Welcome! Log In Create A New Profile

Advanced

My Prusa MGN

Posted by bme 
bme
My Prusa MGN
May 14, 2016 07:04AM
Hi people!

I am still working on my printer I call Prusa MGN. STL files will be available for download in a couple of months.

Video:
[www.youtube.com]





Some prints in ABS and PLA:

Re: My Prusa MGN
May 14, 2016 01:17PM
Looks nice. What's the cost for the set of linear rails?
bme
Re: My Prusa MGN
May 14, 2016 04:50PM
Thanks!
About 22$ piece inclusive shipping.
Re: My Prusa MGN
May 14, 2016 07:43PM
Quote
bme
About 22$ piece inclusive shipping.

That seems very reasonable, got a link? smiling smiley
bme
Re: My Prusa MGN
May 15, 2016 02:51AM
Search "MGN12" on AliExpress.com
Re: My Prusa MGN
May 15, 2016 08:58AM
nice im building a kossel and i have a prusa i3 i like that idea that may make me decided not to decommission it once the kossel built


Check my rubbish blog for my prusa i3

up and running
[3dimetech.blogspot.co.uk]
Re: My Prusa MGN
May 16, 2016 10:32AM
The print looks pretty good. What do you think about the motion on the mgn rails? Are they smooth and free of play? I've been using used Japanese rails but if the Chinese rails are OK I may switch. I had previously seen some comments about them being not so good.


Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
Re: My Prusa MGN
May 16, 2016 02:20PM
Quote
the_digital_dentist
The print looks pretty good. What do you think about the motion on the mgn rails? Are they smooth and free of play? I've been using used Japanese rails but if the Chinese rails are OK I may switch. I had previously seen some comments about them being not so good.

I have also ordered three mgn12 rails in china. They arrived last week. They didn't run as smooth as i had hoped, sprayed them with wd40, run them a few times up and down with my hand then wiped the rails with some cloth and now they run fantastic.

Edit: there is hardly any play..

Edited 1 time(s). Last edit at 05/16/2016 02:22PM by gforce1.
Re: My Prusa MGN
May 16, 2016 03:39PM
wd40 isnt a lubricant its a degreaser


Check my rubbish blog for my prusa i3

up and running
[3dimetech.blogspot.co.uk]
Re: My Prusa MGN
May 16, 2016 03:40PM
Hardly any or none? There should be none.


Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
bme
Re: My Prusa MGN
May 16, 2016 04:30PM
I have more then ten peaces. Two of them were not so smooth. I removed some balls and placed them back. It solved my problem.
You can replace carriages from one rail to another.

Moving carriages in all direction I don't feel any play.
Re: My Prusa MGN
May 17, 2016 12:49AM
@DD
I dont feel any play by hand.

Edited 1 time(s). Last edit at 05/17/2016 12:57AM by gforce1.
Re: My Prusa MGN
May 17, 2016 06:42AM
Quote
chris33
wd40 isnt a lubricant its a degreaser

True, but a lot of Chinese parts come with protective grease for transport and storage, and wd40 would likely work quite well for removing that. The question then becomes what to use for a normal lubricant.
Re: My Prusa MGN
May 18, 2016 02:38AM
Quote
JamesK
The question then becomes what to use for a normal lubricant.

I bought some STAF rails from a Chinese seller and asked her what grease she recommended. She said 'anti-rust oil'. Nothing complicated. A friend will give me some Vactra #2 way oil which I will try.

P.S. I bought a cheap set of HIWIN clones and will use them for my first machine and save the STAF for the second machine with the kinks worked out. I cleaned the cheapies with WD40 because I thought it would work well for that purpose and it seemed to do the job. The clones seem passable but the STAF are sweet quality.


New browser from the creator of Opera: [vivaldi.com]
Re: My Prusa MGN
May 18, 2016 06:17AM
That is a very important question. Do we need to grease them? I've bought rails from a local manufacturer (they probably manufacture it in China tough). There is no play whatsoever and the movement is quite smooth but it feels like I am moving a bearing on a rod, you can feel the same amount of friction, which isn't really surprising as there are small balls in both of them and they are against some kind of metal, so some friction is probably expected. Using grease is not always recommended for bearings, as dust can accumulate inside, I wonder if it is true for rails.
Re: My Prusa MGN
May 18, 2016 03:49PM
@bme I like your machine. I've watched many of your previous video's. You seem to get some very consistent layer alignment - nice! I watched your video when you ran your machine FAST. Obviously the Y carriage is the heaviest but it doesn't seem to have you from pushing the machine pretty hard. Have you got a total weight for the Y carriage?


