Plaction wheels Vs. the bridge (after 3 comps)
 

Hey guys. After a 2 regionals and the state championship, our robots center plaction wheels took a beating. Our robot was able to get on the bridge with a ball stuck under it but that raised the bridge and the center wheel took the edge of the bridge head on. So here is the picture of what happened to our plaction wheels after 2 seasons.
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Any other team have this happen?

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

1058's plaction wheels are in rough shape through 5 competitions. It's lost a lot of it's original grip, but they still work well. I'll get a picture soon and add it here.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

Ouch. That looks rough. Never seen that happen to Colsons, though.

Just sayin' :rolleyes:

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

We used pneumatic tires this year, but last year we used 6" plactions. After champs we took our bot to do a demo at our sponsor's company bbq and drove it pretty hard on the asphalt. Resulted in most of them being cracked to some extent.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

Actually it should be 3 reg 1 state comp and a couple off season events. Its been through a lot of games and very agressive driving.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

We had the same thing happen. We were fine after our two regionals but broke both our center wheels at Championship. We moved to center colsons for our off-season and didn't see any problems. That's probably our plan for next year.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

I have a quick question, did you use any lock tite on these wheels any where?

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

I wouldn't think so because the locktite generally is used on bolts in the hub but in the photo the hubs all seem intact.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

No. The hubs were fine just the loss of plastic and a couple cracks. The bridges this year did a number on the wheels. But they still supplied the grip needed for getting the bot up the ramp (or push another robot up)

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

We used plactions this year (normally make our own 2 piece aluminum rims) due to time/budget constraints since we used 8 in. ones.
We never had any issues after 4 events this year, and extensive practice during the summer in preparation for IRI with a new drive team.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

Did you guys traverse the barrier by driving into it?

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

No it was hitting the bridge with a ball jammed under it raising the bridge up and then the center wheels would make contact with the not so soft edge of the bridge. Never went to the barrier.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

I can attest to this as well. Our 2010 plaction wheels (8 wheel skid steer) worked incredibly well - but we never once went over the bump. We never saw a crack.

This year (6 wheel drive skid steer) we never went over the bump. We used the bridges. We saw the exact same failure mode on every single wheel (24 of them). The outer lip used to retain the tread side to side cracks. This fracture propates, and many times will propogate through the rim. We drilled and riveted the tread on as the lips were all broken off our wheels. We have many with no lip at all now because it's all fractured off.

We have NEVER seen a spoke break or fracture.

The wheels appear to need a redesign: the rim and lip need to be significantly beefed up, and the spokes can be lightened to save some of the added weight from the rim and spokes.

I think I'm going to push for the new KOP wheels to be used next year - having a wheel that tread can come off would be nice.

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

From what I see is the plastic on the lip of the rim seems very cheep and thin, After seeing this if our team uses plaction in the future I will definitely move for using aluminum rims

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

It's better than Mechanum wheels vs. 2010 bump... We destroyed 4 sets of wheels, haha

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

Are there any teams who had mecanum drive this year who suffered major damage against the bridge and/or bump?

Re: Plaction wheels Vs. the bridge (after 3 comps)
 

For years First teams used Skyway wheels. If you go to their web site you can get an idea of all the options. Many of their hub designs have reinforcements that would help with the type of damage shown. I always liked the Skyway wheels. Never had any problems other than making hub adapter doughnuts. Many tire options. This year we went with Colsons, but gave Skyway a serious look. http://www.skywaywheels.com/ Looks like from the website they also want to support FIRST.