Nylon printing problems

[AndersK 59]

Hi all

I'm having difficulties printing a nylon part using Nexeo Novamid ID 1070 (production part will be PP but I dont have such wire)

 

Main problem is to get it to stick to the bed. Have tried different print temp, bed temp, glue, without glue, different materials....

Rather thin compared to size which make me believe is the major concern, 160x50x1 mm

 

Tried both brim,  raft and without extra bed adhesion (brim size varying from 0 to 12mm)

Tried bed temp varying from 60 to 115°C, the brim warps even before the geometry starts printing. The bed seems to heat up as it should

 

Print temp from 230-280°C. Printing below 260° makes the circular details fall of, almost doesnt bond at all.

High temp seems to burn the small hinges

 

 

Printing in ABS gave good results but its too brittle for the hinges that has to be flexible 

 

Changed to Nexeo Novamid ID 1030 which gave better results when pushing the material at 200% for the first layer. Still some warping at one end and much more difficult to remove  the brim 

 

 

 

Any suggestions?

[MechDesigner 3]

I use 3dlac spray you can find it on amazon.  works real good.

Do you have the door and top cover for your printer?

 

https://www.amazon.com/3d-lac-3D-Lac/dp/B075D7T664/ref=sr_1_1?ie=UTF8&qid=1533820227&sr=8-1&keywords=3dlac

 

Frank

[AndersK 59]

Looks like its solvent based, not allowed to bring it in here then...

 

Yes, have door and top cover, cooling fan disabled. Just running a fan with HEPA filter but that one just circulate inside enclosure

[MechDesigner 3]

Did you try painters tape?

put the tape down a little larger than the parts brim, re-level bed.  I used isopropyl alcoholl to whip the sheen off the tape.

also I added stick glue to the tape.

after the brim is done use more tape to tape the brim down.  This is what I did before the 3dlac,

also have you tried to print only one part,  so far I have had no luck printing multiple parts.

[AndersK 59]

Thanks, I'll give that a try tomorrow. 

It is one part I'm printing, even though it looks like 4.

I actually wanted to print 3 of these for a full bed. Need a bunch of them to test  the concept (custom masking in a paint process)

 

Just started a print were the hinges are moved to the flat face, wider and higher. Means building on a bed of support material. Will see the result tomorrow.

Edited August 9, 2018 by AndersK

[kmanstudios 1,120]

I have increased the stickability of my PVA slurry by adding basic Isopropyl Alcohol to it. This cuts surface tension and makes for a really clean, thin layer of slurry that I apply with a brush.

 

Also, looking at the prints, it seems you could buffer up your brims a bit. If you are printing a slue of them, then move them close enough to share the brims and that will increase brim adhesion. They also come off as one piece and it is easier when pulling the parts from a freezer.

[gr5 2,167]

So I've printed many brands of Nylon including novamid 1030 but not novamid 1070.

 

You want the bed temp as high as possible.  Nylon will be fine (won't melt) usually at least to 120C but 100C should be hot enough.  Nylon is actually easier for me than other materials because it is already somewhat flexible which is critical to avoid warping.  Nylon gets more and more flexible gradually as it gets warmer so at 100C it is quite flexible.

 

There are 3 good ways to properly create the proper pva surface on glass.  But first start over and clean the glass and get everything off of it.  Then you can use one of these 3 methods:

1) glue stick - you probably were doing it wrong - put down glue stick such that you leave bare spots on half the glass (just put down separated stripes) then use a wet tissue to spread it evenly and to remove 80% of the pva.  This will give you a good extremely thin layer of pva.

2) hair spray -  This is quite simple and hard to mess up but if you go this route remove the glass from the printer as you don't want glue in your printer particularly the Z screw.

3) slurry.  This is easiest in the long term.  Mix chunks of pva with water or mix elmers wood glue with water (1 part wood glue 10 to 30 parts water).  Shake it up well - if using solid chunks of pva let it dissove for several hours.  Use a paint brush to spread this mixture on the bed, heat the bed to 60C or hotter and by the time the temp reaches around 60C the water should evaporate leaving an almost invisible layer of wood glue.  kman (post above) adds alcohol to the slurry.

 

To understand why parts curl off the bed and all the other details (you need to squish the bottom layer into the glass hard) watch this video:

 

 

Oh!  One more thing - you can reduce warpage and improve layer bonding by covering the front and top of your UM3.  Just use a gallon ziplock for the front and a cardboard box for the top.  This will raise air temps to around 35C which will reduce shrinkage (until print is complete) and help with layer bonding and help the heated bed get up to temp faster and stay at 100C or 110C.

 

[gr5 2,167]

And use brim.  lots of brim.  You have to cut it off after but it's worth it.  You can probably get away with no brim for these small parts but not much larger parts.

[AndersK 59]

@gr5 , that's a great video. Well done.

I've been on to most of the tips there but I think I've used too much glue. 

Will clean and redo tomorrow.

 

And I do have a top cover and proper door to keep heat in.

[AndersK 59]

17 hours ago, gr5 said:

1) glue stick - you probably were doing it wrong

 

Yes, I did it wrong and I stand corrected in shame ?

