26

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

I'm suffering the vertical banding, but its not belts.. its the Extruder.

Basically its 'splodging' filament, at a specific frequency which causes the banding.. if you print a single walled cube you can see its actually wall thickness that changes... I'm chasing down the specific source still, but thats what it is...

27

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

I have a couple new hobbled gears for my extruder. They are slightly smaller than the one that I am using now. If I the vertical banding is from the extruder then this should at least change the spacing of the banding. right?

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.

28

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

yup.

but just changing print speed and/or the extruder max-travel rates changes it.

If you dial up your filament flow, it will also disappear - at the expense of wall accuracy sad

29 (edited by 2n2r5 2013-06-19 04:17:16)

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Bump, Anyone try this yet?

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.

30

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Not yet, cause I need to redesign it to work with an Aluminium Bed and just haven't gotten around to it.

Any chance you can redo it with an 18mm X-Axis center-to-center offset between the screws... pretty sure its the same dimensions in the Y-axis.. but if you are open to doing an Aluminium version you can confirm the screw hole dimensions off of my Alu upgrade http://www.thingiverse.com/thing:89744

31

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

adrian wrote:

Not yet, cause I need to redesign it to work with an Aluminium Bed and just haven't gotten around to it.

Any chance you can redo it with an 18mm X-Axis center-to-center offset between the screws... pretty sure its the same dimensions in the Y-axis.. but if you are open to doing an Aluminium version you can confirm the screw hole dimensions off of my Alu upgrade http://www.thingiverse.com/thing:89744

Here ya go. I just used the same bold pattern as your upgrade. You say 3/8" for your rod size on the thing-i-verse page. Is that right or is it the 5/16" rod that the old one uses?

I purchased an aluminum bed so I could test this and a couple other upgrades I am working on. So, I will have a 5mm version done soon.

Post's attachments

516in_thread_adaptor_slop - aluminum bed.skp 165.54 kb, 9 downloads since 2013-06-19 

516in_thread_adaptor_slop - aluminum bed.stl 665.34 kb, 55 downloads since 2013-06-19 

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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.

32

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

2n2r5 wrote:

Here ya go. I just used the same bold pattern as your upgrade. You say 3/8" for your rod size on the thing-i-verse page. Is that right or is it the 5/16" rod that the old one uses?

I purchased an aluminum bed so I could test this and a couple other upgrades I am working on. So, I will have a 5mm version done soon.

Cheers.. will get around to it tonight or tomorrow. And yeah, typo there on thingiverse, thanks, and working in damn fractional units which doesn't gel well wink

I have the original rod I can swap back to, but have been running an M5 for the past week and a half or so to much success... So will be keen to see a 5mm version too smile

33

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

adrian wrote:
2n2r5 wrote:

Here ya go. I just used the same bold pattern as your upgrade. You say 3/8" for your rod size on the thing-i-verse page. Is that right or is it the 5/16" rod that the old one uses?

I purchased an aluminum bed so I could test this and a couple other upgrades I am working on. So, I will have a 5mm version done soon.

Cheers.. will get around to it tonight or tomorrow. And yeah, typo there on thingiverse, thanks, and working in damn fractional units which doesn't gel well wink

I have the original rod I can swap back to, but have been running an M5 for the past week and a half or so to much success... So will be keen to see a 5mm version too smile


Then I will fix one up 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.

34

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

2n2r5 wrote:

Then I will fix one up now.

Top stuff - thanks very much. Just use the previous model for the rod center dimensions... the M5 passes right through the center of the old 5/16" threaded boss on the Alu platform...

35

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

adrian wrote:
2n2r5 wrote:

Then I will fix one up now.

Top stuff - thanks very much. Just use the previous model for the rod center dimensions... the M5 passes right through the center of the old 5/16" threaded boss on the Alu platform...

