I don’t think Ada would mind me sharing this. ada-fang@formbot3d.com

Hey Frank_66, I’ve been in touch with Ada a few times but with the time difference and the slight language barrier, it’s hard to get a hold of them. They’re actually sending out a new needle for my BL Touch sensor. The problem with my extruders is that extruder one failed to go back home after the auto home and when running the 2nd extruder test, extruder 2 bumped the 1st one and jumped the belt. Ever since that occurrence the 2nd extruder has been making a weird noise, jumpy belt, and isn’t able to find its way back home to its dock correctly. It’ll try to run further past the sensor. With the Z axis motor, I think the on board computer got confused with simplify3d so on my screen on the printer it’s blinking x? y? and z?. The Z axis then got stuck around 200mm Z height and wouldn’t come down because it thought it was at zero. I turned the motors manually with my hand with the printer off to bring it back down (was that a bad move?). Now, I’m not sure if it’s not perfectly leveled to the bed but the Z movements are very slow and also gritty like the 2nd extruders movements. Can you tell I’m lost and have no experiece with 3d printers? hahaha

Well Joe, it sounds like you have a different machine. My extruders are mounted to the same carriage. Where one goes, so goes the other, they are locked to a constant distance apart. So I’m sorry I can’t give any advice on that. It sounds like they need to have their home positions re-configured but I wouldn’t know how. Like I say, mine are locked to the same carriage a fixed distance apart.

The only way I know of to reset the machine is to re-install the firmware with the original settings. It is loaded on the SD card that came with the machine. Now, I don’t have a lot of experience with this either, I’m new at 3D printing, I bought the Formbot TRex 2 last year, it is my first and only printer. I know after I start mine up the BL touch sensor will check to make sure you are off of the bed. If you are not, it will blink and won’t allow the extruder carriage to move at all. So you have to raise the extuder up to get BL touch off the bed. So if you have a problem with BL touch that may be causing your printer to lock up.

My biggest problem with the machine was getting the Z offset calibrated correctly. That was why I sent that little procedure, I wrote the steps down so I wouldn’t forget. You send the printer carriage home and slowly move it toward the bed until it touches a piece of paper. Then you read the Z offset and install it in the firmware. Then save to eeprom. Then run an autocal routine.
Sorry, cant help with the extruders running into each other problem. They must have revised the machine since I purchased.

The newer T-rex 2 is the same. We essentially have the same machine mine is also fixed to one carriage. I think the second extruder just jumped off the belt and is not in sync with what x value it thinks it’s on. As far as the Z value, I don’t know why it’s so gritty when it’s moving up and down. It could quite possibly be that one side is higher than the other. You said the firmware is on the SD card they send the printer out with? Might have a look at that tomorrow then.

yes, formbot also had me grease my Z position screws. It could be you have some plastic or dirt on the screw threads? In fact they had me clean and grease all of the slide bars and the screws. Also as far as height of the X axis, you can take a ruler and measure off the bed to the X axis mounting bar. Should be exactly the same on both ends. If they are not you can move one stepping motors up or down until both sides are the same. When I first start my machine I will do a homing procedure. If BL touch says it is OK, the machine will drive all the way in the Y direction until it hits a small limit switch. It now knows it’s Y position. Then it will drive all the way it can in the x direction until it hits the X limit switch. It now knows its X position. Then it will drive to the middle of the bed and lower in the Z direction until BL touch hits the bed. It now knows the Z direction. Now it is ready to print. Your limit switches should never allow your bed to move beyond their zero position. I had this problem, my limit switch in the Y plane was broken and the bed went too far. I purchased some spare switches since then. Now also, to load your firmware, the G-code is written with Arduino software. So you should also have the Arduino software app on your SD card to open your firmware application software and connect to your machine. On the SD card in the User Manual folder there are instructions.

something is definitely wrong with my x limit switch or the programming is confused because it will run all the way to home on the right and try to go further. As far as the z axis, I can not figure out why it’s so slow and gritty. it seems to have a stutter when moving and sounds like there’s something working against the motor. I ran the BL touch and the sensor touched the bed but still tried to run lower than the bed level.

Well Joe, when you send the machine home it should go left until it hits the x limit. The x limit switch should stop the motor and the limit tells the controller it’s X zero position. I’m not sure but it sounds like from zero on the left if it is running too far right, the span might be defined incorrectly in the firmware. Or maybe the X limit wiring isn’t seated. You can try tracing the wiring from the limit switch back to the control box and make sure all connections are good. There is a section of firmware that defines the size of your bed. Once it hits the x limit and knows zero position, it should only be allowed to move 400 mm to the right. There is also a section that defines how many mm/step your motor moves the bed. These have to be set right, but I would think they would already be set in the original firmware. I’ll try to find these settings. They may be restored if you reload your firmware.

