1 (edited by 2n2r5 2013-08-10 04:37:37)

Topic: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

This is an openSCAD adaptation of http://www.thingiverse.com/thing:112718. I added a few options like ability to add more than 3 bearings, variable bearing size, variable smooth rod size, customizable mounting holes and more.

You can preview the file using the Web Viewer.

The customizer will work for Solidoodles however, the script can be altered to work with all types of mounting solutions. See below for help selecting standard bearing sizes. Your bearing nut size is whatever size screw need to hold the bearings.

I won't be uploading this to thingiverse until Wednesday at the earliest. I am still waiting on a few parts. I just wanted to get this up here in case anyone felt like testing it out.

Suggested Print Settings:
* .15 mm layers or smaller
* 3 perimeters minimum
* 100 percent infil*

*There is a lot of force on the bearings and corresponding bolt. I have observed that over time, the heat will build up and cause the bearings to get looser. Also, the plastic will flex and degrade if the infil is too low. The bolts that hold the bearings in need to be very tight. In order to tighten the bolts up with out the nuts ripping through the plastic, you need to have 100 percent infil.


Standard bearing sizes that this will work with: (list derived from Bearing Works)

PN ID OD Width
603 3 9 3
604 4 12 4
605 5 14 5
606 6 17 6
623 3 10 4
624 4 13 5
625 5 16 5
626 6 19 6
633 3 13 5
634 4 16 5
635 5 19 6
636 6 22 7
673 3 6 2
674 4 7 2
675 5 8 2
676 6 10 2.5
684 4 9 2.5
685 5 11 3
686 6 13 3.5
693 3 8 3
694 4 11 4
695 5 13 4
696 6 15 5

http://2n2r5.com/pictures/printer/show-n-tell/threadless_ball_screw.png

Note: The band at the top of this picture is due to some heat build up. That is the first solid layer and it tends to warp for my if I don't have a fan. The cylinder behind this did not exhibit the same degree of banding which leads me to believe it isn't mechanical.
http://2n2r5.com/pictures/printer/show-n-tell/happy_now.jpg

Post's attachments

threadless_ball_screw.stl 270.66 kb, 23 downloads since 2013-08-10 

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SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

2

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Awesome, I was surprised the thingiverse one wasn't parametric.

I have a smooth rod and coupler coming in the mail right now, pretty interested to see how well this mod works. Will report back.

3

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

I got my eye on this and the "M3 threaded rod" mod both are very interesting

4

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

I updated the file to the latest revision. I keep changing my mind as to which direction this needs to spin. I think the picture above is right. Some please let me know if it isn't.

When setting your options, it seems that most people try to set the bearing angle to somewhere around 10 Degrees. I have it being set by the desired pitch. I have it output both so you can dial it into 10 degrees if you want.

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

5 (edited by 2n2r5 2013-08-01 05:37:45)

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Update:

I have found a pretty good combination of 625zz bearing and 8MM smooth rod. The first print of this iteration I forgot to expand the mounting holes so I was unable to mount this flush to the bed. It works great none the less. As soon as I test out the final for this combination I will post it's STL and BOM for anyone that wants to duplicate it. I will also be putting up video and pictures of my test prints soon.

http://2n2r5.com/pictures/printer/show-n-tell/threadless_screw.JPG
http://2n2r5.com/pictures/printer/show-n-tell/Prototype_inuse.JPG

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

6

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Whoa it works!! That is uber sweet!! Notice any slipping?? Have you found a weight limitation?
Awesome job

7

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Video or its just photshop wink

Looks great, but lets see it in action.

8

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Awesome job, can't wait to see more with this.

9

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

I'm trying this mod out right now, getting the rod cut to the right length before I can install it. Will tell you how it goes.

10

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

wow.. thats awesome! what did you change your steps to in the EEPROM for this?

11 (edited by 2n2r5 2013-08-01 19:28:07)

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

This is just the proof of concept test. There are no nuts on the screws holding the bearings in for this test so the bearings are a little looser than they will be for the practical application. There is a little slipping at the end as a result. Otherwise this is working pretty well. Disregard the big heater cable that is poorly run. That was a super quick mod that I didn't feel like dressing in yet.

*** Warning *** turn your volume down. The noises are annoying.

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

12 (edited by 2n2r5 2013-08-01 19:42:36)

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

downeym wrote:

wow.. thats awesome! what did you change your steps to in the EEPROM for this?

I changed mine to 1422 because I am using 4.5 steps/mm pitch and have 1:32 stepper drivers. If i bump this to 5 the world would be happier and I would end up with a number that makes more sense.

You can calculate your steps per mm here.
http://calculator.josefprusa.cz/#leadscrew

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

13

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

That looks great man.  I would do this but I am probably not going to keep my SD3 after I build my delta.  started ordering some of hte parts I need for it big_smile

14

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

I see.. seems straightforward. Are you using a nonstandard driver board? I thought the soldidoodle control board normally uses 16 microsteps.

So for a standard solidoodle driver that would be (200 steps/rotation*16 microsteps) / (4.5mm/rotation) = 711 steps/mm ?

have you tested repeatability with a dial indicator yet?

