3DR "Simple" Delta Printer

M119 reports the following:

13:57:39.745 : N50 M119 *63
13:57:39.747 : Reporting endstop status
13:57:39.747 : x_max: TRIGGERED
13:57:39.748 : y_max: TRIGGERED
13:57:39.749 : z_max: TRIGGERED

I disabled the x,y,z min end stops using "-1" and reuploaded Marlin. It still does the same thing. It homes just fine but will not move in any axis using manual controls.

Well, I ditched Rich's version of Marlin and tried the Kossel version Marlin here : [github.com] I have attached the configuration.h for the delta Marlin. Rich's version of Marlin was quite old and doesn't support some of the newer features that are really required, especially by the #dr Simple, like M666 to adjust the endstops in software. I might remix the 3DR simple carriages to include a set screw for adjusting the endstops.

After some configuring, I am able to get the 3DR to home correctly and then move - somewhat. I still can't get it to print at all. It homes, then if I command a move in a direction, it forces itself and ignored the endstops resulting in grinding. I move it down to something like Z50 but I have to manually type in the commands i.e. G1 Z50 F5000 to get it to move. Clicking on the Z icon to move in Z on Repetier moves SOOOO slow it's almost imperceptible.

Can someone who has theirs running please attach your Marlin directory and possibly attach their slic3r profile?

To be honest, I'm kind of deflated. I've setup a few cartesian printers and they were a bit tricky but nothing like this. It's taking me hours and I feel as though I'm no where close.

Thanks!

Edited 1 time(s). Last edit at 03/16/2014 05:11PM by umdpru.

My 3dr is very alive now. Must if my issue was with repetier host. For some reason repetier will not start the print. The 3dr works fine from interface, though. I feel much better now that is working. Now to tuning

Yikes, looks like this thread is dead ?

Quote
umdpru

Can someone who has theirs running please attach your Marlin directory and possibly attach their slic3r profile?

I'm going to take a liberal definition of the word "running" since no one else has replied yet. Here's my Marlin directory and slic3r profile (I just barely got mine printing tonight! .... kind of...almost...hopefully?):

Marlin directory (including the latest .hex file that I uploaded to the Printrboard): [www.dropbox.com]

Slic3r config: [www.dropbox.com]

and here's a short Instagram video showing that I've kind of almost got it working.... [instagram.com]

edit:

a few hours of tinkering and I traced the big issue I was having to the set screw of machined spindles that wasn't tightened enough, so the motor shaft was spinning freely inside the spindle. Working MUCH better now! [instagram.com]

The first successful print - RepRap logo!



Thanks for all of the effort you put into the design and documentation John!

edit #2:

To get the extruder to feed the correct amount of filament I had to set the M92 E value pretty high, I think somewhere near 700. The default firmware value was 90 or so. Does that line up with what everyone else has been seeing with this build or is that indicative that I've got something wonky going on?

Edited 6 time(s). Last edit at 03/18/2014 11:08AM by PierreB.

Realized that my x-axis was mirrored, but that was a quick fix by reversing both the X and Y motor connections along with the X and Y endstop connections. Got a few more test/calibration parts printed and pretty happy with how the early parts are coming along:

The Rostock MAX 250mm calibration cylinder scaled down 75% to a 187.5mm cylinder printed pretty well:


although there is some kind of repeating artifact along the sides, an upward curve seen in the photo below has a corresponding downward facing curve on the opposite side of the part (anyone seen this before? the side of the part has an ever so slight waviness to the surface as well corresponding to the pattern you see):


and a few other calibration parts:


edit:
The designer of the calibration cylinder replied to my 'made' post on Thingiverse:

Quote

The pattern is due to positional accuracy limits, bound by your stepper motors' degrees per step.

Edited 2 time(s). Last edit at 03/21/2014 12:28AM by PierreB.

