DNR Shifter Issue

[StudWorks]

2 hours ago, Gray Gear said:

Why do people use panels for framework? Imo they are inferior to frames. Like in this case, you have a 7 studs wide center tunnel, so why lose out on the best mounting option, and use panels insted? I dont get it.

That makes sense, but I don’t know how I could replace the black panels with frames, without changing the rigidity. I am willing to do so. Any tips with that would be appreciated.

9 hours ago, Zerobricks said:

From my experiences the orange wave selectors are not really suitable for high torque gearboxes.

Hence why I needed that second 90 degree limiter.

[suffocation]

You can replace the 5x11 panels with LBG 5x11 frames. They should be sturdier and offer more - and better - attachment points.

As for the limiter, have you tried using Sariel's stepper? It should be able to handle quite a bit of torque.

 

Edited December 13, 2019 by suffocation

[StudWorks]

16 hours ago, suffocation said:

You can replace the 5x11 panels with LBG 5x11 frames. They should be sturdier and offer more - and better - attachment points.

As for the limiter, have you tried using Sariel's stepper? It should be able to handle quite a bit of torque.

I could replace them with 5x11 frames, but then I have to find a better way to mount it to the side beams.

If I end up replacing the panel with the frame, I'd still not know how to fix the reinforcement issues that bends the DNR gearbox.

I'd also have to mount the frame in a different area, since there are less pin holes in the frame than the panel.

I am willing to mount the frames but I am not sure as to how to reinforce the gearbox into the frame to stop the bending. Thank you.

[Gray Gear]

Use the normal 5x7 Frames, not the H shaped ones. First measure to stop bending is to have overlapping liftarms left, right and above the frames mointed in the center. That will reduce bending by a lot, but it'll take more for a sturdy chassis.

[StudWorks]

On 12/13/2019 at 4:02 PM, Gray Gear said:

Use the normal 5x7 Frames, not the H shaped ones. First measure to stop bending is to have overlapping liftarms left, right and above the frames mointed in the center. That will reduce bending by a lot, but it'll take more for a sturdy chassis.

@Gray Gear Thanks for the advice. You mentioned having overlapping liftarms left, right and above the frames mounted in the center. I am not sure how to do that, my issue is that I can't find a solution to mounting the frames to the beams on the side, as mentioned in my previous comment.

And the main problem I am facing with is this...

This is the shell of my gearbox that holds all the gears.

And this is what happens when it goes under torque. In the picture above, you can see that the axle is bent. Do you have an example of how I can fix the bending and mounting issues? Thank you.

 

[doug72]

Edited December 15, 2019 by Doug72

[tomek9210]

Don't use 3L beams. Use longer beams instead and attach them to the chassis.

[Maaboo the Witch]

I'm not much for MOCing, but I know panels should be used near-exclusively for outer bodywork. Beams are best for structural purposes as they are more rigid.

[StudWorks]

Thanks. Before I do anything else I need a better way to replace this panel...

I'd use frames instead of panels as suggested but they won't fit because the of the gears. Any ideas for something else to replace the black panel here?

If I had a LDD example, this would be much easier.

Edited December 15, 2019 by StudWorks

[Gray Gear]

Instead of asking how to do the most basic  things work you should be trying things yourself like almost everyone else here. I dont want to offend you, we all start somewhere, but the way you built that that shifter housing makes you seem really inexperienced.

[doug72]

We have all "Hit the wall" when building MOCs & have to re-think & start again.
You learn from mistakes. Sometimes it means giving up for a while and then re-look again to find another way of getting what you desire.

[suffocation]

It's really hard to help without knowing more about the bigger picture. Anyway, as Didumos69 already pointed out (maybe in the other thread - can't remember) you should have a solid, light-weight central column running the length of the car to ensure maximum rigidity. It'll also give you plenty of mounting points and minimise gear skipping/axle bending. Something like this should do the job (thrown together just to give you a basic idea and with plenty of room for improvement):

Other than that, you really need to go through a lot of trial and error to learn how to build effectively and efficiently and figure out what works for your own models.

 

Edited December 16, 2019 by suffocation

[doug72]

It’s hard to determine what you are trying to build without an overall image showing what it is !

Photos say a thousand words.

Edited December 16, 2019 by Doug72

[StudWorks]

Thank you everyone for the advice. You're right, I'm a beginner at MOCs and Eurobricks has been a very valuable resource for help me to learn from the best. I read all posts to learn as much as I can, but I just started doing so a few months ago. I do trial and error the best that I can and I have to learn to be more patient when I "hit the wall" too.

@suffocation I really appreciate the pictures that you have provided and especially your insight. Your illustrations are examples of frames that would definitely work, but unfortunately there is a 5 stud wide limit in the black center tunnel (anything wider would affect the interior) and I need to have the driving ring to be just off center as per the car that I am building and the input axle needs to instead be in the middle. Your example is very close and I appreciate that, but not exactly going to fit this build. I am in the process of taking your advice and doing much more trial and error with options that may work. I will keep plugging along.

