Einsy Rambo on MK2.5  

Re: Einsy Rambo on MK2.5

you probably need to tune the drivers settings for skip detection and sensor-less homing. it's voltage, stepper motor dependent far as i know. possibly even less reliable at 12v. 24v is really ideal for the most part. also the drivers may produce high pitch whine noise at 12v since the chopper frequency is voltage dependent (my TMC2100's from Watterott did). except for stealth mode, it's silent regardless.

Re: Einsy Rambo on MK2.5

Very interesting, thank you for your reply

Re: Einsy Rambo on MK2.5

I completed mine yesterday. I now have a Mk3 with the Einsy RAMBo in a Haribo 3030 extrusion frame, running a Mk2.5 12v heated bed with removable sheet. The bed is running off a 12v Mk2S PSU and the rest of the printer is running off a 24v Prusa PSU. Both PSU's are mounted on the frame and because neither is under full load they both stay cool and should last a while. I supply the Einsy with 24v only and switch an external MOSFET board which the 12v PSU is linked to for the bed.

The printer is gorgeous. It is as quiet and well behaved as my Mk3, all the Mk3 features are turned on and I am running the latest 3.1.3 Mk3 firmware and loving the removable steel sheet bed.

Now I just need to wait for the powder coated sheets so I can get two of them for my vouchers and free shipping!

Working out the full Mk3 conversion with the 2.5 bed was well worth it. I wonder if I have the 1st Mk3 Haribo Mod?

🙂

Re: Einsy Rambo on MK2.5

I am guessing you did the Haribo mod before doing the 2.5 kit? I just did the math and for me to upgrade my mk2s to your build would be around 500$ (which is why I recently canceled my 2.5 upgrade and decided on the mk3 upgrade)

Einsy : ~ $110
TMC 2130: ~ $60
Haribo Frame: ~$130(last time i checked)
24v PSU: ~$20
2.5 Kit: ~$180(with shipping and discount)

Re: Einsy Rambo on MK2.5

I am guessing you did the Haribo mod before doing the 2.5 kit? I just did the math and for me to upgrade my mk2s to your build would be around 500$ (which is why I recently canceled my 2.5 upgrade and decided on the mk3 upgrade)

Einsy : ~ $110
TMC 2130: ~ $60
Haribo Frame: ~$130(last time i checked)
24v PSU: ~$20
2.5 Kit: ~$180(with shipping and discount)

Correct, the Haribo mod was completed a while ago giving me a superb Mk2S. But once I heard and saw the Mk3 in operation I knew I had to go for the full upgrade.

It is an expensive and time consuming way of getting to a Mk3, but I have had many hours of pleasure first with the Mk2S, then with the Haribo rebuild and now finally (so far!) the Mk3 upgrade. After all that time in thought, design and work the pleasure of seeing a skew of 0.00 is, for me, definitely worth it. This machine is working away behind me right now and the loudest thing about it is the print fan!

Re: Einsy Rambo on MK2.5

If you have an Einsy board, the TMC2130 driver is what?

Re: Einsy Rambo on MK2.5

Sorry I could not resist... 😆

This puzzles my mind a lot lately!

I decided to buy a couple of TMC2130 from watterott and do my best.

Regarding the Power Panic, it is a very simple circuit, easily implemented on any power supply.

Re: Einsy Rambo on MK2.5

😀

Thanks for all response. What I keep in mind is that Trinamic is really made for 24v.

Re: Einsy Rambo on MK2.5

I have Y-Axis´ length error. How did u solve that on your Haribo-MK3-Hybrid?!

Re: Einsy Rambo on MK2.5

I have Y-Axis´ length error. How did u solve that on your Haribo-MK3-Hybrid?!

That was one of the biggest challenges of the Haribo mod, making sure that the relationship between the locations of the nozzle compared to the three axes were identical to an original Mk3 printer, and that the bed had the same amount of travel and the same endpoints. X and Y endstop switches were removed and discarded as the Mk3 does not use them.

Is your bed able to travel all the way along the Y axis? IIRC I had to make adjustments to the motor mount to allow this. Also worthy of note is that the Mk2S has the Y motor to the right of the mounting whereas the Mk3 is to the left when viewed from the front of the printer. I failed to notice this which meant that my bed was homing to the back of the printer not the front in my first calibrations. A real facepalm moment when I noticed this! To solve I had to reposition the Y motor as in the Mk3 with a custom motor bracket, and ensure that the bed could travel all the way along the Y rods until the LM8UU's reach the Y rod mountings. Then the Y travel was sufficient.

Make 100% sure that your bed can move smoothly without binding. Any glitches in its travel can be seen by the Einsy as the endstop which then screws up its length travel calculation.

At the end of the day your bed must be able to travel the same distance and end up in the same places front and rear from the nozzle as on the Mk3. It took me some hours to achieve this but it give me no end of pleasure to see the standard Mk3 firmware and features running on the Haribo, every bit as well and as quietly as on the Mk3.

