Dusting off a R3D beta; issues and upgrades

Hi everyone,

It has been a while since I've been here. I see it is still somewhat active, so I'm hoping I could get some input. I've recently decided to dust off my Robo3D beta PLA+ABS version (early 2014 purchase date in EU). Haven't used it for about 5 years (got other printer + no space for active use). I've had some minor issues and some refitting questions, these are numbered per subject.

Bit of setup info and history. You can skip the parts that are not interesting.
- Stock parts, except for: 8mm rods (which are not entirely straight); hobbed bolt; RAMPS cooling fan; taped bolt of large extruder gear to reduce play
- Smart XXL LCD controller with (at the time) updated Marlin firmware (1.0.5 version)

Had major z-wobble issues, 8mm rods fixed that. Was stored in good working order. First print, about a month ago, looked like the z-wobble had returned for some reason. Had no energy to find the cause. A week ago, had some time and motivation. Cleaned and lubricated lots of parts. First print did not have z-wobble issue, neither does the second one. I am noiticing some ringing or vibrations, but that can probably be attributed to the unstable X rods and screwrods, as well as issue #2.
Also, glass bed is, and has always been, slightly warped in a U shape (Y0 and Y254 are higher than middle, could be simple sag but I doubt that since its glass).
Further issues with the J-head I had: http://community.robo3d.com/index.php?threads/introduction-and-a-few-problems.2420/

1) Preferred software + settings
I don't have all my old settings anymore. Also don't have the knowledge anymore. Used to use Repetier, but the latest was probably version 1.4 or something. Current system only has Voxelizer for my other printer.
I tried using latest Cura. Entered the printer properties and saved GCODE to SD. Printer bed drove itself into the opposite ends, looks like Cura inversed the home positions. Wasn't interested in figuring out the problem. Used Repetier and slicing with Cura Engine worked, but its stock raft setting is very poor (last raft layer is too close).

Any suggestions on recommended or preferred software, or software tweaks.? Exluding Simplify3D.

2) Askew pulleys
I've noticed that the Y and X belt pulleys have a slight wobble when rotating. It doesnt seem that the stepper axis are crooked, but I can't tell for sure without disassembly (especially for the Y). I reckon this resulting 2D/3D fluctuation of the pulley has a minor influence on the translated 1D travel of the belt, i.e. bed and extruder position.

Would this require new pulleys, or is it possible to reseat them (as in, I know it can be disassembled and reseated, just referring to potential single-use damage from this current askew fixation).

3) Parts cooling fan upgrade + software setting value
The stock 40mm DC 12V ?A 2-pin fan sounds terrible now, plus one motor arm is broken. Also, generally, its airflow is not amazing. I've been looking at some 3-pin and 4-pin DC 12V fans (Noctua etc). I know there is no PWM. I guess the fan speed is controlled by the board by regulating the voltage? If so, 3-pin or 4-pin shouldn't matter in that case, right?

Also, the LCD controller has a fan speed range from 0-255. What is this number, and why does it take 2 minutes to reach full fan speed when set to 255?

4) Feedrate / extrusion settings or new printhead?
During the test print, I've noticed some non-optimal print properties.
- Small print areas, that are part of a large layer print area, seem underextruded (e.g. when printing a plate with screwhole sideways, the hole sides are very small in print area); there is a noticeable change in layer consistency and corner accuracy (90 degree corners are rounded off, almost looks like it goes too quick or has too little material).
- Sometimes corner edges are warped upward. I'm guessing this can be attributed to the poor cooling. I have already printed a new airduct (my previous one melted), so haven't had the chance to test and compare.

I am using normal parameters (205C temp, 40mm/s, PLA).

Can this be resolved in software, or is it possible that the stock J-head isn't up for the task? When I had fixed the askew J-head (as purchased) and z-wobble, the printer actually put out some respectable results. So I guess the stock J-head isn't that bad. Is it worth getting a E3D V6 or something like it, or stick with the stock one?

