I have a Rostock Max V1 from SeeMeCNC.

I have a Rostock Max V1 from SeeMeCNC. The Rambo board starts up and the printer works except for the hotend. It registers hotend temperatures. It does not heat up the hotend. The lights do not light up for the hotend. I am not sure which terminal it was hooked to. I am told if fuse F3 which runs the hotend was blown that the printer would not power up. I was told that the fuse would blow before the MOSFET. If both are true then perhaps I messed up the firmware. I was trying to prepare it for a switching nozzle. Y adapter. Sigh…this printer has not worked for me for too long already.

You are not the only one with SeeMeCNC machines. One of the two hot end heating resistors blew after just three weeks of light use. When I contacted them they only offered to Sell me a replacement resistor instead of sending me a replacement. I was even willing to dismount the hot end and send it to them for repair but no. I can understand a little company not having a repair or replace system but to charge for a critical part that failed so soon? If someone buys one of their machines get it through Amazon and let Jeff Bezos deal with their failures.

@Kenneth_Cummings when I first got my printer some time ago, they jumped through hoops for people. I have not bought much from them for a while because I am a bit frugal. I know they switched to a larger place lately so they may have tighter reigns on the free replacements. I do not know. At any rate, I have had the printer for a while and messed with various modifications so I can not really blame them for my current issues. I just have to hope that I do not need a new controller board because it seems like the price went up instead of down for the Rambo boards.

@NathanielStenzel can you test it with “stock” firmware to see if your changes caused the problem? Seems like a cheap and easy test.

@SirGeekALot that does seem to be my next step.

@SirGeekALot Well, I was just told by them that I am basically shit out of luck because I have the older Rambo board that came with the printer. They bloated the firmware up so then after you try to use the menu it locks up. Ugh. It would be nice if they kept archives of the firmware longer. They had more, but they got rid of them.

@NathanielStenzel Does it run a version of Marlin? If so, then you should be able to get something from the Marlin github.

@SirGeekALot the folk at SeeMeCNC have you put Repetier firmware on it.

@NathanielStenzel Ok, but if they’re not supporting you, and it is effectively broken, why not try Marlin instead?

@SirGeekALot I suppose I could. I have never used it before and should have a copy of my old firmware on an old hard drive (I like usb enclosures) but I could try it.

I suppose mine is a Rambo 1.1 or 1.1b. F3 is perpendicular to the car fuse. It does not control board logic. After 1.1b, it does, but before and including 1.1b does not have board logic controlled by F3.
@SeeMe_Support , keep that in mind for future questions from Rostock Max v1 owners and ask about the F3 fuse orientation.

“The small white fuse holders are Little Fuse OMNI-BLOCK fuse holders. They are compatible with NANO2 Fuses.
Fast or very fast acting are recommended. The fuses used in the retail RAMBo are rated at 5A with a maximum
voltage of 125V and an example part number for a replacement is 0448005.MR.”

It looks like you should be able to use Marlin:

@SirGeekALot cool. Of course I need to get a replacement fuse before it will do me much good.