New browser from the creator of Opera: [vivaldi.com]
Re: My Prusa MGN
May 18, 2016 03:55PM
I know I certainly will oil mine. The wipers on the HIWIN clones are very imprecise so they won't stop junk from getting in but I will oil them anyway. There will be friction and I'm sure oil will help. The STAF rails have very nice wipers and would stop dirt from getting in. Regarding grease: my first printer was an Up! and it used a lithium grease on the rails.


New browser from the creator of Opera: [vivaldi.com]
bme
Re: My Prusa MGN
May 19, 2016 02:29AM
I will tell you the weight of carriage when I am at home on Sunday.
Re: My Prusa MGN
May 19, 2016 02:53AM
Quote
bme
I will tell you the weight of carriage when I am at home on Sunday.

Thank you. All the best ..


New browser from the creator of Opera: [vivaldi.com]
bme
Re: My Prusa MGN
May 22, 2016 04:01AM
Everything on the Image is 178 grams. The weight will be around 200 grams when finished.
The weight of MGN12 carriage is 52 g.



Edited 1 time(s). Last edit at 05/22/2016 04:29AM by bme.
Re: My Prusa MGN
May 22, 2016 03:32PM
Quote
bme
Everything on the Image is 178 grams. The weight will be around 200 grams when finished.
The weight of MGN12 carriage is 52 g.


Thank you for weighing the material and posting this picture. It's pretty light. Less than a NEMA17 stepper. I'm wondering how much the two Y plates weigh? The build surface plate and the spreader that attaches the blocks to the rail. I'm guessing this is pretty heavy? But the steppers seems to have no problem moving it fast. So I'm impressed.


New browser from the creator of Opera: [vivaldi.com]
bme
Re: My Prusa MGN
May 22, 2016 04:02PM
Hi and thanks!

Aluminium heat bed plate = 270 g.
Aluminium plate = printing on it = 220 g.
Re: My Prusa MGN
May 22, 2016 09:43PM
Quote
bme
Hi and thanks!

Aluminium heat bed plate = 270 g.
Aluminium plate = printing on it = 220 g.

Cool. Not too heavy. Well, I'm looking forward to more videos of your machine in operation and pictures of print quality if you take any. Thanks for sharing your machine.


New browser from the creator of Opera: [vivaldi.com]
bme
Re: My Prusa MGN
May 23, 2016 01:53AM
The last two prints:


bme
Re: My Prusa MGN
May 23, 2016 02:11PM
I try to print this file:
It looks a little complicated. An Image is coming when finished.
Video:
[www.youtube.com]






Edited 2 time(s). Last edit at 05/23/2016 03:37PM by bme.
Attachments:
open | download - heh.stl (92.7 KB)
Re: My Prusa MGN
May 23, 2016 08:40PM
Hey BME I've been watching your videos for a long time. Really nice work. smiling smiley

I have a question though, I saw your image here: [www.onel.se]

See how you have ripple (I'm not sure what to call it) on the sides of the holes? Have you had any luck in reducing it or know the cause? Is it vibration on Y? I'm having the same problem... Hmmmmm.
bme
Re: My Prusa MGN
May 24, 2016 01:57AM
My printer is not yet finished.

You probably mean "ghosting". You can reduce this by decreasing your acceleration and speed and probably a mass of your printer.

I am waiting for some part to arrive. Maybe this one can help to reduce ghosting too( see the image). When I use just ball-bearing then I don't like to put belts teeth directly on ball-bearing.
I usually cut the belt and put the flat side on ball-bearing.

synchronous wheel pulley

Re: My Prusa MGN
May 24, 2016 02:51AM
Thanks! Yeah I'll buy a couple of those too I think. It's an annoying problem.
bme
Re: My Prusa MGN
May 24, 2016 12:36PM
This image show you how I mount a belt on a ball bearing. You need two belts on X axis for example.


bme
Re: My Prusa MGN
May 24, 2016 03:25PM
I have now installed missing synchronous wheel pulley on Y axis.
I print this file which is 6 x 6 x 3 cm.
I'll show the result when printing is finished.



Edited 2 time(s). Last edit at 05/24/2016 04:56PM by bme.
Attachments:
open | download - cb.stl (16.1 KB)
Sorry, only registered users may post in this forum.

Click here to login