this post was submitted on 24 Sep 2026
298 points (96.9% liked)

3DPrinting

23815 readers
678 users here now

3DPrinting is a place where makers of all skill levels and walks of life can learn about and discuss 3D printing and development of 3D printed parts and devices.

The r/functionalprint community is now located at: or !functionalprint@fedia.io

There are CAD communities available at: !cad@lemmy.world or !freecad@lemmy.ml

Rules

If you need an easy way to host pictures, https://catbox.moe/ may be an option. Be ethical about what you post and donate if you are able or use this a lot. It is just an individual hosting content, not a company. The image embedding syntax for Lemmy is ![](URL)

Moderation policy: Light, mostly invisible

founded 3 years ago
MODERATORS
j4k3@lemmy.world
andypiper@lemmy.world
GrayBackgroundMusic@lemmy.zip
298
Tired of expensive disposable batteries and rechargeable AA suck. So I made a 10k mAh pack for my deadbolt. (sh.itjust.works)
submitted 22 hours ago* (last edited 22 hours ago) by ThePantser@sh.itjust.works to c/3dprinting@lemmy.world
173 comments fedilink hide all child comments
 

Eneloops would only last about 3 weeks. And disposable last 2 months. This door is used a lot and since it has Zwave and a door open sensor it sends info on every open.

Bonus, since it can handle the lipo AA batteries that put out 1.8v and it gives the motor more oomph I made the battery pack give 7.2v and it never sticks anymore.

This is a garage-door so its not critical access but is used a lot.

top 50 comments
sorted by: hot top controversial new old
[–] modus@lemmy.world 4 points 4 hours ago

What about mounting a wireless charging pad to the doorframe to keep it charged? Is that an option?

[–] BlackLaZoR@lemmy.world 9 points 7 hours ago (1 children)

rechargeable AA suck.

No they don't

[–] Zedd_Prophecy@lemmy.world 3 points 5 hours ago (1 children)

They do ... 1.2v output is low compared to the 1.5v alkaline .. they lose charge as they sit there doing nothing unless Enerloop which is expensive and still 1.2v - I recently converted the wife's led candles (2 x AA) each to 2 18650 each and now I don't have to charge the things for 15 or so weeks. This guy knows.

[–] AnyOldName3@lemmy.world 1 points 4 hours ago (1 children)

The internal resistance is much lower than that of an alkaline, so for some applications, a 1.2V NiMH will match or beat a 1.5V alkaline, but if you really need the extra 0.3V, then they're really pants.

[–] InFerNo@lemmy.ml 2 points 2 hours ago* (last edited 2 hours ago)

I bought rechargeable AA lithium batteries. They have a usbc slot on the positive end. Really handy. They do 1.5V.

[–] NarrativeBear@lemmy.world 3 points 5 hours ago* (last edited 5 hours ago)

This is great, so far I have only seen hardwired options, never seen someone do a expanded battery mod for their smart lock.

Battery eliminators are the way I hardwired my smart locks. You can find these on amazon in various battery sizes and combinations. Combining this with a Voltmeter Adjustable Boost Modul, doing some wiring, and then plugging all this into the wall means no battery changes every 3-4 months.

Here's a video of something similar to my setup.

https://www.youtube.com/watch?v=A4GRCACR0sM

[–] the_riviera_kid@lemmy.world 32 points 10 hours ago (3 children)

Wait until you hear about this neat invention called a "key". They are quite wonderful, they can securely lock and unlock your door in any conditions and don't need those pesky batteries.

[–] MagicDonkey@lemmy.dbzer0.com 6 points 7 hours ago

Wait until you hear about this neat invention called a "smart lock". It uses this marvelous key invention you kindly detailed but it also uses magic powered rocks that can send small vibrations in the air to communicate with other magic rocks at home. If their magic energy source is depleted the object you refer to as a "key" may also be operated on this mystical lock to which the lock then whispers: "just let people enjoy things".

[–] Joelk111@lemmy.world 4 points 7 hours ago (5 children)

Damn, didn't know they made keys that automatically lock the doors when I leave the house so I can't forgetfully leave the doors unlocked.

[–] Evotech@lemmy.world 2 points 2 hours ago (1 children)

Wait till you hear about memory

[–] Joelk111@lemmy.world 2 points 2 hours ago

Pretty sure I can't afford that these days

[–] clay_pidgin@sh.itjust.works 8 points 7 hours ago (1 children)

There are bolts with a clutch, so they are always locked from the outside and unlocked from the inside. Pretty handy.

[–] Joelk111@lemmy.world 3 points 6 hours ago* (last edited 6 hours ago) (2 children)

I'm not sure I understand how that'd work. How would they know when the door was closed so they could automatically lock the deadbolt? Or would you need to use a key to close the door from the outside?

[–] clay_pidgin@sh.itjust.works 2 points 4 hours ago

The one I've seen was mechanical, not electric. The interior handle can open the door irrespective of the door being locked or not.

[–] ContriteErudite@lemmy.world 2 points 5 hours ago (1 children)

They are expensive, but they do exist, it's called a mechanical keyless deadbolt. A local makerspace put one on their back entrance so that members/employees can come and go after hours without having to give everyone a key or use a smart app.

[–] Joelk111@lemmy.world 3 points 5 hours ago

Ohhh, there is a keypad but it's mechanical. Neat!

load more comments (3 replies)
[–] mrgoosmoos@lemmy.ca 8 points 10 hours ago (12 children)

the batteries in mine last a year and I don't have to carry around any keys but my car keys (when I take the car).

definitely worth it. I can leave the house with nothing but my phone or bank card and run errands etc. people can access my house when I want them to without issue. it's a huge QoL improvement for me

that said, I'd still prefer an electronic lock that had a key as well, and wasn't a touchscreen

load more comments (12 replies)
[–] Dangerhart@lemmy.zip 3 points 5 hours ago (1 children)

Does anyone know of rechargeable lithium that can report proportional voltage to emulate what alkaline does? I really want to use rechargeable for everything but not knowing any estimate of when they will die is a huge downside for something like a lock

[–] Landless2029@lemmy.world 2 points 5 hours ago* (last edited 5 hours ago)

They do NOT.

One key benefit of these AAs batteries offer full voltage until they die. They're stepped down to 1.5v from 5v. But any low voltage indicators are based on dropping voltage and don't work with the tech. They just straight up die.

I just stopped using them in things that are time sensitive like my game controller, but I'm fine with an electronic toothbrush or milk foamer using it since they perform better with full voltage.

[–] glimse@lemmy.world 26 points 10 hours ago (3 children)

Hey I haven't used this model specifically but a PSA to anyone with a motorized lock:

If your battery is dying seemingly too fast (and it's not an old battery), your deadbolt is probably misaligned. The friction takes a huge toll on the motor and battery life. They should last MONTHS at minimum.

[–] greatwhitebuffalo41@slrpnk.net 4 points 5 hours ago (1 children)

This is why I haven't replaced mine. There's no real "fixing" this door. It needs to be replaced. That being said if you shoulder check it hard enough it will break open. Ah the fun of inheriting a house that sat vacant for 3 years and had no maintenance for longer than that.

[–] glimse@lemmy.world 3 points 5 hours ago

I take it the frame is busted? If not you might be able to just adjust the hinges. I was amazed when I learned how many door problems can be fixed by shimming and carefully smacking the hinges

load more comments (2 replies)
load more comments
view more: next ›