length of the chassis and the tensioners being pulled out of alignment on modern tanks that require the tracks to be tight. So causing them to de-track. I will be bracing both of these, regardless of whether I install magnets, just to stop the front to back flex, as it has transformed the Challenger.

The issues with "de tracking" on the T72/90 are not flex related. The issue is do to a misaligned of the sprockets. The sprockets (typically the right one being the worst) sit inboard ~2mm further then they should. This causes the tracks to ride off the sprockets in hard turns or when debris is pulled up into them.

To solve the issue simply add a "spacer" to the inside of the sprockets. This will aline them with the tracks and greatly increase track retention. Also running drive shaft hull bearing supports and aftermarket dual pin tracks goes a long way to helping with retention.

The other issues and a much bigger concern is the forward hull sides at the forward lower hull glance cracking and ripping the sides of the hull away(all five of my T72/90s had this issue develop). This is the area that needs "re enforcement" but unfortunately internal braces unless attached through the forward hull will have no effect in stopping the cracks/rips.

The Abrams is one that people have tried and tried over many many years to make run well to various degrees of success. Until the newest Abrams 6.0+ version. They are not the same animals as the old 5.3 and in such are super easy to make run reliably. The problem is people are still using the techniques from the older Abrams which are not needed (such as bracing). What is needed is simply adding the drive axle hull support bearings and Tamiya Abrams or Tamiya Leopard 2 tracks(both work perfectly on the HL Abrams sprockets). Why Tamiya tracks? Couple of reasons, one their guide teeth are slightly taller then any other track available and this greatly aids in retention on the sprocket and road wheel especially in tight turns on high friction surfaces where the wheels have a tendency to "ride off" the tracks. Second they are dual pin and extremely lightweight yet super strong. Their light weight reduces the stress on the hull which heavier aftermarket market tracks tend to produce.

Combine the new 6.0+ stock adjustable idler, drive axle hull bearings and Tamiya tracks and you have a HL Abrams now on par with a $1200 Tamiya Abrams in reliability. I have multiple Abrams including Tamiya Abrams and using the formula above the new 6.0+ HL Abrams are easily a one to one match for running reliably against my Tamiya Abrams and not one of the HLs has hull braces.

Hull braces with the new generation of HL tanks is just not returning the bang for the buck it once did with the old 5.2/5.3 generation. Does it hurt anything to install it, no not at all, it's just not needed as much anymore with the improvement in HL product quality. If it makes a person feel good and want it in their tanks by all means install it.

Note: I am responding so all the others reading this thread do not start to think hull bracing is a necessary addition, because it simply is not. It is a last ditch effort after everything else has been tried. I am attempting offering proven ideas to try first.

[tank_me]

I braced the inside of my TondDE M60 as the sides were actually slightly bowed inward in the rear. It was bowed enough that I could readily see it. I didn't do it for track retention purposes and I braced the inside of the motors as one of my motor screws was stripped. I'm just trying to take some of the stress off the remaining screws and avoid any issues with the gearbox mounts. Everyone has their own opinions and or experience with what works. The braces cost me nothing as the material was left over 3D printing mistakes.

[Rubicon99]

I braced the inside of my TondDE M60 as the sides were actually slightly bowed inward in the rear. It was bowed enough that I could readily see it. I didn't do it for track retention purposes and I braced the inside of the motors as one of my motor screws was stripped. I'm just trying to take some of the stress off the remaining screws and avoid any issues with the gearbox mounts. Everyone has their own opinions and or experience with what works. The braces cost me nothing as the material was left over 3D printing mistakes.

Yours is a good example of the exception I wrote about in an earlier post (#9 last paragraph) when bracing is needed and for a good reasons which goes beyond trying to keep the tracks on.

[Meter Rat]

Rubicon. Thank you for the information and advice. Now I’m going to sound terribly, terribly rude and unappreciative. I have read a lot of your advice and absorbed it. I try to take the best proven advice for all places, and implement them to the best of my abilities. Tamiya tracks are difficult to obtain here in the UK for a sensible price. Meaning i have to look at alternative solutions first. I am also aware of the cracks which appear in the hull of the T72. I will address this.I was not aware of need ing to fit spacers on the sprockets.

l am not in a position to throw money at a solution. I do however have access to some free materials , and a certain about of time at work, which allows me to develop things. I like to build and investigate problems one step at a time, and because I enjoy it. I do look for a cheep free fix, before investing in expensive parts. Making a hull brace is, for me a cheep and accessible thing to do. Because I have the facilities I will do it and see what happens. Yes I will go about thing arse and face sometime. I will look at implementing spaces for the T72 though, first If a DIY solution helps someone then that is a good thing.
Thank you for your input and knowledge. Would certainly be stuck without it.

