|Project by kiefer||posted 02-10-2014 11:28 PM||4488 views||37 times favorited||36 comments|
I always wanted a indexing device and now that my drill press table is ready to be used I decided to build one .
This is very simple and affordable ,I picked up a 60 tooth sprocket which is a good starting point as every tooth gives me 6 DEG. advance and by making two indexing locators and offsetting them by half a tooth I get 3 DEG. advance .
The sprocket is mounted on a hub and ball bearing which is attached to the plywood base .
There are also four levelers to support the sprocket and level it .A bolt from below thru the centre hub and a nut which is glued to the bolt once adjusted for minimum play hold everything together.
The sprocket is drilled for screws to attach the upper mounting plate which the work piece is attached to with screws or other methods .
The locators are simple dove tail sliding assembly’s and spring loaded with a steel pin to engage into the sprocket tooth .
The complete indexing device is slid into the centre groove of the table and locked in place once set in the proper position by dove tail keys and two socket head bolts .
This is the first test piece and is drilled with a 3/8” bit .
I used the right locator for the outside ring of holes advancing three teeth between holes which is 18 DEG .
advance and while doing this step the left locator was disabled with a clamp .
For the inner ring I disabled the right locator and just played with the advance settings .
Further playing resulted in the three leaf clover on the outer ring ,I felt like a little kid having fun with a new toy .
I think I will find lots of use for this its just fun to play with and more accurate then I expected .
I should be able to produce a fairly large object with this somewhere around 32” diameter .
-- Kiefer 松