In the X-Y plane, you can get this effect from micro-stepping of the extruder. Its commonly called moire effect, where a repeated 'waviness' happens as the lines are extruded. This is caused by the systems extrusion being too close to the available torque of the extruder. If you look at the extrusion from top-down, the extruded material would not be constantant, but look more like an hourglass shape wave. This is due to the torque of the motor during the micro-steps. Ways to fix this is higher current on the driver, gearing your extruder, higher steps/rev motor, etc.

Now your upward/downward curve is not the same thing. The moire effect I explained above is extrusion related, and even though cumulatively it looks like a pattern, it is still random in nature. This curve you show that follows in the Z axis has to be something else. My best guess is that it is either something not mechanically true, or it may be caused by the line segmentation of the firmware. By this I mean, the firmware does a trick to make things 'straight' in the Z axis. The firmware still receives g-code movement commands in the traditional cartesian format (go right 1 mm, go up 1 mm). Obviously what makes the delta style printers so cool is the arms move in a coordinated way to accomplish the task. The firmware will take the cartesian coordinate and calculate the distance each motor needs to go to get from point A to point B. The problem is that while the arms move at the same time, the direct path thy would take would not keep the nozzle confined to the Z plane. Think about a position where one arm is almost flat and the other two arms are almost straight up/down. Then command the nozzle manually to move to the opposite side of the printer but not have the Z distance change. The linear movement calculated would end up with the nozzle moving in an arc, dipping down in the middle of the move. Now, there is a trick in the firmware to counter this. It takes each g-code move command and breaks it into a bunch of tiny moves. This way the stepper pulse conversion ends up with a bunch of tiny 'dipping' moves that start and stop in the same Z plane to the point where it is no longer noticeable. This trick is limited by how many segments per second as a setting in the firmware. So a bunch of tiny moves in cartesian format would not be turned into a million micro moves in delta movement. Since you are printing cylinder, arc movement is already broken down. So maybe what you are seeing is an effect caused by the cartesian conversion coupled with constant arc moves.

I have no idea but its a guess.

Quote

The pattern is due to positional accuracy limits, bound by your stepper motors' degrees per step.

If this was the case, people would see this effect with any type of printer.

---

"Never argue with stupid people, they will drag you down to their level and then beat you with experience."

I believe the "curve" you're seeing is also a Moire pattern, which is a result of the stepping from the three towers. When you're dealing with a Cartesian printer, the circles require moving the X and Y only, so the stepping patterns will be the same for every layer. However with a Delta, the X, Y, and Z are all moving. This means that the pattern will shift a little when you change layers. I hope this make sense. I have to leave shortly, so this is just a quick note.

My extruder is not assembled yet because the motor shaft is not long enough or the plastic body is too thick where the motor attaches.
I don't understand, all the rest of the body and idler assembly are aligned. but the hobbed blot from Printrbot does .....Augh

I have the motor on the wrong side.....gears and motor need to be on the correct side.....now it works....

Edited 2 time(s). Last edit at 03/21/2014 07:06PM by RTurnock.

Hi,

I've finally gotten around to setting up Arduino1.0.5 so I can build more recent versions of Marlin for the Printrboard. My plan is to experiment with adding Johann's automatic bed leveling with force-sensitive resisters. I have his branch downloaded and just need to do some wiring. But before I do that, I have this memory of someone mentioning another branch that people really like, but I can't find the message(s). Does this sound familiar to anyone?

I didn t want but had to change all parts. It still looks like john s simple 3DR but it is only the look.....

No exotic linear bearing system...I will use normal and cheap stainless steel shaft in combination with Brass bushings
No extrusion based or US hip hop frame but a simple 16 mm ALu-tube for the stability
No China bearings but german 8mm Brass bushings
No fishing lines...they are good for fishing...for printing...it is ok...if you have time to fish the print

The carriage has been changed to fit 8mm Brass bushings and a belt
The base has been changed to fit the alu tube
A new part has been added to form the under-base where the electronic will be housed

Still to do:

Where is the proximity sensor that will tell to the RAMPS that the alu bed has been touched....





