Help!!..wheels?

[artdutra04]

Originally Posted by Hachiban VIII

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 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!

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.

[gorrilla]

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

[Teched3]

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.

[EricH]

Originally Posted by gorrilla

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

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.

[gorrilla]

Originally Posted by EricH

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.

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

[EricH]

Originally Posted by gorrilla

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

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?

[gorrilla]

Originally Posted by EricH

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?

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

[sdcantrell56]

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.

[EricH]

Originally Posted by gorrilla

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

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

[sdcantrell56]

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?

[gorrilla]

Originally Posted by EricH

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

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.......

[MrForbes]

Originally Posted by artdutra04

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

......

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.

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?

[=Martin=Taylor=]

Originally Posted by squirrel

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?

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.