Help!!..wheels?
 

My team is still trying to figure out wat are good cheap wheels that we can use on our robot. We already have andy Mark wheels but the tread wears Away way to fast for Us to be replacing. We also put wagon/pneumatic wheels on our off season project but they had to much traction for our robot to even try turning.so my question is what wheels has your team had success with?

Re: Help!!..wheels?
 

You could get some conveyor belting from McMaster and use that as a covering for the AMs. That's a trick that a lot of teams use.

330 uses AM wheels on the corners and 6" pneumatic casters in the center, running a 6WD "drop" configuration. The wheels are replaced regularly due to lots of use.

Re: Help!!..wheels?
 

If you were having trouble turning, you might look into omni wheels.

Re: Help!!..wheels?
 

or shorten the wheelbase

Re: Help!!..wheels?
 

How strange...

1351 uses AndyMark kit wheels on a six-wheel rocker. We have never had any problems with the wheels except for their weight. Our wheels survived two regionals and one off-season event as well as being driven on concrete to show sponsors.

How much scuffing do your wheels endure?

Re: Help!!..wheels?
 

Include Nationals and offseason presentations!

Re: Help!!..wheels?
 

An alternative to omni wheels on one end and high traction wheels on the other end is to use the relatively hard black plastic wheels typical of caster wheels on one end and high traction wheels at the other end. We have found it to be a very good mix of providing some resistance to being pushed from the side but still providing a benefit of 4 wheel drive. This setup also allows good turning. The black plastic wheels do wear out and sometimes get chunks broken out of them so they typically last 1 - 2 regionals but are relatively cheap and depending on the drive train setup can be easy to replace.

Re: Help!!..wheels?
 

One more thing - Colson wheels work well for the high traction end and they are affordable.

http://rigs-n-wheels.com/store.php?catid=62

Re: Help!!..wheels?
 

Colson wheels aren't bad, but their traction isn't the best either.

If you have access to a manual mill with a rotary table, put some 1/4 inch plate on there, mill it round, punch some holes, then weld it into the center of a 4inch ID aluminum pipe. Poof, High-Tech traction wheels for cheap! If you're missing the Mill part, check out your local community college; many of them have shops and would love to help you out.

Re: Help!!..wheels?
 

The colson wheels are great.

They actually have very good traction. Yes, conveyor belting has far more traction when it is new... but it doesn't stay new for long :cool: Remember wedge-top was designed for handling food.... I hope food isn't as dirty as the FIRST carpets... You'll need to keep replacing wedge-top or rough-top for it to stay fresh.

Colsons don't have this problem. They are designed for dirty environments like shop floors. And when they heat up from friction, they actually gain more traction.

They also wear very well. One set will last you a whole season. And when you're done, just throw the hole wheel away and get a new one! That’s how cheap they are!

Re: Help!!..wheels?
 

^This.

1618 has done this very thing for two seasons--we cut off the tread from the AndyMark FIRST Wheels on our bandsaw, then rivet on incline conveyor belting from McMaster-Carr. The result has been rock solid; two robots, three events, no issues. (We did finally throw one tread during a demo early this year...from our 2007 robot, after the Palmetto Regional, Brunswick Eruption, and several demos.)

Tread costs a couple bucks, the wheels cost $10 each (plus bearings)--but getting the functionality of replaceable-tread wheels for half of the cost is well worth the afternoon of work.

Re: Help!!..wheels?
 

Nitrile roughtop wears extremely well, and is a good compromise for this situation. I still prefer natural rubber or SBR tread, and just changing wheels often. It seems to be worth the traction advantage.

Re: Help!!..wheels?
 

also the weight distribution over the wheels, could be a factor on the quickness of wear,

last years robot was two wheel drive with almost all the weight on the front two, we had great traction, but we couldent turn well, and the tread wore down to nothing after the FL. Regional!

Re: Help!!..wheels?
 