PS: I see more and more new accounts created in the DELTA forum. The problem is that the "vocabulary" and "exprience" of the new users has nothing to do with newbies....so I am not yet sure...Is it a cartesian anxiety as Descartes described ? :-)

Original post: [forums.reprap.org]

---

video of my 3DR

A few thoughts after having printed a handful of things on the Simple Delta:

• It makes a fair amount of noise when moving the print head around, much noisier than my RRP Mendel or Printrbot Simple was. I think the noise is coming from the LM8UU linear bearings, but I'm not entirely sure. Anyone else experiencing this?
• The top mounted spool holder is awesome.
• Has anyone mounted a LCD to their Simple Delta yet? I have a Printrbot LCD screen that I'd like to add, but am curious if anyone has already done so and if so how you went about it.
• I seem to be having an intermittent problem with the motor/spool at the rear of the printer. I think it might be that the set screw in the spool keeps working itself loose so the motor shaft is spinning freely inside even though I tightened the setscrew a decent amount. I tried running a 7 hour print two nights ago and happened to have a time lapse video of the failure: [vimeo.com] Maybe it's time for some Loctite?
• The printer is so light that it moves around a bit when printing. I'm going to see about getting some rubberized feet to put on the bottom.

Other than that, loving the printer so far. Very easy to transport and happy to have a functional delta now!

Quote
PierreB
[*] I seem to be having an intermittent problem with the motor/spool at the rear of the printer. I think it might be that the set screw in the spool keeps working itself loose so the motor shaft is spinning freely inside even though I tightened the setscrew a decent amount. I tried running a 7 hour print two nights ago and happened to have a time lapse video of the failure: [vimeo.com] Maybe it's time for some Loctite?
[/list]

You could use an Aluminum Filament Drive Spool



[www.amazon.com]

Printed spools are not perfect, the radius is never exact. It is difficult to push the fishing line throught the 2mm holes ans as you described it becomes loose with the time. But an Aluminum Filament Drive Spool costs money, shipping costs and time.

For these reasons, I am using normal GT2 belts and pulleys.

---

video of my 3DR

Quote
zacbot

Quote
PierreB
[*] I seem to be having an intermittent problem with the motor/spool at the rear of the printer. I think it might be that the set screw in the spool keeps working itself loose so the motor shaft is spinning freely inside even though I tightened the setscrew a decent amount. I tried running a 7 hour print two nights ago and happened to have a time lapse video of the failure: [vimeo.com] Maybe it's time for some Loctite?
[/list]

You could use an Aluminum Filament Drive Spool

Already using the aluminum spools.

Oh!....then I can t imagine the spool getting loose...

There are still three players in the mechanism.

- The fishing line could be too thight.

- The bearing on the top is sometimes blocking.

- The smooth rods are not perfectly parallel. This will stop or make it hard for the carriage to move to the top causing the motor to skip and loose steps. This will also explain why the problem happens as it moves higher during the print.

- The smooth rod or the bearing could be dammaged

What ever it is, it needs to happen only one time during the print...even for a fraction of seconds...the print is lost.

PS: your smooth rods looks like they have deep-seated rust or is it something else ?

Hope this helps.

---

video of my 3DR

Quote
zacbot
Oh!....then I can t imagine the spool getting loose...

There are still three players in the mechanism.

- The fishing line could be too thight.

- The bearing on the top is sometimes blocking.

- The smooth rods are not perfectly parallel. This will stop or make it hard for the carriage to move to the top causing the motor to skip and loose steps. This will also explain why the problem happens as it moves higher during the print.

- The smooth rod or the bearing could be dammaged

What ever it is, it needs to happen only one time during the print...even for a fraction of seconds...the print is lost.

PS: your smooth rods looks like they have deep-seated rust or is it something else ?

Hope this helps.

Just got around to checking this out and turns out the set screw had indeed worked itself out, oof!



