Mobile Material Handler (MOC) Crawler Under Carriage DONE + Video

[doug72]

37 minutes ago, brickless_kiwi said:

I quite like where this moc is going the only thing that jumps out at me is the spacing of your wheels away from the bearing point since they are for transport you can get away with it. 

Thanks - I take your point but not experiencing any bowing of the wheel axles.
I wanted to replicate the double tires as per the machine I am basing my MOC on.

The steered axle support is much closer to the inner tire, the other axle is performing OK without any bow or sag.
I was unable to devise support further out along the axle inside the wheel hub reccess.

Also have re-configured the turntable.

I post some pictures later.

 

Edited February 16, 2018 by Doug72

[doug72]

Non steered axle before:





Additional support added:

Only added to underside to avoid having to take off top deck to modify the same.



Turntable:

Custom turntable modified by removing the two side three wheel supports.

Centre turntable changed from Z56 to Z60 with has less friction, as it now only acts for centring the custom turntable.

The remaining  wheel supports more than adequate for fore & aft forces.

Slewing is by a an 8T gear messing with 13L gear ring internal teeth.

M motor with 8:1 reduction (worm / 8T gear) to give overall reduction of 100:1 for good slewing speed, not too fast & not too slow.

Edited February 16, 2018 by Doug72

[Ox1337]

Hi Doug!

Your creature is very promising. Thank you for sharing.

On your picture I found two unknown for me pieces. In which set you've get them? Roll bearing holder (1) and curved gear rack (2)?

 

[doug72]

1 hour ago, Ox1337 said:

Hi Doug!
On your picture I found two unknown for me pieces. In which set you've get them? Roll bearing holder (1) and curved gear rack (2)?

They are not Lego parts, they are 3D printed and were designed by Efferman and are available from Shapeways.
https://www.shapeways.com/marketplace?type=product&q=efferman

13L studs size in white.
https://www.shapeways.com/product/KGVVXXQ8Z/wheelholder-for-turntable-support?optionId=58698690&li=marketplace

https://www.shapeways.com/product/CBJHXEZWV/turntable-support-13-studs-diameter?optionId=58697999&li=marketplace

Also availabe in a larger siz of 17 studs.

Turntable update:_
Unable to get good location points to lower the 13L turntable support gear ring by 1L  without changing the undercarriage top deck.
Therefore I have lowered side panels to hide the gap..

 

Edited February 17, 2018 by Doug72

[Andy D]

@Doug72 Those turntable parts are outstanding!

Did you have them in mind when you conceived the MOC or did you later find that they fit a need?

Andy D

[doug72]

2 hours ago, Andy D said:

@Doug72 Those turntable parts are outstanding!

Did you have them in mind when you conceived the MOC or did you later find that they fit a need?

Andy D

I brought two sets when Efferman first designed them and have used them in previous MOCs, i.e Level Luffinfg Dock Crane.

That are very useful for MOCs that should use a larger turntable for stable slewing and reduce turning friction.

They are ideal for my current MOC where a Z56 or Z60 turntable would not support the rotating structure very well - the turntable is only used to centre the 3D components.

They are now available in 3 sizes: 11L / 13L / 17L, you can use two sets wheel supports or for heavy loads 4 sets.

The wheels are Lego p/n 42610 LEGO Wheel Hub Ø11.2 x 8 with Centre Groove  and held in place using 2L red axles.

3D parts are in white and I used a grey paint pen to colour them which is a close match with Lego light grey.

Edited February 17, 2018 by Doug72

[Maaboo the Witch]

Wow, love the turntable parts! Makes you wish TLG would do something similar. This is really shaping up.

[doug72]

18 hours ago, Maaboo35 said:

Wow, love the turntable parts! Makes you wish TLG would do something similar. This is really shaping up.

Thanks.

Motors installed:-

Four M motors used as most compact.

M1:- Main boom raise & lower via 3:1 reduction and 24T clutch gear.

M2:- Dipper arm raise & lower.

M3:- Claw or twin bucket actuators
.
M4:  Slewing at 100:1 reduction.
May change M1 to L motor later if need more power required to raise the boom.
Battery box to install behind motors for balance.

The linear actuators for the main boom and the drive up through boom are based on the 8043 Excavator.

Arrangement of body panels still in progress. Elevating cabin to devise.

 

Edited February 18, 2018 by Doug72

[Andy D]

Those XL turntable pieces continue to amaze me! 

How is the support ring attached? I assume there are pin holes on the bottom.

Is there a reason why you did not raise m2 and m3 so as to avoid the use of U-joints? It seems to me that you could raise them 1 stud an remove the 4 U-joints.

looking good!

Andy D

 

[doug72]

1 hour ago, Andy D said:

Those XL turntable pieces continue to amaze me! 

How is the support ring attached? I assume there are pin holes on the bottom.

Is there a reason why you did not raise m2 and m3 so as to avoid the use of U-joints? It seems to me that you could raise them 1 stud an remove the 4 U-joints.

looking good!

Andy D

 

Support ring:-
It's located by 8 pce. 3/4 pins as shown - ( poor lighting now daylight gone & energy saving light bulbs give a weird light when taking photos !)
They only serve to locate the part, the weight above holds it in place and the X56 or Z60 turntable secures it down as well.

They solve a lot of problems when building large MOCs.
The 42009 Mobile crane problems could have done with a better turntable system.

Re Motors:-
I was trying to keep top of machinery housing low but considering raising by 1L remove the U-joints & use direct drive.
The original layout was three M motors side by side which meant couldn't put an L motor in the centre due its bulge shape .
Now that the two upper M motors (M2 & 3) are higher I can put the L motor below on centreline and still keep the the 8T / 24T clutch gear reduction.

