Calibration Situation Rostock Max

[noddynomolos]

I have a version 1 Rambo with the 1/8 stepper.. I am using your older version on the Marlin for Rostock with a Phebe 1 and a plexiglass top glass (well had till this evening).
I have a dial indicator that I mounted on the side of the platform (better than using a finger )
I go through the 4 measuring position ( 1) center 2) y110; 3) x70 y-30 4) x-70 y-30 and get the Z, Y and X spot on. However, when I recheck the center measurement it has dropped. I repeated the process several times and each time the hot end gets further away from the build platform. I re adjust the z, y and x and recheck the center only to find it has moved again.. The amount is a out by about .40 of a mm each time.
Next I adjusted the z= 0 using the paper method (till I could feel the resistance) on the center. Next I did z, y and x. The hotend was way lower at the y and x calibration coordinates.. The center gap at z=0 is about 2 to 2 and 1/2 mm off the hot bed touch's the hotbed at the x70 y-30 coordinate and can not be z=0ed at the x-70 y-30 coordinate it reads (in Repatier as sitting at z 1.3).
I thought that maybe I was seeing things so I tried a print and had the hotend dig right into the plexiglass.
Man I fear I'm gonna bust the whole thing off the build platform or strip the stepper belt..
Any suggestions would be greatly appreciated

[daftscience]

There is a firmware variable called DELTA_RADIUS in the firmware where you can adjust for that. I can't find it right now, but there are instructions somewhere no the forum for bed leveling that includes this.

Edit: Found it

http://forum.seemecnc.com/viewtopic.php?f=54&t=1174

[noddynomolos]

I had a quick read of the thread you suggested. Looks very promising! Cheers!!

[noddynomolos]

Have tightened all belt pulleys and belts ( as suggested by John O) and have followed calibration instructions. I have not adjusted the Delta Radius, however. What I did:
1) Measured bed centre height using m114 and adjusted the firmware. Retested three more times to make sure z= 0
2) measured and corrected each tower z, x and y (using paper method)
3) rechecked centre only to find it had moved (gap increased .4 or .6) yet showed z=0 (m114)
So I did a test block anyway and yes it turned out very dodgy....
Any ideas on why the centre height would change? Is this an issue that I need to change my Delta Radius settings for?
I thought I would have some fun and try a print, a toy from my son's fav computer game 'minecraft'.
In the image you can see the infill is not touching the inner walls; the corners are not square ( especially in the first few layers ); blob like artifacts on some of the vertical surfaces.. He liked it anyway

[noddynomolos]

http://www.flickr.com/photos/94291182@N02/8580892673/

[mhackney]

@noddynomolos - from the photos and your descriptions it sounds like you have at least two issues. You should tackle these independently and in this order:

1) Infill gaps - lots of factors can contribute to this like backlash. But the nature of your gaps leads me to suspect your delta arm joints are too tight or do not move smoothly. See my post Don't Get those Delta Arm Blues that shows how I diagnosed, tested, corrected and verified the problem. In any case, you should close this gap (pun intended) before moving to the next item. Since you will need to remove and sand the arms, it does not make sense to spend more time on calibration until you have this worked out.

2) Once the above is done, set your Z as you describe. The issue you describe with x=y=z=0 being off really seems to be the DELTA_RADIUS calibration issue. It is common and quite easy to correct. The info for this is in the firmware comments or search the build forum.

Let us know how you make out on 1.

[noddynomolos]

Cheers, I will roll up my sleeves and dive into this tomorrow... Thanks for taking the time to look at my pictures and offering your suggestions. I have also enjoyed your Blog... Although, my wife threatened me with bodily injury when I grabbed her nail polish remover and an old nail polish bottle to make your glue recipe with... Guess I will have to source some bottles here in Vancouver
I expect to be ordering an onyx bed soon. Does your aluminium plate cover the new onyx?
Do you use tempered glass on top of your plate? I guess plexi would just melt away at 100c.
Bye for now,
Yours,
Don S.

[mhackney]

Yes, the plate works with both the original and new Onyx. I do use the borosilicate glass I got from SeeMeCNC but primarily because I already had it when I made the plate! You can print to the aluminum or tape put on the aluminum. Plexi is fine, but print at 80°C, 100° is not necessary.

[noddynomolos]

Dear Michael et al,
I have been working away and have pulled apart the universal joints, filed and greased em up real good
However, still seem to be having the issues. 1) print head impacts hotbed as it runs up past the x tower. See picture at http://m.flickr.com/#/photos/94291182@N02/8620597699/
I also uploaded a video to my flickr page that shows the issue in real time. I have calibrated the head using the paper method. I tried changing the Delta Radius to -1 (as you had done). But to no a avail..
Any suggestions would be greatly appreciated... Cheers!!
Don
Ps have you stopped producing your build plates Michael? I just ordered an onyx and went to your site to order one of your 'snappy' plates and found that you had discontinued production.. Guess I will just have to make one here... Bye for now D

[MorbidSlowBurn]

When you did your calibration, did you have you heated bed at temperature? From your first post you said you are printing on plexi, it may warp at temp and can affect the zeroing process. Also take a straight edge and verify that the plexi is flat in all directions (when heated).

