BoxTurtle Dryer for the BoxTurtle enclosure

[fair plaza]

A higher power replacement for a PolyDryer. Currently a work in progress. So far it
works well. 1 unit can maintain 10% to 16% humidity for a standard 4 lane BoxTurtle enclosure.

BOM:
2 Wago 221-413 Lever-Nuts 3 Conductor Compact Connectors. https://www.amazon.com/dp/B06XGYXVXR
1 PTC Fan Heater 110V 100W. https://www.amazon.com/dp/B0DQCLKHRX
1 IEC320/C14 15A 250V Rocker Switch Power Socket 5A Fuse with 16-14 AWG Wiring. https://www.amazon.com/dp/B06XGYXVXR
10 M3 brass inserts.
Misc screws.
STC-1000 (Temp Controller) or STC-3028 (Temp and Humidity Controller)
https://www.amazon.com/Dorhea-Temperature-Controller-Centigrade-Thermostat/dp/B07R44SGLX/
https://www.amazon.com/dp/B08H7J2Z5H

With STC-1000 you can set a temperature range and it will maintain it. Turning the heater on and off as needed.
With STC-3028 you can control the heater by temperature, or humidity range. It can also be wired to use a combination of the 2.

I do suggest for safety that the 5A fuse be replaced by a 1A fuse which is just sufficient for this heater and controller.

Cost should be about $50 USD plus about 340g of ABS or better filament.

Next thing I'm testing is a 400W heater on a 8 lane enclosed BoxTurtle.

Wiring is very simple. See the photos.

Have a couple of changes to make then I'll be posting STLs.

Here's a comparison to the Polydryer and shows the 4 parts to print. The 4th bottom part is only required if you are using the STC-3028.

[cedar acorn]

Yeah I was very unhappy with the poly dryer performance. I guess I was expecting it to be a lot more like a regular dryer. I'm also trying to come up with some type of way to either share the environment with my printer or heat up the space of my enclosure for my box turtle. I want my filament to be warm/soft before it goes into my printer. When I took the poly dryer apart to flip the screen, I was really surprised that the contents it just being a PTC heater and a fan.

[hallow thistle]

I found the equivalent heater for 230 V from PTCYIDU but its height is 52 mm instead of 42 mm of the 110 V version. Is it still compatible with your case?

[fair plaza]

It should fit. I planned for both 42mm and 52mm heaters. The 400W unit I plan to test is 52mm.

[storm bough]

It’s great! It seems more efficient than the polydryer.

[storm bough]

I only can get the 110v 400w PTC fan. So the fuse might use 4A. Is there any print file release date?

[soft ocean]

I've got a DHT22 in my BTE with 3 poly dryers graphed in home assistant. Is this performance really that bad? I'd be curious the compare power usage 3 x 1 of these.

[fair plaza]

Working some final fit issues. Made the M3 holes too tight.

[fair plaza]

Here are the STLs. I printed it in ABS at 0.24. Wall loops 3. Top and bottom layers 3. 5% infill. All parts except body are printed top down with no supports. The body is printed bottom down with painted support on the bottom.

[soft ocean]

I'll make one. I have power monitoring now, for all three at once.

[fair plaza]

I added some power monitoring. Looks good from a consumption point of view.

[soft ocean]

The polydryers seem to pulse from 1w to 50-60w up and down all the time.

The blue line is all three together

[storm bough]

I think the dryer body not only one area need to use the support. So it need to auto generate support on this model. Also the 5% in fill might have some issue on the hot air tunnel’s bevel. I will upload some pictures later.

[fair plaza]

You may be right for 400W heater. I printed it with those options, but I do have my bridging setup pretty well. It's been running for 6 day straight with zero melting/distortion, but again at 100W not 400W. Please be careful with 400W and make sure to change your fuse to 4A.

[storm bough]

I will turn on only before printing, because I have some concerns about the 400w PTC heater. I don’t want to burn out my house.🙀

[fair plaza]

Looks like a cooling issue with your printer. Turn the print 90 degrees so cooling fans hit it at a different direction?

