I had always heard about the LW PLA filaments and how much weight you can save, but one of the things that discouraged me from trying it was the cost. The most common LW PLA runs about $50 for a 700g roll which makes it rather expensive even though it goes further than standard PLA.
When 3dLabPrint released their new PolyLight LW PLA at the same price but a full 1kg spool I decided to give it a try. First off I love the color they picked, a light grey is easy to paint whatever color you want, and for the model I want to print (the MIG) it actually won’t need to be painted and still will look very good.
So first things first I did the first test of printing various cubes at different temperatures to see what temperature gave me the greatest expansion. It turns out that for my printer (a BIQU B1) it’s at 260 which is also the upper limit on the temperature for this printers nozzle. I then printed various cubes at different flow rates from 90% all the way down to 30%. During this testing I found that 40% was spot on based on the tests.
So for the first ‘real’ print I went ahead and printed a benchy. It had lots of stringing (which I was expecting, I basically used my normal PLA profile and just changed the temp and flow rate) and holy cow I couldn’t believe how light it was and it still had excellent strength.
So now on to a standard plane part. I decided to print the wing tip from the easymax, as it’s a nice quick print and it should tell me what I want to know, basically are there any issues printing with the LW PLA. The first print I did with the standard internal support didn’t come out that great. About half way through it started having trouble because of the retractions. So for the second attempt I went ahead and turned off all retraction.
That made a huge difference and the wingtip printed out just fine with all the structures. Only thing was it was extremely flexible, like silly flexing when I pulled it off the bed.
So for the third attempt I increased the flow rate up to 50% and while it did improve the stiffness a little bit, there was still way to much flexibility. Now the surface of the print looked fine (except for the stringing which was easily sanded/cut off) and the layer adhesion was very good.
For the fourth attempt I turned on the infill to about 15% just plane cubic infill and that came out awesome. The part printed in regular PLA weighs 17.5 g and the one in PolyLight weighs 5.65 about 70% lighter than a standard PLA part and it was stiffer than the other attempts.
Glueing the parts together worked very well too, nice solid glue joints and I imagine the foamy structure helps the glue get absorbed a bit more than standard PLA.
I’m super happy with the filament and I’m really looking forward to printing an entire plane now and seeing how it comes out.
Here’s a few pictures of the prints: Picture Gallery