Alpha Rex 8547 problem with arms motor

[nickneat]

Hi, my son has just got an Nxt 8547 for his birthday and we have built Alpha Rex as per instructions but there seems to be a problem with either the motor or program 4 for Alpha Rex. The motor that turns his upper body (connected to output port A) keeps turning in the same direction instead of one way then the other which is causing the upper body to just break and the cogs to come apart.
Does anyone know of any possible reason for it to do this? We downloaded the software from the cd that came with the set.
My son is getting really upset so any ideas would be greatly appreciated!

[hassenplug]

Double=check to make sure it's assembled correctly. I think motor A SHOULD simply continue in one direction.

It's tricky to build, and align correctly.

Steve

[mrblp]

Hello,

Steve is right, it is not easy to build. Especially the shoulder part is tricky and the wires on top of the brick are in the way for proper turning of the shoulders. The motor is btw only turning in one direction which works correct if built properly.

What I have done is bettering the construction. Use a longer beam at the back of the brick to get the complete shoulder / head / arms part two holes higher than original. Then stabilise the turning part by adding a 5 hole beam to it.

Perhaps you got an idea now what to change to make it work better. If not - sorry, I am bad in explaining things. What do I have to explain to get you understand the improvement? (Great sentence, isn't it? I am not a native english speaker - sorry).

A Happy new year to your family and yourself (and all others of course

Bye marvin

[whatch]

If you have or can download lego digital disgner i have a fix i use it raises the arm one layer and allows more room for the wires under it the other thing to check i the 7 stud backpack retainer is in place in place unfortunatly i can't upload the file
if you are interested reply i can send you the file via email

Bill