Well, this is my first official blog entry on LJ’s. I’ve meant to do some blogging of my restorations here, in part so I can post more pictures (without overly cluttering some of the restoration/”of your dreams” threads) and so I can go more in depth when I feel the need or desire. I recently posted a restoration I did of a Millers Falls No 85 breast drill over in the Show the restoration thread.
According to OldToolHeaven the No 85 was made for 11 years from 1912 to 1922. Following the information there I assume mine to be made from 1915-22.
Here is a quick before and after of it:
One of the really neat things about this two-speed drill is the manner in which the speeds are changed. It uses a very simple and interesting speed adjustment lever. I had a few LJ’s ask about it so I figured I could post some pictures of how it works, it’s various parts and how they go together. Hopefully with this I can sate the curious and also preserve for posterity the drills inner workings for those who may be restoring/fixing one of their own.
The gears are actually two within one. Here you can see how both the slow and fast speed drive gears engage the drill shaft simultaneously:
The speed change is made using the speed change lever (here, currently “in” for the smaller fast speed gear):
It has a spring to keep its rest state as pushing down into the gears. To make it the high speed, you push the lever down and in. Once pushed fully in, let go and give the handle a slow turn. The spring will cause the lever to push down and eventually engage the teeth of the fast speed gear. Slow/high-torque is the opposite: push down and pull out as far as it will go. Let go, give the handle a slow spin and the speed lever will eventually engage the larger drive plates’s teeth.
The handle assembly sits within/around the two gears. A cut out in the handle assembly is where the single tooth of the speed lever is given clearance to engage the drive gear teeth of either drive plate, depending on position of the lever
The drive wheels are actually two drive gears, the fast speed gear sitting within the higher-torque low speed gear
A shot of the speed lever’s individual parts, mine was missing a pin that allows the bottom two pieces to pivot on so I fashioned a new one using hardened “music wire” of an appropriate diameter.
The spring in my 85 was broken beyond repair as well, so I substituted a spring from a ballpoint pen. The wire is slightly smaller in gauge so time will tell if it holds up well or will need replacing.
A few more parting pictures of the gear drive disassembled
So there ya go: the Millers Falls No 85 2 speed quick change breast drill. This also has a cousin, the No 95, the only difference being the 85 has spring type alligator jaws while the 95 has a three tooth chuck.
I hope to bring more to this series, general old tool musings, restorations and perhaps some more in depth explanations as well as some disassembly information for those looking at restoring their own old tools.
Thank you for tuning in,
-- Jake -- "Not only do we live among the stars, the stars live within us." - Neil Degrasse Tyson