PLA settings for diamondage ?

Hi Guys, got some black 1.75mm PLA from Diamondage [diamondage.co.nz] after advice to buy from them

Great company to deal with, very fast and friendly (and heaps of samples sent)

However, i cant get it to extrude as nice as the WHITE PLA that came with my Huxley from RepRappro , when extruding it has bubbles in it, and i get lots of very fine "whiskers" as the head transitions from one place to another.

I dont have a micrometer, but visulally is also looks to be slightly thinner

any thoughts ? temperature related ?

I suggest getting some digital callipers. Dick Smith has them for about $15. They take away a lot of the guesswork, as they are accurate to about 0.01mm . They are also handy for custom designing parts for things.

The bubling coud be the temperature, maybe adjust it a little lower. It could also be moisture in the PLA. Vik has suggested putting in a very cold (50C) oven for an hour or so, I haven't been game to try this. Try putting the spool in a plastic bag with some silica gel.

thanks, will try the silica gell

played around with temperature, 175 to 185 deg C extrudes quite nice, horizontal holes (3mm diameter) "droop" quite badly, where the original PLA dosent, but certainly the lower temp is working better.

Are you using fan cooling. I find PLA just will not print well with no cooling

im not using cooling.....but the PLA that came with it (from reprappro) printed without the issues, and at a higher temperature

i seem to be getting much better results at 180 deg C, still a small amount of spider webs, and the horisontal holes sag consdereably

Measure the filament, run a fan and watch out for printing on rainy days. I have tried a range of colours from Diamondage and they are all very good to print with and totally consistent diameter for the whole drum. However I have had the issues you talk of with both white and brown but not all the prints, just the odd one or two so probably something other than the filament like the humidity etc. I haven't worked through the whole spectrum yet but the best colours I have found for printing are yellow, sky blue, orange, black and red. I used a spool of transparent Ruby and much as I like the finished article, I find it harder to get it to flow right than the basic filaments.

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Richmond, New Zealand
Thingiverse ~ YouTube

I'm pegging it on moisture content. I just finished building my first reprap so I don't have a lot of experience but I know from the plastic injection moulding industry that it's essential to dry any plastic before moulding.
Diamondage packaging is a thin polythene bag and I had taken my filament out of the bag and left it on the concrete floor in my basement workshop so it had plenty of time to absorb moisture from the air.
Most of the other suppliers that I have seen ship the filament vacuum packed and heat sealed in a sturdy bag with a dessicant silica gel sachet inside.
I was having very poor results with sputtering and oozing messing up the prints. Being a new printer and my first attempt I didn't know where the problem was but a thread on another forum described the symptoms I was seeing as being related to moisture content in the plastic. I tried drying some in the oven. I set the oven to 60° and that was too hot, over 70° on my meter. The filament went soft as spaghetti and started to stick to itself. If you are trying it out for the first time test it on a couple of metres first not a whole roll!.
Then I saw my wife's dehydrator and thought that looked perfect. I had to set it on the lowest temperature which was supposed to be 35°C but actually produced 55°C according to a thermocouple probe I have. I left that in there for about 6 hours. The next run, with the same settings as before, I got a smooth continuous stream from the extruder.
I was using 200°C for the extruder but it also worked down at 185°.
I do think it needs to be done over several hours rather than 1 hour. Mainly because you are so limited by the safe temperature you can heat it to.
I'm going to do some more experimenting to confirm the theory but I read your post and thought I should share this with you now.
I would be grateful if others could feedback whether they've tried to dry material before use?

thanks Mike

what i have found so far, extruder at 185, it still looks a bit bubbly, and i get a small amount of micro "strings" between movements , from what i have read, could be entrained water, turning to steam, but i dont think so, it seems to just be this black PLA, as the Orange that arrived last week, at the same setitngs looks competely diferent, no strings

now have some IMPLA (20 impact modified) and its a diferent game again !, needs cooling early on to stop warping/distortion

I tried some samples of the IMPLA and the high impact PLA. They certainly warped more than the plain stuff.
Vk's clear PLA worked well for me. It should, since it has no additives at all.

I'm printing with Diamondage's Black PLA (3mm) with 200°C for the first layer and 185°C for the rest.

I'm pretty sure that moisture content is a significant issue. I'm keeping all my filament in a dry box now. With a load of silica gel sachets.
The relative humidity in the box is about 20% compared with ambient which is about 60%.
20% relative humidity is a dew point of around 0°C. The processing guidelines for the PLA resin say to dry to a dew point of -35°C before extruding it.

I've found that the plastic absorbs moisture from the air fairly slowly. It starts to get noticeable after the filament has been out of the dry box for 24 hours.

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[www.makershop.co.nz]
Makershop - Reprap parts, adding new stock almost daily.
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Hi,

I have been doing some printing with pla from diamondage also, all standard 1.75mm PLA

Findings so far,

Purple. 185
Black 180
Amber Orange 180
Orange 185
White 170 any hotter and it start spitting chunks out 170 its perfect
Translucent blue 180

This is where I am at to so far, these were all printed to a heatd bed at a start temp of 70 for the first layer dropping to 50 from there.

Cheer's Stubbienz