printable belt tensioner / bearing leveler

[barnett]

This thing lets me use a screwdriver to level the idler bearings at the top of the t-slot towers.
http://www.thingiverse.com/thing:87463

I've only been using it for a few days, but so far, it's been working out nicely.

Barnett

[geneb]

That's really slick.

BTW, you know you've got your idler brackets flipped, right? The laser engraved alignment lines are supposed to be on the inside surface.

g.

[barnett]

Thanks! I don't think I knew they are flipped... or if I did, then I forgot. Should I worry about it?

[JohnStack]

Your device brings up a question:

For the purposes of a troubleshooting FAQ I've been working on...

In your prints, how do you know that your belts need tensioning? What happens to the print?

Obviously, when things are out of whack but what are the early telltale signs?

[barnett]

Someone else probably has a better answer on the effects of belt tension. I know about the squeaking/howling sound when the belt rubs on the side of the bearing.

I've had the belts pretty tight the whole time. Only now that I've setup this leveler thing have I played around with looser belts ... because when I move the carriages with my hand, they are easier to move if the belts aren't super tight. I would imagine too tight may wear out the belts or motor faster and too loose might introduce slop or backlash. I suppose it would easy to test what happens when the belts are looser.

[geneb]

The orientation of the idler bracket is only important when you're first doing the assembly. Check out the draft of the 2nd edition to see how I did the install there. Makes it a lot easier than eyeballing all six of them.

g.

[JakeCShake]

The orientation of the idler bracket is only important when you're first doing the assembly. Check out the draft of the 2nd edition to see how I did the install there. Makes it a lot easier than eyeballing all six of them.

g.

Yeah.....we didn't even have your FIRST manual when building it. It's funny looking back and seeing some of our "mistakes". BTW....second manual looks awesome!!!!

[geneb]

Thanks! Last night I added Dan Barrans(sp?) method of threading the drive belts into the Cheapskate. I show both methods and the builder can work with whichever one works best.

I'm trying to fold in everyone's suggestions that make sense.

g.

[geneb]

btw barnett, one of the things I really like about your design is that it looks like it would be very easy to "balance" the belt to keep it running in the centers of the bearings. If you tweak it a bit to add a nut capture pocket on the bottom clamp, you wouldn't need to worry about having a wrench to adjust it - you could use socket head screws and adjust using a T handled allen wrench...

g.

[barnett]

Thanks, yeah balancing was more important to me than tensioning.

The nut capture idea makes a lot of sense because then the brackets don't have to be so wide. They're kind of extra wide now so my wrench fits in there. At least this way you can use whatever screws/nuts you have handy.

But if I do a V2, I'll use the nut capture idea for sure.

[edward]

Hopefully barnett you won't mind me doing you a favor and creating the v2 with nut captures. There are now 4 distinct pieces for each tower, all appropriately include M3 (that is what I had the most of) nut captures if needed so that it can be installed and adjusted with only a single tool. The top pieces on each side also now have a small pad that centers them in the hole present in the melamine bracket.

http://www.thingiverse.com/thing:146815

Hope you like!

[barnett]

This looks great. Thanks for making these improvements!

[edward]

You did the hard part

All I had to do was constrain the geometry for a few hexagons and watch my printer spit out its own improvements.

[626Pilot]

This is a really slick design. It exploits what's already there and makes it better.