Post by wader on Nov 6, 2017 16:52:45 GMT -5
I've had a request for details on my sphere machine. It might take a bit to get enough pics and measurements, but here's a start. I'll update when I can.
I started with 3/4" piece of plywood, cut a 36" circle out and layed out the three heads at 120 degrees. I had an old aluminum saw guide/straight edge that had a piece that slid in to connect them. I cut three pieces of the guide at about 16", and three pieces of the connection piece(about 8" each). I screwed the guide part on each of the three head locations.
I had a few pieces of Ironwood decking that I used for the carriage cut to 12". I cut a 3" piece and screwed it to the front of the carriage to gain some height and better purchase for the hinge screws. I drilled a 3/8" hole through the block to allow for the carriage feed rod. I attached the connection piece of the guide to the bottom of the carriage and added a strip of Ironwood to stabilize the carriage.
I made a threaded bracket that mounted at the back of the carriage for the feed, and a bracket at the front on the table with a double nut/washer/bracket/washer/locknut assembly. The carriage feed is a really great feature and saves a lot of headaches.
I made the motor/arbor box out of 3/4" plywood. Base, 8"x12". Side, 12"x12". Front, 8"x12". I cut three 18" pieces of 5/8x11 threaded rod for the arbor. I got the six 5/8" pillow blocks from a local store, mounted them flush to the top and as far apart as I could. Put the rod though the blocks to mark the hole on the front and drilled it out. I drilled two holes for 1/4" bolts at the back to land on the carriage and used some stiff springs for the tension on the heads. I find this a better option than the bungee cords on the top as it provides a more consistent and unobtrusive pressure.
I used three 5" bearing hinges for use on steel/heavy doors. I found these had little to no lateral play which is essential for alignment. Attaching the hinges was a bit tricky to make sure everything lined up. The arbor needs to be centred on the layout. I used a 3" wedge of Ironwood under the hinge to allow the head to tilt back with applied pressure.
I used t- nuts on the underside of the motor mount after postponing the motor to fit the v-belt. I used an 1-1/2" drive, and 6" driven pulley for a 1:4 reduction. 1725 rpm down to about 430 rpm. The motors are 1/4 Hp furnace blower motors and can be found just about anywhere for cheap. An 8" driven pulley would bring it down to 325 rpm.
Ill have to make a part 2 for more pics.
I started with 3/4" piece of plywood, cut a 36" circle out and layed out the three heads at 120 degrees. I had an old aluminum saw guide/straight edge that had a piece that slid in to connect them. I cut three pieces of the guide at about 16", and three pieces of the connection piece(about 8" each). I screwed the guide part on each of the three head locations.
I had a few pieces of Ironwood decking that I used for the carriage cut to 12". I cut a 3" piece and screwed it to the front of the carriage to gain some height and better purchase for the hinge screws. I drilled a 3/8" hole through the block to allow for the carriage feed rod. I attached the connection piece of the guide to the bottom of the carriage and added a strip of Ironwood to stabilize the carriage.
I made a threaded bracket that mounted at the back of the carriage for the feed, and a bracket at the front on the table with a double nut/washer/bracket/washer/locknut assembly. The carriage feed is a really great feature and saves a lot of headaches.
I made the motor/arbor box out of 3/4" plywood. Base, 8"x12". Side, 12"x12". Front, 8"x12". I cut three 18" pieces of 5/8x11 threaded rod for the arbor. I got the six 5/8" pillow blocks from a local store, mounted them flush to the top and as far apart as I could. Put the rod though the blocks to mark the hole on the front and drilled it out. I drilled two holes for 1/4" bolts at the back to land on the carriage and used some stiff springs for the tension on the heads. I find this a better option than the bungee cords on the top as it provides a more consistent and unobtrusive pressure.
I used three 5" bearing hinges for use on steel/heavy doors. I found these had little to no lateral play which is essential for alignment. Attaching the hinges was a bit tricky to make sure everything lined up. The arbor needs to be centred on the layout. I used a 3" wedge of Ironwood under the hinge to allow the head to tilt back with applied pressure.
I used t- nuts on the underside of the motor mount after postponing the motor to fit the v-belt. I used an 1-1/2" drive, and 6" driven pulley for a 1:4 reduction. 1725 rpm down to about 430 rpm. The motors are 1/4 Hp furnace blower motors and can be found just about anywhere for cheap. An 8" driven pulley would bring it down to 325 rpm.
Ill have to make a part 2 for more pics.
