Notifications
Clear all

Issues I had with MK2 build  

  RSS
Keri
 Keri
(@keri)
Member
Issues I had with MK2 build

Hi!
I received my MK2 on Thursday and spent about 10 hours building it over the last few days. I just wanted to mention some issues I had so that if someone else experiences them they won't feel alone!

Many of the printed parts are not as precise as I'd like them to be. Placing the nuts into the printed parts, specifically the ones which need to be dropped in, can be difficult.

The X stop did not hit the carriage. I tried to screw the stop as close to the edge as possible with the included screws. I ended up unscrewing it, pushing it out and using duct tape. I could drill new holes but I will try to glue or tape something to the carriage instead.

When I was tightening the screws on the Y axis stage I slipped and broke off the piece that holds the y axis stop. I was able to use acetone to fix the piece.

The zipties which hold the bearings to the y carriage need to be TIGHT! I had them mostly tight but after I assembled everything else it was loose so I had to take it apart and put new ties on and tighten them extra.

I wish it was easier to tighten the belts. It took me awhile to get the right PING. Even now I think they are still a bit loose.

Inserting the LM8UU linear bearing into the X Axis was very difficult. I ended up using a hammer .

What is the 3mm filament for? Was that just to give the wires more structure?

Did anyone else notice the resemblance of the y carriage to a face? It was strange to put screws in the eyes and zipties up its nose!

I am having a lot of trouble leveling it and calibrating it. I think my z axis is off so I'm playing around with it.

Lastly it would have been great to have a few extra screws and nuts. I lost one somehow and here in the US its hard to find metric parts. I went to Lowes and they had M3 16 and M3 20 but not M3 18 like I needed.

Other than that the build wasn't too bad. 🙂

Posted : 30/05/2016 6:43 pm
Jarred
(@jarred)
Eminent Member
Re: Issues I had with MK2 build

Future tip, you can get the screw that's a little bit longer. Just put two or three nuts on it and put them about halfway down the screw. Now you can drag the bottom of the scre on sandpaper to shorten it. Once the desired length is achieved you remove the nuts which should take care of any burrs. Had to do this a couple of times when hardware stores didn't have the right size screw for RC helicopters

Posted : 30/05/2016 6:57 pm
joey.h
(@joey-h)
Active Member
Re: Issues I had with MK2 build

Another tip for tight nut holders. Put one on a long screw, heat it up with a lighter and then put it in place. Surrounding plastic will melt perfectly into place. Better fit is not possible 😀

Posted : 30/05/2016 7:49 pm
VortyZA
(@vortyza)
Eminent Member
Re: Issues I had with MK2 build

All in all I found it to be a fantastic kit.
I have built 3 printers so far and this was by far the easiest kit to put together!

I found I could use a longer screw to pull the nuts into place. I found that most of the printing was exceptionally good - the filament stand print quality was astoundingly good - I could not see the layers at all!

Problems I experienced were:
I wasn't sure what smooth rods to use for the Y-axis, the build manual didn't specify. I guessed the middle sized rods because of the length of the threaded rods and was fortunately correct. Later on I saw that the other axis steps tell you "The shortest rods" or "The longest rods".

The belts really are frustrating to get tight enough to ping. The under carriage was a particular problem because it was not printed solid and when I was trying to slip the belt loop over the pegs the tension snapped the peg off. I had to insert a screw through the peg to a nut behind it to repair the damage.

The other Prusa clone kit that I put together had a tensioning system on the belts where the idlers have 2 parts - one with the wheel to hold the belt which is attached to the other part which is attached to the frame via a screw and nut system, so the screw could be tightened pulling the idler towards the frame causing the belt to tighten up nicely.

I managed to jam the filament after my first print (my fault), but to clear the jam was incredibly difficult. I ended up having to remove the entire front of the hot end construction and separate the E3D to get to the jammed plastic. Hopefully I don't make a habit of that - it was a pain!

