Problem with fist layer above Raft

[mash3d]

So I'm trying to figure out why I'm having an issue with the first layer above a raft.
I did a search through the forum but did not see anything that stood out as addressing this specific issue.
The top of the the raft is fine but the first layer of the actual model is a mess.
The rest of the model prints ok.
I'm printing with a raft to avoid elephant foot issues
If any one has any suggestions I would appreciate it.
My Settings are below the images

Raft_Example by michael32766, on Flickr

Part_Bottom by michael32766, on Flickr

Part_Top by michael32766, on Flickr

Cr10S printer with Inland Grey PLA
Extruder tab:
nozzle Diameter: 0.40
Extrusion Multiplier: 0.98
Extrusion Width 0.40
Retraction on;
Retraction distance: 6.00
Extra restart distance: -0.10
Vertical Lift: 0.00
Coast and end: ON
Coasting distance: 70.0
Wipe Nozzle: OFF

Layer Tab
Height: 0.100
Top Solid layers: 6
Bottom Solid layers: 6
Outline Shells: 2
First layer Height: 80%
First layer width: 100%
First layer speed: 50%
Start points: Optimize for fastest speed

Additions:
Use brim: OFF
Use Raft: ON
Raft Top Layer: 2
Raft base layer: 2
Raft offset from part: 1.00
Separation distance: 0.30
Raft Top infill: 100%
Above Raft Top Speed: 30%
Prime Pillar: OFF
Ooze Shield: OFF

Infill Tab:
Fill pattern: Fast honeycomb
External Fill pattern Rectilinear
Interior infill Percentage: 50%
Outline overlap: 75%
Infill Extrusion width: 110%
Minimum infill length: 0.50
Combine infill every: 1 layer
Internal infill Angle offsets: 0
External infill angle offsets: 45 / -45

Support Tab
Support infill percentage: 10%
Extra inflation distance: 1.40 mm
Support base layers: 1
Combine support Every: 1 layers
Dense support layers: 0
Dense support infill percentage: 70%
Support resolution: 5.00 mm
max overhang angle: 45 Deg
Separation from part
Horizontal offset from part: 0.40 mm
Upper Vertical separation layers; 1
Lower Vertical separation layers: 1

Temperature tab:
Bed: 50
Extruder: 200

Cooling:
Layer 1: 0
Layer 3: 30
Layer 4: 60
Layer 5: 100

Speeds:
Default Printing speed: 50.0 mm/s
Outline under speed: 50 %
Solid infill under speed: 50 %
Support structure under speed: 80%
X/Y Axis movement speed: 80.0 mm/s
Z axis movement speed: 16.7 mm/s
Adjust printing speed for layers below: 15.0 sec
Allow speed reduction down to: 20%

Other Tab:
Unsupported area threshold: 25.00 sq mm
Extra inflation distance: 0.00 mm
Bridging extrusion multiplier: 90%
Bridging speed multiplier: 140%
Tool change retraction distance: 12.00 mm
tool change extra restart distance: -0.50 mm
Tool Change retraction Speed: 10.0 mm

Advanced Tab:
Thin wall behavior:
External thing wall type: Allow single extrusion walls
Internal thin wall type: Allow Gap Fill
Allowed perimeter gap: 75%

Single extrusions
Minimum extrusion length: 1.00 mm
Minimum printing width: 50%
Maxim Printing Width 200 %
End Point Extension Distance: 0.20 mm

Ooze control:
Force retraction between layers: ON
Minimum travel for retraction: 2.50 mm
perform retraction during wipe movement: ON
Only wipe extruder for outer-most perimeters: ON
Avoid Crossing Outline for travel movement : ON
maximum allowed detour factor: 3.0

[dkightley]

Firstly, upgrade to v4.0.1 if you're not already on it. Big improvements to rafts were made in either this or the previous release v4.0.0...can't remember which it was.


The separation distance should be a lot smaller. I use 0.01 to 0.03 depending on the extrusion multiplier I have. For 0.98, I would suggest 0.03....but you need to try a value and adjust accordingly. And reduce the raft top layer percentage down to around 50%.

[mash3d]

Hi, Thanks for the reply, I did do the upgrade to 4.0.1 and set the raft top layer down to 50%.
I tried adjusting the separation distance down to 0.03 but the raft would not come off.
The smallest I was able set it to and have it come off was 0.25 mm.
Thanks,
Michael

[Inschenieur]

if you increase cooling or decrease extruder temperature (or increase above raft speed) the part comes off easier at low separation distances. you want to try to reduce adhesion of the bottom layer on the raft as much as possible.