Duaner

Lego Technic 42070 Tow Truck - outriggers issue?

Recommended Posts

Hello,

I just finished assembling the set.  However, when lowering / raising the outriggers, I notice that they are not deploying at the same speed.  The rear one moving faster than the lateral ones.  Consequently, it reaches its low and high positions quicker and stops while the two others are still moving.  I can then hear a distinctive "clicking sound" of the rear gear set since the axis is still rotating to fully deploy the lateral pieces. It does sound that it is forcing on the gear teeth and make them "skip".

Is this normal?  If not, any clue on possible assembly mistake or workaround?

Thank  you for the feedback! 

35143850863_1f12ea341c_c.jpg

Share this post


Link to post
Share on other sites

It might be a gearing issue, you can check the gear arrangement on all outriggers and make sure all of them have the same gear ratios, basing in the description of the problem, the difference of the gear ratios between the outriggers would cause some of them to complete all their movement before the others, resulting in that "skiping" noice.

Share this post


Link to post
Share on other sites
23 minutes ago, Imanol BB said:

It might be a gearing issue, you can check the gear arrangement on all outriggers and make sure all of them have the same gear ratios, basing in the description of the problem, the difference of the gear ratios between the outriggers would cause some of them to complete all their movement before the others, resulting in that "skiping" noice.

It´s not a gearing issue. I don´t own the set and probably never will, but from experience I would bet the clicking sound comes from the mini linear actuators. They are the much weaker parts under stress compared to gears. Although it´s not a big issue concerning damaging, it´s annoying. I´ve looked into the building instructions and it´s obvious that the outriggers are mounted different ways and operate at different angles. One LA has longer travel than the other. Poor design, but most kids don´t care because everything is huge and so impressive *oh2* !

Edited by brunojj1

Share this post


Link to post
Share on other sites

It happens for me and apparently for the set in Sariel's review as well. So it's a universal problem. However I managed to find a simple MOD to fix this. Will post into 42070 MOD thread later.

Share this post


Link to post
Share on other sites

I think that a good modification to solve this problem would be to add differentials to the outriggers drive train, so even when an outrigger has reached its maximum length, it wont start to skip until all the remaining outriggers reach their maximum length too, i will see if i can get the LDD file for the model and test this modification.

Share this post


Link to post
Share on other sites

Thank you for all the quick replies.  I had a closer look at the linear actuators and they are indeed attached to the outriggers with two different angles (rear more open than lateral) explaining the quicker speed of the rear assembly.  As already commented, all gears well appear to have the same ratio.  I will try the suggested mod, easy enough for a newcomer like myself!

12 hours ago, Ngoc Nguyen said:

Thank you, I will try this.

Edited by Duaner

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.