Some further thoughts / Wishlist:
I'd like a neater way of attaching the LCD on the front of the printer - It would be possible to make paths for the zip ties to run through the plastic standoffs around the threaded rods to keep them mostly out of sight.

It would be great to see the electronics updated at some point - the Ormerod has an updated processing board which includes onboard Ethernet and a web interface. It makes the device so easy to use, fast to upload models and provides many diagnostic capabilities.

Posted : 31/05/2016 9:29 am
Patrik Rosén
(@patrik-rosen)
Reputable Member
Re: Issues I had with MK2 build

Great posts guys!

I'm getting my MK2 in a week or two, this is great headsup for the assembly.

Me on 3dhubs!
Posted : 31/05/2016 11:39 am
Josef Průša
(@josef-prusa)
Member Admin
Re: Issues I had with MK2 build

Hi!
I received my MK2 on Thursday and spent about 10 hours building it over the last few days. I just wanted to mention some issues I had so that if someone else experiences them they won't feel alone!

Many of the printed parts are not as precise as I'd like them to be. Placing the nuts into the printed parts, specifically the ones which need to be dropped in, can be difficult.

Hi Keri, thanks for the feedback! We really appreciate it. The parts from first few days of production were not upto the standard we ship out normally. I took care of that when I got back from San Francisco. If you need any replacement, just let me know, we will ship it out for free.

The X stop did not hit the carriage. I tried to screw the stop as close to the edge as possible with the included screws. I ended up unscrewing it, pushing it out and using duct tape. I could drill new holes but I will try to glue or tape something to the carriage instead.

We will adjust the position of the screws or make the trigger on the carriage bit longer.

The zipties which hold the bearings to the y carriage need to be TIGHT! I had them mostly tight but after I assembled everything else it was loose so I had to take it apart and put new ties on and tighten them extra.

Inserting the LM8UU linear bearing into the X Axis was very difficult. I ended up using a hammer .

This is fixed as I mentioned earlier.

What is the 3mm filament for? Was that just to give the wires more structure?

Yes.

Did anyone else notice the resemblance of the y carriage to a face? It was strange to put screws in the eyes and zipties up its nose!

😯 😀

I am having a lot of trouble leveling it and calibrating it. I think my z axis is off so I'm playing around with it.

Is the probe aligned with the points?

Founder and owner / Majitel a zakladatel
Posted : 31/05/2016 12:52 pm
Keri
 Keri
(@keri)
Member
Topic starter answered:
Re: Issues I had with MK2 build

keri.h wrote:
I am having a lot of trouble leveling it and calibrating it. I think my z axis is off so I'm playing around with it.

Is the probe aligned with the points?

It is CLOSE but not exactly aligned with the points. Maybe this is due to the fact that the X endstop is a little off. Are the points actually pressure points or something for the self-leveling?

I just tried to calibrate Z and it went out of whack. https://drive.google.com/file/d/0B7_KoKdC_vxbc1R1akxBV3plQ28/view?usp=sharing Then i decided to test it by printing the circle calibration and the nozzle was so far off that it dug a crevice in the bed! This whole thing probably has a simple fix that I haven't' found yet.

I am relatively new to 3D printing. This is my first 3D printer build. I had a Monoprice Maker Select 3D, but decided to upgrade to this one. I made three successful prints (and about 6 failed prints) and I am amazed at the quality of the print, the speed and the quietness of the machine! I am very excited to work out the kinks and get the printer going!

Posted : 31/05/2016 5:27 pm
richard.l
(@richard-l)
Member Moderator
Re: Issues I had with MK2 build

Keri,

Just from looking at the video it would seem your z-probe may be a little too high causing the nozzle to come in contact with the bed.

