Lathe countershaft adjustable PTO

Around my WW lathe I don't have a lot of depth to work with in placing and using the motor and the Countershaft. When I acquired a nice little grinding and machining attachment for the cross slide, I had to solve for how to bring a power belt from the countershaft to the pulley on the attachment and make it so it would accommodate all the variable positions and distances I wanted to be able to set the machining head at.

My solution was to create a Power Take off (PTO) pulley system with to moveable and adjustable double pulley heads. This has worked extremely well and it's rather fun to decide where to place the pulleys and at what angles to accommodate position and movement.

The results are below, shown in just one set up configuration

Lathe countershaft adjustable PTO
The angling head and carriage on the smaller set of pulleys is the key to the tremendous variability of the unit. I can quickly find the mean of the angle between the overhead pulley fead and a vertical, horizontal angle on the milling head (or anything in between). The carriage has radial settings and angular settings as well as the shaft it is on adjust rotationally and horizontal angle and vertical height.

Lathe countershaft adjustable PTO head carriage
Net/net, with just a few parts, there is no position I can't quickly feed the belt to and then adjust tension.


Lathe countershaft adjustable PTO
So far, I haven't had to make any auxiliary belts as I can easily take up the tension with the vertical height adjustment of the two large pulleys. These are part of the schaublin countershaft set up that someone was parting out on eBay.

Lathe countershaft adjustable PTO
The Pulleys on the smaller carriage were made by me using the same approach I did for the pinch rollers shown in this same photo.

Lathe countershaft adjustable PTO
Here's a shot of a completely different setup using the variable adjustments of the countershaft PTO. Having the radial adjustments pre and post the lateral pivot on the child arm of the apparatus really enables full alignment even when coming in from an off-angle.
Overarm setup for countershaft PTO on watchmakers lathe milling job

Smooth milling

detail of overarm belt and pully transmission
And here's a third setup sliding the mounting block for the secondary arm down low and running the belting beneath the rollers to achieve a slightly upwards attack angle that is tensioned enough so that when the grinding head moves up and down, the belt remains tensioned. You can see this as work in my page on this blog about face grinding gears using the watchmakers lathe.
Countershaft PTO being used in face grinding setup


2 comments:

  1. I will be sure to capture it in action next time I use it.

    ReplyDelete
  2. I've uploaded and posted a video showing the PTO and countershaft setup at work under the page dedicated to showing the gear face grinding setup. I hope this shows what you were interested in. cheers, Kevin

    ReplyDelete

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