That might be an issue then. If the m5 wobbles too much and gets caught up in the 5/16 thread, it might affect the functionality. Then again, maybe it won't. Here are the 5mm aluminum bed files. I will hopefully be testing this out myself by the weekend if I can get my bed in time.

Post's attachments

5mm_thread_adaptor_slop_anti-backlash - alu bed.skp 255.19 kb, 7 downloads since 2013-06-19 

5mm_thread_adaptor_slop_anti-backlash - alu bed.stl 732.25 kb, 30 downloads since 2013-06-19 

You don't have the permssions to download the attachments of this post.
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.

36

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Is there an M3 version yet?

37

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

saymo606 wrote:

Is there an M3 version yet?

I promise that I will make one tonight. Ping this thread if you need to.

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.

38 (edited by 2n2r5 2013-06-20 05:20:01)

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Here are the files for the M3 slop nut that I promise. This is an anti-backlash design. Fitment requires a little finesse to make sure you are tight enough for it to work but still let the rod spin smoothly. Lubrication is your friend.


I have included the files for the aluminum bed and wood bed. Choose whichever suits your needs.

Post's attachments

3mm_thread_adaptor_slop_anti-backlash - alu bed.skp 255.7 kb, 5 downloads since 2013-06-20 

3mm_thread_adaptor_slop_anti-backlash - alu bed.stl 729.15 kb, 29 downloads since 2013-06-20 

3mm_thread_adaptor_slop_anti-backlash - wood bed.stl 757.81 kb, 22 downloads since 2013-06-20 

3mm_thread_adaptor_slop_anti-backlash.skb 257.66 kb, 4 downloads since 2013-06-20 

You don't have the permssions to download the attachments of this post.
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.

39 (edited by adrian 2013-06-20 05:13:58)

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Update for you 2n2r5 ; I printed up a set last night all good.. except I had dodgy flow so I had to drill out the insert mount holes (I cheated and just used an M5 drill bit.. meh... .5 play is close enough to .6 play for the purposes I reckon given usual printer tolerances...).

However, the lip that protrudes out of the bottom plate, doesn't work on the alu platform due to its inverted threaded boss.. so I'll reprint a new bottom plate without the lipped ring tonight and then do the tedious dance to install it...

2n2r5 wrote:

Lubrication in your friend

In the interests of good taste... I'm going to leave that one right alone wink wink

40 (edited by 2n2r5 2013-06-20 05:20:47)

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

HAHAHA , that has to be one of the greatest spelling mistakes I have ever made.


Thanks adrian. I guess I should update all the aluminum bed nuts to remove that lip. It's not really necessary anyways.

BTW- I just got my DRV8825 Stepper motor drivers in. Wow, 1/32 micro-stepping is nice. So far the vertical banding is completely gone. I am hoping it stays that way. Printing off some test models now.

http://www.pololu.com/catalog/product/2133

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.

41

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

If your concerned about lubrication.....

Something I have found that works well.  Go to a motorcycle dealer and get chain lube.  It usually has a coagulant (some form of wax) that after spraying it on keeps the lube from whipping off at high speeds.  Granted our printers wont be going 96 kmh (60 mph for us heathens), yet the point is that the lube wont drip down if it is an excess.

I am an open book, write on my pages that I may learn the wisdom that you posses.

42

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

2n2r5 wrote:

BTW- I just got my DRV8825 Stepper motor drivers in. Wow, 1/32 micro-stepping is nice. So far the vertical banding is completely gone. I am hoping it stays that way. Printing off some test models now.

http://www.pololu.com/catalog/product/2133

Cool.. I'm betting that the banding is still 'there', but you've now shifted the frequency so high up the scale with the increased micro-stepping that its no longer visible. Tis also why ramping up speed makes it shift so much as well... (its quite an interesting effect actually when you do that mid-print... it could almost be exploited to create a textured wall wink ).... When you look at the banding under a scope, its amazing how consistent the globbing is.. I should post some pics of it..

43

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Downeasta wrote:

If your concerned about lubrication.....

