(3DP) tuning the Reprappro Ormerod 3d printer

So long as the new board is the correct replacement (it may be an "improved" model, or it may be a different model, in which case extreme caution is called for), I'd change the wiring harness to match the new board. But anytime you order a "replacement" part and some thing is different, double & triple check every parameter, specification, and connection point. Can't count how many electronic devices (some of them extremely expensive) I've smoke tested because I failed to notice things like that. Sometimes even direct replacements move around connectors, etc.

 

I ordered from a different supplier, so I could also get an expansion board to drive additional extruders. A short discussion with RepRap support revealed that they are identical boards with identical pin-outs, the only difference being the Think3dPrint3d boards have screw terminals and the stock RepRapPro boards have pin terminals. They are otherwise interchangeable. So the board will be hooked up and tested today.

 

Thanks for posting about this learning curve. I am watching with great interest with plans next year to get a printer, but only after learning along with you guys.

 

IT'S ALIVE!!!! (again)

As I write this, my Ormerod is doing its first test-print after repairs and upgrades. The new aluminum X-arm is wonderful, but the new firmware and web interface is better. Earlier this year, a fan of the Ormerod decided to make some improvements on the existing software for his printer. Among the changes were a more reliable web interface, a functional print time estimator, and mid-print parameter changing. This last feature is perhaps the most useful, because just now I saw that I was over-extruding and causing a narrow section of the part to bulge out, so I adjusted the extrusion rate down to 95%. No more bulge, and the print is saved! I can also adjust print temperature, bed temperature, and print speed. If anyone else is interested in the improved firmware and web interface, I'd be glad to help you upgrade.
VVaholic, it's true that there is a steep learning curve. But some things you can only learn by experience. I spent almost three years watching and learning from Tugboat's 3d printing experience, but ultimately that only gave me a rough theoretical knowledge of what 3d printers are capable of. I knew enough to recognize if there was a problem with my print settings, but not what or how to fix it. Now, several months after building my own printer, I'm getting better but I still have a long way to go. I still lose probably 1/2 to 1/3 of my prints due to setup mistakes.

 

I have found out that after your print is done and it does not want to come off the bed spray some computer duster on it makes it easier to come off.

 

I'm pretty sure the problem is parts unintentionally separating from the bed before the print is done, rather than manually removing them after completion.
Tugboat, what do you mean by the motors draw more current? They're stepper motors, that the board sends a constant current to regardless of whether the motor is moving or not. That way it locks the axis in place when not moving, so it doesn't drift. I don't know about your currrent printer, but the Ormerod has motor current as a variable you can set with G-code to resist skipping steps at higher speeds. Stock setting on the Ormerod is 800mA, but many people run theirs at 1000mA or even 1200mA. Provided you have proper cooling, of course.

 

How big is the print size?

 

The Ormerod can print a cube of 8" per side.
My printer is currently down because of a complicated jam of the extruder mechanism. I think I know how to fix it, but work has been very busy lately. I hope to get it back up in January, possibly early March.

 

Blarg! I give up. This thing has been far more headache than it's worth. The consistency with which it jams is alarming. Despite trying out a wide variety of filament manufacturers, including top-quality brands and those recommended by other folks on here with printers, it still jams about every other print. I even tried out a brand-new nozzle, hoping that would clear it up. Nope, it jams at exactly the same rate, requiring extensive cleaning with acetone and a precision 0.5mm drill bit. Print quality is reasonable, but it is utterly incapable of printing a circle. Every attempt results in a squashed shape that matches specified dimensions on the X and Y axis, but bulges in other areas. Most recently, it has developed another nasty habit: skipping steps.

It is a very noticeable phenomenon. It loses about 0.2mm per layer along the X axis, causing entire prints to slump over at a crazier angle than a leaning tower of pizza. I disassembled the machine, cleaned, inspected, and lubricated it, and reassembled it, and the symptom is unchanged. I even bought an automotive stethoscope so I could identify the sound of the skipping and pinpoint its source. No luck. I can clearly hear the sound when it is skipping steps, but cannot identify what component it comes from. Every component on the X axis assembly emits the same noise at similar volume.

Enough is enough. I bought this printer to save time on boatbuilding. Since purchasing this accursed contraption, I have spent more time and money fiddling with it than I have with my ships. It's time I throw in the towel. hang up the keys. decommision the device. Perhaps I will try a different device when I return from my next deployment.