Hi guys!
We are looking to move towards plaction wheels… (yes, we are a new team and we haven’t used plaction wheels on the drive yet)
Now we are going to be working on a solid driving base off-season, and we are getting new wheels.
But what are the differences between the andymark plaction wheel and IFI (now VEX PRO) wheels?
We’ve used both in our history. AM Plaction wheels are the lightest out there but with that comes weakness. Our 6" Plaction wheels in previous seasons and on our practice robot this year are constantly cracking either on the spokes or around the rim that holds the treads. If you use them, plan on getting backups and make sure they are easy to swap out. If you need their combination of COF and weight, though, they are the only game in town.
IFI wheels are fine but you don’t see them used much anymore being a bit old school. They won’t ever fail catastrophically like the Plaction wheels will. About all they can do is bend.
We went to the AM Performance wheels for our competition bot and have been delighted with their performance plus they look great. They are a bit heavier and more expensive, though.
The big differences are material/weight and tread integration (both have replaceable treads).
Material
IFI: aluminum
AM: polycarbonate - AM also sells aluminum performance wheels with a different hub design than IFI. These are also lighter at each diameter than the IFI versions.
The IFIs are heavier than the AMs at every diameter (4", 6", 8") - difference increases with diameter.
I haven’t noticed any difference in performance based on the material.
Tread Insertion
IFI: around wheel perimeter only
AM: inserted between the two wheel halves which are unscrewed by 6 bolts (fewer wheel-tread attachments needed)
Tread Attachment
IFI: rivets (only?), tread is simply riveted on the outside - this is a real pain for some team/drivetrains
AM: lacing or screws - we like this 
Width
IFI: 1", 1.5", 2"
AM: 1" only
Treads
I believe the treads each company sells may be used on the others wheels. We’ve done IFI tread on Plactions, though it’s a little tougher.
IFI: IIRC, they’re slightly thicker with like an extra layer of backing on them.
AM: Anecdotally, we feel they wear better and may have slightly higher CoFs.
They’re sold differently in terms of bearing options and sprockets, but I don’t think there’s actually a bearing ID or a sprocket tooth count (#25 or #35 chain) that you can achieve with one but not the other. I may be corrected, though.
The IFI wheels also have the tread sit between the sides of the wheel.
We’ve used both in the past two years.
I’d recommend IFI wheels even though they are more money. We had some problems with plaction wheels breaking for several reasons. One major reason was that since they are a plastic hub you can’t use loctite on the nuts (bad lesson learned) while you can on the IFI wheels (metal hubs!). We have also had problems after extensive use the plactions wheels will develop small cracks when exposed to harsh surfaces/falls. This year’s bump didn’t agree with a few of our wheels. They didn’t cause a wheel to fail, but we switched them out as a precaution and won’t use the ones that get damaged on a competition bot, practice only! I also like the tread attachment on the IFI wheels more. We had a few plaction treads come off during competition. The combo of rivets and compression that holds the tread in is very robust in the IFI brand!
As for integration, they are both the same. You can use the same sprockets both #25 and #35 and axles on each one.
Overall plactions will get the job done for a fraction of the cost but they are less durable than IFI wheels! As mentioned above, IFI wheels do come in varying widths which I hope our team can use in the future for more grip/pushing power.
We’ve never had a problem with either wheel, including direct impacts on 6" plaction wheels going over the bumps in 2010. I’ll also note that we use lock nuts in lieu of Loctite.
Plactions are nice because they’re very quick to put together and they’re inexpensive. We’ve had some slight problems with inner bearing housing flex after several competitions, but that was after 4 competitions.
IFI’s are nice because once they’re put together, you’ll never have a problem with the wheel itself. Their assembly is made easier by substitution of Phillips head machine screws in place of the button head bolts that constantly strip. They’re a nice weight for their strength. They also come in 1.5" and 2.0" widths for only slightly more weight, whereas the Plaction wheels need PVC and longer bolts to achieve greater width.
My fault, I meant the wheel perimeter (or rather, surface) itself does not change to accommodate the tread–i.e. it doesn’t open as the Plactions do.
I’ll also note that we used the 4" Plactions on the end of co-axial pivot modules for crossing both the 2010 bump and the 2012 barrier (and the 2011…field). No problems here, they’re some serious wheels. I’d be interested to know how one could crack them. We’re still constantly running the 2010 robot (falling off our practice bridge…) with no issues.
We’ve noticed that the plastic grooves on the Plaction wheels cuts back on the coefficient of friction a little bit. We’ve run Performance wheels and had a noticeably “stickier” drive. I’ve never used an IFI wheel but I believe the groove is smaller, so you should have a touch better traction.
