Successful First Print and Leveling Questions

[benglish]

Hi!

I just completed assembly of a Rostock Max. It's my first delta printer. I've attached a picture of my first real print (after 1 test cube). I was surprised at how well it printed right off the bat, especially after the time consuming assembly process. Now that I've gotten that out of the way, I'm refining the calibration of the printer. This is where I need your help. I think I've gotten the "Printer Radius" value pretty close but I am running into a weird problem:

The nozzle is at the same height at the base of each tower and the center of the build area, but is raised up slightly in the areas between each tower. This is especially noticeable at the limits of the build area (IE: when making a large radius circle). I've been using the Rostock Onyx Bed leveling Aid from thingiverse to help visualize this effect. I could get out the dial indicator, but that's overkill at this point. Any thoughts? END_EFFECTOR_HORIZONTAL_OFFSET, CARRIAGE_HORIZONTAL_OFFSET, PRINTER_RADIUS all are summed (-) to give DELTA_RADIUS, so I suspect that altering those won't fix the problem (as I've played with the delta radius values a bit...maybe I need to do more?) .

Using the 0.83 Repeiter Firmware from See Me Cnc

Any help would be greatly appreciated!

Thanks!

+Blake

[626Pilot]

PRINTER_RADIUS is the setting. There is a section about that in the assembly manual. I recommend getting the dial gauge and printing a holder for it. Makes it a lot easier for the initial setup.

[chosenken]

I'm also facing the same issue, need to investigate this.

Could you suggest a holder? I'm searching Thingiverse and not finding anything that will work for a Rostock.

[geneb]

You don't need a dial gauge to calibrate the machine.

g.

[Eaglezsoar]

I'm also facing the same issue, need to investigate this.

Could you suggest a holder? I'm searching Thingiverse and not finding anything that will work for a Rostock.

I couldn't find one on Thingiverse either.
This is one for the Rostock Max sold by Trick Laser: http://tricklaser.com/Pen-Tool-holder-f ... RM-PTH.htm
SeeMeCNC sells the Pen Holder also, but like a lot of things, I couldn't find it on their website. Since they redid their site
there are a lot of parts and such that are hard to find or do not exist.

[626Pilot]

You don't need a dial gauge to calibrate the machine.

You don't need half the things in your house but you keep them anyway because they make life easier.

[geneb]

A dial gauge in this case doesn't make your life easier.

g.

[626Pilot]

A dial gauge in this case doesn't make your life easier.

It made my life easier in several ways. Today, I can do without it. I have enough prior experience to fall back on that I can confidently rely on my intuition to tell me when an endstop screw is Good Enough, and how many degrees to rotate it if I notice a certain phenomenon, and what subtle movements to make with a screwdriver to bump it by just a degree or two. For me to be good at this, I had to work very hard on building that skillset, because before the Rostock I had never done anything remotely close to building and calibrating complex machinery. I had no innate sense of how accurate I could expect the machine to be, or how much tweaking one particular variable would help or hinder that accuracy, let alone all the subtleties of how the whole system works together. So while I had a general idea, there was a lot of knowledge and theory that I had to tighten down.

Using a dial gauge was a big help. It took a lot of the unknowns out of the system. Instead of trying to remember how close the friction from one tower resembled the friction from the other two across the minute or so it would take to measure all three, I could simply read the elevation accurate to about one thou. Moreover, I could observe that turning the screw 1/8 turn would move the elevation by precisely this much, and 1/2 turn by precisely that much. I kept track of it in a text file and considered the effects of different degrees of rotation. That let me figure out the slope of the equation.

I could have achieved the same effect with paper, but it would have taken longer to calibrate my senses to the task, to the point that the extra five minutes spent mounting and dismounting the dial gauge paid off quite well. Because I had more confidence in what I was doing, my level of apprehension about how hard it was going to be (based on my difficulty assembling the printer) was reduced and the whole experience became less irritating and more rewarding.