The smooth rods (and linear bearings) are indeed rusting :-\. I bought them new from Misumi, so I'm not sure what the deal is. The smooth rods on my RRP Mendel haven't rusted, nor have the bearings there.

It seems that I'm back in business after just tightening that spool set screw back down. If it happens again, I'll probably take the spool off, drill a shallow dimple into the motor shaft and then loctite the whole thing in place. Anyhow, I just managed to print the 200mm twisted vase without issue! Printed with the slic3r spiral option, was very neat to watch print on the delta platform. I'll upload a timelapse shortly as well for anyone interested, but for now here's a shot of the vase after the spool fix:


Edited 1 time(s). Last edit at 03/31/2014 12:28AM by PierreB.

Great that you fixed it. But I must say, I hadn t yet this kind of issue and didn t try out this alu spool. For me it means either the quality of the spool fixing system is poor or the motor has to fight unusual resistence. How is the noise when printing, is it loud ?

I also haven t seen rusting rods yet...Do you have a link to the rods you bought? The rust will probably dammage the bearings the more the printer is in service.

But the print looks very good!

---

video of my 3DR

There is a nice trick I learned for keeping the set screws from coming out. If you screw in a second set screw, it will act as jam and keep them both in place.

Hi everybody!
I started building a 3dr simple some time ago and yesterday it made its firsts couple of prints, post:3DR Simple (warning: its in spanish)
just like to thank a lot to Richard and John for the awesome work they made on the 3DR

Quote
PierreB
A few thoughts after having printed a handful of things on the Simple Delta:

• It makes a fair amount of noise when moving the print head around, much noisier than my RRP Mendel or Printrbot Simple was. I think the noise is coming from the LM8UU linear bearings, but I'm not entirely sure. Anyone else experiencing this?

Yeah, LM8UUs are noisy, specially the cheap ones. Replace them with PLA printed ones and you will almost only hear the motors. My 3DR-S uses them and I they work very well. Autolubricated bronze bushings also work great, and are really cheap. I use them in my Rostock. The level of noise is the same as the PLA printed bushings, but they will surely last longer.

You can also use moderate accelerations and jerk to reduce noise and vibrations. I use 700mm/s2 and 8 values.

Finally, after being distracted by repairing my Mini Kossel and a new delta drawing robot project........
My Blue 3DR Simple is working. First print today of 5mm pyramid. Only problem is that I do not have 12volts at the fan pins so I may need alternatives, like direct wiring or desktop fan.
Thank you to JohnSL for the idea and design files. attached are pictures and a link to a 5minute video on Youtube.
Thanks to RichRap for the original 3DR design.


Video on Youtube of first print.

Quote
psykhon
Hi everybody!
I started building a 3dr simple some time ago and yesterday it made its firsts couple of prints, post:3DR Simple (warning: its in spanish)
just like to thank a lot to Richard and John for the awesome work they made on the 3DR

Me gusto los colores.
Excellente!

>>>>>>>>>>>>>>>
To get the extruder to feed the correct amount of filament I had to set the M92 E value pretty high, I think somewhere near 700. The default firmware value was 90 or so. Does that line up with what everyone else has been seeing with this build or is that indicative that I've got something wonky going on?[/quote]
>>>>>>>>>>>>>>>>>>>

I bought gears from TriDprinting and used the RichRap Greg's Wade extruder modified.......regular NEMA 17 motor 1.9 degree/step.
Printrboard electronics...
M92 X55.50 Y55.50 Z55.50 E520.00
my first attempt, I had the direction wrong and just reversed the connector on the board.
My second attempt, I extruded 25mm and got 50mm, so I doubled the steps from 260 to 520 and then the measured matched the extruded.
The value of steps per unit for the extruder should not be a guess, it is based on the number of teeth on the gears isn't it? and the degrees per step of the motor.
Anyway you can calculate the steps per unit for your extruder.

