New AndyMark am-0939.Do they work or not?
 

1730 is looking into new AndyMark 0939 4" performance wheels that require a zip strip to hold the tread on. Has any team out there had any success or failure with them? We are worried that the gap in tread will give the robot a weird ride.

On a side note, is there any way to obtain 1/2" hex bearings on this planet? AndyMark had them in stock and then ran out before we could hit submit on our shopping cart! :confused:

Re: New AndyMark am-0939.Do they work or not?
 

We have the 4" performance wheels on our 4WD WCD bot this year, no problems. The key is to get the tab length correct, but even then it's no big deal so long as the students aren't too aggressive with the sanding.

Re: New AndyMark am-0939.Do they work or not?
 

These wheels are based in part on the design 971 used last year, so our team has a fair amount of experience dealing with wheel like these.

Originally, when we cut the tread, there were large bumps where we stuck the tread in the slot. The result was a noisy robot more than weird driving, but it would really depend on your drivetrain. Another factor is that we had our wheels be less than 4 inches, so there might be less of an issue with the 4 inch ones.

Make sure you shove the tread in as far as it can go. Cutting small slits in the tread rubber where the tab ends and the tread begins can also help make the bump less of an issue. A 1 cm long cut on a band saw should do the trick. We got our tread making down last year so that there was little, if any difference between the slotted wheels and normal wheels.

Overall, I would highly recommend this method. Tread changing for us has never been easier.

Let me know if you have any more questions.

~Kevin

Re: New AndyMark am-0939.Do they work or not?
 

Would you be able to please post a couple pictures of that part of the wheel with a tread installed as you describe here on CD? We are planning to use the wheels, but from what we have assembled so far, I'm concerned. I presume that if we can see a detailed photo of what you have done (maybe one with an angle looking mostly at the tread, and one with an angle looking mostly at the part that is pulled through and connected with the zip tie), we'll be able to better understand what we're doing wrong.

Thanks!

Re: New AndyMark am-0939.Do they work or not?
 

I will work on finding relevant pics. I can also create some diagrams if I can't find any pictures that illustrate the key parts. It might take a little while, as it's still pretty early out west here.:) I can do it within a few hours.

Re: New AndyMark am-0939.Do they work or not?
 

We will be using this exact wheel in our climbing system.
Let's just say, 4" dia. is with tread attached. Keep that in mind when you do your calculations.

Re: New AndyMark am-0939.Do they work or not?
 

Try WCP. VEXPro is unfortunately currently out of stock as well.

Alternatively, you can take a shot at turning the ends of the hex shaft down and use a standard 1/2" bearing.

Re: New AndyMark am-0939.Do they work or not?
 

The tread attachment will work fantastic. Its a very solid design and teams should give this new idea a try. We ran a wheel to test on our 2011 bot in the offseason. Worked very very well.

-RC

Re: New AndyMark am-0939.Do they work or not?
 

The best pictures we currently have of the wheels with tread installed are here and here

There's also a series of images from SVR where we showed Andy Baker how to install the tread that can be found on our Picasa site.

Re: New AndyMark am-0939.Do they work or not?
 

Do the pictures on this page's "How to / Pictures" tab help?

Andy

Re: New AndyMark am-0939.Do they work or not?
 

Thanks Evan. The key is also making sure the tread is tightened very well with the ziptie. Use some pliers to make sure you tighten it all the way. Hand tight zipties are not tight enough.

~Kevin

Re: New AndyMark am-0939.Do they work or not?
 

I have attached a rudimentary drawing on how to create tread for this style wheel without a gap in it. It involves creating slits where the tab meets the tread to close of the space when it is shoved into the slot on the wheel. If you have any further questions on this method or the wheels, please don't hesitate to ask. I'd love to see teams try out this new wheel style.

My paint skills are not great, but if teams are interested, 971 can create a step by step guide on how to do this. Please give me feedback if you want to see this happen.

~Kevin

Re: New AndyMark am-0939.Do they work or not?
 

Our team is using them for our 6WD this year. We're using them with some blue nitrile tread from McMaster, and initially had some issues fitting both tabs through the hole. We ended up solving this by shaving down the tabs a bit. After that, they fit very nicely and have been working great on our practice bot.

I only work part time on drive train, but after we figured out how to install them, they've been absolutely fantastic. The tutorial on Andymark certainly helped us figure out the basics.

Re: New AndyMark am-0939.Do they work or not?
 

WCP does not have any hex bearings to...