The A4988’s should be fine, but that’s another thing that needs to be configured properly in the firmware, and is not in the standard build (it’s set for DRV8825’s).
ooh, that’s good to know! Its possible my friend did it when we set it up, but it’s also possible he missed it.
I see… https://marlinfw.org/docs/configuration/configuration.html#stepper-drivers
I also just checked over the docs, here: https://docs.v1engineering.com/electronics/ramps/
And I noticed that we didn’t add the jumpers beneath the 3 drivers… do we need to if they’re not DRV8825s?
Yes, you still want the microstepping, even if it’s only 16X instead of 32X.
Gotcha!
In the pic in that link, they only show 3 drivers slots with jumpers, but I’m using 5 (two X, two Y, one Z). Should I have all jumpers, under all five drivers?
Sorry, minor question – why did you say
even if it’s only 16X instead of 32X.
? Why would it be only 16X?
Yes, all 5. And it’s because the A4988’s only support 16X microstepping, and the DRV8825’s support 32X microstepping. It’s one of the benefits of using them. 
Ah, thanks Just ordered 5 DRV’s.
So it looks like there are a bunch of potential culprits so far (aside from the general possible Marlin issues):
- I don’t have the jumpers in
- I’m using A4988’s and I’m not sure that’s in the firmware
- My firmware might be very out of date
Could either 1 or 2 be the cause of it stopping, or would they just be suboptimal generally?
Not having the jumpers in means that it would be doing no microstepping. That would have it slinging the gantry all over the place 32 times faster than expected. Which might freak out the drivers, I don’t know. It really does come down to if the firmware is properly configured. But someone else would have to speak up about A4988’s working with firmware configured for DRV8825’s. My gut says they should work, but I don’t know that…
Hmmm. That’s interesting. I’ll certainly use the jumpers and DRV’s when I get them in a few days, but right now they are definitely working with manual control (which I think is just sending g-code still, right?) so I’d think that means it must be okay? they’re definitely not moving 32x faster than expected…
Okay, so I think I need to get new firmware, and make sure it’s properly configured.
Alright, so I looked here: https://docs.v1engineering.com/electronics/ramps/#firmware
and it seems like from here: https://docs.v1engineering.com/electronics/marlin-firmware/
it links to the page with the firmware, here: https://github.com/Allted/Marlin
and I need to choose the right version. I see that I’m going to need Ramps, but here I run into a bit of trouble. First, in the active branches, here: https://github.com/Allted/Marlin/branches/active
the only one with RAMPS is the MP3DP, which isn’t what I have.
If I look at the stale ones, here: https://github.com/Allted/Marlin/branches/stale
I see a few with RAMPS, but I’m confused. I have the first iteration of the MPCNC (Burly, not Primo). Does that mean I want the firmware with V1CNC, is that what V1CNC means? Or do I just want MPCNC?
I.e., this one: https://github.com/Allted/Marlin/tree/MPCNC_Ramps_T8_16T_LCD_32step ?
or this one: https://github.com/Allted/Marlin/tree/V1CNC_Ramps_Dual ?
thanks!
I really wanted to see a picture of your board, and how it is hooked up. That will answer a few questions for me. Some of them have already been answered though.
You don’t need to buy DRV8825s, If your drivers are working, I wouldn’t even bother installing the drvs. The a4498s are good drivers, and if they are already tuned, then don’t fix it until it’s broken.
The a4498s do have different steps/mm, but that is an easy fix.
We recently started a new firmware configuration tool, that cleanly creates preconfigured marlin files for a bunch of configurations. The allted firmware requires Ryan to make the changes manually, so we’re moving to this new thing. It hasn’t flowed through all the docs yet.
Head over to MarlinBuilder releases and look for the V1CNC Ramps Dual. That will have the wrong steps/mm, but you can build that in arduino or platformio, and then change the steps/mm.
There’s gonna be no turning back. No way to save the previous firmware and AFAIK, the 302 is long gone.
It really isn’t hard though. You will need the u8glib directory in arduino. The instructions are in the docs:
https://docs.v1engineering.com/electronics/marlin-firmware/#how-to-flash
You also don’t need inch support. Even if freeCAD likes to send G21s, Marlin will just ignore them. Just always use mm in the file (you can usually still use inches in CAD or CAM, if you like).
Also, I am all for using FOSS software, but I use EstlCAM in ubuntu through wine. It is pretty simple and the estlcam basics show the basic set up. Just an FYI, feel free to get freeCAM to work, and if you’re extra generous, put up a new page in the docs for us mortals to follow.
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Ah sorry! I took pics, but didn’t upload them since it’s the same as the links I posted, and I thought that’d suffice. Here they are though:
(sorry if it’s not good, I tried to take from all angles)
Okay, I’ll try using that tool! Thank you again!!
Ok. It looks like you have the dual endstop version, but no endstops installed. Also, there’s no arduino on there :).
That is the classic Ramps. The V1CNC_Ramps_Dual should be the right firmware.
Awesome, thanks!
The Arduino (Mega I think) is usually below it, I just took the board off in case there was info on the bottom to take pics of 
Cool! Maybe I’ll install endstops at some point, but not now. So V1CNC means the Burly, and MPCNC means the newer, Primo, then?
per your suggestion, I’m using VSCode/platformio. It seems really smooth so far.
Er, should I choose from v502, 503, or 504? I don’t need the cutting edge, I’d rather have stability at the moment.
thanks again!!
Oh, one other question I didn’t see in the firmware docs section – will I need to enter the fact that I’m using A4988’s in the firmware somewhere, before installing it?
Here comes a bunch of random info:
This is all still a bit bleeding edge. The v504 has some bug fixes that aren’t in the previous versions. But if you’re using ramps, and platformio, I think they will end up the same. You can easily leave the settings alone, and then change the steps/mm with gcode.
You can change the steps/mm later, with the gcode M92 X100 Y100 Z400. Then save it with M500.
If you have all the jumpers installed under the drivers, they will be 1/16th microstepping. That’s basically the same as 1/32nd of the drv8825s, except the steps/mm are different.
If you really want to be pedantic, you can change the driver type to a4498, and change the steps/mm to 100,100,400,something. The ramps firmware is set up for drv8825s. So the driver types are set to drv8825, and the steps/mm 200,200,800,something. The driver type doesn’t matter much between those two drivers. They are very similar.
This just occurred to me. What kind of Z axis screw do you have? Is it a leadscrew or the 5/16" threaded rod?
The V1CNC represents any of the MPCNCs, and for the most part, the Low Rider as well. The electronics from the original (couple of originals), the 525 version, the burly version, and the primo version is all the same.
If you end up being tempted to use those drv8825s, make sure you adjust the little trim pot on the top. It should be about 0.7V.
And one other quick note from over here in the cheap seats. For 16x microstepping on the A4498’s, you’ll need 3 jumpers installed under each of the drivers.
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Looking at the bottom of your RAMPS (pic 4 and 6), all of the MS jumper pins are solder bridged. That’s why there’s no jumpers. To use the DRV8825s, you will have to de-solder the middle bridge.
Also looks like you have some burnt joints under the E1 driver. That might be causing you headaches.
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wow thank you so much again! Let me read this, and then go try it… I hope to report back with good news
Ah, good point! i didn’t even realize that…it was a while ago that we did it
But this link: Ramps1.4 - Geeetech Wiki seems to say that for the DRV’s, you can still have all three bridged?
(the last row of their “table” for the DRV.)
thanks!
edit: ah, and good point about the burnt solders. I was worried too, and I think they’re okay. Maybe I’ll resolder if these firmware updates don’t do the trick.