Yes, ABS shrinks quite a bit when cool down. But from 60°C (chamber temp) to 25° (room temp) it isn’t much
@Leojoy , I don’t bother change default shrinkage of bambu ABS, I do change the bed temperature though. For that small print (35mm long) shrinkage is almost neglectable.
But if you print something big like 150-200mm long, it could be 1-2mm shorter depend on how dense you want your print
I agree with @duane777 , I use 0.5% as shrinkage for compensation sometime up to 1% if I want the part printed solid (80% infill, 4 layer walls…). I scale the part in fusion360 before sending to the slicer instead of using slicer to scale the part. I only do this for the part I need accuracy
It should allow it to shrink back to the size you need it be. I only do it when I need my part to mate with no printed parts. I has a look a the gcode to make sure what it was doing, ie when you slice it scales x&y before slicing in memory - it does not change the part’s size on the plate. If that makes sense.
There is no hard compensated value, you have to try and measure it yourself. Like, print something 200mm long, then measure it after print and work out the the compensation ratio.
I don’t use BBL filament so I cannot comment on the filament people usually use. It’s expensive for me since I have to pay extra AU$15 for shipping on top of AU$50 for a BBL ABS roll. Usually, I can get a deal from ebay for sunlu ABS around AU$17.
Another note: ABS is mixed from 3 monomers acrylonitrile, butadiene, and styrene, so that different ratios will have different properties. And so softening temperature varies from 90°C to 110°C depends on mixing ratio as well.
same with me… I just use the bambulab abs setting, but I use sunlu abs filament for my printing. bambulab filament way to expensive for my small business, even though sometimes I just want to buy one spool to try and “taste” the original filemant for bambulab.
so far, with 100% shrinkage setting, all my puzzle plates seems can connect each other without problem and have the same size.
with sunlu filemant, 100 degree celcius in the minimum bed temp, I ever tried 90 and 95 degree… and always get first layer problem and can’t stick on bed proper. even that, is never without a problem as I mention at my first post. the failure always can be exist. from the corner warping, brim not stick on bed or the whole object just not stick on the bed and create undesired spaghetti… until now, I still tried to find the good setting from many youtube “expert”…
For anyone using it, I found that Eryone ASA from Amazon works well with a bed temp of 110C, and using brims really helps.
For dimensional accuracy, I used the model mentioned earlier, and found I needed to set the shrinkage in the filament settings to 99.3%, and the calibration model comes out exactly the correct size.