Q&A W/ Rostock Max, Mendel 90, Kossel and Ultimaker Original+

[gabriela3d]

Day 3 of our community talks with the 3D Printer Guide finalists in the KIT/ DIY category focuses on the Rostock Max, Mendel 90, Kossel and Ultimaker Original+ models.

If you have any questions for the manufacturers, other owners or if there’s anything you want to share with us that we haven’t addressed in the guide, then leave a comment below.

Let’s Talk!

[gabriela3d]

Hey @artexmg @Oscar_10 @Brandon_4 @Christopher_1 @Jim_12 @cester @Nakcam @Lukelektro @Umake @James_2 @Ikki @Patola @elmuchacho @CopabX any thoughts on this?

[James_2]

@gabriela3d - curious how the UMO printer had a con of “running cost” - you put filament in and get a model out so the only consumable is filament - same as all the other printers, except you don’t have to use a raft or brim, or skirt …

I guess we all tend to get to know our own printers best - but so far I have found the UMO fairly bullet proof - recently had a failure of the bowden at the feeder end - and just took the thing apart and swapped the wood pieces around - problem fixed!

It is a tinkerer’s machine, but I use it professionally and to print for others and it is a real worker!

James

[elmuchacho]

IMHO If you require a machine to print accurate dimension, delta like the Kossel are the most challenging to calibrate. The smallest error in tower twisting, printed part or rod length and you will have trouble printing accurately sized object at different size. But if accuracy is a secondary requirement they actually print faster than my cartesian with a much better surface finish and this is great when you need them to print a most decors like objects. The Kossel is definitely worth considering when selecting a printer for the simple and good reason of the massive 23cm build height it offer for such a small footprint on your desk.

[gabriela3d]

Well ‘bullet proof’ basically says it all Thanks for sharing this with us, James! I’m sure that many UMO owners agree withy you.

[gabriela3d]

As the guide showed, Kossel is a favourite with many - functional and cost effective. Thanks for sharing, elmuchacho!

[CopabX]

Of my 4 printers (expecting a 5th child soon) I’d have to rate the Kossel as my favorite because of print speed and because it looks so damn cool. There isn’t a huge time advantage on small parts < 1 hour because of acceleration (you can’t hit 100mph backing out of your driveway). However on large parts I’ve seen the advantage to be up to 2 hours faster than my Ultimaker Original. The additional speed also allows it to overcome the retraction problem that plagues many bowden type printers.

I agree with @elmuchacho that delta-style printers are very difficult to calibrate, but once calibrated the Kossel is fairly bulletproof if you didn’t cheap out on parts. I carried mine from NJ on a bus, subway, and 5 blocks of walking and didn’t have to change my settings afterwards.

From my personal experience, I’ve always had trouble with the Ultimaker bowden setup, but since I built my own that might be a moot point with the real kits. However, the cantilever bed is notoriously inconsistent and your initial z might change throughout the day as the bed heats up (if you used plastic parts that is). On a plus side, the enclosed frame makes it very easy to convert it to a heated chamber which makes it my only truly ABS capable printer.

From what I can see, the Mendel90 is similar to the Prusa i3 in terms of structure so I’ll comment on my i3 experiences. My i3 is the most accurate of the bunch but also the most delicate. To really get good prints with a printer built from threaded rods, I had to bolt the frame to a piece of plywood. Once I did that, I could calibrate it without having to worry about losing settings if I moved it from my dining room to my living room. Now it prints within 0.04mm accuracy.

So just a quick summary for each (feel free to comment if you disagree)

Kossel (0.2mm accuracy)

Pros:

- Print speed

- Can be modified to be a pick and place machine

- Durable frame

Cons:

- Cannot handle large prints (XY)

- Difficult to calibrate for beginners, but definitely possible

- Hard to convert to a heated chamber

Ulitmaker Original: (0.1mm accuracy)

Pros:

- Enclosed frame --> heated chamber --> ABS

- Laser cutter friendly build

Cons:

- Cantilever bed prone to warping/bouncing

- Bowden?

- For some reason, I cannot get quality fast prints so it set significantly slower than the Kossel

Prusa i3: (0.04mm accuracy)

Pros:

- Easy to calibrate all parts

- Dimensionally accurate parts

- Direct extruder --> superior retraction and easy filament changes

Cons:

- Threaded rod frame weak, requires modifications

[Jim_12]

I can’t really agree with @CopabX that the Mendel90 is equal to the Prusa I3 in terms of structure. The Mendel90 does not use rods for it’s frame only for the z-axis. Second improvement over the Prusa is the use of flat cables avoiding the chaotic look of Prusa style printers with all the swirling and loose cables.

I have no experience with Delta style printers altough I want to build a mini- kossel. The 2 advantages for the Delta style printers is height and faster print speeds altough I am not really convinced with this last one because in my opinion the print speed is not limited because of technical reasons but by print quality. Alltough my Mendel90 can print on 70 or 80 mm/s I will never do it because the print quality is less compared to 60 or 50mm/s.

