AR45p SCX10 iii rear axle assembly issue

[halllon]

I’m putting together an AR45p axle and there seems to be some kind of mismatch between the top portal gear, axle shafts and bearings. The top portal gear sits too far out. It looks like I’m using the correct 5x11x4 bearings and correct parts.

What’s wrong here?

[nielsm]

Be aware of the appearance of a space for another bearing on the axle. The directions are correct, but it can look like you'd want to put a bearing there. You should not put a bearing in that side as it could create spacing issues like you describe.

Another issue is the gears have what look like pin slots on both sides. One is a round pin slot, the other is squared. Putting the pin on the squared side will push the gear out a little more.

The only other potential culprit I know of is the actual axle should be seated in the pumpkin area correctly. It's a square design and will go into the axle further when seated correctly. If it's not in all the way, it'd keep the portal from closing correctly.

[mikemcE]

Follow the book , and remove the extra bearing.


Hang up and Drive

[halllon]

Thanks, guys!

[meatmonkey]

Dumb question, could the shaft be machined to accept the "extra" bearing? Just seems weird to allow the shaft to be bearing supported on the outside, but only supported by the spool/carrier bearings in the middle.

[cubalz]

Originally Posted by nielsm

Be aware of the appearance of a space for another bearing on the axle. The directions are correct, but it can look like you'd want to put a bearing there. You should not put a bearing in that side as it could create spacing issues like you describe.

Another issue is the gears have what look like pin slots on both sides. One is a round pin slot, the other is squared. Putting the pin on the squared side will push the gear out a little more.

The only other potential culprit I know of is the actual axle should be seated in the pumpkin area correctly. It's a square design and will go into the axle further when seated correctly. If it's not in all the way, it'd keep the portal from closing correctly.

This is the same question I had when I was building my 10.3. I finally really looked close at the instructions and it did not show a bearing in there but it is strange why it is molded to accept the same bearings as used elsewhere in the axle. Regardless, it works fine anyway

[nielsm]

Originally Posted by cubalz

This is the same question I had when I was building my 10.3. I finally really looked close at the instructions and it did not show a bearing in there but it is strange why it is molded to accept the same bearings as used elsewhere in the axle. Regardless, it works fine anyway

I imagine they thought they needed a bearing there in early design and then decided against it without redesigning the part to eliminate the bearing space. I don't think it causes a structural issue, but clearly can create confusion on the build.

I found since this model has so many bearings and some are very similar sizes, I use a caliper on everything, including screws to be sure I used the right part and double checked the manual images. In spite of the grief, it is still a far cry from what manuals looked like 35 years ago when I build my first RC cars. Back then, rebuilding a step was really common as there was so much lack of clarity.