Looks great David! Thanks for sharing the drill chart- I have downloaded it, but in reading it, I can't find reference to 4-40. Is there a trick to finding the small tap sizes we are using? I have never read these types of charts before.
@Katherine Hannaford The screw size is #4. (The 40 is how many threads per inch). By looking at the guide, the drill size on alum. for a 4-40 would be a #43 (tap) #32 (close file) and #30 (Free fit). Make sense? In other words, pick the number from the left hand column marked "Screw Size" (in your case a #4) then read across right to pick thread size then drill bit size.
@Katherine Hannaford Here is my box of Number Bits. The #43 on mine is missing (as well of most of the small bits!) because they are small and I tend to break them! Use a light hand.
HEY EVERYBODY! I'm back in the studio. For those of you in the states, you can get your aluminum (as well as other metals) at Discount Steel www.discountsteel.com . Pretty reasonable prices, will custom cut, nice people and they FedEx. I use them to buy steel for my sculptures.
Dave, This is just a prototype to work everything out. When I build the "real" mechanism, I'll use a more robust U-joint. I wouldn't use the servo city u joint for critical applications.
Gluing in the plate to the skull. Holes tapped and ready to go!
Opted to go with direct drive on the Left/Right head. Getting a nice rotation and movement. All of the weight is carried by the bearings so I'm getting a good speed with the foam skull. If I had a heaver head, I'd either use a bigger servo or get more leverage with what Jim taught.
Comments
Here is my box of Number Bits. The #43 on mine is missing (as well of most of the small bits!) because they are small and I tend to break them! Use a light hand.
/Chris
Opted to go with direct drive on the Left/Right head. Getting a nice rotation and movement. All of the weight is carried by the bearings so I'm getting a good speed with the foam skull. If I had a heaver head, I'd either use a bigger servo or get more leverage with what Jim taught.