What 3D printing project are you working on today?

[Redbrickman]

PETG would certainly be more robust as it has a little bit of flex in it, however I'm sure it will do the job and if it all goes pear shaped then print another with MK2 enhancements. Even as I write this I can almost hear @The Hat thinking about Johnny 6

 

[Nifty]

Ah Ha, the big question is.. Did you use a metal bolt or a plastic one ?

LOL, It has an embedded nut on one side for a nice fat bolt

Nice design !
If I had to print this part, I'd choose a filament slightly flexible and with good outdoors endurance like PETG or ASA, but given your predilection for PLA, it seems a moot point asking which filament you'll use, isn't ?

Actually, I'm testing the fit in PLA, but I'm going to probably end up printing it in 95A TPU for strength, heat-resistance, and so it will "grab" onto the smooth metal a bit better.

 

[Artur5]

I wouldn't use TPU for heat resistance. It's on a par or worse than PLA.

 

[Redbrickman]

What about printing a strip of TPU maybe 5-6 layers high and glue to the part where it clamps on the bars?

 

[Nifty]

I wouldn't use TPU for heat resistance. It's on a par or worse than PLA.

Fair point on TPU, though from what I’ve seen, its heat resistance is still a bit better than PLA... usually around 60–80°C vs PLA’s 55–60°C. But yeah, it’ll definitely still soften if it’s under pressure in a full sun. I might end up switching to PETG and doing that TPU strip idea.

I think for now I'll test TPU and see how it goes. Also, I even think PLA would work because there is a bit of thermal mass to the part, and my bike is rarely in super-hot situations for long.

 

[The Hat]

I even think PLA would work because there is a bit of thermal mass to the part, and my bike is rarely in super-hot situations for long.

Go with your first idea, PLA will be fine, trust me I’ve been using it for years..

 

[The Hat]

Even as I write this I can almost hear @The Hat thinking about Johnny 6

The mark VI is on the drawing board, and so is a manual old water pump..

 

[Epatcola]

Some lithium rechargeable AAA batteries were delivered today. I want them for things that don't work well on the lower voltage of NiMH cells. I got the type that you just stick 5v across to charge. I have bench power supplies and could get 5v from many USB sources. I needed a holder that would take 4 batteries to charge in parallel.

I designed and printed this

Battery contacts were the problem which I solved with some adhesive copper tape and some 8mm springs I already had. You can see the copper tape for the battery +ve contacts. There is another strip of tape below the springs.

I placed lugs on the side for the tape to wrap around and was going to connect to them with crocodile clips, but, I decided they could chew up the tape too easily so I soldered wires to the tapes and anchored them with some hot melt glue.

I split the thing in two with a dovetail joint so it could be printed without supports and allow the tape to be embedded adhesive side down. Surprisingly the dovetail joint was a nice fit first try and I made it permanent with a bit of superglue.

 

[Nifty]

Some lithium rechargeable AAA batteries were delivered today. I want them for things that don't work well on the lower voltage of NiMH cells. I got the type that you just stick 5v across to charge. I have bench power supplies and could get 5v from many USB sources. I needed a holder that would take 4 batteries to charge in parallel.

I designed and printed this
View attachment 17853
View attachment 17854

Battery contacts were the problem which I solved with some adhesive copper tape and some 8mm springs I already had. You can see the copper tape for the battery +ve contacts. There is another strip of tape below the springs.

I placed lugs on the side for the tape to wrap around and was going to connect to them with crocodile clips, but, I decided they could chew up the tape too easily so I soldered wires to the tapes and anchored them with some hot melt glue.

I split the thing in two with a dovetail joint so it could be printed without supports and allow the tape to be embedded adhesive side down. Surprisingly the dovetail joint was a nice fit first try and I made it permanent with a bit of superglue.

That's fantastic!

I've printed a handful of different battery holders and connectors. Some using stripped wire wrapped around a terminal as the connecting point and just pressure holding the battery in place, and other ones with 3D printed springs pushing the contacts into the batteries.

Next time I do this, I'll probably dig around for some of the springs and contacts that I've pulled out of various electronics. Period. Definitely a better way to go than what I did before.

Your use of springs you had on hand and the copper plate is brilliant.

 

[Epatcola]

Next time I do this, I'll probably dig around for some of the springs and contacts that I've pulled out of various electronics. Period. Definitely a better way to go than what I did before.

I already had this box of springs from Aliexpress. I made the holes they fit in snug so they don't fall out. I had a strange problem with the springs not making electrical contact with the tape. I bent the wire at that end of the spring towards the centre and outwards to make a sort of prong after which contact was fine.