Actual dimensions don't match design

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daveinhull
Posts: 66
Joined: Fri Jan 11, 2013 2:31 am

Actual dimensions don't match design

Post by daveinhull »

Hi,

I haven't been on the forum for a while due to work but just last week I needed to do some more 3D printing - printer worked first time since February :)

I've updated the firmware and the host S/W.

However, I notice that the printer size didn't match the design size so I created a small test piece, see attachment
The dimensions are 1mm wide, 10mm high and 19mm across the X.

When it prints I get 1.1 to 1.36mm wide thickness, 6.75 to 6.84mm high and 18.85/19.2mm across the X

The main problem is with the height.

I used the SFACT 4_4_Production, no support, normal fill and Creo Elements/Direct Modeling Express to create the .STL file.

Can someone give me a few pointer to what might be wrong?

P.S. I like the new V2 z-axis and I'm thinking of buying the upgrade but just a little fearful of the amount of work involved - anyone done it, how long did it take and was it quite straight forward - it looks like you pretty well have to dismantle the whole printer?

Many thanks
Dave
Attachments
Test 2.jpg

seaton
Posts: 291
Joined: Tue May 14, 2013 9:04 am
Location: Bunbury, Western Australia
Contact:

Post by seaton »

have you performed a full calibration so that steps/mm on the x, y, z and Extruder measure correctly? There are plenty of tutorials out there, use a large value such as 100mm or greater when calibrating. You need to do this first then do a thin wall test, i.e. extrude the test object you can download from the main downloads of this site. It's a test where the actual extrusion wide on the printed wall should match the value thats set for width of extrusion in your slicer. once all these are right then you will find your measurements will be fine. If not then there might be something else wrong mechanically, i.e. slipping extruder etc.

When I'm doing it I put the calculated steps/mm in my start gcode until I'm happy then I put them in my firmware (don't use my values below as I have a Y Axis belt problem and will not be right on your machine)

G28 ; home all axes
M92 X76.68545427285747 ; calibrate X
M92 Y68.45667692990979 ; calibrate Y
M92 Z1601.87731 ; calibrate Z
M92 E150.3 ; calibrate E
Last edited by seaton on Sun Jul 21, 2013 3:51 pm, edited 1 time in total.
Stephen...

Felix 2.0 -> Felix 3.0 dual
Simplify3D Slicer, Kisslicer
Have you added your Felix to the Map? http://goo.gl/maps/HajnZ

http://blog.strobotics.com.au

daveinhull
Posts: 66
Joined: Fri Jan 11, 2013 2:31 am

Post by daveinhull »

Hi seaton.

Thanks for the quick reply and I'll give it a go......

Dave

dognotdog
Posts: 181
Joined: Tue Sep 04, 2012 9:22 pm

Post by dognotdog »

The Z height is close to what you'd get if the steps/mm for the Z axis were for the 2.0 acme threaded rod, but you still have an M8 threaded rod in there. Thickness seems to be within normal variation accounted for by the slicer, check your extruder and slicing settings.

The XY values are just approximate, the steps/mm there do depend on belt tension, so you might need to periodically readjust those as suggested in the previous post.

daveinhull
Posts: 66
Joined: Fri Jan 11, 2013 2:31 am

Post by daveinhull »

Hi dognotdog,

Yup you got it - I foolishly installed the V2 firmware thinking it was just a general update (should have read a bit closer :oops:)

Re-installed the original firmware and all working perfectly :)

Thanks guys,

Dave

superhornet59
Posts: 60
Joined: Wed Apr 03, 2013 1:58 am

Post by superhornet59 »

Seaton, how do you modify the steps/mm in the firmware?

seaton
Posts: 291
Joined: Tue May 14, 2013 9:04 am
Location: Bunbury, Western Australia
Contact:

Post by seaton »

superhornet59 wrote:Seaton, how do you modify the steps/mm in the firmware?
You can do it through the EEPROM settings from within Repeiter host (which doesn't seem to work on my MAC), however once I'm happy with them I like to update my firmware source with the values and I re-upload to my control board. That way everything is uptodate

I update the configuration.h file in the firmware source you should see a line like below #define DEFAULT_AXIS_STEPS_PER_UNIT the values are {X,Y, Z,E}

// default settings

#define DEFAULT_AXIS_STEPS_PER_UNIT {76.4484265051051, 75.23938373275558, 1601.87731, 150.3} // default steps per unit for Felix 2.0
#define DEFAULT_MAX_FEEDRATE {500, 500, 5, 45} // (mm/sec)
#define DEFAULT_MAX_ACCELERATION {5000,5000,100,80000} // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for skeinforge 40+, for older versions raise them a lot.


However if you update it and re-upload source it won't come into effect as you will have values stored in your EEPROM, I increment the EEPROM_VERSION value "configurationStore.cpp" (or you can do a restore factory settings from LCD menu) compile and then upload to my board

// IMPORTANT: Whenever there are changes made to the variables stored in EEPROM
// in the functions below, also increment the version number. This makes sure that
// the default values are used whenever there is a change to the data, to prevent
// wrong data being written to the variables.
// ALSO: always make sure the variables in the Store and retrieve sections are in the same order.
#define EEPROM_VERSION "V10"
Stephen...

Felix 2.0 -> Felix 3.0 dual
Simplify3D Slicer, Kisslicer
Have you added your Felix to the Map? http://goo.gl/maps/HajnZ

http://blog.strobotics.com.au

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