2016-11-17 (Th) Clockwork Theremin

Holes in the motor face had already been measured and drilled. A #6 tap was used to complete the holes. The relatively small bolts were chosen since they should have no trouble fitting between the narrow recessed portions of the motor face. Tapping was done with machine oil. Extra care was taken with these motor since the face was aluminum (aluminium) and therefore softer than steel.

Tap wrench in motor face

3/4” #6 bolts had been purchased for this project. After the holes were tapped and blown clear of any chips, bolts were inserted to ensure they would hold. The bolts went in smoothly and held with no more wiggle than would be expected from a machine nut.

Bolts in motor face

A hole saw the size of the motor face couldn’t be found but a large circular hole was needed. The hack space provided a hole cutting bit with an adjustable arm. This adjustable arm allowed for infinitely custom diameters. Since the tolerances weren’t known, a test hole was cut in a scrap piece of hardboard. A second had to be cut when the hole was too large.

Motor in test hole

When the hole cutting drill bit was set to the correct size, the final hole was drilled into the gear board. It was important to keep the new hole centered on the old hole but the exact center had been obliterated before this. The center was estimated and the result was acceptable.

Hole cut in gear board

The modified motor was placed into the cut gear board. Four holes for mounting bolts were drilled where the straps landed. These holes were each marked with a scratch awl, given a pilot hole then drilled from both sides to avoid hole blowout. Ordinary #10 bolts and nuts were used to hold the straps in place.

Motor mounted on gear board

Unfortunately, the motor-mounted gear sat too low to meet the next gear so they don’t mesh. Forunately, it will be easier to raise the motor than to lower it. A space, made from plastic or wood will be cut and drilled to go between the gear board and motor mounts. Washers could be stacked between the gear board and motor mounts but it would more obtrusive.

Gears not meshing

Downloads:
Parts list:

The rest of the posts for this project have been arranged by date.

First time here?


Completed projects from year 1.

Completed projects from year 2.

Completed projects from year 3.


Disclaimer for http://24hourengineer.blogspot.com/

This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

2016-11-15 (Tu)

Comments

Post a Comment