You should be able to plug the fan into the FAN connector on the Printrboard. This is a PWM output, which means it's controlled via software. Once you enable fan cooling in your slicer, it should work.

Quote
RTurnock
Only problem is that I do not have 12volts at the fan pins so I may need alternatives, like direct wiring or desktop fan.

Thanks John, I will test some more and see if I can get it working.
I have another question.
What if I want to try to use a Ubis hot end on a Mini Kossel?
The 3DR Simple effector is too small compared to my carriages, that is the distance between the diagonal rods is less for the 3DR effector than the standard Mini Kossel effector.
I am not familiar with using CAD and have been relying completely on printing designs by you and richrap and johann and Thingiverse.
How can I get an effector to hold the Ubis hot end with the right diagonal rod distance to fit my MK carriages?
I can scale it up in CURA and then slice it? But then I would have to scale the hot end holder up too and it might not fit the Ubis.
Can not change just one thing.......

Edited 1 time(s). Last edit at 04/11/2014 11:09AM by RTurnock.

John,

Thank you for all your hours working on the 3DR Simple. My Blue is finished but not working very well yet.
I would like to convert from Spectra line to belts.
I have the belts, pulleys and top bearings, this is the same as my Mini Kossel design, so I have experience with belts.
I would like to know your experience converting and how you connected to the 3DR Carriages carriages - or did you redesign and print new carriages?

Thanks
Richard

From another thread, I found out that my fan does not work because I have to change the pin.h for motherboard=81, for the fan from 22 to 16.
There is even a nice note in pins.h buried there that tells you to change it.
Sarcastic remarks float through my mind.....

JohnSL,

Just dropping you a note to say thank you again.
I built my Mini Kossel with a E3D hot end. Then spent a lot of time with clogging and modifying the extruder due to push fit popping out, printing a new Airtripper extruder body, getting a revised design from Jay, printing another body. So, to make a two month long story short, I figured out that I wanted to get longer horizontals and longer diagonal rods to increase the size of my Kossel in the XY dimensions, with less Z height.
Then I was looking at my 3DR Simple knowing I was going to take the Mini Kossel apart, and Wham! I can print the 3DR Simple hot end parts, buy a Ubis hot end and install that on my upgraded Kossel.
I am printing right now the parts for the hot end, I have the jig built to glue the rods, I have the rod materials to make 340mm rods.
The 350mm extrusions are FedEx from Misumi and due Tuesday and Printrbot is mailing me a Ubis hot end.
Yahoo.
Thank you for all the design work you did. Never know how someone is going to repurpose something.

Edit: I meant to write 4cm for 3DR compared to 5cm for MK, not millimeters. I can add 1cm to the effector and get it to work.
>>>>>>>>>>>>>>>>>
OK, well that will not work completely because the 3DR Simple, platform.stl, the effector has 4mm between the diagonal rods but the Mini Kossel carriages have 5mm.
So, I will have to use the MK effector and drill it out to fit the Ubis hot end. Then drill holes to hold the fan mount.
Should probably print a new one for the MK.....maybe just drill the present one out as a first attempt.
Or get the CAD file and edit it.....Oh, but I don't know how to program in CAD......oh well, I will figure it out later this week.

Edited 1 time(s). Last edit at 05/05/2014 01:02PM by RTurnock.

I've ordered myslef a QU-BD one up and given its similar build volume to the printrbot simple and low price point, am considering converting it to a 3DR simple. However I am on a budget (as I'm sure many are) and was curious to know what the price would be to upgrade. After looking around I was unable to find a full BOM so I decided to make one in Excel. I thought I would share it here in case others find it useful. It includes everything John has posted in his tutorials such as printed parts, electronics, pricing, where to buy etc... The only thing not included are the parts for the extruder as there are so many different options out there. If you notice an issue with the BOM or find something is missing, please feel free to mention it so that myself and others have an up to date BOM.

Edited 1 time(s). Last edit at 05/05/2014 06:35PM by CAD321.