 

Did another try this morning by cleaning the table and only applying tiny amounts of glue, compared to previously attempts, wiped with wet tissue. What a difference....

 

Thanks all for the other suggestions, I'll keep the other things in mind and will explore later.

 

[JohnInOttawa 104]

dumb question of the day - no longer have the original glue stick.  Which ones use PVA?

 

As an aside, I must be the only woodworker I know who no longer has any PVA glue in the shop.  Everything has additives that I probably don't want on my build plate. 

 

If there was an anti-matter version of perfection, I would achieve it....

 

Thanks

John

[gr5 2,167]

All of the glue sticks at the office supply stores and such - anywhere they sell paper and pencils - those are all PVA.  Don't worry about additives.  elmer's wood glue is great.  I'm sure the original elmer's glue would work as well also as it's mostly pva.  Those glues are mostly PVA.  Hairspray is mostly PVA - (this is a case where I don't like additives because I can't stand the smell after a while).  

 

If you use hairspray you need to remove the glass each time you spray which is extra work (you don't want pva getting on the z screw!).

 

One coating of any of these methods lasts at least 5 prints if not 50.  when parts start to stick too well then you know you need to add some more glue.

 

[kmanstudios 1,120]

1 hour ago, JohnInOttawa said:

dumb question of the day - no longer have the original glue stick.  Which ones use PVA?

 

As an aside, I must be the only woodworker I know who no longer has any PVA glue in the shop.  Everything has additives that I probably don't want on my build plate. 

 

If there was an anti-matter version of perfection, I would achieve it....

 

Thanks

John

You can also recycle your PVA from printing and make a slurry. I have, at this point, enough PVA to probably supply half of Manhattan with enough dry PVA to make slurry from. Since it is designed to work with the printers, and, I just hate waste like you would not believe, this is my go to solution. I have found that if I add alcohol to it, it makes a thinner, more even bond with the prints and printing surface.

 

I have printed a bar to make a mold from (Have 3 pounds of dry dental alganate waiting for this) and make PVA bars out of so I can give them to people when attending printer functions. It is just a bit of a pain to make as you have to put in the slurry, let it dry, which makes it lose volume, then, put more in. Takes a while for it to dry out as well. But, no worse than making homemade soap I guess.

 

1 hour ago, JohnInOttawa said:

If there was an anti-matter version of perfection, I would achieve it....

I will take that bet and raise you one...... I think it is just the universe testing us all..... ?

[JohnInOttawa 104]

Thanks gents!  I bought a glue stick and will try out the slurry.  Thought of doing it this morning, but thought it might take some time for the first run.  Of course, with the printer tied up for the rest of the day now, I guess I have time....

 

Much appreciated.

John

[JohnInOttawa 104]

Sooooo  Good news and 'learning'.

 

Glue stick (with good advice applied, thinned out with a damp tissue), worked perfectly. Flat, no warping, came off without taking any glass afterward.

 

'Learning:.  Ironing.  I had slowed down the print speed to ensure the quality was where I needed it.  Worked great.  But then I decided to tick 'ironing' at similary low speeds, on a piece with lots of corners.  From the already pretty good finish, Ironing produced three distinct textures.  At the start of the corners, surface quality was slightly better than non ironed.  Mid length lines were amazing, just about zero discernable lines.  But then we got to the corners on the end, and, well, it just created a melted blob, effectively destroying what needed to be a flat surface.

 

No biggie, this wasn't intended to be the final print anyway, just checking dimensions, but note to self.  Easy on the ironing with nylon.  (BTW this effect worked perfectly on the PLA version of this print).

 

Thanks again for the advice!

John

[AndersK 59]

I got similar results with ironing on nylon too so I switched it off.

There are probably some parameters to adjust but I'll leave that to later prints.

[JohnInOttawa 104]

First part is done, new day, new design, new question!

 

I'm printing a part now that has a circular 'dog', upward facing teeth around the perimeter.  Cura showed no issues, but, while the rest of the print turned out fine, the toothed ring turned into a nondescript raised roughened, mostly melted, area.

 

I'm pretty sure I am missing an essential technique for managing the small, rectangular pyramids that represent each tooth. 

I ran a 0.4 AA core, Ultimaker black nylon, 0.1 layer height, 250C and no fans.

 

Thanks in advance!

John

 

Edited September 4, 2018 by JohnInOttawa

[kmanstudios 1,120]

I would have to see the print to make a guess.

[JohnInOttawa 104]

Sorry I didn't add it earlier, was soaking out the PVA.  Post is updated with the print pic. 

 

Thanks again

John

[AndersK 59]

Looks like you're dragging material over the surface.

Check your retraction parameters so you get retraction between the small features (minimum travel)

With the nylon Im printing I had to increase retraction a lot.

 

Have you tried adaptive layers?

Can really help when you have a model with small or sharp features to reduce print time and still give a good resolution.

 

 

[JohnInOttawa 104]

Appreciate this!  I will isolate that part of the print and try it again on Thursday.  I had not considered adaptive layers and will adjust retraction, will post the results back here.

 

I had also slowed down my print speed, maybe too much.  I'd welcome advice on what others have found to be optimum.

 

John

[AndersK 59]

This is what I use, havent fiddled with this at all so it might not be optimum settings