Hoping to get some help from some of you that have experience printing with PA6-GF. This was my first attempt printing with it and the result is pretty bad. The finish on the part is very rough and very uneven in some places. I am pretty sure this has to due with the filament being to humid but I did leave it on the print bed at 80°C for about 30 hours turning it over half way in. This should have been enough time to dry it out right? or does it need to dried for longer? or maybe in an oven?
This was printed on X1C with the default profile for PA6-GF with a 0.6 hardened steel nozzle. The chamber was heated up to about 50°C before starting the print and during the hole 6 hour print the door was never opened and the inside temperature was always around 50°C.
Once the spool was finished drying it went straight into the AMS and started the print after the half hour heating of the chamber.
The side with the worst finish was the side facing the glass door. Could this have causes this side to have a worse finish or was this just coincidence? I have seem some posts and videos where people print PA6-CF on the X1 without extra isolation without any issue so I am thinking this is just a coincidence or is PA6-GF harder to print?
The thin bands that you see running along the part is what the finish should look like on the hole part so the conclusion that I cam up with is that the band with the correct finish was created when the filament was being pulled from the side of the spool that was facing down during the last hours of the drying process further indicating that the drying did almost nothing for the drying of the complete spool…
I think I did everything correctly but the result was not what it should have been. Any tips on what I should change or do different for my next test print?
Also looking into buying a filament dryer and want it to work well for this filament as there might be many future prints with this filament but I have read some post saying that the best to dry this filament is 80°c or even 90°C and since almost all dryers only go up to 70°C I don’t know which I should buy. Will 70°C max temp. over a longer period be ok for this filament?
Yeah one side of the spool was more dry than the other. If you want to dry PA regularly, you should definitely get a filament dryer. 70 max will be OK, it just takes longer than 80 or 90, but if you do a long initial dry and print from the dryer, it’s not so bad. You could also get an air fryer or food dehydrator if you want the higher temp and not compromise on the drying time.
Thanks for the help and the advice. I was thinking of the mini kitchen ovens or mini pizza ovens. There are some that go as low as 60°C but then I would still have a problem when printing. I would have to print from the AMS and since this filament apparently is very complicated when it comes to moisture, this might be a problem for longer prints. I guess the safer option is to just get a normal filament dryer that goes up to 70°C and just leave it for longer.
Yes I’ve done it with a normal dryer at 70 and printed while drying. If I recall correctly, I did like 24 hours at 70 before starting the print. What you can do is test the “dryness” by extruding in the air and seeing if a puff of steam comes out from the just-extruded filament just before your actual print. And of course, observing the first few layers. (You can also measure the weight but if you print from a dryer, you just care about drying the outer layers of your spool)
Thanks again for the advice. I didn’t think of checking for signs of humidity when the filament is being extruded. Will definitely be looking out for this next print. I presume it will also create bubbles on the string of filament if it is to humid?
Yeah, the bubbles will be super obvious! They make popping noises too. The extrusion should just be a straight line straight down. They appear within like an hour of PA being in the atmosphere (depends on where you are of course).
it’s wet. it needs convection/blast drying and 70°C isn’t hot enough. no matter how long you dry it at 70°C, if you weigh it and then dry it at 80° or 85°C you will find additional grams of moisture are removed and then it will print properly.
yes, we’ve all seen the my tech fun video, but no, no amount of time at 70°C will dry the PA6-GF properly. 80°C+ and you will have success. this has been discussed many times on this forum.
a convection lab oven rather than a filament dryer is the best choice for these filaments that require high temp dehydration. the lab oven will also be able to properly anneal your parts which the filament dryer can’t do either.
Yeah that would be great if it wasn’t for the price of one. But even with a lab oven that will still leave the problem of printing. I would still need a filament dryer to maintain the filament dry during longer prints right?
you can print the PA6-GF from the AMS and that should be fine for a 6 hour job with freshly dried filament. but even with a full dessicant pod upgrade in the AMS the PA6-GF will absorb moisture and start printing funky again after a few days or a week depending on your RH. it wants the water as much or more than the silica gel does.