[storm bough]

It still can use. Just looks not good.

[fair plaza]

Note there is fitment issue with the 400W heater. I'm printing a test to resolve the issue. It's clearance of the power wires and the top tab of the heater. Currently the column between the two is 7mm wide. it needs to be 4.7mm or smaller. I'll post an updated STL after I test.

[fair plaza]

While changes were made to fit the 400W heater the chamber design and recommended material need to change. The 400W heater pushes out air at 144C which melts ABS overtime. Something like PA12 will be required.

[frank ermine]

github on this yet?

[fair plaza]

Not until I get a releasable version.

Started a redesign of the hot side of the dryer. Changing it into an insert that can be printed separately in high temp resistant material. This way the body can be printed in ABS and the hot side can be printed in something like PA12.

[fair plaza]

Note the STLs are attached to this dicussion. They are usable with a 100W heater. They are not usable with a 400W heater.

[frank ermine]

i can do ABS... PA12... pcpway for me lol

[fair plaza]

Unless you have more than 4 lanes in your BoxTurtle a single 100W heater will work great. Which can be all ABS with no problems. Part of my goal is drying out my enclosed 8 lane BoxTurtle.

[frank ermine]

i don't even have a box turtle yet i just really like the design

actually currently learning about MMU's by working on the 3MS

[cold finch]

So how'd you run the 3028 sensor.... wallow out the sensor tube and pass the connector through or something more creative?

[fair plaza]

Take pins out of the connector with an Xacto knife. Take a picture before removing the pins from the connector so you know what order they need to be in. Feed line through then reinsert the pins into the connector.

Everyone. Please do not use a heater greater than 100W with this design. It is more than enough for a 4 lane BoxTurtle. Any heater greater than 100W will melt printed ABS. Be safe!

[cold finch]

One other thing- your 3028 link is to a 12v powered version device so an additional 12v power supply appears to be required. 120v versions are there also.

[fair plaza]

Yep. Link was originally for 120V version.

[fair plaza]

Here are the updated STLs.

[lilac oxide]

So best is tu buy some sls pa12 printed parts for the heater I suggest?

[fair plaza]

I printed all the parts in Polymaker PA6-CF. Handled the 400W heater with no problems.

[languid estuary]

Putting one of these together this weekend, looking forward to box humidity lower than 45%..

[fair plaza]

Good luck. Let me know if you have issues. What watt heater are you using?

[languid estuary]

just the 100. garage humidity gets real high in the winter but I'm hoping it's enough

[languid estuary]

just got it put together and tested, now for the bake-in. lookin good so far!

[fair plaza]

What type of filament did you print it in? I would expect lower humidity. What is the ambient humidity outside the boxturtle?

[languid estuary]

that was while it was still coming down, I had to adjust the controls and stuff still too. much better now

[toxic swift]

What wattage heater would you guys recommend to get the "chamber" up to 80c for drying? I've got high temp materials that I'll use to print the parts.
Currently my double polydryer only get up to about 45c

[toxic swift]

I've ordered a 250w heater. Will report back

[dense veldt]

ordered a 300w heater that should come just before xmas. It was cheaper than a 100w! Going to print the parts over the next few days

[tribal wraith]

What material are people printing this in?

[zealous sandal]

#1398445432023285800 message

[fair plaza]

ABS for 100W. For 200W Internal hot side and vents should be PA-CF (Nylon Carbon Fiber). For 400W all parts should be PA-CF. Also for 400W make sure power socket is using 14AWG wires,

[fair plaza]

What did you end up printing your parts in?

[dense veldt]

ASA and PA

[fair plaza]

Can you send the link for the 300W heater you found?

[dense veldt]

it was one on Amazon. However I'm going to downrate to a 100w one as it was melting any PLA I put in the boxturtle

https://www.amazon.co.uk/dp/B0FX3TMG91

[fair plaza]

Which controller did you use? You should be able to set target temp and/or humidity to work with PLA and ABS/ASA. PA requirements can cause issues with PLA.

[dense veldt]

An ST-3028. Where have you been placing the temperature sensor?