Re: Einsy Rambo on MK2.5

I completed mine yesterday. I now have a Mk3 with the Einsy RAMBo in a Haribo 3030 extrusion frame, running a Mk2.5 12v heated bed with removable sheet. The bed is running off a 12v Mk2S PSU and the rest of the printer is running off a 24v Prusa PSU. Both PSU's are mounted on the frame and because neither is under full load they both stay cool and should last a while. I supply the Einsy with 24v only and switch an external MOSFET board which the 12v PSU is linked to for the bed.

The printer is gorgeous. It is as quiet and well behaved as my Mk3, all the Mk3 features are turned on and I am running the latest 3.1.3 Mk3 firmware and loving the removable steel sheet bed.

Now I just need to wait for the powder coated sheets so I can get two of them for my vouchers and free shipping!

Working out the full Mk3 conversion with the 2.5 bed was well worth it. I wonder if I have the 1st Mk3 Haribo Mod?

🙂

Hello Alfred,
While my 2.5 upgrade parts are being printed I found your post.
I am almost following your steps. I plan to mount the 2.5 upgraded mk2 in a bear v2 frame.
I am tempted to order an EINSY board after reading your coments since I have several 24v psu's laying around, and almost convert the printer in a mk3 using two psu's.
-
Did you need to substitude the extruder fans? I read somewhere they have to be 5v for the EINSY and I think the noctua fan included for the 2.5 upgrade is 12V.
- Do you have a link the MOSFET board you used to feed the hot bed? Any dedicated pin to plug it to the EINSY? I don't want to mesh it and I want to be sure that I will be able to wire it correctly.
- Did you have any firmware issue during this time?

I also read your post about being aware of the inverted Y motor position the mk3 has. Any other advice will be much appreciated.
Thank you

Re: Einsy Rambo on MK2.5

Hi there,
I would like to follow the thread started by Gregoire (Bear upgrade designer). COuld we use a single psu@24v and use a step down for the 12v bed?

Re: Einsy Rambo on MK2.5

Noctua Fan for 2.5 should be 5v

https://shop.prusa3d.com/forum/hardware-firmware-and-software-help-f44/which-noctua-fan-did-you-get-with-the-mk2-5-kit--t15383.html

Re: Einsy Rambo on MK2.5

Hello Alfred,
While my 2.5 upgrade parts are being printed I found your post.
I am almost following your steps. I plan to mount the 2.5 upgraded mk2 in a bear v2 frame.
I am tempted to order an EINSY board after reading your coments since I have several 24v psu's laying around, and almost convert the printer in a mk3 using two psu's.
-
Did you need to substitude the extruder fans? I read somewhere they have to be 5v for the EINSY and I think the noctua fan included for the 2.5 upgrade is 12V.
- Do you have a link the MOSFET board you used to feed the hot bed? Any dedicated pin to plug it to the EINSY? I don't want to mesh it and I want to be sure that I will be able to wire it correctly.
- Did you have any firmware issue during this time?

I also read your post about being aware of the inverted Y motor position the mk3 has. Any other advice will be much appreciated.
Thank you

Hi Eduardo

I replaced both fans with Mk3 5v versions, and I also replaced the hotend heater with the 24v 40w version.

The Mosfet I used is a standard readily available item - https://www.amazon.com/BIQU-Power-Module-Expansion-Printer/dp/B01HEQVQAK/ref=sr_1_6?ie=UTF8&qid=1526757290&sr=8-6&keywords=mosfet
It does not require a pin on the Einsy. The control wire for the mosfet is connected to the heatbed output terminals on the Einsy - hence when the printer "switches on" the heatbed it is actually just triggering the mosfet. As the mosfet supply input is connected to the 12v supply then it switches that 12v to the output. It does not matter that the trigger wire has 24v on it.

Firmware is absolutely standard Mk3 release. The printer I built is dimensionally equivalent to the standard Mk3 and has all of the Mk3 features so no changes to the firmware are required.

Here is the finished item - if you look inside the left rear of the frame just under the left Y rod you can see the orange box I printed to house the mosfet. Plenty of space there for it.

Re: Einsy Rambo on MK2.5

Thank you Alfred for your quick and detailed response!!
Now it is much clear for me and your post encourage me to make that modification.
Thank you very much.
Eduardo

Re: Einsy Rambo on MK2.5

I'm having some troubles with my Einsy Haribo. The same Y-Axis error but also strangely my heatbed is heating very very slow. The LED is only on every other second. I do supply the Einsy with 24V for the motors and electronics and 12V for the heatbed. From the electrical scheme this should not be any issue at all, as the two power lines are separate.

Firmware is absolutely standard Mk3 release. The printer I built is dimensionally equivalent to the standard Mk3 and has all of the Mk3 features so no changes to the firmware are required.

So your Y-axis rods are 330 mm as well? The "original" Haribo uses 360 mm rods (which I always thought to be pretty stupid) and now I'm getting the "y axis error" during selftest as well. But only becaue my Y-axis is ~30 mm longer...