[Patola]

Delta style printers have a static heatbed so they don’t swing the printed part back and forth, which is a great advantage. However they also vibrate a lot, if you can solve that problem you’'ll have assured quality. The effector is naturally faster than a common cartesian printer.

As for the prusa vs. mendel90 issue, I am not sure the flat frames will give the stifness it promises. My chromated rods are pretty sturdy and regular, thank you.

[Lukelektro]

I have no experience with delta printers, but I have a mendel90, and it’s great. Compared to a reprap, parts can realy easily be replaced (not that you have to :)), you can reach every part, frame is nice and sturdy. It can easily be turned on its side or upside down (not sure if it will still print right when upside down, should test that some day )

Compared to a makerbot however, it is quite noisy.

[Jim_12]

I agree that the moving bed is a disadvantage and very few printers still use this. Even the new Velleman is using a static bed now opposed to the moving bed in the K8200.

One of the reasons for the builder of the Mendel90 was to get rid of the threaded rods to make the printer more sturdy. There is a big downforce because the motors and rods are all attached to the flat bottom plate. For this reason the Mendel90 must be one of the most stable xyz printers around right behind the 3d printers build in metal frames.

[artexmg]

For me, the two more important advantages are:

The Z axis. While in a cartesian printer the Z axis move is given by a different mechanism than Y and Z axis, in a Delta printer all three arms are actionated exactly the same way.

As the actuator is lighter (as per design), you have less inertia to break, thus, you can increase the speed without lossing quaility.

That being said, not all Deltas are the same. You need to have a very well build frame, with the right geometry, otherwise all advantages are none.

[artexmg]

Well, I do not know about Kossel, but the Rostock Max V2 kit is very well designed that you practically have no troubles with the geometry.

I had built a Rostock V1 and I had to take care of geometry troubles, true.

However, these issues were fixed with V2. I already had built two Rostocks MAX V2, and both are geometrically correct. The precission/acurracy is great!

[MD3DDelta]

Hello All , i was started with 3d printing last year oktober , with delta Kossel mini.

i build it bigger so the heatbed (200x200mm) fitted on , i wanted to print abs ,pla , and all others .

Build volume 230mm in round and 260mm hight. Extruder is MK7-based-i tuned it up for flex and so on .

Hotend is the bowden with also tuned up cooling. also easy changing hotend .Look the picture.

I have to close around the printer with plynwood .the heat is gone to fast. Stil working on it .

Make absorbers under it ,and the printer is stady, i made also stabilators for the legs ,now he is stiff and goes on.

Finaly, the printer was fast builded and not expensive (€400).

The calibration was an other story :

Nothing on the internet was really helpfull.only an few people pionted in the right way.

like Rich Horn :Richrep. thanks to him , i made my own guide for the printer .calibration is not that hard .anymore.

Like driving an car ,you must learn to handle the machine ,every machine .and on you go.

The printer is fast .an friend has the mendel 90 ,well tuned and is 2x slower then mine .

And it is accurate.Mine level is high, 0,10mm with nozzle 0,30mm 1,75mm filament.

Our baby sleeps next door .and never woke up ,and the doors where open , silent it is .the vents makes most noise.

The only cons of the delta is ,For me , i can’t print with 2 hotends ,so with multycolourprints ,i programmed the gcode .

to an parking level and change filament then resume print , never had an problem with that ,it take only more time to

programm but this is also learned easy.

Next printer is the big mendel i think with makerbeam alu.and closed compleet .Like Richrep made one .

I still want to print in 2 or more colours in one run .

If somebody want : the guide i made for me is in the marlin software build in .

So i can send it to you as zip .Just ask . You can use it for other printers as well , it is an guide for handle and doing.

3D-printng is working with high precision machines , well tuned ,makes it every thing you want .

I have printed now with mine 2 delta’s kosselmidi 8 spools = 8KG. and only 600gr carvisch rest.in just 12 months.

is that good for an Newbee ?

thanks for reading all and keep up printing .!

[CopabX]

The y-axis is stabilized using a plate similar to the plywood plate I used on my i3. I realize now that my response was unclear, but the point I was trying to make was that with a base plate I’d expect it to be on par with my i3. Sorry for the confusion.

As for cables, it really depends on how you manage the wiring and whether you use a RAMPS, Printrboard, etc. I use a Printrobard so there are no seperate motor controller modules and minimal wiring.

[elmuchacho]

Nice write up and cool mod on your delta. I’ll definitely be interested in that guide. Pretty good on your 8kg I’m on 14kg in 8 month

[MD3DDelta]

hello elmuchacho, i have setup by github the files from the guide .

you can download it there .: GitHub - MD3DD/Calibrationguide-Delta-and-others: An guide for calibrate the delta and other printers ,it is written in the Marlin ,for direkt working proces .

cheers md3dd