5) General upgrades and recommendations
I am probably going to use this machine for PLA only, as my other machine has way better environment control and capabilities for ABS printing. Are there any recommended upgrades I should look into?
- My plan is to also print and install the X-rod stabilisation mounts

My max budget is about 60-100 euro, or 70-115 USD, depending on the type of upgrades. Not more, as I figure that anything over that could be better put towards getting a cheap new printer (Ender 3 V2 or something).

Thank you in advance.

 

Thanks for the quick and informative reply.

Great, I will try that. The Y stepper is less easy to access, but I'll manage.

Ok. So just switch out the old fan and connect ground and 12V to the same D9 'relay', and leave the PWM and RPM of the fan unconnected?

Alright. I've been on the fence about buying it since 2016, but maybe now the time has come. Do I need the V6 Direct 12v with thermistor or thermocouple version? Also, I figure that Mike Kelly's tutorial still applies?

It hasn't seen much action, just the occasional print. They still feel ok, aside from one spot on the Y-rods that feels like a slight increase in resistance. But that is probably down to the rods, not the bearings.

The only thing that creaks/screeches is the those 'new' stepper couplers that came with the 8mm rods when traversing down from ±Z150 to ±Z30 (not up), not even machine oil could solve that.

And yet, my z-wobble issues were instantly resolved with the 8mm (#1 is 5/16, #2 is 8mm):

 

At the time, I was advised (by this forum and the guys from Robo themselves) to buy the 8mm rods because "it was a common problem on the beta". Maybe it was, maybe it wasn't, but in the end my improvements were more than slight though. And I don't recall any loose(ned) parts. Maybe my printer was 'speshal'.

The Robo is nothing compared to the Zmorph 2.0S I have here; that thing is incredibly loud. Unfortunately, as far as I know, I can't change it out for silent stepper drivers.

Yeah, the beeps, boops and whirrs I am familiar with and don't bother me. However, I am not talking about a minor sqeek or squeel, I am talking about a painfull high-pitched screech like nails on chalkboard. There are no interfering parts or surfaces. While typing this, I figured that I have not yet tested if it is the coupler or the large coupling nut. holding up the X-axis bridge. I will try that first.


Just out of interest, what type of pulleys are present on the beta? Is it GT2 or T2,5, and how many teeth? Could not find it in the Robo3D FAQ document BOM list. Also, out of interest in case I need new steppers, are 0.9° worth getting instead of 1.8°? I understand a firmware config change will be needed, just wondering if mechanically that would make a difference on this machine and its outputs.

The E3D V6 has been ordered along with some other stuff, should arrive somewhere tomorrow. Will look into the required firmware changes, keeping in mind the 8mm rods.
Is it recommended to update to the latest Marlin firmware, or does that not matter? Also, where do I get the firmware for the beta...?

Will update here.
Thank you for the responses.

P.S. reseating the X-belt pulley did not work.

 

At first I had some questions (mainly confusion, it's been a long time) about the firmware and config.h file settings, but after some searching I think I found the answers. Two still remain though:

First off, is this the corrent page and file for the 1.0.x Marlin version? https://help.robo3d.com/hc/en-us/articles/115000723672-Robo-R1-original-firmware --> Old Robo R1 Firmware - R1 Beta ( No Autolevel )

If so, I guess it is just a matter of uploading the Marlin_6_10 sketch in that folder to the Mega 2560? Your (helpful) post here mentions ROBO3DR1PLUSV1.ino, but this one only includes Marlin_6_10 and Marlin (the only two .ino files, both 2kb).

Secondly, I noticed that, despite stating that there is no bed autolevel, the bed autolevel stuff is not commented out in the config.h file. Does that matter?

