Push-Push Cardioid Curve Latch

 

Just made a Cardioid curve push push latch with my new milling machine and drill press. The straightaway is lower than the diagonal path so the pointer can't go up the diagonal, only down it on the return.

Scrap aluminum, wd-40 as cutting fluid. Little Machine Shop manual mill.

Angles milled by just turning the rotating base machine vise and locking it down again for each angle. 

I saw This Old Tony make a similar one (though he used a CNC machine) and figured if I changed the return curve to a properly angled diagonal I could make it with my manual mill. So I did!

There is less friction that way so I could use a weaker spring.

Cardioid = heart-shaped

I did this while avoiding a cardio-workout of snow shoveling.

Happy Valentine's Day 2022!

 Watchmaking Machinery 4: Rotary Table and Indexing Head with Plates

This is a 6" Rotary Table with  a 3-slot plate. Normally 4 slots are better, but I'm using the bore hole. The bore at the center of this takes MT2 (Morse Taper #2) inserts. I have (not arrived yet) an MT2-to-ER32 collet holder. 

Table MT2 > ER32 Collet Holder > ER32 Collet (various sizes) > Mandrel > Blank I'll cut into a gear.

This is one of the division plates. The holes are used to index the rotation of the table to a certain number (or multiple/division of non-Prime numbers). You hand crank this and go one-by-one.

This is a photo of the hand crank. It's in my milling machine because the slot was about 0.8mm too narrow to fit over the shaft it has to mount on. So I milled it larger (0.3mm off one side and about 0.5mm off the other to try and center the slot). I went slow and got it fitted nicely.

The only other issue was the pin that retracts and then pokes into the holes. It was very scratchy and binding. I took it apart, wiped off the thin grease, cleaned out some grit(?) and then it seemed to work 90% better. I think the spring binds a little since the tolerances inside are so tight. I could get (make on my lathe) a different spring but I'll see if this wears in better.

WHAT A PAIN!!! But the table was cheap and shipped (and arrived) in less than 20 hours...during a blizzard! The table rotates buttery-smooth. Totally worth it.

Gear Generator dot com! You can put gears attached to each other on the same axle. Very useful for lunar gear trains.

It was so cold and windy and slushy and snowy that this squirrel came to dry off in the blue jay nest by my side door.