Sunday, July 10, 2011

Mendel frame takes shape...

I had a major crash of the Rapman 3.0 printer and for several hours I thought I was really knackered. One of the leads to a phase of the extruder stepper parted because of fatigue from thousands of hours of vibration. The system shut down and reset. At first I thought I had a simple static discharge event, the first in many months. I fired the system back up and discovered that the extruder stepper would dance around but wouldn't pump filament.

After serious prayers that the stepper driver chip for the extruder hadn't fried I rewired the connector and got the extruder pumping ABS again only to discover that the intense vibration from the stepper before the reset had actually shaken apart the Arcol extruder hot end that I had bought from László Krekács in Hungary.

This sounds worse than it was. I simply screwed it all back together and cleaned the extruder end and it worked perfectly again. Unfortunately, I will have to recalibrate Rapman now. That should take a few hours that I didn't have available today.

In any case, I was able to cobble the Prusa Mendel frame together this morning.

It's a dinky little thing, but interesting all the same.


Marcus Wolschon said...

Sounds like bad luck with your RepMan.
Any details on that "Arcol extruder"?

Forrest Higgs said...

@Marcus You didn't know about Laszlo's Rapman hot end replacement?

I've been using a 0.5 mm orifice one with no complaints since my last BfB one blew up months ago. The stepper failure shook it apart but didn't ruin it.

Marcus Wolschon said...

Not until now.
I was busy getting my new Thing-o-Matic to be reliable and was not paying attention to the RepMan -forum for a while.
Now I'm thinking of their 0.35mm hot-end for my dual-extruder-upgrade.
But I guess I need to wait for him to get new Thermistors.
I have one spare here but that is already reserved to meassure the temperature of the heated platform using the extruder#3 -connector.

Bogdan Kecman said...

You can get 0.35mm from laszlo, they work great (and he is way faster to respond to emails then BFB)

Marcus Wolschon said...

First the dual-extruder upgrade and then new threaded-rods, a thicker heated platform and a thermistor+relay to control the platform-temperature.
One step at a time. :)

Is Laszlo the one doing