Digital Bird Focus Motor- Mark III

This is mark3 of the DIgital bird focus motor designed to work with any of the Digital Bird 3D printable Pan Tilt heads.

This new design is slimer, simpler to build and has more torque than the previous models largely down to its new 1 to 4.4 gear set. If you have built one of the previous models you can re-use the main control board but you will need to purchase a new motor since this model uses the motor support tabs we removed on earlier versions! Sorry

Functionally it works just the same as previous versions but is more capable of moving those stubborn heavy zoom rings on larger photography lenses and has as slim a profile as the motor will allow.

As before there are Left and right hand versions of the parts so you can build the versions which suit your particular camera setup. My Sony A7iii setup for example requires one on each side of the lense for focus and zoom so I use one LH one RH.

Note: There should be no problem using this new design along side earlier versions you may have already built.

This focus motor has been designed to work with the Digital Bird 3D printable Motion control system. It has not been designed to work with any other system or software. However since the design utilises a TMS2209 stepper driver and AS5600 encoder it could be readily adaptable to your own software applications.

As before you can purchase a kits here: Focus Motor Kit

The kits with or without the 3D printed parts and include everything you will require to build the device including motor, gears, driver board , connection cable, screws and fittings. The motor is now provided with the gears already fitted and ready to drop into place.

Notes for Upgraders only

If you are upgrading from an earlier version using your original control board you will need the following:

• 1x M3x12mm slotted shoulder bolt with 6mm diameter shoulder
• 2x M3 washers
• 1x M6 washer
• 2x M3 Nut
• 1x M3x20mm cap head bolt
• 2x M2.5 x 20mm cap head bolts
• 1x Brass/copper 10T 0.8mod gear 5mm bore
• 1x 6x12x4 bearing
• 1x Round Nema 14 Bipolar 0.9deg 8Ncm(11.33oz.in) 0.65A ��36x19.6mm 4 Wires

You will need to bore two new 2.5mm holes through your control board for the revised back screw positions and remove approximately 5mm from your motor shaft length. You will not be able to use your old motor with this design since the previous design removed the motor mounting tabs which we are now using to support the large gear. Remember also to remove the encoder magnet from the back of your old motor and position it on the new one.

• Decide whether you are building a Left hand or Right hand motor and print only the parts you require. As always with my designs the second part of the part number is the recommended fill so 001-80 is 80% fill. You do not need to print part 005-100 The 44T gear unless you are upgrading from the older kit.
• Take your M5 brass insert and using a soldering iron melt it into the hole in part 001-80 as shown. Clear away any plastic residue from the inner thread while still hot. Make sure your adjustable wing bolt engages with the threaded insert.

• Make sure you have a good fit between parts 001-80 and 002-40 and superglue the two parts together as shown.

If you are upgrading see step 7

• Install your motor and gear assembly into the top of part 002-40 being careful to ensure the motor cable aligns with the small slot in the part so as not to damage the cables.

• Position your front cap piece part 003-25 then from the inside of part 001-80 drive home your M3 x16mm cap head screw until it threads with the motor mounting tab and up into the cover cap

• Install your control board plugging in your motor cable into the 4 pin socket provided making sure your control board sits flush with the top of part 001-80

• Install the back plate part 004-80 and drive home the two M2.5mm bolts through the control board and into part 001-80.

Motor and gear preparation for Upgraders only

• Prepare your Nema 14 motor by first removing approx 5mm from the end of the motor shaft so that your 8mm deep brass bear is flush with the end of the shaft with the base of the gear approx 1mm away from the face of the motor. So the shaft should end up no more than 10mm long.
• With a metal file add a small amount of chamfer to the end of the cut shaft so the brass gear has a good start on the shaft.
• Place the motor and the gear in a vice and press fit the gear to the motor shaft.
• Press fit your 6x12x4 bearing into the Plastic 44T gear part 005-100 until it is all the way home. I use a small vice for this and add a couple of washers between the bearing andthe vice for the last push to ensure it is all the way home bellow the top surface of the gear. Note I print my large gear at 70% of my normal print speed for best results.
• Add a M6 washer to the end of your Shoulder bolt and drop the shoulder bolt into bearing. Note the shoulder bolt goes through the side of the gear with the smaller hole not the side you pushed the bearing in through.
• Add the two small M3 washers to the other side of the bolt and lock down with the M3 Nut . The Gear should be running free on the bearing.
• Install the gear on the motor by screwing it down through the hole in the motor fixing tab. If you wish you can add some thread lock to the end of the screw. DO NOT OVER TIGHTEN THIS SCREW AS THE MOTOR CASING IS ONLY ALUMINIUM AND YOU COULD STRIP THE THREAD!
• Install your encoder magnet on the back of the motor shaft with a very small spot of superglue. Shorten the Motor cables as required and add a JST 4 pin connector.
• Follow the assembly instruction above.