- Joined
- Nov 5, 2016
- Messages
- 1,419
Picked up this Rhodes shaper a few weeks ago and totally stripped it down, cleaned and repaired some issues I found. This machine was converted from a line shaft drive and whoever did it only retrofitted it for a single speed of 70 strokes per minute which is way too fast for a lot of things. I decided I needed to modify it and originally looked into designing/building a step pulley system. The original motor was questionable and I didn't have any of the original flat belt step pulleys so I priced some step pulleys, pillow blocks, shafting, angle iron, plate, jack shaft pulleys, etc.... My ballpark budget estimate was $175-$200. Yeah, maybe I could have gotten some items used or cheaper, but in the end what would I have? A lot of design work, a lot of build work and a bunch of "stuff" hanging off the back end of this little machine. And, I would only have 3 or 4 (depending on the step pulleys I bought) discrete speeds.
So, for $285 total I went the "Cadillac" route. A 3/4HP 3 phase motor with a 1HP VFD. It runs as smooth as can be! From literature I found on-line, it's designed for speeds from 30-95 strokes per minute. I'm getting infinitely variable speeds from 20 to 95 strokes per minute and within the turndown ratio of the motor. It's designed for a 1/2HP motor so I went with 3/4HP for a safety margin while running at lower frequencies.
So now I still have a nice small machine and the convenience and ability to run a wider range of speeds and vary the speed with the spin of a dial!
Above is the new motor mounted the same way the original motor was so I could get some measurements. Notice only two 1/4" bolts right on the casting seam! The original motor bounced all over the place while running like this.
Set it up in my Bridgeport and indicated the drive shaft so I knew alignment was good. Faced off just enough to get a good flat, ~0.050". Drilled and tapped (4) 5/16"-18 holes. I used 3/8" A36 plate for the motor mount using (4) flat countersunk hex head socket cap screws to mount the plate to the cast iron base. Drilled and tapped the plate for (4) 5/16"-18 screws to mount the motor. Turned out to be a very solid setup.
Control box with speed pot and on/off switch.
Motor mount; very solid.
It's a sweet setup! I still need to do some finish up work like add guards, protect the VFD, secure the cables better, etc., but it is functionally done!
Ted
PS: If anyone is looking for a Rhodes shaper, I know where there is one available in central NY.
So, for $285 total I went the "Cadillac" route. A 3/4HP 3 phase motor with a 1HP VFD. It runs as smooth as can be! From literature I found on-line, it's designed for speeds from 30-95 strokes per minute. I'm getting infinitely variable speeds from 20 to 95 strokes per minute and within the turndown ratio of the motor. It's designed for a 1/2HP motor so I went with 3/4HP for a safety margin while running at lower frequencies.
So now I still have a nice small machine and the convenience and ability to run a wider range of speeds and vary the speed with the spin of a dial!
Above is the new motor mounted the same way the original motor was so I could get some measurements. Notice only two 1/4" bolts right on the casting seam! The original motor bounced all over the place while running like this.
Set it up in my Bridgeport and indicated the drive shaft so I knew alignment was good. Faced off just enough to get a good flat, ~0.050". Drilled and tapped (4) 5/16"-18 holes. I used 3/8" A36 plate for the motor mount using (4) flat countersunk hex head socket cap screws to mount the plate to the cast iron base. Drilled and tapped the plate for (4) 5/16"-18 screws to mount the motor. Turned out to be a very solid setup.
Control box with speed pot and on/off switch.
Motor mount; very solid.
It's a sweet setup! I still need to do some finish up work like add guards, protect the VFD, secure the cables better, etc., but it is functionally done!
Ted
PS: If anyone is looking for a Rhodes shaper, I know where there is one available in central NY.
