1 Topic by pirvan

  • pirvan
  • pirvan
  • Member
  • Offline
  • From: San Francisco
  • Registered: 2013-03-27
  • Posts: 1,797

Topic: Geared Y Drive Replacement

I've seen a lot of attempts at dealing with the "Y" drive problems, including direct drive conversions.  Rather than derail one of the existing threads, I decide to start a new thread on a geared "Y" drive concept.

One of the "off-putting" problems wit the direct drive, at least for me, is the external motor, just hanging out on the side of the frame.  So I've been mulling the idea of the motor being still inside the frame, but instead of using a belt to drive the "Y" rod, use gears.

The problem with simple gears, is they have backlash, so to that extent, I'm using helical gears.  Due to the nature of the tooth engagement of helical gears, backlash is almost non-existent.

I'm currently at work, without access to my SD3, so I don't have any actual dimensions of the existing relations between the frame interior and the "Y" rod, and the sprocket gear for the belts, but those will be worked out later.  This is just a concept of how it would look and work.

http://www.soliforum.com/misc.php?action=pun_attachment&item=7012

Let's hear the comments smile

Post's attachments

SD3 Y rod Helical.jpg 67.69 kb, file has never been downloaded. 

You don't have the permssions to download the attachments of this post.
To print or, 3D print, that is the question...
SD3 printer w/too many mods,  Printrbot Simple Maker Ed.,  FormLabs Form 1+
AnyCubic Photon, Shining 3D EinScan-S & Atlas 3D scanners...
...and too much time on my hands.

2 Reply by redbarret

  • redbarret
  • Member
  • Offline
  • Registered: 2014-11-10
  • Posts: 520

Re: Geared Y Drive Replacement

I think this is pretty damn clever and prettier than the direct drive mods. If you'll be able to not interfere with the Y rods the gantry is on and find a decent way to secure the motor in place in such a vertical orientation,I think I'll be trying to find helical gear pulleys and doing this mod if the bearing mods don't help with the backlash.

Solidoodle 4

3 Reply by IronMan

  • IronMan
  • IronMan
  • PRINTiT
  • Offline
  • From: SC
  • Registered: 2012-09-14
  • Posts: 1,269

Re: Geared Y Drive Replacement

Like the concept...my only concern would be the ultimate wear between the gears as there is a rather thin, defined contact path between the teeth...reciprocating at times very quickly; but the right materials and the correct lube could let it last quite some time.  Also, need very solid pillow block bearing support adjacent to the horizontal rod.

And as usual, awesome CAD work, pirvan!

SD2 - Stock - Enclosure - Heated Bed - Glass Plate - Auto Fire Extinguisher
Ord Bot Hadron - RAMPS 1.4 - Bulldog XL - E3D v6 - 10" x 10" PCB Heated Build w/SSR - Glass Plate
Thanks for All of Your Help!

4 Reply by grob

  • grob
  • grob
  • Member
  • Offline
  • From: Sydney, Australia
  • Registered: 2014-01-02
  • Posts: 900

Re: Geared Y Drive Replacement

Looks pretty! Let me know if you find a source for those helicals... smile

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
Smoothieboard via Octoprint on RPi

5 Reply by Claghorn

  • Claghorn
  • Member
  • Offline
  • From: Delray Beach, FL
  • Registered: 2012-10-22
  • Posts: 730

Re: Geared Y Drive Replacement

grob wrote:

Looks pretty! Let me know if you find a source for those helicals... smile

Try this: http://us.misumi-ec.com/vona2/detail/11 … 70/?Inch=0

All you have to do is decrypt all the acronyms and jargon in their configuration selection :-).

Claghorn's Website

6 Reply by slimstar2

  • slimstar2
  • slimstar2
  • Member
  • Offline
  • From: North Providence Rhode Island
  • Registered: 2014-03-28
  • Posts: 144

Re: Geared Y Drive Replacement

Cool idea  hope it works out

SD3, RAMPS 1.4, Lawsy's carriages modified by me, 2 SSRs, E3D V6, 2 Power supplies, Independent monitoring of both power supplies (amps and volts) also extruder and bed temps, Blue Tooth connectivity, bearings in all axis & rotational points, Y axis direct drive.  Remotely controlled power box on / off . Gecko Tec build plate . Renamed FrankenDoodle

7 Reply by pirvan (edited by pirvan 2014-12-09 23:53:50)

  • pirvan
  • pirvan
  • Member
  • Offline
  • From: San Francisco
  • Registered: 2013-03-27
  • Posts: 1,797

Re: Geared Y Drive Replacement

Claghorn wrote:
grob wrote:

Looks pretty! Let me know if you find a source for those helicals... smile

Try this: http://us.misumi-ec.com/vona2/detail/11 … 70/?Inch=0

All you have to do is decrypt all the acronyms and jargon in their configuration selection :-).

Those are too big.

What we're looking for is a helical gear with a 20° angle of pressure, 45° helix angle, 0.5 module, 18 teeth.  The bore diameter is 5 or 6mm, the hub is ~8mm and is drilled & tapped for a grub screw.  The face width is ~8-10mm, and the overall diameter should be about 13.75mm. If we find something with less teeth (16 for example), the diameter will go down to <12mm.

The reason I gave approximate numbers for some of the dimensions, is because most helical gears are custom made, however we should be able to find something close.