(yes I won't forget to change the steps/unit from 2267.72 to 2560 and obligatory E3D stuff )

 

Unfortunately, I am unable to properly mount the hotend. Whereas the previous version(s) only used the collet and related recommendation to counterbore an extra 3mm with >7mm diameter for proper heatsink-carriage contact, the version I received (which is edition 2) includes an extra collet clip. This enlarges the required counterbore from 7mm to >11mm/12mm.
Using a spacer instead of a counterbore does not work, as the hotend will drop down too much and the fixation screws bump into the heatsink instead of the allocated recessed fixation area.

Is it possible to run the collet without the clip, and only use the 7mm counterbore? Giving it enough space for the fixation travel of the collet, of course. I do not have 12mm metal drill bit (wood or stone do not work/do not 'bite' into the material) to enable the use of the collet clip with counterbored hole.

 

The current version of the V6 is a bit different than the one in the guide. The older guide (http://community.robo3d.com/index.p...ormation-installation-guides-and-review.3407/ at step 4) recommends to drill a counterbore hole to avoid blocking the collet from not stopping the PTFE tube when retracting, as well as proper positioning and fixation of the heatsink hotend. However, this only includes a collet, as supplied with the older version.

The installation guide for the V6 edition 2, and the product itself, now include a collet clip to permanently fix and secure the collet in a 'PTFE=gripping' state. However, this collet clip requires an increase in counterbore hole diameter of 7 to 11-12mm to enable the heatsink to be pressed against the greg's wade carriage, instead of the collet.
See guide to see the collet clip I'm referring to: https://e3d-online.zendesk.com/hc/en-us/articles/360017013257-V6-Assembly-Guide-Edition-2-

Would installation without this collet clip -but leaving enough space to let it 'grip' the PTFE tube when retracting by means of that counterbore hole- pose any potential issues?

 

Alright. Everything is up and running. I removed the E3D heatblock sock, as it stinks when >150°C. No idea why that is necessary/recommended. The included 30mm heatsink fan is pretty loud / whiny, unfortunately.
Along with some resoldering of lights etc., I have also installed a revised fanduct design with a 40mm noctua fan, that one blasts plenty of cool air.

Overall print quality seems good. The surface finish seems a bit better; tidier and less imprecise. I am working with Repetier, is working for me so far.
I hope the hotend is fixed properly now; it came loose twice during printing (had some play in it). Seems like the original screws don't provide enough clamping force.

A few questions remain though, and one annoying issue.

Any ideas why my fan speed is set to 127 instead of 255 when printing? I have set it to max speed at first layer in Repetier, and the config.h file also shows 255. At 127 the fan does not work, and it makes a significant difference for overhang.

Unfortunately, the Z-wobble phenomena, or something alike, is back. Weirdly, not with every print. It seems that the threaded rod positioning in relation to eachother cause this similar effect. As they are slightly bend, I suspect that when the bend profiles of each rod are parallel to eachother in any given plane at the start of a print, they give the effect of slightly influencing the XY positioning of the head. Any thoughts?

Also, I've noticed that of the X-carriage's sliding bearings, the one facing the extruder side seems to have some play. Can I replace these (easily), and how? Manually or is a press needed?

 

Thanks, I will order those bearings I think. Or is it worth switching them out for the IGUS RJ4JP-01-08 dry ones? Not from a noise perpective (the current LM8UU's don't really make a noise), bur from a quality pespective. Most available LM8UU's are china quality, I suspect (2$ for 2). And SKF's are about 15$ a piece.

Also, resolved the fan 127 issue. While I did have 'full fan at height X' set to 0, at the extruder settings the min. fan speed was set to 50% (now at 100%).

Update on the z-wobble. I have reseated the threaded rods, they are less askew now when rotating.
However, the issue still persists. I have found out its effect is almost not perceivable with 0.3mm layer height, but it is apparent with 0.2mm (pitch corresponding to wobble). 0.1mm shows similar artifacts, but not in sync with the thread pitch and looks more like some underextrusion (as some consecutive layers are correct). Any thoughts on this?

From left to right 0.3mm, 0.2mm, 0.1mm.