What cauises a 3D model in PLA to warp at one end

[Columbo]

What causes a 3D model to warp during printing using PLA? I am printing some fishing lures on my new Creality CR-10S and while some turn out really well, others seem to warp slightly on one end. Most of these lures print in two parts that are later glued together so when one warps on one end it prevents them from gluing together properly. I print almost all of these lures with the same settings which are as follows:

Nozzle: 200
Bed: 60
Infill: 15

For adhesive I am using a glue stick.

I would love to find a solution for this problem.

Thanks

[curious aardvark]

1) up the bed temperature slightly.
65 tends to help.

2) Buy better pla.
cheap pla will warp, good pla pretty much doesn't.

3) get some dimafix and use instead of gluestick. Stuff is great :-)

4) reduce the z-gap so the filament gets smooshed into the printbed.

5) print your first layer slower - what print speeds are you using ?
Good adhesion and release is a combination of print settings, bed material and print speed.

6) get a sheet of pei and stick it over your printbed. filament sticks to it when hot and releases when it cools.

[Columbo]

Thanks curious aardvark, I'll try those suggestions. I am using a speed of 60mm/s and I have checked Z Hop when retracted. Would slowing the speed down to about 50 help?

I am using the filament that came with the CR-10S printer and it doesn't say what brand it is. I also bought some filaments by Mech Solutions and Sunlu. What brand would you suggest?

[curious aardvark]

don't use z-hop. That will actually pull the filament up.
and slow the FIRST layer down to 10mm/s

Actual print speed for the rest of the model can be as fast as you like to maintain the quality you're after.
But for the first layer - the slower you print the better it should stick.

I've printed some models that take an hour or so where the first layer is 50% of the overall print time.

Once the first layer is down you can print as fast as you like.
Also a good idea to have the cooling fan off for the first 2 layers.

sunlu is good filament - never used the others :-)

[Columbo]

I'll try your suggestions. Mech Solutions is a Canadian company that I bought the CR-10S from. ( located in the suburbs of Toronto, Ontario ). I don't know who makes the filament for them.

Thanks for your help. Have a Happy New Year!

[curious aardvark]

and make sure the bed is really well levelled :-)
Bed levelling and getting first layer to stick well, is 90% of getting a successful print :-)

pics seem to show a side mounted filament holder. get it on the top of the frame asap :-)

[Columbo]

I guess I will have to print a couple of mounts to get it on the top of the frame.

Thanks again.

[curious aardvark]

yep always best to make your own :-)

What a top mounted roll of filament does is massively reduce the tension on the filament. At the side the filamen has to go up and then a sharp bend down to the extruder. Putting a lot of unnecessary strain on the motor. With it on top of the frame, it's a shorter and smoother pull - so you can print faster and reduces motor skipping.
This will also help immensely if you use flexible filament.

With the 2020 extrusion it's really easy to bolt stuff to the frame :-)

[Columbo]

Good suggestion! Thanks aardvark.