If you do some testing you should see no difference between 1" and 2" wide. You are providing a bigger area but with the same total downward force (weight of robot) spreading over that larger area you don’t gain. Traction is a tricky thing and some controlled tests can be cool.
To the op, we have used and had good success with all. We are using the am 4" performance wheels right now with blue tread from mcmaster. It is a little gripper than am or IFI tread but only comes in wide sizes so it has to be cut (I think 3" is the narrowest)
colsons are another option and are much more durable than ifi/andymark plaction wheels.
I’ve had experience with both IFI Traction wheels and AM Plaction wheels, neither are a bad option, it really comes down to preference.
IFI’s are nice because of some of the features noted above; they’re essentially bulletproof for FRC applications, come in wider standard widths and are an IFI product. (Who doesn’t love IFI?)
Plactions are great because they’re less expensive and lighter, but their standard method of tread attachment leaves something to be desired and they can have robustness issues. In my first experience with plaction wheels, the team I was on decided to try to use them without anything to retain the tread ends (Just relied on the grooves in the wheel body to retain the treads) and we started losing treads after an hour or so of practice. Since then, I’ve always shot a rivet into each free end of the tread and one ~180* opposite of where the tread meets. Seems to solve the problem easily. One of the things that many people seem to forget/overlook about plaction wheels is that it’s possible to make a plaction wheel of any reasonable width that you can think of - it’s just a matter of cutting a piece of Sch40 PVC (Diameters escape me at the moment) to the right length and getting the right screws.
My only complaint about plaction wheels is that they can’t accept a 22T Sprocket #35 plate sprocket directly without a spacer. This isn’t a deal breaker for most teams, but can add an unneeded hassle if you’re not expecting it. Also, I’ve always drilled out the sprocket mounting holes with a #9 Drill Bit (Through hole for a 10-32) and then used a 10-32 SHCS with a Lock Nut to retain the Sprockets as I’ve never been a fan of shooting self tapping screws into the wheel body.
The most trouble we’ve had with AM wheels and treads was in a crab drive; some treads fell off, some got ripped up and lost the outer layer of tread (granted, this was by the fall and would most likely have happened regardless of the wheel).
Anyway, my reason for posting. We have never (to my knowledge) broken a 4" or 6" plaction wheel, but on our 2010 bot during a demo at the state fair, we destroyed two pairs of 8" plactions. Apparently our driver was excited and took off over the bump, came down and bent and snapped the spokes in the plastic wheels. I wonder if we have a picture of them… I think the smaller wheel sizes are plenty strong; the larger ones may be comparatively weaker, I don’t know for sure.
Maybe, but we’ve rolled a robot down the 2010 bump onto 8 inch plaction wheels (which would likely involve the robot being supported by the side of the wheel at some point, which it probably wasn’t designed for) and they were just fine. And that was just one impact out of many. The biggest issue with placation wheels seems to be that teams are too reliant on their precious liquid thread-locking products when nylon insert lock-nuts work just fine.
How are you attaching the treads? We haven’t lost a tread since we started screwing them on (though there were a few other less-implementable solutions). We do wear them down eventually–but usually when we do something like loose a steering sensor or otherwise accidentally drag a wheel while it’s out of alignment. We just switched our treads on the 2011 bot, and one of them was still alright (the others had been abused as above).
I guess I wouldn’t be surprised if the 8" plactions were noticeably less tough than aluminum wheels, though I don’t know if there’s a difference between the AM and IFI versions. I’m surprised anyone has trouble with the 6", though, and we’ve put our 4" through so much I don’t know what on the FRC level could take them out. Bumps, barriers, dropping off bridges, tipping back onto its wheels, I think we dropped the 2011 one off the cart once…
A single drop of Loctite + any of the things you described above
Yeah, we have never had a problem with the bolts. (Well, sometimes they’re really hard to undue (so nylocks are nice, too)…) The main complaints here seem to be about the polycarbonate shattering.
While I understand the thread is AM Plaction vs. IFI Wheels, for a dead axle wheel, I can not recommend Colson Performa wheels enough. I may sound like a broken record by now but… We have run them for the last two seasons and I don’t intend to use any other wheel again unless absolutely mandatory. The cost to go to a Colson wheel is less than an AM or IFI, the hubs are available through West Cost Products.
How are AM performance wheels compared to IFI wheels?
Although they are called “performance” wheels, they generally have the same advantages/disadvantages of plaction wheels. Though they can be used easier in a live axle setup than plaction/iFI wheels.
The performance wheels have noticeably more grip, partly due to lack of a draft from the molding that occurs in plasticon wheel manufacture, but also because the aluminum rim is not as large, and contacts the floor less than the plasticon retaining ring. I would go with performance wheels any day, as long as you keep to the 4 and 6 inch sizes they are not that much heavier or more expensive.