integrate raft layer into model?

here's a proposal: Have the first layer slice thicker, by some multiplier, so that it acts like a raft.

Something like this would be a boon for those printing at very small layer heights, since you wouldn't have to have your bed so incredibly level and finely calibrated.

So for example, Neil could do the first layer at .3mm, and the rest of the model at .01mm.

You may be able to achieve this already, by combining changes to Object First Layer Flow Rate Infill/Perimeter multipliers from Speed plugin and Additional Height Over Layer Thickness in Bottom.

Sounds like what you want is making the head move up more before first layer and multiplying the amount of plastic extruded on first layer.

The only drawback I can imagine is that the object will be a little bit taller than expected (offset would be the difference between normal layers and first layer height).

I'm suggesting the first layer should be carved at a different layer height than the rest of the model. The overall height of the model would stay the same. adjusting the first layer flow rate settings wouldn't change the extruder paths to compensate, either, so you'd get a messy first layer. it would probably work, but not ideally.

the easiest way to test it would be to Frankenstein up some gcode: carve it at both heights, then cut and paste the first layer from the "thick layer" file into the "thin layer" file, and then delete out enough layers from the start of the "thin layer" file to make it the right height. it'd be a chore, but maybe less of a chore than an hour of leveling the bed.

actually the more i think about it the more i'm surprised it hasn't been done already.

Edited 1 time(s). Last edit at 12/30/2011 11:29AM by Buback.

You need to read nopheads' Auto bed leveling blog entry.

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Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
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