This instructable will show you how to modify your Crock Pot to cook up some deliciously fresh Filament!
As we all know, over time, moisture can get inside of our filament. Slowey turning our favorite rolls into brittle garbage. We store them in safe places, take time to care for them like children. But, in the end, they often turn into the sad shell of the former glory they once provided. Sad but true, makers in tropical climates have but only one option, Print as much as you can, as fast as you can, before the roll has passed on to the shelf of worthless money. To valuable to be tossed aside, yet to brittle to be put to use.
One day, we heard a rumor. Filament can be put in the oven and baked bake to life. We felt overjoyed, so many colors sitting on the shelf waiting to be brought back to life...But it was mostly a waste of time. Some rolls seamed to be printing better, but not like before...before the moisture. We put our filament back on the shelf and accepted our fate...
-The Negative Atmosphere Crock-Pot Heating Method-
The problem with most attempts and devices used to dry filament is; they rely on heating the filament to a high temperature for a long time. As the moisture leaves the filament, the filament is often distorted in the process, losing all of its precious dimensional accuracy. So, even if it works in drying it out, the filament will often perform poorly because of its now, inconsistent shape.
To solve this, we need less heat and less atmosphere!. By pulling a vacuum on the inside of the Crock Pot, 100-150 degrees Fahrenheit becomes more than enough temperature to safely dry our filament!
By following this instructable, you will finally be able to bring those filaments back to life!
I may be offering a product in the near future based off what will be explained here. Consequently, the patents are pending. Feel free to contact me regarding licensing.
Step 1: What You Will Need
1 - 7QT Crock-Pot - I used a 7qt Classic brand name Crock-Pot. Its a great price and big enough to fit any of my filaments, it does the job perfectly
2 - Device that can pull a strong vacuum. I used a MityVac brand handheld vacuum.
3 - Hose that not only fits on your vacuum, but also the nipple on the bottom of the Crock-Pot
4 - Silicone Tape and some Silicone caulk (I bought mine at the hardware store)
5 - Petroleum Jelly or Silicone Release agent. This is used to coat the lid when making the seal
6 - Old Filament that just wont print right
Step 2: Remove the Removable Stoneware
Take the heavy stoneware bowl out, we wont be needing any of that here.
Step 3: Attach a Hose to Pot.
On the inside of most Crock Pots are one or more holes that are used to keep the bowl empty of liquid. Flip the pot over and you will see a little nipple. Attach the hose to the nipple you wish to connect to your vacuum, use a hose clamp.
Step 4: Seal the Remaining Holes
Now, use some silicone to seal the gaps around the holes and on the lid(where the screw is found). Take note of which hole you have connected to the hose. Fill the other hole with silicon to seal it shut. Remember leave the hole that is connected to the hose free of obstructions. On the outside, I use a hose clamp and a piece of silicone tape to seal the second hole even more.
Step 5: Apply Silicone to the Inside Top of the Pot
This will be our custom air tight gasket. Apply Silicone to the inside of the Crock-Pot.
Step 6: Put Petroleum Jelly on the Lid
Put a bunch of the jelly around the edge of the lid. This will act as a release agent so that the lid can easily be removed from the dry silicone.
Step 7: Carefully Place the Lid Onto the Pot
The Silicone will dry and make a perfectly fitting seal for this lid. You can lightly blow into the air hose to make sure it seals correctly. Don't blow to hard, just enough to see the lid rise a little bit.
Step 8: After 24 Hours, Its Ready to Use!!!!
After it is dry and holds a vacuum, you are good to go!
Step 1 : Place a bad roll of filament into the Crock-Pot
Step 2 : Set the Crock-Pot to "Warm", let it warm up for 10-15 min
Step 3 : Connect your Vacuum line to a vacuum and pull a few kpa (-5 to -10)
Step 4 : If it is NOT leaking, we should put a piece of floss in between the lid and the seal. The movement of air is necessary for evaporation at less than boiling temperatures.
Step 5 :Increase the vacuum incrementally. be careful and wear eye protection. at -40 Kpa, you could have 400lbs pulling on the lid. You need enough vacuum to help the water evaporate from the filament, but you don't need to make it a total vacuum! You will get a feel for it as you use it. Safest way is to start out with a higher tempature and less vacuum. Something like -20 Kpa and 180F and see how it goes.
Step 6 : Enjoy your filament's second life!
Next time I dry some filament I will run tests to get quality data.