I have some bambu silk filament. I have been working with this roll for over two weeks now trying to get a decent result. Using cheaper silk I don’t seem to have these issues. Here is what I have done:
Drying: This roll has seem more drying time in my sunlu than any other filament. Probably had over 20 hours or more.
Calibration: tried bambu stock settings and adjusting flow. Also have set my own k value twice and adjusted flow there.
Temperature: Temp tower was done.
I have tried every temperature from 210c all the way up to 240c. Bed temps as well. No matter what I do I cannot get this filament to NOT either warp and wrinkle, or get little zits all of it.
These are not seams as you will see. I’ve now printed numerous blocks with different flow rates, k values and temperatures. With high heat I get close to removing the zits, and they slowly start to become wrinkles. I’ve tried wall order as I know that has effected wrinkling for me in the past.
I am using blocks so the layer time is consistent throughout.
Wet filament can cause these zits… was this stuff just so water logged out of the box that it is ruined? You will see in the images that the zit volume lowers (this is caused by temperature) but I can’t tune it out. Higher temps slightly less zits, but then causes wrinkles.
Printer: A1 mini.
Speed: Accelerations all reduced to 300. Print speed reduced to 40/30.
NO issues with geeetech cheap silk. Anyone have an idea?
Here is extreme wrinkling compared to the cheap silk on an actual model:
The filament barely extrudes as you will see in one of the images.
Try reducing your retraction length and/or increasing the retraction/deretraction speeds. As a test, give it 0.4mm retraction. Silk puffs slightly in an elastic manner when molten, does real odd things inside the nozzle. If you had an x-ray for the nozzle during retraction, youd see molten plastic still clinging on the walls and an air gap in the middle. Silk puffs, can close that air gap into a literal bubble that gets blown out next extrusion. Can be very touchy.
It is rare (to me) but possible to have a spool get ruined by $manyEnvironmentalFactors. In my experience, they become overly brittle.
I will give that a shot, should I expect to see more or less of the blisters as I increase retraction?
If its not moisture/something else, then you should see them eliminated. With lower retraction though, you might find stringing on long travels coming back, and now you’re in the delicate balance of how far to push one parameter to perfect another 
You can try the values between 0.4mm and the default 0.8mm for a better fit / correct threshhold, you could travel faster, but now you might shake the model too much, and for that you can add brims, but that might blah blah blah
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Awesome, once i’m done with this print i’ll give it a go and let ya know! Thanks. There is definitely something up with this filament though… its like it has too much starch in it. It’s super thick n pasty compared to other silk.
I have read people having issues with the bambu on here so I guess perhaps it happens.
I just got a new spool of Bambu silk PLA and it is having the same issues. The spool I had two years ago printed much better. I think they have changed suppliers/formula.
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Hmm… mine is from bestbuy and they don’t have a wide selection so i’m assuming its a newer one. It’s a shame because I love the color combo. Can’t find the same style without it being tri color… unless its a super expensive brand.
Brand new 14 dollar roll of Geetech off amazon… zero zits or wrinkles even in a big project… it is without a doubt the bambu filament.
I gave it another 26 hours of drying just for the heck of it. (my place is around 22% humidity with the heat on)
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