Our team has been looking at Colsons. Last year we had 4-inch IFI wheels with wedge-top for low-weight and low center of gravity, but we also wanted to go fast, so our wheels ended up rotating at about a thousand RPM, and we had to replace a set of treads (that's 6 treads for us) at lunch on practice day, and we've had to replace them again since then. The Colsons are a great solution, at about $5 a wheel, they're MUCH cheaper than almost any other good robot wheel, and they offer a pretty good amount of traction if you get the Performa rubber type, and they also last a LONG time. Two other companies that offer similar wheels are NPC, which are made for battle bots, but are much more expensive and don't have quite the life of Colsons, and Banebots, but their treads wear off like a Firestone tire. These wheels are used in the battle bots world more than almost any other wheel, and most of the people I've talked to love them. If you make a custom hub in the middle out of delrin or aluminum, you can put a key between it and the wheel, and then key it so it fits on a 1/2" or 5/8" shaft, to which you can connect a sprocket. Simple, fewer moving parts (bearings) than the IFI wheels, about the same weight, and very rugged.

Re: Help!!..wheels?
 

That shaft still has to sit in bearings, so I wouldn't say it is fewer moving parts or inherently more reliable.

Re: Help!!..wheels?
 

We press-fit the colsons on the AM hubs and put three 10-32's through the hub plate to secure them.

Works great and takes like only a couple minutes to assemble.

Re: Help!!..wheels?
 

I agree with you here, for wedgetop. Blue Nitrile Roughtop is among the most durable tread materials I've used. Over the 2007 and 2008 season, using the robot for both competition and demos, we NEVER changed our tread on each bot. Never had a problem with roughtop wearing. Wedgetop, on the other hand....

Nitrile rocks. Never had a bad experience with it. Just lay it against an AM wheel that's been stripped of the polyurethane, drill some holes and slap a few pop rivets in. It's janky, but it WORKS.

Yeah, weight distribution is key. I've mostly used roughtop on our 6 wheels, and had no problems there. The closest we got to wearing tread out was on our 2005 Crab Drive, for Triple Play, and that wasn't bad enough for the bot to be at a disadvantage.

Seriously, if you do your attaching right, you can't go wrong with Blue Nitrile (assuming FIRST keeps the carpet....).

Re: Help!!..wheels?
 

If FIRST doesn't stay with it, go with red linatax.

Re: Help!!..wheels?
 

Red Linatex technically has a higher coefficient of friction than Blue Nitrile Rughtop, on FRC carpet. So if a team has the money, go for Linatex every year. It wears insanely well, and is grippy like no other. Only problem is the cost... It's MUCH cheaper to go with Blue Nitrile, at least from the suppliers I've found...

Re: Help!!..wheels?
 

Craig, I was going for the icy floor! Lol.

Re: Help!!..wheels?
 

That would be fun.... Though I'd be a fan of carpet with either a fence or a BIG ramp in the middle... Stack attack style, y'know?


On the topic of wheels, keeping cost under consideration from the beginning is key. If you don't design for your end requirements, not too much point in what you're doing. Billfred brought up some GREAT suggestions. He's cool, so his posts deserve reading extra carefully.

Re: Help!!..wheels?
 

We've used IFI wheels in the past with decent results but the tread is a pain to replace. This year we are looking at the AndyMark Plaction wheels, basically kit wheels with a system for easily using conveyor tread material, and cheap too!

Re: Help!!..wheels?
 

When i went to AndyMark this off-season Andy said that he was new traction for his traction wheels ( to complement his new wheels ) so just talk to andy about alsohe said that his new treads should last 2 regional or even 3 :yikes: .

Re: Help!!..wheels?
 

I'll also throw support to the Colson wheels for three main reasons: durability, cost, and fabrication time necessary.

Durability: There are a lot of offseason competitions in the Northeast every year. Couple that onto the official scrimmage in February, and two official FRC competitions, and one of 228's robots can see eight to nine competitions a year. In New England.

The hard defense played up here really wears down Roughtop fast. We've been able to get an entire season out of a single application of Roughtop before, but after the first competition it already lost a considerable amount of traction. Colson wheels on the other hand (the 5"x2" Performa ones to be exact), went through eight competitions this past year without any noticeable change in performance.

Cost: At between $4 and $10, you will be hard pressed to find better wheels elsewhere for this cost.

Fabrication Time: About ten minutes per wheel, depending on how you do it. The approach 228 uses is to take aluminum rod, turn down the outside to a diameter slightly oversize past the diameter of Colson wheel hole, bore out the inside to axle diameter, knurl the outside of aluminum rod, use cutoff tool to cut off about 1-1.5" piece, use arbor press to broach hole with keyway, and then use arbor press to press aluminum rod insert into the Colson wheel. You now have a completed live-axle Colson wheel.



