My Clock Build Project Thread

Made the click out of 4140 which engages the ratchet.

I used my CNC mill to make this part. This simple part tool much longer than expected. I first drilled and tapped the fixture plate made from Aluminum. Not moving the mill table, I superglued the stock down and drilled the clearance hole, place a screw to help hold it. I took shallow passes, but it moved on the last pass and had to start again.
IMG_6447.jpg

On the second attempt, success! It didn't move.
IMG_6449.jpg

Completed part next to ratchet, barrel, front cap.
IMG_6453.jpg
 
Next, I need to make the click spring which holds the click against the ratchet.

This could be interesting since the part is so thin. I might try super glue again and keep my fingers crossed it stays in place while CNC-ing it.

I watched clickspring on YT make his and he used a scroll saw, belt sander, and files to bring this piece to shape. I'm not sure I have his skills, but if the above method doesn't work, I'll have to give it a try.

Here's the part:
Clickspring.jpeg
 
A hand piercing saw is surprisingly capable of cutting O1 steel. And new files do wonders in metal removal. I use Grobet-Vallorbe swiss pattern files and draw filing strokes to finish.

At least you have 2 holes this time to hold to fixture.
 
devils4ever said:
Next, I need to make the click spring which holds the click against the ratchet.

This could be interesting since the part is so thin. I might try super glue again and keep my fingers crossed it stays in place while CNC-ing it.

I watched clickspring on YT make his and he used a scroll saw, belt sander, and files to bring this piece to shape. I'm not sure I have his skills, but if the above method doesn't work, I'll have to give it a try.

Here's the part:
View attachment 446794
Click to expand...
That is an interesting part. I am wondering, not a pro, just thinking... Cut the inner radius out and leave extra on the outer radius to refinished on a small belt grinder... Wow, a clock is on my list and this looks very interesting.
 
devils4ever said:
Next, I need to make the click spring which holds the click against the ratchet.

This could be interesting since the part is so thin. I might try super glue again and keep my fingers crossed it stays in place while CNC-ing it.
Click to expand...
I find workholding to be a common problem with my CNC projects. I've had good luck using double-sided carpet tape for engraving & drilling operations but haven't tried it for actual machining.

If your super glue doesn't hold, maybe try a thicker piece of stock and cut it off the billet after the fact? I'm thinking if it's 1/4" tall, use 1/2" stock and machine 3/8" deep. Then use a slitting saw to cut the 1/4" piece off the billet.

Or, if it's 1/4" tall cut to 0.220" deep leaving a little of the stock behind. Then needle file the 0.030" stock back to your machined surface?

Yet one more thought is adding a temporary boss like the crappy sketch below that's removed after the fact? Start by drilling the holes, screw the blank down using those. Then machine the path and cut the tab/boss off after? It'd be essentially cutting the gates/vent off a cast part.

1683218585035.png

Bruce
 
All interesting ideas. I can have the FreeCAD tools leave little "tabs" on the profile. It works okay most of the time. It creates a ramp on the upwards side and downwards side on various places on the part. The downwards side cause the issue. The end mill doesn't like coming downhill even though it's a center cutting end mill. I prefer not doing this since it also requires cleanup afterwards to remove these tabs.

Yes, 2 screws to hold it down will help, but I'm worried about the long slender end flexing during machining.
 
You could also put the "tab" (I know, you don't like them) on the end of the part rather than one of the sides. Whether that would be more or less difficult to clean up I'm not sure but it might support that floppy end better.
 
francist said:
You could also put the "tab" (I know, you don't like them) on the end of the part rather than one of the sides. Whether that would be more or less difficult to clean up I'm not sure but it might support that floppy end better.
Click to expand...
That is a good idea, right at the end leave a bulb and you could put an additional hole for hold down then just cut it off...
 
Yes, that was what I was thinking. Don't know if that makes it easier to remove or not but it saves trying to get the back nice and clean again. Personally I would cut and file it by hand, but I don't have CNC anyway so no choice in the matter!
 
devils4ever said:
All interesting ideas. I can have the FreeCAD tools leave little "tabs" on the profile. It works okay most of the time. It creates a ramp on the upwards side and downwards side on various places on the part. The downwards side cause the issue. The end mill doesn't like coming downhill even though it's a center cutting end mill. I prefer not doing this since it also requires cleanup afterwards to remove these tabs.

Yes, 2 screws to hold it down will help, but I'm worried about the long slender end flexing during machining.
Click to expand...
Where did you find your plans? did you design the clock yourself or use an existing design?
 
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