Doug

Edited February 18, 2018 by Doug72

[AFOLegofan66]

Very nice so far!! Looking forward to the finished moc!!

[doug72]

35 minutes ago, AFOLegofan66 said:

Very nice so far!! Looking forward to the finished moc!!

Thanks, got a long way to go yet !

I may have to rob parts from previous models to complete this build.

[Maaboo the Witch]

I'm following this closely now.  Can't wait to see the finished article.

[Andy D]

@Doug72 Thanks for the photo. I may get some of those before gears I assemble my 42009 again, I think you are right, this should help.

Your  model is looking great!

BTW: Did you change the motor allignrnt of m2 and m3?

Andy D

 

Edited February 19, 2018 by Andy D

[doug72]

8 hours ago, Andy D said:

@Doug72 Thanks for the photo. I may get some of those before gears I assemble my 42009 again, I think you are right, this should help.

Your  model is looking great!

BTW: Did you change the motor allignrnt of m2 and m3?

Andy D

 

Yes & used an L motor for M1 placed below M2 & M3.

There is 11stud turntable version now which might suit the 42009 crane.

Gear support ring
:-
https://www.shapeways.com/product/WYQND3UBD/turntablesupport-11m?optionId=64700224&li=marketplace

Wheel holders-
https://www.shapeways.com/product/TBN9LW2WJ/wheelholder-for-turntablesupport-11m?optionId=64700240&li=marketplace

Edited February 19, 2018 by Doug72
added links

[doug72]

Revised motor layout:

M2 & M3 raised and M1 placed below them on centreline eliminating the four U-joints.

M1 - L motor - boom actuator drive.

M2 - Dipper arm actuator drive.

M3 - Drive to 4 arm claw grab or clam shell buckets.

Battery box added as counterweight.

Main Boom Actuators module.

Based on the geometry used for the 8043 Excavator.
Some flexing when the two main boom actuators reach full travel both ways despite using a white 24T clutch gear.

Slight forward sag due to boom weight even with using the 13M turntable system.
Framing for base of rotating structure to stiffen.

Doubt a standard Lego turntable would support the weight without a lot of droop ! 

Support structure for the three actuators flexes, so a redesign required and probably move the module back by 1L or 2L.



View of lower main boom,
Showing drive to dipper arm actuator and claw grab.

Boom to be extended by another 15L, and position linear actuator for the dipper arm.

Edited February 20, 2018 by Doug72
Image file text removed.

[BrickbyBrickTechnic]

Awesome WIP so far. I think the diagonal 7l beam toward the front is an illegal technique.

[Maaboo the Witch]

Great stuff! Like the use of the frictionless pins at the actuators - that's gonna be one smooth arm motion!

[doug72]

14 minutes ago, BrickbyBrickTechnic said:

Awesome WIP so far. I think the diagonal 7l beam toward the front is an illegal technique.

I did as well but it fits without any forcing when inserting pins, problem due to the afore mentioned flexing.

Its a process of build evolution !

Anyway I,m going to change that part of the framing to 5L x 9L bent lift arm with 2 x 45 dregs.

Edited February 20, 2018 by Doug72

[doug72]

Illegal beams removed !!
Boom actuator module re-built and now much more rigid & cleaner looking.
Moved module back 2L and braced to the motor cluster..

Now have to figure out where the operators cabin can fit, along with the elevating mechanism.

Edited February 20, 2018 by Doug72

[BrickbyBrickTechnic]

Awesome. Looks a lot cleaner and compact now.

[doug72]

2 hours ago, BrickbyBrickTechnic said:

Awesome. Looks a lot cleaner and compact now.

Thanks for your comments - I tend to build something to determine that the geometry / layout will work in the the space available then refine it until its works and looks better.
Slightly modified the actuator module since last image by repositioning  the end support LEGO Technic Cross Block 1 x 3 (Axle/Pin/Axle) (32184) to give an extra 1L space to fit in the elevating cabin on left side.

[Andy D]

Boom is looking good!

Is your cabin going to be fixed?  Or movable (up-down) Luke your referance material?

This looks like a very interesting and fun design/build.

Andy D

[doug72]

12 hours ago, Andy D said:

Boom is looking good!

Is your cabin going to be fixed?  Or movable (up-down) Luke your referance material?

This looks like a very interesting and fun design/build.

Andy D

Andy thanks,

This is the machine I am basing my MOC on and yes I do intend to have an elevating cabin.

Its an interesting build with lots of problem solving !!





As the build progresses the boom was causing sag of each end of the base of rotating structure.
Now that the side body panels are in place that is now fixed.

Actuator and drive for dipper arm installed on main boom OK.



Dipper arm:-

This has a wide range of movement - almost 180 degs. swing up & down.

The drive to the implement that will go on end of dipper arm is a new problem. 

The normal way using a 20T bevel gear with pin hole & two 12T single bevel gears to put a drive though an articulated joint between the main boom & dipper arm doesn’t work.

It locks up when the dipper arm linear actuator is fully retracted with an angle between dipper arm & main boom of 60 degs.

The two 12T single bevel gears touch and lock. 
U-joints won’t work either due to the acute angle.

I have found a solution with added bonus of a 20/12 reduction in the drive to the implement and now have to build it into the dipper arm.

Angle between dipper arm & main boom now is 30 degs. before gears touch.

Edited February 22, 2018 by Doug72

[Sjoemie himself]

 Looking good Dough and the solutions you come up with are very clever