Sitting at the computer doing some CAD…emails are a welcome distraction sometimes.
Does it make a difference which endstop location hooks to min or max on the board? As in, does it matter if the endstop on the left of the x axis is hooked to min or max and visa versa?
Where do you guys generally hook a cooling fan up for the Ramps board? It’s just a 40mm 12v two wire I bought from you.
Thanks,
Andy
The min goes with the traditional axis port and the max goes with the E* port.
The fan get plugged into the power supply directly. There should be pictures on the Ramps page found at the bottom of the assembly page.
Ok great
I just fried my ramps putting it back together by a stupid mistake on my part. I shorted straight across the main power plug while it was plugged in. I added a plug for the cooling fan and stupid me put the male pin end on the power supply side. While i was fiddling with getting my case closed i touched those two male end pins to a pair of pliers. The smoke started and of course everything was dead after that. In your experience do the drivers and LCD normally make it through something like this? Could the mega survive? Do you have any ramps stacks that are straggling around? I know you don’t have any in the store but thought i would ask before purchasing elsewhere. Appreciate the help as always.
Thanks,
Andy
Usually it’s the Mega that kicks the bucket. I don’t think I’ve ever seen a ramps board get cooked. Can you post pictures? Screen and stepper drivers are probably okay, they weren’t in the path of the current.
Are you sure it’s not the power supply that fried? Shorting the 12V input should have removed all the voltage and current from the ramps, leaving all the pain for the power supply. The current would still go through the power connector, so that might have melted, but it shouldn’t have put extra current through the Arduino regulator or the LCD.
I’m not sure of anything at this point…I just know when it happened there was an instant puff of smoke right past the green adapter on the ramps where the power comes in…there is some very slight discoloration now in that same area on the Ramps board (I’m not home where I can take a picture)…after it happened I hooked it back up…I had a really weirdly lit lcd…you could make out what it said if you tipped it just right…I could see it well enough to try to move the motors and they didn’t move…I rebooted it a couple times and the same thing. The last time it was on it started smoking in that same area again and I shut it off real quick…now no display no nothing. I’ll probably end up ordering one of the kits with the Ramps, mega, drivers, lcd, just in case. I hope the power supply and everything else is still good. We will see. It’s not a lot of money but what an irritating thing to do…I finally had everything wired back up with the dual end stops installed and working. Enclosure on, wire loom installed, everything looking good, etc. I was just trying to get the board into a case and make it all look nice before finishing up. Look where that got me lol
Aw, that sucks. Well, the exercise of figuring out what happened is probably just academic at this point.
On the arduino, the vreg dies most often.
On the ramps, the drivers might have died, or the mosfets (the biggest design problem with that board is that those mosfets can be bent enough to touch. That is the stupidest thing, IMO). Who knows though, there are more ways to break things than fix them 
.
I am very new to arduino/mega/marlin and how everything works and interchanges, so please forgive me for my lack of knowledge. I am seeing a kit on amazon with A4988 drivers instead of the DRV8825 that is sold here. Does this make any difference to me? Are they better, worse, or just different? I’m not seeing a kit with the DRV8825 drivers that actually have any reviews. Here is the Link i am talking about. If anyone knows of a better kit/source i would be glad to know.
Thanks,
Andy
Andy, most likely what actually smoked is the plastic in the green connectors. Without that power coming in, or only very little of the power coming in, anything that requires 12V will be left unpowered. Also if you don’t have a USB connection to a computer the 5V stuff will also be off. Your symptoms match that, since the steppers and such use 12V and the display uses 5V. When you were getting a faint image I bet there was just a trickle of power getting through that melted plastic.
Easiest fix is obvious, replace the RAMPS. Harder but still doable is to replace the green connector. Unsolder it off the board and solder a new one in place. Don’t try it if you’re unsure of your soldering skills since it’s not out of reach to lift a trace up when unsoldering the old one, breaking the board more completely.
You can use the A4988 drivers, but you’ll have to tweak the software since they don’t support 1/32 stepping. There’s not really a large cost difference between the two types, so I always go with the better DRV8825 drivers.
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Ok thanks a lot for the info…Do you think the lcd is probably good??..ok I wondered which driver is better, I’ll definitely go with the drv8825’s then.
Since I’m on this topic and I haven’t ordered yet. Is there a board that cost marginally more than the Ramps that is a worthy upgrade, that would still function exactly the same as far as firmware and capabilities?? I wouldn’t mind to spend a little more but not quite ready to lay down the cash for a full Rambo…the mini won’t work for this dual end stop setup of course.
I see that these Ramps kits are branded differently on amazon…Do the brands mean anything at all or there all just the same thing?
From what I’ve seen, ramps are ramps. Some use better components, and others color code their boards differently. For the price, they all pretty much seem to do the same thing.
That’s about what I figured…thanks
Finally got my machine back together. Its about 1 a.m here. Pretty excited about this, i think it will really help me. I am running into a small issue though, that i hope i can get some help with. When i move either axis far enough away from the end stops, they move a certain amount and then stop like they have hit end stops when they really haven’t. When it does it, it seems to move the same amount of distance before hitting the non existent end stops. I can hit home again and it will go the rest of the way and home properly. I have no idea but could the firmware only be allowing it to move a certain amount to home, like the machine had a set size or something? When it reaches that “Size” it tells it to not go any farther as a fail stop?? I know very little about the programming/firmware side so i am just throwing out a thought. I have some videos to put together of the swap over process including video of this issue i am talking about. I hope to get it put together and submitted for the contest if there’s time (Had to wait for another ramps stack). If not ill put just a video up of the issue if necessary.
Thanks,
Andy
That’s usually electrical interference. Your endstop wires are inducting a small voltage from something and it’s tripping the endstop circuitry. Mine does that occasionally too, but I’ve never had an issue while milling something. Not sure if the endstops are active while milling.
No, I think that’s the software endstops. The is an x and y size set in the firmware. In Configuration.h.
If you comment out MAX_SOFTWARE_ENDSTOPS. Then that should take it away, or else you can set the bed size right above that in the file. The default is 200mm, but I’m not sure if Ryan’s default is something else.
Where do I adjust how much the z axis raises before homing?
Thanks
Pretty sure it’s the clearance setting.
I know about that setting in estlcam but that’s not the case for this particular thing I’m talking about…If you home without any g code entered it still pulls the Z up before homing…I thought I seen where Ryan said he set this distance in the firmware somewhere??