If dead axles is more your thing, then take one of the thinner 7/8" wide Colson wheels, put it on a rotary table, and drill three-six holes through the wheel, which you can then mount sprockets to.

Sure, they aren't as pretty necessarily as custom machined wheels, but at a final cost of about $10 a piece, ten minutes of machining time, and a sky-high reliability, they can't really be beat. And from an engineering perspective, that's beautiful.

Re: Help!!..wheels?
 

inlflateable wheels, dont wear down very easily......

Re: Help!!..wheels?
 

:) We have also used Skyway wheels, which were part of the KOP in past years. We have doubled them for more traction, and applied belt material to them as well. You can order them with precision 7/8 OD bearings, 3/8 ID bores installed, which really makes them a good deal. I don't recommend the
.906 bearing option, as they are not very good quality.

Re: Help!!..wheels?
 

Depends. 330 goes through a set of center wheels per event, roughly. They also drive the robot to its limits or until they get kicked off the practice field. (The practice robot? Double that.) Those are pneumatic casters.

The other year we used pneumatics was 2004, and we spent most of the time on the bar, so the wheels didn't get a lot of wear.

Re: Help!!..wheels?
 

we've only ever used them for 4wd....why would the middle wheels wear faster than the oustide one? it seems like the corner ones would have more scrubbing on the floor surface when turning

Re: Help!!..wheels?
 

I never said the middle ones wear faster than the outside ones. Guess what else gets replaced at an average rate of once per event?

Re: Help!!..wheels?
 

We're looking at using 1/2" cantilevered dead axles again this year, and I notice that Colson wheels are available with a 1/2" bore bearing or bushing, although it's not the most common hole size for them. Instead of using a rotary table, maybe we could put a bearing into a sprocket, bolt it to the wheel with a 1/2" bolt, and use the holes in the sprocket as a template for drilling the holes in the wheel, bolt the sprocket to the wheel with the 3 or 6 small bolts, and then leave the bearing in the sprocket to keep the sprocket concentric with the axle on the robot.

There seem to be several different types of tread avaiable, do you have experience with some of the different ones, and recommendations?

Re: Help!!..wheels?
 

You could buy those if you were so inclined (although they aren't cheap).

The proccess you described is exactly what we do, 3 bolts is all you will need.

You want ones with "Performa" tread, which is just about all of them. I don't think it matters what color they are.

Re: Help!!..wheels?
 

it would be a long list.........

Re: Help!!..wheels?
 

We have used the colsons from robot marketplace before with great results and they seem to offer very good traction in FIRST. Does anyone have the cof of the colsons on carpet as compared to roughtop. Also how would they do on a slick plastic surface.

Re: Help!!..wheels?
 

Not for 330... Batteries once a match, wheels once an event unless there's a really good reason to do it faster.

Re: Help!!..wheels?
 

Ok so I have been thinking about the subject of wheel choice in relation to drivetrains I have been designing. All of my designs this offseason have used custom treaded wheels with roughtop. We have in the past used colsons with very very good results, and had a robot that no one could push using 6 2" wide colsons and AM shifters. Now the dilemma... We can buy colsons for about $6 and then machine hex keyed hubs for them for a total price per wheel of probably $7.50. The weight of the wheel plus hub would be right around 3/4lb. Now all of the custom wheels I have designed weigh slightly more than 1/2 lb with tread and would cost around $10 per wheel in material. The big dilemma comes from the need to change tread frequently with roughtop versus never having to with colsons. True roughtop does have higher traction than a colson wheel; however, how much of a difference is it really. Also colsons are designed to work on dirty surfaces and they might work better on a plastic surface (HDPE) as well. Given these factors what would a team choose?

Also I have been strongly considering a 8wd west-coast style design for the upcoming season. Going with Colsons would negate the benefit of quick wheel changes so the only noticeable benefits of a west-coast style drivetrain would be slightly improved lateral stability and possibly less weight. So question number 2. If we go with colsons, would there be any benefit in going with a west-coast drivetrain?

Re: Help!!..wheels?
 

we never replaced the tread on our IFI wheels

all the way through the, FL. regional, TNT,and the robot rodeo.



I think the game(maybe not the game but how you have to drive the robot in the game) also has to do with the wear pattern.

with Overdrive and turning left, we lost the right side tread twice as fast the the left.......