First Build Hiwin slide CoreXY. Need help selecting electrical parts.

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patrickrio
If I go 24v, do I need to do something to supply the Duet 5v or 3.3v power????? or is that already on the Duet????

The Duet has an on-board 5V switching regulator (you need to install JP9 to enable it), and a 3.3V regulator that is fed from 5V. The boards supplied by Replikeo also come with a 5V linear regulator on a separate board, which is used on the Ormerod 2 instead of the switching regulator in order to help the kit meet CE requirements in respect of EMI. Either regulator can be used to supply the 5V. If you use the switching regulator, then I suggest you use a multimeter to check the 5V output, as it may be that Replikeo is not testing the switching regulator. If you use the linear regulator, then my guess is that it will need a heatsink if you use 24V input.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

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dc42
Duet is specified as 35V absolute maximum, Smoothieboard is specified as 12 to 24V. I don't know about the others.

Smoothieboard was designed to handle 35V, but we recommend 24V max so that people are more gentle to the boards

We have some people using 32V with no problem though, but it's under their own responsibility in that case.

OK, I have enough electronics here to do initial setup and testing. I have optical endstops connected to the duet, I have arduino IDE installed and am connected to the board. I have the fan, heated bed, and steppers. I have not updated firmware.

Is there an installation guide for initial setup for a corexy duet?

I assume that I need some libriaries and sketches for the IDE, but I seem to be having problems finding them.

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patrickrio
OK, I have enough electronics here to do initial setup and testing. I have optical endstops connected to the duet, I have arduino IDE installed and am connected to the board. I have the fan, heated bed, and steppers. I have not updated firmware.

Is there an installation guide for initial setup for a corexy duet?

There is a list of resources here [reprap.org]. Here is a summary of what you need to do:

1. Download a binary of my firmware fork (the only one that currently supports CoreXY) from [github.com]. Follow the link to the latest version, then click on the Raw button to download it.

2. See the RepRapPro commissioning guide at [reprappro.com] for how to flash the firmware and copy the SD card files across. I suggest you start from the SD card files used for Ormerod 2. You will need to make a couple of changes for CoreXY:

(a) Add the M667 S1 command in config.g to select CoreXY mode. See [github.com]. I suggest you read the whole of that document, apart fro the section on delta printers.

(b) Change the homeall.g file so as not to attempt simultaneous X and Y homing.

I'll add a /sys-CoreXY folder to my repo to make this simpler in future.

3. Then follow the RepRapPro commissioning guide for general testing and commissioning.

4. The web interface I recommend is DuetWebControl, available at [github.com].

btw on a CoreXY machine, you can test the X and Y motors individually by sending G91 to select relative position, then G1 commands with the S2 parameter will move the motors individually, e.g. G1 X-10 S2 will move just the X motor back 10mm.

Once you have up-to-date firmware, you can also update SD card files via FTP.

HTH David

Edited 1 time(s). Last edit at 05/09/2015 07:02PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

PS you should also change the M574 command to define where your endstops are, and the M558 command to say which axes (if any) the proximity sensor is used to home - default is X and Z.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I have added folder [github.com] to my repo.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Hi Dc42,

I am now getting serious about choosing a proximity sensor for bed leveling. You mentioned your existing product with added bells and whistles. What are the measurements of that board? How much does it weigh? how much does it cost?

Where are you on the miniature proximity sensing only board? when will that be done? what are its dimensions, how much will it weigh, how much will it cost?

Also, since I will have an aluminum heat spreader right below my3mm borosilicate glass, I may be able to use an inductive proximity sensor. What are the electronic specs required for the Duet Board? I am looking at a NPN NO 10-30v 6mm distance sensing unit. will that work?

The Duet can accept most types of proximity sensor. Best is a sensor providing an analog or quasi-analog output (like my differential IR sensor), because then the firmware can slow down the probing speed as the sensor approaches the target height. But you can also use an active-high digital sensor. My most recent firmware release supports active low digital sensors too, which should work OK with your NPN inductive sensor.

My standard proximity sensor board for the Ormerod with hot end fan control etc. weighs about 10g and measure about 28mm wide x 82mm high. The mini IR sensor board weights about 2g and measures 24mm wide x 19mm high. However, the initial batch of the mini board has now sold out. I will make some more if there is enough demand.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I take it there are rules against listing prices???? the mini board is perfect... but they sold out pretty quick, last I asked, about 3 weeks ago, you didnt even have the empty pcbs yet!!! how do I get pricing? maybe I can get raw parts and solder up something temporary???? the weight is much better than the options for inductive.....

