3 Z axis Assembly which one So i have these 3 Z designs to choose from unless someone else has something better. No cantilever designs as this is going to be 400X400 heavy bed assembly. I have had reviews that the 3 leads and 3 rods is over constrained but not on the 2 leads and 4 rods which i dont understand as i have 6 points of contact with each. The rods will be have solid steel mounts. We can talk about lead mounts. I want to hang the leads as it seems s much better to hang the bed then push it. With the 3X3 bed assembly i cant hang the bed as the belts would inhibit the ease of filament to the X carriage so i put the leads on the bottom, or i threw up a few more pulleys and longer bed to make it a square. I feel i need to motors as the weight of the bed would be to much for one. the only problem im having with 2 seperate motors is keeping them sinked, but will this be much of and issue? i do plan on running the through a belt to drive each lead as seen in the 2X4 setup. I wnt to hear what you think of the designs spacing, mounting driving etc. i want to start building but am having an issue getting this Z thing figured out. i would like to go linear guides but dont see the funds to do so unless i go cheap shitty china. https://reprap.org/forum/read.php?397,821577,821577#msg-821577 Fri, 16 Oct 2026 02:08:54 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?397,821577,832519#msg-832519 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,832519#msg-832519
Quote
MKSA
Real units like here: ?
[www.youtube.com]

That video is gold. Standard was OK for building my house, but anything small and mechanical design greatly benefits from millimeters, like printer parts!]]> gmedlicott CoreXY Machines Fri, 31 Aug 2018 13:30:47 -0400 https://reprap.org/forum/read.php?397,821577,832518#msg-832518 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,832518#msg-832518
So your option 2 is the likely most efficient. You can run all three lead screws off one motor, just make sure it is a decent size Nema 17. The lead screws act as gear reduction, so even with 4-turn lead screws and a heavy bead (I have basalt tile on mine), one motor can work. If your bed is really heavy or the motor is struggling, you could switch to 1-turn lead screws for 4x more torque.]]> gmedlicott CoreXY Machines Fri, 31 Aug 2018 13:29:47 -0400 https://reprap.org/forum/read.php?397,821577,830979#msg-830979 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,830979#msg-830979
Quote
bbcbggr54
So i have these 3 Z designs to choose from unless someone else has something better.
I believe that the simplest design you may choose will be 3 motors Z. Belts look nice but they add an additional constraint to the design - belt length. Since it is closed loop belt redesigning your printer for a different size will be challenging. In 2 years your belt will wear out and boom nobody makes belts of that length anymore (kidding). Or just look how complicated your design already is, and how much it will be simplified if 3 motors will replace all that structure around the belt. You also adding vertical height to your printer when using the belt, cause the belt needs to run under the bed in the lowest bed position. It is not a lot but still something you add.
But I know that you are already convinced that belt design is the best. So for picking the design you like first find the belt of appropriate length - because this is what you will design around.]]> piper3d CoreXY Machines Sun, 12 Aug 2018 02:36:59 -0400 https://reprap.org/forum/read.php?397,821577,830717#msg-830717 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,830717#msg-830717
Quote
Leafy1
I assumed it was relevant since it was on the first page. I guess I should have liked for the date. And yes, real units, it's what we use when we make real parts in actual industry. And I'd like you to tell me how much you weigh in Newtons without having to calculate it.

Real units like here: ?
[www.youtube.com]]]> MKSA CoreXY Machines Thu, 09 Aug 2018 11:36:55 -0400 https://reprap.org/forum/read.php?397,821577,830703#msg-830703 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,830703#msg-830703 Leafy1 CoreXY Machines Thu, 09 Aug 2018 09:40:42 -0400 https://reprap.org/forum/read.php?397,821577,830702#msg-830702 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,830702#msg-830702
Quote
Leafy1
Do a cantilever. The hgr15 rail will take 100 N-m of moment in that direction. In real units thats like 45 pounds at the far edge of your build plate. You step up to the hgr30 rail and you could use your build plate as a seat.


Real units ??? Amusing. We are in the 21° century you know. In fact 9 Aug 2018 so how about working in REAL TIME, you answer to discussions that have been dead for months and where even stillborn :)

[www.youtube.com]]]> MKSA CoreXY Machines Thu, 09 Aug 2018 09:15:25 -0400 https://reprap.org/forum/read.php?397,821577,830691#msg-830691 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,830691#msg-830691 Leafy1 CoreXY Machines Thu, 09 Aug 2018 08:32:38 -0400 https://reprap.org/forum/read.php?397,821577,821751#msg-821751 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821751#msg-821751
As far as lifting goes, you can make a cantilevered bed, lifted with one screw, but the free end will tend to bounce. Lifting with two screws at the middle of opposite sides of the bed reduces the bounce problem, but it is still cantilevered- just half the length. Lifting with 3 screws provides a stable platform for lifting, like a 3 legged table or stool- it won't wobble like a 4 legged table/stool.

Two screws alongside guide rails (rails and screws should be kept close together) on the right and left sides near the front of the printer (providing easy access to the print from the front of the printer), with a third screw (with no third guide rail), which keeps that cantilevered end of the bed from bouncing, at the center of the back of the printer is just about ideal.

If the frame is built solidly, the bed plate is on a stable support and leveling structure, and the Z axis screws are driven by a single motor, you will level the bed once and will not have to relevel it.

You'll see a lot of variations. It isn't impossible to get a system with 6 guide rails and 5 screws to work, but the more you do beyond basic constraint the harder it is to make it work (and the cost goes up).]]> the_digital_dentist CoreXY Machines Wed, 09 May 2018 23:13:30 -0400 https://reprap.org/forum/read.php?397,821577,821749#msg-821749 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821749#msg-821749 bbcbggr54 CoreXY Machines Wed, 09 May 2018 22:19:23 -0400 https://reprap.org/forum/read.php?397,821577,821678#msg-821678 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821678#msg-821678
Quote
bbcbggr54
no excuses is right they are the best i can think of or seen. which designs are better i havnt seen them? this build is up for discussion not just negatuve remarks i am a rookie.

See here, in a thread you initiated: [forums.reprap.org]]]> MKSA CoreXY Machines Wed, 09 May 2018 01:30:55 -0400 https://reprap.org/forum/read.php?397,821577,821669#msg-821669 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821669#msg-821669 bbcbggr54 CoreXY Machines Tue, 08 May 2018 22:35:24 -0400 https://reprap.org/forum/read.php?397,821577,821668#msg-821668 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821668#msg-821668 bbcbggr54 CoreXY Machines Tue, 08 May 2018 22:32:21 -0400 https://reprap.org/forum/read.php?397,821577,821644#msg-821644 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821644#msg-821644 No excuse to come with such non sense when you have good designs presented here.]]> MKSA CoreXY Machines Tue, 08 May 2018 15:05:54 -0400 https://reprap.org/forum/read.php?397,821577,821603#msg-821603 Re: 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821603#msg-821603 whosrdaddy CoreXY Machines Tue, 08 May 2018 03:15:19 -0400 https://reprap.org/forum/read.php?397,821577,821577#msg-821577 3 Z axis Assembly which one https://reprap.org/forum/read.php?397,821577,821577#msg-821577 bbcbggr54 CoreXY Machines Mon, 07 May 2018 17:17:42 -0400