As requested, here are some pictures that will show everything, you can see the input axle in middle and driving ring off center, and how I need it to be as compact as possible. Also, I am attempting to replace the panels but can't find anything that wouldn't bump into the gears just yet. I will keep trying.

[StudWorks]

@suffocation Today I built a modified version of your suggested framed design gearbox as a prototype to what could someday fit into my MOC.

In the pictures below, you can see that I moved the H beams from one side into a different area to make more room that is required to fit inside my car. I don't know if this is the best method to decrease the width or not. It would be ideal to use your design somehow, but with the width a stud or two less.

The only issue (that I had as well with my previous DNR shifter) was with the gear skipping in the spot where the yellow axle is pointing at, the blue gear to the gray gear (on this side where I point at, not the other). I would be really excited to use this design if I only I can solve the gear skipping and get everything to the required width.

Edited December 18, 2019 by StudWorks
Better Pictures Provided With White Background

[sirslayer]

did you aligned the 5 x 11 framed element??  There are grooves in the 5x11 element and the top frame 5x11 grooves should be pointing down and the bottom 5x11 grooves should be pointing up!!  here is an example of the grooves

 update nevermind .. that is not the case !!sirslayer lego technic by Victor Mendoza Jr, on Flickr

 

Edited December 18, 2019 by sirslayer

[doug72]

Could take photos against a white background, makes it easier tro see the parts.

 

Looks as if the 16T gear teeth are not fully engaged with the blue 20T DBG teeth.

Are the gears in your set up at these centres as images below ?

Edited December 18, 2019 by Doug72

[doug72]

Using your photos I have built your gearbox which only seems to be for reversing direction of drive.

Unable to replicate the slipping of any of the gears
So problem must lie somewhere else, check the internal clutch teeth on the blue 20T DBG's and on the grey driving bush.

What 3L bush are using with the drive ring ?
3L with ribs or 3L without 

There are much easier and simpler was of drive using double bevel gears throughout without the need to offset 16T gears to get proper meshing.

I would recommend you getting a copy of:- The Unofficial Lego Technic Builders Guide  by Sariel.

Has lots of solutions for gearing, gearboxes, Technic etc.

 

 

Edited December 18, 2019 by Doug72

[StudWorks]

2 hours ago, Doug72 said:

Using your photos I have built your gearbox which only seems to be for reversing direction of drive.

Unable to replicate the slipping of any of the gears
So problem must lie somewhere else, check the internal clutch teeth on the blue 20T DBG's and on the grey driving bush.

What 3L bush are using with the drive ring ?
3L with ribs or 3L without 

There are much easier and simpler was of drive using double bevel gears throughout without the need to offset 16T gears to get proper meshing.

I would recommend you getting a copy of:- The Unofficial Lego Technic Builders Guide  by Sariel.

Has lots of solutions for gearing, gearboxes, Technic etc.

@Doug72 Thank you. In fact, I do own Sariel's guide and it has been very helpful. I updated the photos with a white background as per your request, thanks for the advice.

The way I replicate the gear skipping is by placing a piece on the output axle that will make it unmovable and crank the input axle until the skipping occurs.

The 3L piece I am using with the drive ring is this:

I am 100% sure that the skipping is from the two gears I mentioned. In my example, during the skipping, the input axle moves and the output does not. I'm really puzzled with this and want to know what I can do to fix the skipping between the blue and gray gear. I'll build your example of my gearbox and see if the same thing happens on my end. Once again, I really appreciate your advice and illustrations.

[Technonsense]

The slipping can be because the H-frame moves out of the pins:

[StudWorks]

11 minutes ago, Technonsense said:

The slipping can be because the H-frame moves out of the pins:

Thanks I checked that out. Could, but when I test for skipping the H-frames seem to be still.

I'm 100% sure it's because of the gears. Under high torque, the blue gear and gray gear lose a lot of contact with each other enough to cause the skipping.

[Gray Gear]

What the hell? Are you applying that much force that the axles bend? Keep in mind, this is not going to be the weakest link in your system (thats going to be the diff or the pieces connecting to the wheelhubs), so there is no need to make this able to withstand a whole lot more than these will be able to handle.

[StudWorks]

1 hour ago, Gray Gear said:

What the hell? Are you applying that much force that the axles bend? Keep in mind, this is not going to be the weakest link in your system (thats going to be the diff or the pieces connecting to the wheelhubs), so there is no need to make this able to withstand a whole lot more than these will be able to handle.

Yeah, you’re right. I was overdoing everything because I didn’t want the skipping to occur when the car drives. I’m just trying to make the chassis have the tightest gear setting possible. You made me rethink that the hardcore testing was overdoing it, thanks.

[Technonsense]

Try this:

It can easily handle the torque of a XL-motor and will fit nicely into your chassis

Good luck with your car! I

[StudWorks]

4 minutes ago, Technonsense said:

Try this:

It can easily handle the torque of a XL-motor and will fit nicely into your chassis

Good luck with your car! I

@Technonsense Thanks for the example! If I could make the left side a stud less width, put in the new driving rings, and if it doesn’t have gear skipping, it will be great.