15

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

downeym wrote:

I see.. seems straightforward. Are you using a nonstandard driver board? I thought the soldidoodle control board normally uses 16 microsteps.

So for a standard solidoodle driver that would be (200 steps/rotation*16 microsteps) / (4.5mm/rotation) = 711 steps/mm ?

have you tested repeatability with a dial indicator yet?


Hey downeym,

I do not have the standard drivers in there anymore. I am using DRV8825. They do 1:32 microstepping. I am also not using the standard motherboard. I am using a Arduino Mega2560 with Ramps 1.4. I don't have a lot that is standard any more tongue.

I will test repeatability tonight. I totally forgot to print myself a new dial indicator mount that will work with the E3D. I think someone just posted one in the MK5 Accessories Topic. I will print one off tonight and post the results. I am also going to check for z-wobble at some point but results are kinda speaking for themselves here. I have a z-wobble test print going right now.

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

16

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

These are some calibration cylinders that I printed off at .2925 layer height. I stopped them part way through to start another print. These a raw results. I have not calibrated anything yet. I still need to calibrate flow rate and do a precise calibration of my z steps/mm. That being said, this looks pretty :-)

http://2n2r5.com/pictures/printer/show-n-tell/early_results.JPG

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

17

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

nlancaster wrote:

.. after I build my delta.  started ordering some of hte parts I need for it big_smile

+1
May I ask which one?

18 (edited by Tomek 2013-08-02 15:03:39)

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Nice, I like this.

I heard one issue with these for industrial applications is the repeat-ability of the 'nut' construction. Not that it's not repeatable in use, but that for each one you make you might have a minute but significant enough difference difference in the rev/mm ratio.

No problem for our application though! smile We  basically have to calibrate everything anyway tongue

19

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Tomek wrote:

Nice, I like this.

I heard one issue with these for industrial applications is the repeat-ability of the 'nut' construction. Not that it's not repeatable in use, but that for each one you make you might have a minute but significant enough difference difference in the rev/mm ratio.

No problem for our application though! smile We  basically have to calibrate everything anyway tongue

I could see that. There are a lot of things that would affect these. You could print the same STL twice and end up with 2 different results. Layer height will affect the overall accuracy of of the angle. When I printed this at .3mm layer height, the bearing cutout consisted of 3-4 layers only. When you print this at .1-.2 there is a much more gradual step between layers.

Like you said though, for our application these work well enough after calibration. I just got my printer back up and running after a small disagreement with my printer. (nothing to do with this project) More updates coming tomorrow.

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

20

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Update:
Suggested print settings added. I also updated the script to the most up to date version. Testing of this system is going fantastic except for what I believe to be a completely unrelated layer shift issue. Even at .3mm this is looking very promising! I am running the same print at .1mm layers now.

http://2n2r5.com/pictures/printer/show-n-tell/results3.jpg

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

21 (edited by 2n2r5 2013-08-10 04:27:30)

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

I know I haven't been posting much but I thought that I would put this photo up showing some of my results. I have been trouble figuring out the best temp for this filament so I have 1 bad spot in the owl where layer adhesion was an issue. Otherwise, everything looks great. I am waiting for my girl friend to give me my DSLR back so I can show off some good prints. I hope this cell phone photo works until then.

http://2n2r5.com/pictures/printer/show-n-tell/sample_prints.jpg

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

22 (edited by 2n2r5 2013-08-10 14:44:50)

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Added the STL of the threadless nut I am using to the original post. Please follow the print suggestions in the original post. The stl is for the aluminum bed.

BOM:
3 M5 x 20 or 15 McMaster
3 625ZZ Bearings Amazon
3 M5 flat washers McMaster
3 M5 Nuts McMaster  Amazon
4 M3 x 10 cap screws McMaster
300 mm of 8mm Smooth Rod McMaster
5mm - 8mm Coupler (flexible or fixed)

http://www.thingiverse.com/thing:130781

McMaster
http://www.mcmaster.com/order/rcvRtedOr … lnktyp=lnk

Amazon- My Wishlist (do not buy for me smile )
http://amzn.com/w/2IPMDMP8UQQ3W

The total order should be about $35 + shipping.

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

23

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

Very impressive..

24

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

how do you control the bearing pressure on the drive rod?

25

Re: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)

johnforeman wrote:

how do you control the bearing pressure on the drive rod?


You don't need to control the pressure. This is a fixed bearing system. After the initial tightening you should only need to occasionally check to make sure the bearings are snug and the mounting screws are snug.

How the bearings get tight on the rod:

  • Start with the bearings loose with about 5 mm above the body of the nut.

  • Slid the rod through the center of the nut (this is possible because the center of the bearings are not yet centered with the hole since the bearing are mounted at an angle)

  • tighten each bearing 1 turn at a time until they reach the body of the nut. (this will align the center of the bearing with the middle of the smooth rod creating the tight fit)

    -For good measure I have cheated each bearing towards the smooth rod by .4 mm. This should make for a VERY tight connection.

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.