Also when you adjusted your delta arms did you adjust the pin to arm interface? Mhackney just added notes about it to his delta arm blues post.

[noddynomolos]

Hi Morbid,
Thanks for taking time to reply.
I will check out Michaels post.
I have updated my build surface from plexiglass to tempered glass(forgot to say that in last post).
So I don't think it's a problem with the Phebe. I still suspect the x tower. Possibly some slippage on the pulley (why make those out of alloy? Brass is so much more reliably). The photos are all taken from the X tower or between the x and y tower. You can see the relative thickness of the plastic extrusion that the hotend is firmly against the hotbed.. Hard enough to occlude the hotend and prevent plastic from being deposited. The pictures of the green tape I had actually left a gap when I calibrated the x coordinates. Further to get Z zero I have the distance set at 371.4.
Bye for now
Don

[[email protected]]

i had the same problem you had and about went crazy before i called seemecnc
I had to change the delta smooth bar offset I added 0.1 and releveled the bed you might have to do this many times before its perfect but adjust 0.1 at a time and recheck.
Also at if you changed your steps to 106.67 there is a number at the end of those that in mine was 284 and i changed it to 584 and my prints started looking a ton better.

[[email protected]]

also i have mhackney's aluminum build plate and its awesome I spray it with hairspray and print right on the aluminum plate with no problems

[cambo3d]

what is this delta smooth bar offset?

[[email protected]]

it is how you adjust for dip or bow in the middle of the bed
i would get the xy and z rails calibrated perfect then go back to the middle and it would be too high
just like op's problem so i called seeme and they told me about smooth bar offset and it fixed my problem
Im not the best at trying to explain how it works I just know it fixed the problem. I had been running in circles for a month
with that problem and finally called them and in ten minutes had my answer and wish i had called them much sooner (like a month sooner)

[Eaglezsoar]

i had the same problem you had and about went crazy before i called seemecnc
I had to change the delta smooth bar offset I added 0.1 and releveled the bed you might have to do this many times before its perfect but adjust 0.1 at a time and recheck.
Also at if you changed your steps to 106.67 there is a number at the end of those that in mine was 284 and i changed it to 584 and my prints started looking a ton better.

Are you using the repetier firmware or marlin?

Carl

[Polygonhell]

The smooth bar offset is just one of the many values used to compute delta radius.
There are only two values that affect the print, the length of the arms which affects the XY scale, and the horizontal distance from pivot to pivot when the extruder is in the center of the build plate, called DELTA_RADIUS in the firmware which affects doming.
The math is really simple it's just Pythagoras.

[noddynomolos]

Thanks for the ideas guys,
I must admit I was feeling a bit lost.. As my prints look a real mess!! My last test block looks like an ancient Egyptian ruin Kinda artistic but not what I was trying to achieve.. http://m.flickr.com/#/photos/94291182@N02/8629098332/ Further, if you click on the short video just before ( on my Flickr album) you will see the bowing of the print and also how the print head is pulling the print off the glass. Grrrr
I have ordered an onyx bed that is due to arrive next Wed.. I am excited to install it. Sadly, I could not order one of Michaels beds.. Guess I will fabricate one myself.. I ordered the borosilicate glass as well so that should help.
All your suggestions and encouragement are much apreciated. Cheers!
Don

[[email protected]]

im using Marlin-for-rostockmax-ramboLCD-master


and all i know is the smooth bar offset fixed my doming problem which is what john and steve told me to do and it worked

[noddynomolos]

here is my latest pring using hairspray on the glass http://www.flickr.com/photos/94291182@N02/8629796411/ Stopped it after only 5 or so layers as it was getting caught on the print head...
ps how do you add photos on to this forum? I tried pasting the URL between the img html script but no go... I can't seem to copy past the picture from my computer either..

[noddynomolos]

http://www.flickr.com/photos/94291182@N02/8630904422 after I stopped the print

[Polygonhell]

I would say your bottom layer is too high which is why it didn't adhere. The skirt should be even and it's edges should touch each other, when the extrusion going down on the first layer looks rounded it's generally too high.
What plastic is it, what bed temperature are you running, what hotend temperature?

[noddynomolos]

1.75 ABS from a local supplier (probably from China). Extruder temp 210C; Bed Temp: 80C; tempered glass with hairspray; speed 10mm; layer height 3 on bottom and 2 for rest. John Olie kindly replied to my last e-mail in which he suggests I am printing to fast and maybe too hot. He goes on to suggest (as you did ) that my layer height is too high.
Am using the Rostock build (Johns build) of Marlin for my older Rambo 1.0
In Repatier ( Latest version) when I set up slic3r I set the speed values to 10mm ( as Michael had suggested on another thread). How else could I adjust the print speed temps etc?
I have pulled all the arms off and sanded and lubed all the joints (smooth as a babies bottom ). I have also pulled all the belts off and re tightened all the belt pulleys.
Bye for now
Don