I sold the first batch of hand-assembled mini boards at GBP29.50 each + shipping + VAT where applicable. If the demand gets high enough, I will have them produced in quantity, then I will be able to reduce the price. But I'd quite like to have some feedback on the first batch before I commit to another batch to exactly the same design, in case there are any improvements that could usefully be made. I don't have a web shop yet, so please send me a PM if you want to go on the waiting list, giving your PayPal email address, which country you are in, and your VAT number if you are buying on behalf of a VAT-registered EU company.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Hey, could you maybe post a video of the sensor operating on a delta printer? Maybe one with your leveling start-up procedure in operation? It would give a good indication of functionality....

Hi Dc42.

I understand that you had your fingers on the infra red sensor on the Ormeron 2 also. That sensor turns out to be available now and can be shipped for $15 to New York. I ordered it. I may still order yours when you have it available too. How is yours different????

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patrickrio
Hi Dc42.

I understand that you had your fingers on the infra red sensor on the Ormeron 2 also. That sensor turns out to be available now and can be shipped for $15 to New York. I ordered it. I may still order yours when you have it available too. How is yours different????

The standard sensor on the Ormerod 2 uses modulated IR to reduce the sensitivity to ambient IR, based on a mod I did to the unmodulated sensor that came with my Ormerod 1. However, it is still very sensitive to the bed surface, because it measures the amount of light reflected from the bed. On the Ormerod, it is normally used with squares of white paper or white tape at the corners of the bed to serve as targets.

The sensor I make uses two modulated beams of IR that give maximum reflection into the photo sensor at slightly different heights, and it looks for the two reflected beams to have equal amplitude. So it is completely insensitive to ambient IR unless there is so much that the sensor saturates, which only happens if strong sunlight being reflected directly into it. It is also only slightly sensitive to the bed surface. So it doesn't need special targets and works on almost any surface except a mirror, which means it can be used anywhere on the bed.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

ok, good to know. I will still be interested in your mini sensor when you do the next run... and i think i have two others interested too.

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patrickrio
ok, good to know. I will still be interested in your mini sensor when you do the next run... and i think i have two others interested too.

I could order some more PCBs for the mini board now, but I'd really like some feedback from the existing owners, particularly about whether the size, mounting holes and connector need any improvement to fit a wide range of printers.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

totally think you should wait. I have the Ormerod sensor on the way already, and that will work fine as I dial in the printer. it is also pretty small it looks like.

What is the accuracy and repeatability of the mini IR sensor?

Have you compared it to a capacitive bed sensor?

Edited 1 time(s). Last edit at 05/20/2015 07:28PM by veng1.

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veng1
What is the accuracy and repeatability of the mini IR sensor?

Accuracy has no meaning in this context, because the sensor does not output an absolute height. Reproducibility when probing the same spot is excellent, 0.05mm or better provided you are not probing too fast (when used with Duet electronics, the firmware slows down the Z speed as the sensor gets close to trigger height). Reproducibility across the bed depends on a number of factors:

1. Is the bed surface uniform? The sensor is slightly affected by bed surface. For example, switching from plain glass to Kapton tape on glass increases the trigger height by about 0.2mm, and switching from plain glass to BuildTak increases it further.

2. Does the head stay level as it travels? Any probe that does not use the head itself as the probe has to be offset from the head. So any tilt of the head or the bed as they travel will alter the relative height of the nozzle and the probe, leading to errors.

My delta is in pieces being upgraded, but when I put it back together, I'll take some measurements and publish them - and do a video, which some people have asked for.

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veng1
Have you compared it to a capacitive bed sensor?

The problem that I and others have found with capacitive sensing is that it is sensitive to changes in humidity and temperature. This is a problem, especially if you switch between ABS and PLA, because the Z probe is best used when the machine is at operating temperature.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
patrickrio
Hey, could you maybe post a video of the sensor operating on a delta printer? Maybe one with your leveling start-up procedure in operation? It would give a good indication of functionality....

It's taken a while because I was upgrading my delta printer to a larger build size, but I have now done a video. It's at [youtu.be].

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].