Problem With WIP MOC, How Do I Fix This?

[StudWorks]

In a previous post I explained how a tan half-gear in this piece was having its axle pulled out of it, while the axle drills through the gear making it unusable. After a first attempt fix, the car drove good without any clicks, but under high torque, the same exact thing happened...
Here's the issue:

When under high torque, the half-gear to the right unnaturally gets pulled out, while the axle chews the inside of the gear. The gears here are part of a DNR shifter alike to the one in the Porsche 911 GT3 RS. One thing I'd like to note is that when shifted to reverse, the problem disappears, meaning that there is a structural problem where the drive gear (bent gear) is.
Here's a picture with the panels removed...

I've tried my best with this and I would really appreciate helpful advice from the experts who have worked through this before.  Thank you.

[Rudivdk]

I would try to somehow make the axles through the tan gears a 5.5 long axle so they touch in the middle. You could even put a half bush on both ends, in between the tan gears. The axle on the black gear should not go through the middle of the two tan gears. This should prevent the tan gears from sliding off.

[Lipko]

Can't you just fix that bracket piece somehow? I'm not sure it's even needed. 

[Techniccrack]

Why not use a differential gear?

Only thing with that you must lock the big gear

Edited November 20, 2019 by Techniccrack

[Appie]

Since others already gave good advice, I did want to add this:

1 hour ago, StudWorks said:

The gears here are part of a DNR shifter alike to the one in the Porsche 911 GT3 RS.

The 42056 set "step 5" flaw this forum (rightfully) went crazy about. Remove the black pinjoiner on the axle of the black bevel gear, this construction does not fit and makes things worse instead of better. It creates alot of friction.

[Didumos69]

2 hours ago, StudWorks said:

 

In this photo you see how much the structure deforms. I would fix that first. Try to incorporate a coherent main structure.



Edited November 20, 2019 by Didumos69

[Thirdwigg]

1 hour ago, Rudivdk said:

I would try to somehow make the axles through the tan gears a 5.5 long axle so they touch in the middle. You could even put a half bush on both ends, in between the tan gears. The axle on the black gear should not go through the middle of the two tan gears. This should prevent the tan gears from sliding off.

That's what I would do.

[Oliver 79]

Maybe get rid of the black bracket and swap the tan bevel gears for the black ones. Didumos69 is right about the structure. More bracing makes a huge difference. 

[StudWorks]

Thanks so much to each of you with your helpful comments!

3 hours ago, Rudivdk said:

I would try to somehow make the axles through the tan gears a 5.5 long axle so they touch in the middle. You could even put a half bush on both ends, in between the tan gears. The axle on the black gear should not go through the middle of the two tan gears. This should prevent the tan gears from sliding off.

@Rudivdk Great idea! I'll try this out and see what happens.

2 hours ago, Didumos69 said:

In this photo you see how much the structure deforms. I would fix that first. Try to incorporate a coherent main structure.

 

@Didumos69 In the picture above, you can see this piece next to the gear to the right of the black bracket. It's a fairly weak connection and I'd thought I'd replace it with something else. A connection with one of these: 

I also forgot to mention that this is only connected by the axles with the tan gears. I guess that could also be the problem.

[StudWorks]

@Didumos69 I am just about to get back on this. Would you agree with my plan above?

[Didumos69]

10 hours ago, StudWorks said:

@Didumos69 I am just about to get back on this. Would you agree with my plan above?

It would improve things for sure. It's good practice to support axles with gears at both ends, but if one of those supports can easily get displaced, that support becomes fairly pointless. So improving the support you mention is a good idea. Whether the rest of the structure is rigid enough remains to be seen.

Edited November 23, 2019 by Didumos69

[Techniccrack]

On 11/20/2019 at 4:20 PM, StudWorks said:

In a previous post I explained how a tan half-gear in this piece was having its axle pulled out of it, while the axle drills through the gear making it unusable. After a first attempt fix, the car drove good without any clicks, but under high torque, the same exact thing happened...
Here's the issue:

When under high torque, the half-gear to the right unnaturally gets pulled out, while the axle chews the inside of the gear. The gears here are part of a DNR shifter alike to the one in the Porsche 911 GT3 RS. One thing I'd like to note is that when shifted to reverse, the problem disappears, meaning that there is a structural problem where the drive gear (bent gear) is.
Here's a picture with the panels removed...

I've tried my best with this and I would really appreciate helpful advice from the experts who have worked through this before.  Thank you.

Why not like this?

 

[Techniccrack]

Sry. That is recommended already:)

[Lipko]

You could also increase the distance between the gears. I see no constrains in the right side of the pictures. If you can accept the big backlash when switching direction, you could even increase the distance by two studs, making space for a 5x7 frame.

