Drying Times and Temps in Dehydrator  

RE: Drying Times and Temps in Dehydrator

Sorry, I had a bad day yesterday, right at the end of my shift, we had a power cut and once everything was back on, our warehouse storage system was kinda fried, is the best way to describe it, stopped over another 5 hours until 03:00 am to get the system up to a state that they can pick orders, albeit not at full capacity, swapping modules out on conveyors etc until one of our mobile guys made it in to take over, probably not going to have time for much else as when I'm back in, I still will have modules to swap out and software to mod etc etc.

Like I said before, work gets in the way of my hobby so no further with octoprint etc 😀

Guy, I take it you print full time as you have more knowledge about this subject than most of us put together.

RE: Drying Times and Temps in Dehydrator

I too use a Dehydrator but have also modified it so I can print from it.  Mine will hold 5 x spools which is perfect for the MMU2s.  Cheap, easy and works great.  I removed the plastic trays and cut a tile for the floor to make it more stable.

I also splashed out for an industrial Dry Cabinet (goes down to 0% RH) for storage of about 3 dozen spools.

RE: Drying Times and Temps in Dehydrator

As an example, here is a print using eSun ePA-CF (Nylon-Carbon Fiber) that prints beautifully when properly dry.  I love this filament for functional parts like extruder parts.   High thermal properties, great dimensional accuracy, and oddly light.  Beats PC for me. 

Edit - there was no clean up, this is how it came of the print bed!

RE: Drying Times and Temps in Dehydrator

Great stuff.  I have several spools to dehydrate.  

RE: Drying Times and Temps in Dehydrator

Left those two PETG spools exposed to room air (40% RH about 22C lately) and measured their mass daily. Both increased by about 1 gm/day over the course of 3 days.

Bunny Science lab got a better scale (o.01 gm precision / calibration capable) and is running a test with 5 PETG spools. They were all dried for 20 hours before double bagging. (ziplock freezer, 1 gallon bags) with 20 gm silica each.

Will remove spools from bags and measure mass change over the next couple weeks. Not much reason to check single bagging because we already know that isn't much good past two weeks.

Now that we have a better scale, it may be practical to record each spool's mass post drying and use change of mass to gauge adequate dryness before use. Probably more objective than just checking silica indicator color, but we'll see 

RE: Drying Times and Temps in Dehydrator

People here are mentioning storing filament in freezer bags, since I am interested in slow cookers and souse-vide, would vacuum sealer work for storage? Those usually create vacuum and melt the wrap to create a seal. Obviously it would need to be ripped apart every time one wants to use filament, then re-seal, which can get more expensive.

RE: Drying Times and Temps in Dehydrator

I'm thinking of changing my dehydrator since it is a big horrible round thing and I have to keep it in a box when not in use, its one of them oypla things and was the cheapest dehydrator I could get my hands on at the time.

I'm thinking of this now: https://www.klarstein.co.uk/Kitchen-appliances/Food-dehydrators/Arizona-Jerky-Dehydrator-500W-35-70-C-Digital-Touch-Display-Black.html?force_sid=fdsba6n76mfki2tn9qth9e36n6

Any thoughts?, that price crossed through of £229.99, I really don't know where they get these figures from as  this dryer is the same £99.99 price from various places, I'm sure they just pick a number, double it and add 15% and try and persuade you that this is how much it is really worth.

I like the fact this has an attached door with glass, not some flimsy plastic clip on front. Temperature adjusts in 5 Deg increments from 35 to 70 Deg (95F to 158F), and drying timer from 30mins to 19Hrs 30Min. Oh, I'm in the UK.

RE: Drying Times and Temps in Dehydrator

5 degree F increments is nice. It does seem a small unit, quite a bit shorter than the 9 shelf sized one.  Probably can do five spools max.

Very early data on double bagged PETG. Looks to be gaining about 0.5 gram/week. This is, of course, weighing just the spools taken out from the bags. We'll have better data in about a month. 

I'm really liking the higher precision scale for measuring moisture gain. I think I'm going to start tagging freshly dried spools with their mass. If they gain more than 2 gm, it's time to re-dry before use.

RE: Drying Times and Temps in Dehydrator

That's 5 Deg C. and I don't really need to dry 9 reels at a time, 2 to 3, up to 5 max, and it takes up less space. Shame it doesn't go up to 90 Deg C, as this would be good for Polycarbonate. I wonder if it is hackable 🙂

I'm quite surprised at double bagged PETG can absorb moisture, wouldn't have thought there would be enough in the air in the bags, let alone draw it in somehow.

