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A bit of a slow answer on part I’m afraid life has been rather eventful on my side in the last few weeks.
So firstly I haven’t tested the drivers again as I am not quite sure I understood the procedure. If I am right I have to turn ramps on with the driver and motor plugged in and measure the voltage when it turns on, using this setup?
Is this the right way to measure voltage of the driver?
As for the motor itself, it would seem indeed that it wasn’t wired up properly, surprisingly enough matching the colors to those of the extension wire I bought of ebay wasn’t enough 😀
From fiddling around with the multimeter I’m left once again with rather puzzling answers. I don’t get 4ohms of any combinations. I only seem to get 1.6ohms out of two combinations.
black & green
blue & red
other combinations give a 0. If i understand right I should have the colors in this sequence (BLACK-GREEN-BLUE-RED)?
Thanks Quentin!
I spent the afternoon yesterday fiddling with the stepper drivers, and even though I have 8 of them I couldn’t get a single motor to spin properly, it’s quite depressing.
I went and added the firmware (from your github) on the arduino, and hooked up the motors and pololus. I have both A4988 and dvr8825 (i’m using Nema 17 O.9° motors). Having placed the pololus properly on the shield (checked from successful build photos, it’s misleading how the dvr8825 go in backwards).
I fired up pronterface hoping to tune the potentiometer of the pololus. I was bitterly disappointed to say the least. Either I’m doing something completely wrong or I got 8 duds…
Only two pololus would make the motors shake somewhat uncontrollably (one of which without being told by pronterface) and the others wouldn’t do anything! These things also get really hot (the ones that make movement, the others stay cold), so hot you can’t touch the chip for more than a few seconds.Now I’m aware these are meant, well they it’s normal for them to get hot, but after only a few seconds it doesn’t seem right. I tried to tweak the potentiometer on the “working” ones but it didn’t make much of a difference other than making the movement jerkier or plainly stopping it, tweaking would actually make the motor spazz back and forth. Also the potentiometer is free spinning, there doesn’t seem to a minimum or maximum, how much of a turn does it take to tune one? No matter how much I turn it doesn’t seem to make any difference.
Here’s the procedure so you guys can tell me right away if I did something wrong.
-Disable heated bed thermistor in frimware
-Disable endstops in firmware (comment #define ENDSTOPPULLUPS)
-With everything unplugged, set the pololus and motors
-plug in thermistor of the hot end (couldn’t get a temperature reading either, is there meant to be a way to plug it in? Then again I didn’t bother setting it up in firmware) Since I figured you can’t disable all the thermistors.
-plug in usb, connect with pronterface
-turn on the power supplySometimes when I send a move command the motors have a quick movement like maybe 2-3 steps in a go and then they stop. I’m clueless on this one.
Is there a way to test a pololu by other means like with a multimeter without ramps?
I tried to have a single pololu/motor at a time to narrow down the things that could cause problems, that didn’t help. I also read somewhere that you’re not meant to do that, is that true?Since I’m using cheap stuff (dvr8825 from ebay, A4988 ramps and arduino from DX) it’s hard to pinpoint the issue, not that I would know anyway. The arduino seems to be working fine, screen controller works too.
Should I ask the seller for new pololus or did I somehow fry them?Seems like this build is suffering from delay after delay but I’m not giving up!
By the way Quentin I read the thread on SCARA Kinematics and CPU-Performance, truly facing stuff going on there, sadly my knowledges is limited to understanding what you guys are on about and I don’t have what the skills to be of any help but it’s nice to see the energy being put into it. When I finish my Morgan I’d be happy to help testing 😉
Well this build sure is taking its sweet time, however I’m finally back with some updates 🙂
Staying true to my finances I decided to build a Ramps 1.4/smart LCD controller box in a true RepStrap style, with anything that was lying around, here we go.
The first thing I wanted was a a really sturdy design without anything flopping about when pressing a button. Since I had a lot hardboard from frames collected in the street I decided to go with it for the build.
I had to tailor the supports of the screen to be really snug and precise
The LCD has support on both front and back
The back is a box that holds the Ramps 1.4 with easy LCD connection, the arduino is on a little plate that slides into place.
Finally there’s two fans on the box, one with a dust filter that pushes air in, and one without a filter that pushes air out, it makes one crazy draft in there and should be in theory self cleaning.
The whole unit sits nicely on top of the power supply and will probably be bolted to it.
So there you go, a Ramp/smart controller box that’s pretty neat, costs absolutely nothing to make (wood, fans, and screws salvaged from the street) and has a bit of unique style to it.
I went a bit picture heavy on the post but I figured some might want to replicate it. If you have any questions fire away, if you need more photos of the build to replicate it let me know.
What do you guys think? 😉
Edit:
As for finishing the Morgan itself, I’m still 50-100€ short to buying everything I’m missing and the heated bed got lost during shipping, I probably won’t be printing for another month at least but I’m making progress. Now to tune the stepper drivers.