[fair plaza]

The intake vent mount. See the file "STC-3028_Sensor_bracket-NoFins.stl". You will have to remove the pins from the connector to feed the wire through the provided hole/tube in the body. Inside the intake vent.

[dense veldt]

That's where I'm going wrong then

[lilac oxide]

I have a question about the heater power : would it be enough to use a 100 to 150 watt heater if you print mostly with abs and asa?

I'm thinking of building 2 HTLF and a isolated (mdf and acrylic or glasses door) 8 roll filament chamber that can be also used as a dryer for pla and abs.

[toxic swift]

What filament would you print it out of? From what I have read you would need a 100w heater if the parts are in ABS. I got the 250w heater and while it works great, it's putting out air at about 150c so it's not on for very long. That's only on a 4 roll enclosure.
It would be interesting to see what temps the 100w and 150w heater can get the enclosure up to. If I had to choose between 150w over the 100w just to have the ability to get the enclosure up to 70c to dry ABS/ASA as quick as possible.

[lilac oxide]

Ah OK mostly pla for decorative purpose and one with petg abs and asa

So I guess 100 to 200 would be fine for a 4 roll

For the last 3 50 to 70 degree is fine

As far as I know you need 100 to 120 degree on the heater to produce 60 to 70 air heat.

[glass peak]

hello, how did you the best flow redirection ? I am doing similare heater with 4020 and 200w heater in 24v, i want just more secure and add mosfet/ thermal switch/thermal controler (another version) and timer. For blowing shield i do something like polydryer

[fair plaza]

Read up on the specs of the STC-3028 controller. Has both temp and humidity control for the heater. No timer in it.

Everyone. In general for filaments. Minimum filament is ABS/ASA for all parts. For 100W heater ABS/ASA for the "HotSide" body will work. For a 200W heater the "HotSide" needs to be PA-CF (Nylon with Carbon Fiber) or better rest can be ABS/ASA. For a 400W heater everything needs to be PA-CF or better. I used Polymaker Fiberon PA6-CF20.

[glass peak]

I use bme280 on esp32 is the same thing. But i prefer use timer. With 200w heater it can be use for anneal

[toxic swift]

Just some warning, that I expected might happen. It was my own gamble, but my 250w heater fully fused the ABS parts to the heater and vents. Even my polycarbonate parts got slightly melted. I'm reprinting the parts and I'm going to swap to a 100w heater and see how that goes.
I think because I kept the chamber temperature around 70°, the intake air is hotter so the air that comes out is too hot.

I was able to get the old heater out by putting the whole thing in a filament drying oven to soften the ABS 😂

[fair plaza]

Ouch. This unit is not intended to keep a constant temp over 60C. Note PA-CF (Nylon Carbon Fiber) is recommended. Also the included none fined intake and output mounts are also recommended. Fins get too hot and deform. Also you want to use the mount with sensor mount for STC-3028 as the input (front) mount.

[fair plaza]

How many wall loops are you using? I would recommend 3 or 4. Also 3 or 4 top and bottom. Higher wattage heaters should use 4 for walls, top and bottom.

[toxic swift]

Yeah you're right! I really wanted a finned output to spread the hot air.
I printed one out of PPS so it should hold up with a 100w heater.
Here is a pic of my old setup with the nicely mounted sensor.
I used 3 walls with 23% infill, the new one is with voron settings 4/5/5.

[fair plaza]

Let me know how PPS works.

[toxic swift]

Really well but I'm only running the 100w heater. The vent still looks new after many hours of full temp.

[fair plaza]

What thermal camera are you using?

[toxic swift]

I don't see it for sale anymore but it's called "tooltop t256 thermal camera"

I think they must have a newer model out

[severe beacon]

Best orientation for printing hotside mount?

[fair plaza]

Yes

[fair plaza]

What watt heater are you going to use? Note PA-CF is recommended for the hot side.

[severe beacon]

I am planning to use PA-CF, running through my checks before i print this part... its a lot of filament to get this print wrong

[misty olive]

ABS still okay for hot side if using 100w heater?