The module will ultimately determine the tooth size and pitch, and thus control the overall diameter.  The smaller the module, the smaller/finer the teeth and the more of them you can have on a given diameter.

The gears we're looking for are usually referred to as Miniature, or hobby gears.  They can be found at hobby shops, they're used in clock making, RC cars and helicopters, etc.  The materials are either steel, brass, nylon or even cheap pot metal.

If I were to have a choice, I'd probably get brass.  It has a natural lubrication, and believe it or not outlasts steel, in all but the harshest environments.

To print or, 3D print, that is the question...
SD3 printer w/too many mods,  Printrbot Simple Maker Ed.,  FormLabs Form 1+
AnyCubic Photon, Shining 3D EinScan-S & Atlas 3D scanners...
...and too much time on my hands.

8 Reply by grob

  • grob
  • grob
  • Member
  • Offline
  • From: Sydney, Australia
  • Registered: 2014-01-02
  • Posts: 900

Re: Geared Y Drive Replacement

pirvan wrote:

Helical gear with a 20° angle of pressure, 45° helix angle, 0.5 module, 18 teeth.  The bore diameter is 5 or 6mm, the hub is ~8mm and is drilled & tapped for a grub screw.  The face width is ~8-10mm.

I'd just forward that to someone on Alibaba and see if they'll make you a couple of samples... smile

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
Smoothieboard via Octoprint on RPi

9 Reply by pirvan

  • pirvan
  • pirvan
  • Member
  • Offline
  • From: San Francisco
  • Registered: 2013-03-27
  • Posts: 1,797

Re: Geared Y Drive Replacement

We could always try to print them wink

http://www.soliforum.com/misc.php?action=pun_attachment&amp;item=7020

Post's attachments

gears.jpg
gears.jpg 39.78 kb, file has never been downloaded. 

You don't have the permssions to download the attachments of this post.
To print or, 3D print, that is the question...
SD3 printer w/too many mods,  Printrbot Simple Maker Ed.,  FormLabs Form 1+
AnyCubic Photon, Shining 3D EinScan-S & Atlas 3D scanners...
...and too much time on my hands.

10 Reply by mdrVB6

  • mdrVB6
  • Member
  • Offline
  • Registered: 2013-12-18
  • Posts: 717

Re: Geared Y Drive Replacement

Would your Y motor be in conflict with the Y end stop in this position?  Of course, there are multiple ways to get around this.

Just a thought- if you didn't mind cutting a hole in the back of the case, could you use something like the wade extruder gears that are two different sizes instead of helical gears?  I think this would let you get more torque, at the possible expense of backlash if they are not very well aligned.  Of course, your best bet is to clean and lube your rods to have as little friction as possible, but there are still people who have had issues with skipping.

Personally, I'm in the process of gathering parts to do a direct drive conversion since I don't mind having the motor outside the case.

SD4 w/ RUMBA, E3D Volcano, all bearings, glass bed

11 Reply by pirvan

  • pirvan
  • pirvan
  • Member
  • Offline
  • From: San Francisco
  • Registered: 2013-03-27
  • Posts: 1,797

Re: Geared Y Drive Replacement

Last night I took a few measurements of my SD3.  Here are the results.

http://www.soliforum.com/misc.php?action=pun_attachment&amp;item=7030

So I'm thinking that the best anchoring solution would be "L" brackets to the back face both to the front and the back of the motor.

Post's attachments

Geared Y Drive dimensions.jpg
Geared Y Drive dimensions.jpg 88.44 kb, file has never been downloaded. 

You don't have the permssions to download the attachments of this post.
To print or, 3D print, that is the question...
SD3 printer w/too many mods,  Printrbot Simple Maker Ed.,  FormLabs Form 1+
AnyCubic Photon, Shining 3D EinScan-S & Atlas 3D scanners...
...and too much time on my hands.

12 Reply by grob

  • grob
  • grob
  • Member
  • Offline
  • From: Sydney, Australia
  • Registered: 2014-01-02
  • Posts: 900

Re: Geared Y Drive Replacement

If you've got a pillow block bearing on the back of the case for the shaft just to the right of the motor I reckon bolting it to the back will be fine - keeping the shaft and the motor fixed relative to one another on the (potentially) flexible back wall...

You will want a little bit of adjustment of the motor forward and back to get the mesh right, the motor shaft and driveshaft will need to be quite accurately orthogonal (so alignment of L brackets needs to be good/adjustable), but as it's helical left/right is pretty tolerant. Looking good. smile

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
Smoothieboard via Octoprint on RPi

13 Reply by pirvan

  • pirvan
  • pirvan
  • Member
  • Offline
  • From: San Francisco
  • Registered: 2013-03-27
  • Posts: 1,797

Re: Geared Y Drive Replacement

Ultimately, it's a fairly simple bracket design.  It could be made from some steel angle you could buy at a hardware store, drill and mount or you could print one like the one I did.

http://www.soliforum.com/misc.php?action=pun_attachment&amp;item=7062

Now, if we could only find the right helical gears.... BTW, any response from the AliBaba vendor ?

Post's attachments

Geared Drive concept 2.jpg 42.99 kb, file has never been downloaded. 

You don't have the permssions to download the attachments of this post.
To print or, 3D print, that is the question...
SD3 printer w/too many mods,  Printrbot Simple Maker Ed.,  FormLabs Form 1+
AnyCubic Photon, Shining 3D EinScan-S & Atlas 3D scanners...
...and too much time on my hands.