Something I have found that works well.  Go to a motorcycle dealer and get chain lube.  It usually has a coagulant (some form of wax) that after spraying it on keeps the lube from whipping off at high speeds.  Granted our printers wont be going 96 kmh (60 mph for us heathens), yet the point is that the lube wont drip down if it is an excess.

http://www.lowes.com/pd_36389-75041-103 … facetInfo=

White lithium grease is the way to go. This one is even bio based. I won't use anything else. I would be cautious of anything that has "some form of wax". The wax could build up and inhibit movement. Our printers tolerances are tight. I don't like to do anything that might bump them a few microns if I can help it.

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.

44

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Sorry for the delay, here is my comparison pic.

If anything the banding is slightly more evident in the slop nut setup, but I'd say that's to do with the tightness of the second nut. One weakness of the design is how hard it is to adjust the nuts without disassembly, but I very much prefer how compact it is when all fitted.

Next step is to test my ballscrew I've had sitting around which has zero play.

http://www.soliforum.com/misc.php?action=pun_attachment&item=2458&download=0

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slopnutcomparison.jpg
slopnutcomparison.jpg 101.56 kb, file has never been downloaded. 

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45

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Thanks for testing it out Lawsy. I am going to try this in a few more scenarios to see if my results are a fluke. I am also going to try giving the top and bottoms of the pieces that hold the nut a light sanding to reduce friction. Ultimately, this would work best milled from aluminum or steel I think. I might fire up the CNC machine at the shop and see what I can come up with.

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.

46

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

I went crazy and fitted my ball screw last night. It was actually really easy and fast to fit.

1. Enlarge centre hole in wooden platform slightly.
2. Drill two new holes wider in wooden platform to bolt ball screw 'nut' to.
3. Grind one side of ball screw nut slightly due to it fouling on 6mm rod pulley rod at the top rear of machine.
4. Change steps per mm in firmware to 800 for z axis (4mm pitch).

The assembly is really tight and has zero lash. Unfortunately something is not quite centred at the stepper end as the rod wobbles side to side as it travels up and down, with obvious banding evident in the test print.

I think it's clear I need some sort of 'slop nut' solution for the ball screw mounting to take out the side to side wobble.

http://www.soliforum.com/misc.php?action=pun_attachment&item=2462&download=0

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ballscrewprintcomparison.jpg
ballscrewprintcomparison.jpg 70.28 kb, file has never been downloaded. 

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47 (edited by 2n2r5 2013-06-20 22:22:09)

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Do you ever sleep??!

http://www.nookindustries.com/LinearLib … wAlignment

"Linear screws should always be supported radially and axially."

Any chance a simple Pillow Block mounted at the top of the Ball Screw will help with that?

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.

48

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Not enough, I know that much.

Top support won't be an option here. The full length of the screw is already used and there isn't any room for a support bearing. I'm tempted to order a cheap 10x2mm acme leadscrew to try that.

The Replicator at work uses one and it is amazingly good in terms of lack of banding. On a 0.2mm layer height, you have to look closely to see the layer lines.

49

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Having our printers use actual dovetail ways would improve alot of the slop that is dealt with.

I am an open book, write on my pages that I may learn the wisdom that you posses.

50 (edited by adrian 2013-06-21 00:11:11)

Re: Fix z-banding w/ no backlash- "Slop Nut" (Level 2 techie - Consumer )

Hey lawsy... good to hear you gave the ballscrew a go. I suspect it will be a bit touch and go being unsupported, but as you said, you don't have the room neutral Maybe multi-start acme is worth a try.

Appreciate the effort though.. its hard to stop tinkering when its 10pm and it'll 'only take a few minutes' to install something wink wink

Downeasta wrote:

Having our printers use actual dovetail ways would improve alot of the slop that is dealt with.

You've determined this from having made how many test prints and mods to your printer and examining its construction first hand through operation?

Seriously dude... roll