Posted : 01/06/2016 4:33 pm
pbnj
 pbnj
(@pbnj)
Trusted Member
Re: Issues I had with MK2 build

Mine kit came on Friday the 28th I started about 1:30 putting it together;
Problems:
1. Which rods go where after reading the entire instructions figured that out. Maybe color coding the ends would help. At least call it out in the beginning:
2. Need more tools than are supplied.
a. Very small soft face hammer
b. Long allen drivers
c. Small side cutters.
d. Wrench to fit the bed leveling sensor.
e. Tie wrap gun to tension and cut the many tie wraps.
3. I would have been very nice to have extra screws and nuts, must have spent over an hour hunting the ones I dropped.
4. X rod supports too tight had to force them in with soft face hammer causing the brackets to split. Cure: Super glue the cracks.
5. X carriage does not hit the limit switch. Cure: superglue and a small piece of tie wrap glued to carriage.

By 7:30 I had all the machine assemble less electrical. It was time quit for the day and pick up on Saturday. I had to work.
Back on project about 10 am finished the electrical mounting and hook up by 11. Ran the check out and everthing was fine.
Calibration problems:
1. The 1000 mm that the manual said to set the frame is just a guess they could have figured it out. Had to adjust both sides to get them to match up with the sensors in the heated bed.
2. After a number of runs I finally gat every thing set to find out that my right motor was not moving all the time. A couple of exchanges with online help and Josef figured out that we need to take it out of silence mode. Who know that there was a silent mode. Everything ran great. 2 pm and we have a family thing to do, no prints for me today.

Sunday; finally going to get to print some stuff. Started out with a couple of bottle openers with Slic3r made those then took the them to simply3d that normally produces very fine prints. I think the Slic3r made better prints. When the Parts Stl were posted I started making them. Some where after 5 hours of printing the extruder filament drive gear came loose and it did not finish.

Monday, back with tech support about the drive gear, not much help. I thought the allen head set screw was stripped, it turn out to be the allen wrench supplied is just a little to small. When to the tool box and tighted it with one that fit. Finished making my spare parts.

Tuesday, ran real parts on them with simply3d as the slicer. Used the setup from Josef this was a 12 hour print. Outside look pretty good, however when we cut it apart and there is some tweeking that needs to be done. Pretty impressed with the machine for under $1000. So I order one for work.

Next we go on to PET and Nylon.

Posted : 01/06/2016 10:31 pm
marco.t
(@marco-t)
New Member
Re: Issues I had with MK2 build

Thought I could share my ten cents on this topic.

Got my kit last friday and spent the weekend for building and calibrating it. The overall feeling I got from the kit was very positive - the way how the parts were organised into separate bags and how they were labeled, made building very easy. The printed assembly manual along with the online version with high resolution pictures made almost no room for mistakes (if you first read a few steps ahead what you're going to do next). Most of the printed parts had a quite good quality.

The problems I had...
- The extruder motor pulley didn't fit into it's place without some knife work. The "cone" below the pulley where the white tube from the nozzle pops out, was too high. But it was quite easy to carve out some extra material with a knife.
- Mounting the rambo cover base took some time as it was quite difficult to see what you're doing when the box is full of hands. Having a nut in the cover and screws coming from the other side of the frame could be much easier but understand that it doesn't look so good.
- The biggest problem though was the XYZ-calibration. It always stopped during the first round of calibration where it tries to find the four calibration points. After the fourth point it just stopped with error message "XYZ calibration failed, please consult the manual". So I followed all the steps instructed in step 1 - adjusted the PINDA probe, checked that everything is aligned in the frame correctly and pulleys do not slip. One the concerns was the set of wires coming out the of extruder that they are slightly touching the rambo box when the extruder is moved to it's leftmost position but during the calibration I didn't notice that the wires were touching the box. But after spending several hours with trying different things, I did the calibration so that when the extruder was doing something on the left side, I manually bent the wires to the right. This way the calibration passed with the result "XYZ calibration ok, X/Y access are perpendicular". Afterwards, e.g. the calibration done before the printing, I didn't have these kind of problems any more.

So altogether quite minor problems and enjoyed the whole building process. There wasn't even a single moment where I could think of throwing the darn thing out of the window.

Posted : 31/10/2016 8:45 am
Share: