Reduced Edge First Layer

[mark@ohmnilabs]

To create good adhesion and surface finish, the first layer of my prints flatten out a bit. The flattening causes the first layer to enlarge relative to the upper layers. It would be great to have a feature that acts like an opposite direction brim. This could pull back the outer edge of the part on the first layer to match the above layers, while maintaining the adhesion and surface finish that has been dialed in.

[dorsai3d]

It's not exactly a one click option, but when it's critical, I create an extra process for the first layer using start/stop printing at height. Then I set the horizontal size compensation to shrink the first layer by whatever amount I've measured (usually about ~0.3 mm for me).

[bray.christopher]

Similar to this request: viewtopic.php?f=23&t=5042

[zemlin]

I often put a small chamfer on the face of the part that is against the bed.

[BaronWilliams]

+1

I ran into this issue the other day. Yesterday I had to spend some time post processing a part to remove this 1st layer swell because I forgot to account for it in my model.

On the Gigabot prints I typically get a swell of 0.18mm on the perimeter of the 1st layer when I print a 1st layer at 0.27mm layer height. This also occurs on the other printers I use, but the swell is slightly different, and of course varies depending on layer thickness, leveling, etc.

All we need is a 1st Layer Horizontal Size Compensation setting that's only for the first layer. It would work exactly the same as the current Horizontal Size Compensation setting, but only be applied to the first layer.

An optional check box such as Relative Compensation could make the 1st Layer Horizontal Size Compensation relative to the current Horizontal Size Compensation setting if checked, or be completely independent when not checked. Both relative and independent are useful. If relative, the 1st Layer Horizontal Size Compensation value would simply be added to the Horizontal Size Compensation value when printing the 1st layer. If not relative, the Horizontal Size Compensation value would be ignored for the 1st layer.

[mark@ohmnilabs]

Hi all. Thanks for the replies and sorry I am just getting back to this now. I have tried both adding a 0.5mm chamfer to the parts and adding a process to essentially do a first layer horizontal size compensation. Both have solved the issue but adding a chamfer on all parts is time consuming and does not always apply the same if the part leaves the print surface at an angle.

It would be nice to add a 1st layer horizontal size compensation feature with it's own value, like BaronWilliams suggests. In the meantime, I will just use a separate process for the first layer.