Do you have a link to your Y-axis motor bracket? Which belt holder are you using?

Re: Einsy Rambo on MK2.5

So your Y-axis rods are 330 mm as well? The "original" Haribo uses 360 mm rods (which I always thought to be pretty stupid) and now I'm getting the "y axis error" during selftest as well. But only becaue my Y-axis is ~30 mm longer...

Do you have a link to your Y-axis motor bracket? Which belt holder are you using?

Confirm my Y axis rods are the standard 330mm length, not the longer Haribo spec.

Y axis 3030 motor bracket can be found here - https://www.thingiverse.com/thing:2942960

Belt holder I used a standard Mk 3 type with the single slots.

HTH 🙂

Re: Einsy Rambo on MK2.5

So today I was able to calibrate my MK2.5 + Einsy. I inverted the Y-Axis in firmware until I can print the proper mount.

I wanted to make sure and redid self test and I still get the Y-Axis error every once in a while. I suspect the pulley is at fault because the 5 mm hole is quite outside the middle. When moving the axis you can feel that sometimes it moves easy and sometimes harder. Without the belt the bed is moving absolutely free without binding. I guess this is causing the "limit switch" to trigger. I've ordered some new ones.

And in case someone is wondering: the power for the heatbed is completely separate from the other one. I am running 24 VDC for the motors and 12 VDC for the bed with two separate PSUs without any issues. No external mosfet needed.

So your Y-axis rods are 330 mm as well? The "original" Haribo uses 360 mm rods (which I always thought to be pretty stupid) and now I'm getting the "y axis error" during selftest as well. But only becaue my Y-axis is ~30 mm longer...

Do you have a link to your Y-axis motor bracket? Which belt holder are you using?

Confirm my Y axis rods are the standard 330mm length, not the longer Haribo spec.

Y axis 3030 motor bracket can be found here - https://www.thingiverse.com/thing:2942960

Belt holder I used a standard Mk 3 type with the single slots.

HTH 🙂

Thanks!

Re: Einsy Rambo on MK2.5

I am about to replace mine 2.5 stock Rambo mini 1.3 with a Einsy 1.1a using the stock printer frame using dual power supplies the stock 12V form mk2 and a low power 24V for motors and electronics only.
Some thoughts about the issues you have faced guys:
1. Inverted Y direction - the simplest way to invert it is to swap the 2 wires of a single phase for that motor.
Choose one of the pairs pin 1-2 or 3-4 and after swapping them the direction should be fine.
No need to rebuild firmware and print mirrored mountings.
2. Mine Noctua fan (extruder cooling fan), which came with the 2.5 upgrade is 5 volts, so it should be fine with Einsy. For the print cooling fan there is no choice other than replacing it. If I am wrong, please correct me
3. The bed power is the easy part, since Einsy has separate power rail dedicated for it and only for it, which should be perfectly happy with 12V.
4. The extruder heater is questionable piece of work.
The first solution is to replace the heater bullet itself by 24V one, but that causes additional costs: new heater bullet, more powerful 24V power supply.
Another approach , which I would consider is to keep my 12V heater, which makes the work a bit tricky, but saves a lot of work to disasemble, replace and reassemble extruder and wiring. If you take a look at Einsy schematics there are generally Two Input power rails:
Rail1(Pins 1-2): Logic&Motors_in splitting into:
[*] VMOT - Supplying the motors
[*]+12V2 - Going to J19 (whch seems to be unused) and supplying the extruder heater via Q1 (NFET switching the heater ground)
Rail2(Pins 3-4): BED IN - Directly supplying the bed via Q5 (Same NFET as Q1 in the same configuration) on ping 5-6
Bed should be fine if pins 3 and 4 are supplied respectively with +12V and GND from the original MK2 power supply.
But there is a workaround for the extruder heater - its ground can be driven via Q5 and the other wire could get removed from the connector and attached on the pin 3 (12V via external 5A fuse). This way we are about to use the integrated MOSFET swich on the Einsy board and get it working @12V.
The only drawback from this solution which I can clearly see is that LED2 and LED6 (BED and EXTRUDER Heater indicators will not be able to completely turn off. I don't belive their current flowing through the heaters will cause any noticeable additional heating in the heaters themselves).
Since these two rails are monitored (not sure if implemented in firmware, but the hardware supports it) there may be complaint about the voltage level out there. This is easy to work around by soldering additional 10K resistors in parallel of R55 and R66 if necessary.
5. After the previous five, the Logic&Motors_in rail becomes truly Motors and Logic, with no heaters on it and supplied by 24V lower power SMPS - 50W. My current measurements on 12V with Mini Rambo from lab bench during XYZ Callibration show current less than an AMP. If the power budgets on the new trinamic drivers is the same that would mean half Amp @24V That could not be true due to the larger acceleration and trevel speeds of MK3, which will definately require more power, but even if it is doubled (unlikely) it is still pretty small 24V load.

I am open for any other Issues which I may face or any suggestions.

BR,
Angel