Dump Truck question

[Rishab N]

Well I worked a bit and got a linkage that was able to lift 2 unimog wheels which is a large improvement

The angle could be less but i'll get to that later

Feel free to make suggestions on how it could support more weight as I still have a long way to go till lifting the bed plus cargo. Also have i used an illegal building technique with the grey axle connectors which attach to the yellow lift arms and the bed?

Thanks

Rishab

[Appie]

Well I wouldn't call it "illegal", but it also isn't very sturdy. It's fine on things that are only on a model for looks imo, but this is attached to the bucket, it might let go. Maybe try to work with another part to off-set the required half stud? Technic cams come to mind. Would need to make room with the 2x4 liftarms that are connected to the chassis, but you can work something out probably.

[Rishab N]

Well I wouldn't call it "illegal", but it also isn't very sturdy. It's fine on things that are only on a model for looks imo, but this is attached to the bucket, it might let go. Maybe try to work with another part to off-set the required half stud? Technic cams come to mind. Would need to make room with the 2x4 liftarms that are connected to the chassis, but you can work something out probably.

They've stayed pretty sturdy for the time being. Unfortunatley i dont have any cams and i just finished ordering all the parts Any other solutions?

[Cumulonimbus]

Apart from the fact that it might not be the most sturdy solution, it looks to me that the movement of your mechanism is not fully defined. It is a bit tricky to explain, but by adding an extra pivot between the grey and the yellow part of your linage you have introduced an extra degree of freedom. This means that the linkage can still move independent of the LA. A proper linkage should feel rigid in all its positions and should only be moved by the LA.

I think that if you rebuild the yellow part so that it attaches at the same pivot point the grey part is now attached to your tilting bed, you should have a functional mechanism. Good luck!

Edit: I made a quick copy of your chassis with the linkage I propose. I couldn't work out the position of your LA from the photo's, so I guesstimated.

Open position:

And closed:

Edited July 20, 2014 by Cumulonimbus

[Rishab N]

Thanks! However there's still the problem of the half stud offset so I don't think I'll be able to attach it like that. I'll try a similar solution and see how it goes. Also are there any other pieces which are able to offset things by a half stud?

[Zerobricks]

Thanks! However there's still the problem of the half stud offset so I don't think I'll be able to attach it like that. I'll try a similar solution and see how it goes. Also are there any other pieces which are able to offset things by a half stud?

You can always use a L shaped beam to get some offset.

Edited July 21, 2014 by Zblj

[Rishab N]

Well I used Zblj's solution and used L shaped beams. The linkage can now lift a lot more. In fact it lifts the bed and 3 unimog tires with ease. However everytime I lift it, There is always a crunching sound in the beginning, but when slightly pushed up it disappears after reaching a certain angle. At first I thought it was the weight of the dump bed, yet it still crunched a bit without it. It also crunched with the extra weight added which leads me to believe that the linkage is colliding with a certain piece in the chassis and when slightly lifted it is able to go over that piece. However, I was not able to locate the source of the problem

Here are some pics

Some close ups

As always suggestions for improvement ,such as a linkage for even more weight and a solution to the problem, are always welcome

Thanks

Rishab

[Zerobricks]

The crounching sound can come from friction pins you used Glad my linkage works!

[Balrog]

Common advice: Don't use friction pins on moving parts like this.

[Rishab N]

The crounching sound can come from friction pins you used Glad my linkage works!

Common advice: Don't use friction pins on moving parts like this.

Oh now I feel stupid Thanks I'll try that soon

[gti180]

this truck would be so cool if you could go a step further and turn that dump bed into a skip loader

[Rishab N]

this truck would be so cool if you could go a step further and turn that dump bed into a skip loader

Oh that would be great I'll see what I can do after I finish the dump truck

[Balrog]

Is it again based on your 5 axle 8258?

[hrontos]

That crunching sound can be also the clutch integrated into LA. You may be need to change a starting angle a bit by changing the linkage or LA position.

[Rishab N]

That crunching sound can be also the clutch integrated into LA. You may be need to change a starting angle a bit by changing the linkage or LA position.

I think I have the pre 8043 acuators so no clutch. I'll try changing the angle as the area the LA is attached to is bending the axles

Is it again based on your 5 axle 8258?

Yep the only thing still left of the 8258 is the front area and steering the rest is all MOC

Also I changed it all to non friction pins but no luck

[Blakbird]

I think I have the pre 8043 acuators so no clutch.

???? The linear actuators have always had an internal clutch. 8043 didn't change that. The change that happened during 8043 was just some internal tolerances.

[Rishab N]

???? The linear actuators have always had an internal clutch. 8043 didn't change that. The change that happened during 8043 was just some internal tolerances.

I always thought the recall was due to some clutches Guess not

[Balrog]

Rishab I just found this on Brickshelf:

Perhaps it helps you. Here is the link to the folder: Click

[Rishab N]

Thanks Balrog! I need to take a good look at that . Currently I have taken the entire rear of the truck apart for a couple reasons. I decided that placing the XL motor closer to the front would allow me more room for the acuator and linkage mechanism. Also my earlier design was affecting the stability of the chassis and there was a lot of flex so I'm working on makingit much stronger

[bultech]

What about this:

[Rishab N]

What about this:

Thanks, however I'll have to do another chassis redesign inorder to get that and I'm really frustrated with this project (impatience)

So, after a lot of frustration and trying so many linkages I gave up and decided to use a linkage based off Zblj's dump truck . Its extremely powerful, however it isnt able to lift anything that's placed further away from the connection point of the actuator. Should i move the connection point to change this or is there another solution. Here are some pics

Edited August 5, 2014 by Rishab N

[hrontos]

You do not need such high tipping angle, so try shorter beams. You will get smaller tipping angle, but more force.

[Rishab N]

You do not need such high tipping angle, so try shorter beams. You will get smaller tipping angle, but more force.

Thanks that's what I was thinking too

Edited August 5, 2014 by Rishab N

[Balrog]

I'm gonna lend myself this linkage. The tipping angle could be just enough for what I am trying to build

[Rishab N]

I'm gonna lend myself this linkage. The tipping angle could be just enough for what I am trying to build

Great! Guess we both have to thank Zblj for this great solution