RE: Drying Times and Temps in Dehydrator

You can dry Polycarb at 70C. I do that routinely, but it takes time.

10 hours for touching up a mostly dried spool. 20 hours for one that has not been processed.

I think the bags allow some degree of diffusion through the plastic. It is remarkable how much drier spools are that arrive in aluminized bags. Those probably diffuse less vapor through the bag.

RE: Drying Times and Temps in Dehydrator

Finally, found some reviews on the dehydrator in Germany (Clue was in the name Klarstein), and as a dehydrator it gets 5 stars from everyone except one person who downgraded it to a 3 because it had a plasticy smell when new.

So have gone and ordered it.

RE: Drying Times and Temps in Dehydrator

Looking around at dryers and such it came to me that I am going to be spending 20 spools of filament money on a dryer to save one or two spools ... why do we do these things to ourselves?

RE: Drying Times and Temps in Dehydrator

Posted by: @tim-m30

Looking around at dryers and such it came to me that I am going to be spending 20 spools of filament money on a dryer to save one or two spools ... why do we do these things to ourselves?

You're looking at a pretty high class of dryer! Most of the dehydrator solutions are at the $100 mark or lower, so closer to 4-5 budget spools, or 3-4 nicer spools. The filament isn't the only cost. It's the time and effort of getting partway through a large print only to have it go bad that makes the bit of extra work worthwhile, not to mention general poor finish and strength concerns that come from variable filament. I've been able to recover a half-dozen expensive spools using the PrintDry I was gifted last year for Christmas, so it's paid for itself in my book and should be good for a good bit longer.

RE: Drying Times and Temps in Dehydrator

$300 was the food dryer in question.  20 spools of  https://www.amazon.com/dp/B07VB7HFHW : but now it's even a buck less - so make that 21 spools.

RE: Drying Times and Temps in Dehydrator

I bought a food dehydrator for $78.  It will hold 2-5 spools.  Well worth the price.  

RE: Drying Times and Temps in Dehydrator

I'm finding even PLA - particularly the cheap stuff - benefits from a bit of pre-print "toasting". Any sort of PETG, nGen or other filament really benefits. My fine stringing problems are significantly reduces. If I'm going to spend hours working on a print, I'm ok with spending some prep time giving it the best odds of successful completion!

I'm sure it varies by location and environment. In Phoenix I doubt I'd need to worry. 

RE: Drying Times and Temps in Dehydrator

Posted by: @bobstro

I'm finding even PLA - particularly the cheap stuff - benefits from a bit of pre-print "toasting". Any sort of PETG, nGen or other filament really benefits. My fine stringing problems are significantly reduces. If I'm going to spend hours working on a print, I'm ok with spending some prep time giving it the best odds of successful completion!

I'm sure it varies by location and environment. In Phoenix I doubt I'd need to worry. 

I have to concur.  I purchased a dehydrator and a print dry.  I use the print dry while printing some filaments.  

RE: Drying Times and Temps in Dehydrator

For you color normals: what do these cards read?

RE: Drying Times and Temps in Dehydrator

I just jumped into the dehydrate cart. But found in my foirst test of the dehydrator that 60c is bad for some of my filament... lol.  Placed one of my newest vises into the thing to hold my temp probe and parts of the dang thing MELTED !!!  Well, changed size anyway.  The black PLA2 was unfazed, but the orange cheapo PLAx shrunk about 2 mm over a 70 mm length.  At 50c the new dehydrator is +/-5% ...ugh. And has a mechanical relay for power, and the click gets annoying after a bit.  So it'll be out in the garage where it can at least help take the chill off this winter.

I also have been playing with vacuum, food bagger levels for bulk air removal, plus a MightyVac to pull down a bit more.  It really seems a short stint 20-23 mm of mercury goes a long way to drying filament. Stuff I've been playing with - known fizzling PLA - goes in flexible and is coming out almost brittle, and is printing with no fizzle or stringing. Not that it was very stringy to begin with, but preheat ooze was gone, and no purge line to part string.  

RE: Drying Times and Temps in Dehydrator

Posted by: @tim-m30

For you color normals: what do these cards read?

They all are indistinguishable IME. Giving up on those.