I printed the mkII indeed I didn’t know what hotend i was going to use at the time I figured it was a structural improvement. I’ll print the mkI.
So the one to print is the 21-Morgan_toolhead.stl right?
https://github.com/qharley/Morgan/blob/master/stl/21-Morgan_toolhead.stl
I don’t think there’s need to remove the mkII just list what hotend each toolhead is compatible with.
Here’s a crude drawing with measurements of the e3d v6 in millimeters.
Knowing that the diameter of the hole in the tool is just right I didn’t measure diameter.
Figured it would be an issue, printing flexible plastics isn’t my main priority though.
On a side note I was going over the printed parts, starting to assemble as I acquire screws and I realized the toolhead is not compatible with the e3d v6. The V6 is too short, as shown in the pictures:
As you can see the hotend is too short to be held by the screws like it’s meant to. I was wondering if you could redesign the toolhead to hold the e3d v6 and match the height the Jhead would have, in order not to have to change anything else on the build?
I can try to do it if you can give me some measurements but I’m not quite at ease yet with 3d modeling with scale.
If you the consider the price and shipping cost of a genuine Jhead (came to about 50€ for me) the V6 is only 20€ more for a fan cooled all metal hotend.
Say Quentin, I was wondering if it would be possible to implement a direct feed rather than bowden on the morgan? My guess is that the motor would be too heavy but I sure would like to be able to print flexible plastics 😉
The doorbell is starting to ring every day or two with a package for me, such a great feeling.
Anyway I’m making progress on the build. Yesterday I received and assembled my E3D V6 hotend, I tested the thermistor with a multimeter and the value changes with temperature so I think I didn’t mess it up.
I have to say the hotend seems to be of really good quality, much smaller than I expected but overall really nice indeed. It has a reassuring snug fit in the tool head and since the V6 is shorter than the V5 I don’t think there will be any adjustment to be made on the morgan.
The assembly of the hotend was extremely simple, it’s like every single detail was though of, no need to force anything, no tape, everything is tightened with screws and the ptfe tubing is provided.
Assembly wise I’d recommend it to anyone, as for performance/morgan compatibility I’ll report on that as soon as my build is finished.
I’m yet to receive the adruino/ramps so there’s not much more I can do for the moment.
One little question however, as I am making the 12mm build I got the bearings and smooth rods accordingly, however I’m not sure if the threaded rod should be 8 or 12mm
Spinning wheels are nice 🙂
I was wondering, any chance you could send me the pattern you used for your metal plate that holds the heated bed?
I’d like to use a design that’s known to work ^^
Those lightbulbs are really good looking too, add some acetone transfer and you’ll have a killer build!
Makes sense, I guess I was worried of snapping the printed parts, they’re actually quite tough!
So far the build is making steady progress. I am one part away from having the complete set, however the last part (08 drivewheel tube) won’t print properly, which has to do with my school’s printer. Should be solved soon however.
I received the nema 17 this morning, I’m still waiting on many bearing and screws from ebay but overall it’s taking shape nicely.
I have to say Quentin I’m falling in love with the design of the Morgan. I find it a very poetic approach to 3D printing.
I was thinking it would be great, as a part of the website, to have a map of the world with a dot for all the morgans. Possibly with a photo of the build and contact info of the person, so if someone nearby wants to build one we can help them out.
I double checked with the original (mk1) lasercutting files and the holes for the pvc pipes match.
I don’t know why it doesn’t fit, I double checked my pvc pipes they have a 32mm outside diameter.
I double checked their length which is right as well, I tried different configurations of cap orders and pipe placement it just doesn’t fit, there’s a good 5cms missing for the 4th pipe to line up.
I think there’s something wrong with the lasercut platform. I did not scale any of the printed parts and the pvc pipes’ caps fit perfectly.
However once the caps are on the platform the pipes cross and I can’t fit the four.
Could someone send me the files they used for cutting their platforms? I’d like to double check but I’m pretty sure the problem comes from the platform.
As for acetone transfer it’s really simple you print a black and white image with a laser printer (mirrored) then put it face down on the wood sprinkle acetone on it and rub, and the ink should transfer.
It’s a really simple method but it gives a great used look, it would be brilliant with your steampunk design 🙂
I went with a heated bed, thanks for the advice.
At first I was considering not using one to take the cost down but since I’m making a morgan for a friend I’m going to need to print ABS.
I got the platform lasercut yesterday but there seems to be an issue with some of the holes. The Z mount holes are offset.
Not that it’s a big problem to make new holes by hand but if it could be fixed for the next person to build a morgan it’d be nice. There’s offset on both halves of the platform.
Platform is a nice 18mm compressed wood, might do an laser printer/acetone ink transfer on it 😀