Thanks for all the help and input Frank, I really do appreciate it. You said the firmware should be on my SD card? How do I check which firmware I’m on in my machine and where is the file located on the SD card?

Sorry for taking so Long Joe I had to work today. So I think I may have found out what happened to your machine. So you are using dual extruders. In Formbot’s instruction to use dual extruders they tell you to set the extruders 200 mm apart. I don’t use dual extruders because my prints are usually to large to allow for dual extruders, ( I sent a picture of how my extruders are arranged, right next to each other.) If you use dual extruders and set them up 200 mm apart, you need to change the travel limits in the firmware to 200 mm*400 mm*470 mm. If you don’t do this the controller will think it can still drive your extruder 400 mm span and it will drive your second extruder right off the bed. I’m trying to attach Formbot’s manual that tells this.

As for the firmware, if you look on your SD card, under Marlin Firmware / Marlin / Marlin.ino. Marlin.ino is your firmware file. Double click to open it up. If you look under the configuration.h tab then select edit and then select find, search for "travel limits" . Before you make any changes, make a copy of your original firmware. Change the travel limits to 200, 400, 470. To download the changes, notice I’ve highlighted the upload button in an attached picture. Connect the provided USB cable to your printer and select upload. Arduino will search for your machine and if it finds it, will load your changes to the printer. I’m having trouble attaching pictures, I think I need to reboot my computer but I will log back in and attach pictures in a separate reply.

Hi Joe, these image files might help you understand what to do. I may be wrong, maybe you didn’t set your extruders apart, but it sure sounds like that’s the problem
3.switch_extruders.pdf (672 KB)

im not too sure as of yet which firmware im running but whatever you have on your display on your printer seems to be waaaay advanced than the one on mine hahaha. will check soon and get back to you

Joe, they are probably close to the same. I would think you might have a later version, last time I spoke with Ada they were using R8. Mine is R7. You opened the Marlin file and went to the configuration.h tab? Have you mounted your extruders together or spread them apart? Unless you plan on using dual extruders, you can just remove the second extruder. Then it wouldn’t interfere and you wouldn’t have to worry about changing the travel limit. I would still reload my firmware to original settings.

im actually emailing back and forth with her right now. about to run the bl touch test. ill pull the sd card after im done to see what firmware im on

Ada is really very good. I go to her when I have problems. She always answer’s and helps. It’s kind of annoying sometimes, they will answer only one question at a time no matter how many emails it takes. but they really know their stuff. One night I had a Skype session with them that lasted almost all night long. They actually watched my machine operate over a video chat, and figured out what was wrong.

wow, that’s awesome that they watched it for that long. I completely understand what you’re saying about the one question hahaha. if you ask two questions in one email you can pretty much save one of those questions for the next email.

Yes you have to be patient but they will isolate and solve the problems one at a time. I think it was two months before I got a successful print out of my machine. Another good recourse is Tamas’ Palagi from 3D hubs. He is also on this community. He skyped with me one weekend, I gave him control of my computer and he pretty much taught me how to set the Z offset, upgrade my firmware, Helped me learn to control the printer with G-code through Proteface. He helped with lots of stuff. For free! I’m afraid I might have leaned on him a little too much. He was excellent, but tends to take liberties with your machine. I would stick with Ada for now.

hmmm just took a look at my SD card and seems like the firmware isnt on here

Really? You need that! Should be a folder called Marlin Firmware. If not have Ada forward it.

So crazy stuff happening to your printer Joe? Sorry it took me forever al these replys went to my junk folder and today I decided to jump on here to check somwthing out and saw abunch of replys. So Joe do you have the trex 2 or the trex 2+? If you just have the trex 2 then its either a faulty x axis home button or firmware issues. If you have a 2+ then its different all around. I dont know how it actually works but you basically have 2 extrudes on looks like 2 x axis belts or does it use 1 belt?. Im sure there is 2 x axis homes. #2 extruder probably has a different home like xb or something. Im not sure. But ill take a look at simplfy and see if it has it. I heard for a long time that simplfy didnt habe it set up for dual extruder until recent like a year ago. So with the 2+ im sure its confused because no other machine out there has the trex 2+ setup.

Hey, I have a T-Rex 2+. Im just so lost and wish there was a tech of some sort to figure all this mess out hahaha.