Mounting Sprockets to the Rover Wheels

[BJT]

I like to use a 10-32 bolt that puts about 1 inch into the wheel. we run a tap in about .75 inch. The last .25 without threads makes it nice and tight.
I have just run them in without tapping but then they can't be disassembled without the threads getting screwed up.

[Tom I]

We ended up just drilling out the holes in the AM wheels and putting 10-32 bolts through with aircraft nuts.

And yes, Loctite DOES melt certain thermoplastics! I'm not sure if the wheels are thermoplastic, but team 811 is not gonna risk it (again!)

[artdutra04]

The wheel hubs are black polycarbonate.

Loctite dissolves polycarbonate.

Therefore, if you use Loctite to mount sprockets or hubs to the wheels, you will dissolve the plastic.

Use nylock nuts or split lock washers instead.

[Gdeaver]

With the thickness of the spacer and sprocket, a 3/4" bolt would not penetrate very far into the hub. As many have pointed out it's best to either put a bolt all the way through and use nuts or use long enough bolts to almost go thru and tap them in. When the robots are on carpet and they take a side impact, the stress is distributed to all the wheels. With drifting this year the robot can hit the carpet with only 1 or 2 wheels taking the impact.
Beware of the carpet.

[gorrilla]

Originally Posted by artdutra04

The wheel hubs are black polycarbonate.

Loctite dissolves polycarbonate.

Therefore, if you use Loctite to mount sprockets or hubs to the wheels, you will dissolve the plastic.

Use nylock nuts or split lock washers instead.

have you ever experienced this first-hand?

I would like to see some pictures,(besides this one, http://www.chiefdelphi.com/media/photos/17114)

nothing on the loctite website says it does(at least from what i can find)
http://www.loctiteproducts.com/

[Daniel_LaFleur]

Originally Posted by gorrilla

have you ever experienced this first-hand?

I would like to see some pictures,(besides this one, http://www.chiefdelphi.com/media/photos/17114)

nothing on the loctite website says it does(at least from what i can find)
http://www.loctiteproducts.com/

Try looking here

[Kraftyman]

Greetings,

Please - so much strange information posted here. I am a plastics engineer and I have never heard of using Locktite on plastic - not because it will melt the polymer. Because locktite does not do much good with plastic. locktite is a chemical bond used with iron based metals. Other grades can be used to prep aluminum so that it can be bonded - but do not use with plastic as superglue would do just as well....... Good luck.

[sanddrag]

We tapped ours 10-32 with a cordless drill, and it works just fine. Not worried about cracking or stripping anything.