[Rubicon99]

Rubicon. Thank you for the information and advice. Now I’m going to sound terribly, terribly rude and unappreciative. I have read a lot of your advice and absorbed it. I try to take the best proven advice for all places, and implement them to the best of my abilities. Tamiya tracks are difficult to obtain here in the UK for a sensible price. Meaning i have to look at alternative solutions first. I am also aware of the cracks which appear in the hull of the T72. I will address this.I was not aware of need ing to fit spacers on the sprockets.

l am not in a position to throw money at a solution. I do however have access to some free materials , and a certain about of time at work, which allows me to develop things. I like to build and investigate problems one step at a time, and because I enjoy it. I do look for a cheep free fix, before investing in expensive parts. Making a hull brace is, for me a cheep and accessible thing to do. Because I have the facilities I will do it and see what happens. Yes I will go about thing arse and face sometime. I will look at implementing spaces for the T72 though, first If a DIY solution helps someone then that is a good thing.
Thank you for your input and knowledge. Would certainly be stuck without it.

I don't consider your post rude at all. You have to work with what you got on hand. Been there myself and gained knowledge the hard way. Sometimes with success like the cheap and easy sprockets spacer "fix" other times having to through money at a problem.

[Kendusan28]

The issues with "de tracking" on the T72/90 are not flex related. The issue is do to a misaligned of the sprockets. The sprockets (typically the right one being the worst) sit inboard ~2mm further then they should. This causes the tracks to ride off the sprockets in hard turns or when debris is pulled up into them.

To solve the issue simply add a "spacer" to the inside of the sprockets. This will aline them with the tracks and greatly increase track retention. Also running drive shaft hull bearing supports and aftermarket dual pin tracks goes a long way to helping with retention.

The other issues and a much bigger concern is the forward hull sides at the forward lower hull glance cracking and ripping the sides of the hull away(all five of my T72/90s had this issue develop). This is the area that needs "re enforcement" but unfortunately internal braces unless attached through the forward hull will have no effect in stopping the cracks/rips.

The Abrams is one that people have tried and tried over many many years to make run well to various degrees of success. Until the newest Abrams 6.0+ version. They are not the same animals as the old 5.3 and in such are super easy to make run reliably. The problem is people are still using the techniques from the older Abrams which are not needed (such as bracing). What is needed is simply adding the drive axle hull support bearings and Tamiya Abrams or Tamiya Leopard 2 tracks(both work perfectly on the HL Abrams sprockets). Why Tamiya tracks? Couple of reasons, one their guide teeth are slightly taller then any other track available and this greatly aids in retention on the sprocket and road wheel especially in tight turns on high friction surfaces where the wheels have a tendency to "ride off" the tracks. Second they are dual pin and extremely lightweight yet super strong. Their light weight reduces the stress on the hull which heavier aftermarket market tracks tend to produce.

Combine the new 6.0+ stock adjustable idler, drive axle hull bearings and Tamiya tracks and you have a HL Abrams now on par with a $1200 Tamiya Abrams in reliability. I have multiple Abrams including Tamiya Abrams and using the formula above the new 6.0+ HL Abrams are easily a one to one match for running reliably against my Tamiya Abrams and not one of the HLs has hull braces.

Hull braces with the new generation of HL tanks is just not returning the bang for the buck it once did with the old 5.2/5.3 generation. Does it hurt anything to install it, no not at all, it's just not needed as much anymore with the improvement in HL product quality. If it makes a person feel good and want it in their tanks by all means install it.

Note: I am responding so all the others reading this thread do not start to think hull bracing is a necessary addition, because it simply is not. It is a last ditch effort after everything else has been tried. I am attempting offering proven ideas to try first.

Hey Rubicon!
I would like to ask what type of spacer you should add to the T90/T72? As for me I used a ruler and my gearboxes are in line, and the right one isn't shifted.
Thanks in advance,
Kendusan28

[Rubicon99]

Hey Rubicon!
I would like to ask what type of spacer you should add to the T90/T72? As for me I used a ruler and my gearboxes are in line, and the right one isn't shifted.
Thanks in advance,
Kendusan28

It's not that the gearboxes, it's the mounts they are on. The mounts are inboard slightly, thus throwing the gearbox placement and corresponding shaft lengths off just enough to cause some "minor" issues(When measured everything looks correct I know I did that too).

When HL released the new 6.0+ T72 they simply reused the old T90 hull and added idler adjustments. They did not correct the mounts because to them it was not a "issue" and the tank ran satisfactory for their "toy first" standard.

Why does one side have more of an issue then the other? I suspect it is simply because of the offset road wheel arrangement that tanks like the T72/90 have. One side is simply more forgiving then the other. But then I might be wrong about that. Before I found the spacer fix I tried internal braces, drive axle support bearing, three different brands of aftermarket gearboxes and nothing worked as well as simply adding the spacer.

Today on my newer T72s I simple run the spacer and hull bearing to deal with the de tracking issue. There are older videos on my Instagram @ fsttanks of my T72s running off road and being beat up doing stupid stuff. All these are just simply with sprocket spacers.

Ok what do I use as a spacer. I use small thin rubber "O" rings with a small section cut off to from the "D" shape of the internals hub of the sprockets. These are inserted into the sprockets and then attached the sprockets as normal. Now tracks do still come off in extreme cases where the sprockets are packed with dirt, sand, mud and other debris but that is to be expected with any RC tank.

On another note the issue pointed out here are not just with the T72/90 they are also with the Challenger. It too has a few easy fixes but that is for another thread.