[fair plaza]

Yes

[misty olive]

Excuse my ignorance, but I was not able to find the exact rocker switch as you used but found something similar with only 3 pins.
Do I need to ground this thing to anything?

[fair plaza]

Here's an option. https://www.amazon.com/dp/B09X1VZ852

I really suggest using a IEC320/C14 fused module. With 16-14 AWG Wiring.

[misty olive]

https://a.co/d/09Phs99B

This is the one I ordered. It has 16 gauge wire. Just not sure what to do with the ground wire.

[toxic swift]

The ground wire doesn't connect to anything after the switch. The heater only has two wires and the STC unit doesn't have a ground connection.

On OP's post you can see the ground pin is not used
https://media.discordapp.net/attachments/1398445432023285800/1398445434271432775/PXL_20250722_212405903.jpg?ex=69b5450d&is=69b3f38d&hm=dc9e67e48a4be587aa6885bf36259941da7160d899b8b1e492ee93335b638504&=&format=webp&width=1848&height=1392
Im running it without as well

[fair plaza]

No connection for the ground wire.

[misty olive]

Love it!

[fair plaza]

What size heater (Watts) did you install? Also what filament(s)?

[misty olive]

100 watt. Ambrosia ABS-GF.

[lilac oxide]

What temp can you reach with that heater all over?

[toxic swift]

On max, my 100w heater hovers around 65c, with around 24c ambient. It's got insulation on the top, back and sides.

[misty olive]

I used 100w heater and have the ST-2038 set to turn on at 17.5% humidity and turn off at 14%. At its max it gets up to the mid 50’s while drying.

I don’t have any insulation. Just standard BTE build with the rubber seals for the panels.

I’m sure I could optimize it more but it is doing what I want it to do and has very set and forget thus far.

[half pulsar]

what's the recommended print orientation for the main box? Just with the little feet pointed down and supports?

[toxic swift]

Yeah with supports. I split my model near the base so I don't need supports. I just acetone welded the pieces together.

[half pulsar]

Hmm, what are the odds of the fan dying, and then the heater running away and melting its housing? Or am I just being paranoid. I do see they spaced the fan away from the heater on the polydryer.

[fair plaza]

The controller should prevent run away. There is also a fuse in the plug assembly if it starts pulling to many amps.

[half pulsar]

My paranioia is a procedure something like this:

1. thermistor is inside enclosure
2. fan dies
3. heated air is no longer blown into enclosure
4. controller sees no temperature change, leaves heater on
5. Heater is still fed a fixed 100W. Temperature still only rises while this is happening. Fuse doesn’t trip since the (momentary) power draw is normal.
6. chamber temperature doesn’t really move because the hot air is still stuck in the dehydrator unit, so the controller keeps heating
7. heater melts everything around it and sinks down

if the controller has a “heater response too slow” equivalent like klipper then the 4-6 loop would get broken of course

[half pulsar]

So one of my turtles is under a shelf and has height restrictions, so I made a version that moves the controller to the side. the 3028 is quite small so this isn't actually that much shorter, but I figured that out... way too late

I haven't done a full-size test yet, but the chopped up parts all fit fine. Figured I should post it since it would be another week or two if I get sidetracked on something else.
Edit: one of the internal indents is wrong, don’t print the main box 🙃
(some more minor problems, will post again when I've actually printed and verified them)

[fair plaza]

Nice mod.

[half pulsar]

Ok, looking good. Plugged it in and got hot air from the correct vent. I might be able to compress it back down to a single vent-pair later.

[half pulsar]

Also, looking at the polydryer design, it has holes in the outer shell to "expel moisture", but the inner shell doesn't actually have any corresponding holes in the airflow vent to let moisture out?

[fair plaza]

As I understand it. The holes help prevent moisture in the camber containing the electronics.

[half pulsar]

Noted, I will punch some stylish vents on my next pass then

[half pulsar]

I had these done a few weeks ago, but been procrastinating on actually installing them. The lid bulges a little if you use fat twist caps like me, but that shouldn't be an issue if you run wires long enough or use small twist caps / wagos.