I think you could even place a 5x7 frame there.

I also suggest to review the whole frame and consider using this part at few places:

 

Edited November 23, 2019 by Lipko

[JonathanM]

I'd start real simple. You've got space by the looks to make sure that bracket piece is secured properly. Two blue cross-axle pins 2L in it into a lift arm secured on either side.

[Mechbuilds]

Use the shifter extender piece and put it one stud more behind. Then you will have room. 

Edited November 25, 2019 by Mechbuilds

[StudWorks]

@Techniccrack Thank you for your advice. I tried your method and reinforced everything so there is no way that the axle could pop off and drill through the gear and something weird happened.

When the motors move and I stop the wheels, the clicking is still happening because one gear is moving but the other isn't. They're both on the same axle!

I checked the axle and gears but there is no wear on them, so this is really confusing me.

The 2L axle connectors may have some wear to them but not enough to make them unable to use and they're certainly not the reason why one gear on the axle is moving and the other isn't.

@Didumos69 You have been very helpful and I appreciate that. I'm really trying my best here but I am stumped right now. Is there a reason why this happening and any thoughts on how could I fix this? It seems to break the law of physics.

EDIT: I don't think this is the issue. During some tests the black gear and two tan gears in the bracket started skipping, causing a lot of wear to the teeth. I would appreciate it if someone could give me some advice.

Edited November 28, 2019 by StudWorks

[aeh5040]

The 12t bevel gears are just not suitable for high torque, even when braced properly.  It would be better to redesign the assembly.  There are plenty of more robust ways of reversing the direction:

[doug72]

15 hours ago, StudWorks said:

@Techniccrack Thank you for your advice. I tried your method and reinforced everything so there is no way that the axle could pop off and drill through the gear and something weird happened.

When the motors move and I stop the wheels, the clicking is still happening because one gear is moving but the other isn't. They're both on the same axle!

I checked the axle and gears but there is no wear on them, so this is really confusing me.

EDIT: I don't think this is the issue. During some tests the black gear and two tan gears in the bracket started skipping, causing a lot of wear to the teeth. I would appreciate it if someone could give me some advice.

Its obvious the 5-1/2 L axle is too short and only protrudes a 1/4 L inside the black braket, which is not enough to engage with a 12T Tan gear, hence the skipping sound when under power. Probably feels oK when turn by hand & not under load. see photo

AS suggested perhaps best tio start from basics again,

 

Edited November 29, 2019 by Doug72

[Zerobricks]

Why do you even have to reverse the driveline's direction?

[StudWorks]

1 hour ago, Doug72 said:

Its obvious the 5-1/2 L axle is too short and only protrudes a 1/4 L inside the black braket, which is not enough to engage with a 12T Tan gear, hence the skipping sound when under power. Probably feels oK when turn by hand & not under load. see photo

AS suggested perhaps best tio start from basics again,

Thank you. Let me clarify a little better. The 5.5 axle is actually goes halfway in this piece...

The main problem I'm facing with is how to stop the tan gears from skipping and damaging the black gear.

1 hour ago, Zerobricks said:

Why do you even have to reverse the driveline's direction?

The car has a DNR shifter to give the car some authenticity.

3 hours ago, aeh5040 said:

The 12t bevel gears are just not suitable for high torque, even when braced properly.  It would be better to redesign the assembly.  There are plenty of more robust ways of reversing the direction:

Great illustration. I thought about maybe using three 8t gears to reverse the direction without adding additional width would work but I'm worried about the friction.

[aeh5040]

On 11/29/2019 at 7:12 AM, StudWorks said:

Great illustration. I thought about maybe using three 8t gears to reverse the direction without adding additional width would work but I'm worried about the friction.

I try to avoid 8t-8t meshing where possible - it does seem to create a fair bit of friction and stress.  But if space is tight it could be an option.

Edited December 1, 2019 by aeh5040

[doug72]

1/. Does the problem occur without the other parts attached above connecting to the two 16T gears ?

If so the cause is down stream of the broken part.

OR

2/. Does the problem occur when the the other gearbox parts are attached above ?

If so then the problem is up stream of the part that keeps breaking.

++++++++++++++++++++++++++++++++++++++++++++++++

I suspect many forum members have had similar issues building MOCs when we “hit the post”

The answer  is to problem shoot step by step to identify whats causing it and if it not fixable to go back to the & start again.

The problem is not caused by the 12T tan gear,its the result of something causing too much friction or torque either before or after that part.

N.B Dual posts are frowned upon.

Edited December 2, 2019 by Doug72