My z height was off from the factory also. tisk tisk!

You mean the z zero height or the actual steps per mm? as mine have all been spot on.

Or maybe some big goof hit a wrong button.

You pick.

My z height was off from the factory also. tisk tisk!

No calibration on this machine can survive a bouncy trip on UPS trucks for vast distances. It should come with a note saying that :-).

Tried to print out some coins for testing purposes, but they were a little blobby yet, not quite sure why.

What is the optimum temp for printing ABS?  I've tried 285-205 with bed at 100.

Ok, I understand some of what is going on on that page. He's not talking about the volume change at the pinching of the filament with the hobbed gear, but rather in the actual part you produce. I guess this also makes the most difference in parts with a large surface area to the volume ratio. Interestingly it means my method of relying on a 0.42 or 0.5mm one-wall object for calibration can be a little flawed.

But to un-derail,

gwfami, where are you right now? Has calibrating helped?

IanJohnson wrote:

PLA and ABS will need different extrusion multipliers.  Extrusion Multiplier is a fudge factor to adjust for how much the gear teeth compress the filament as it feeds.  PLA is harder than ABS and usually takes a higher multiplier.

Eh? Are you suggesting that the effective radius of the "hobbed bolt" is changed depending on how deep the geared tooth digs in? I feel it highly unlikely, the difference between the min diameter and tooth max diameter is a low percentage of the total diameter....Isn't the extrusion multiplier just a fudgefactor for the measurement of the filament and your Extruder steps calibration?

It's different between all filaments for me, partly out of difficulty measuring the radius of the filament.

Here is an explanation - http://hydraraptor.blogspot.nl/2011/03/ … -rate.html

It's the effective difference in gear radius, and also the change in volume of the filament from the teeth marks.

If I have a bad batch of filament, which may well be the case, where company provides the best consistent filament?  I've been looking at the filament reviews and they are all over the place.

The bad filament I have seen basically won't adhere to itself causing the layers to flake apart.

There are so many good suppliers out there. I have used Maker Geeks and Octave with good success. The best way to ensure quality is to make it yourself. Check out http://Filastruder.com and http://osprintingllc.com/ . It will also save you a bundle of cash if you plan on printing a lot.