Thinking of building my own power stand for my SS jointer

JPG · Post by **JPG** » Tue Jan 12, 2010 1:22 pm

Power stand / jointer speed. Since the power stand has a smaller motor(1/2 HP) it is better to run at a slower speed(3900). A smooth cut can be obtained, just do not feed so quick(for a good finish even on faster cutters, slow feed = better results).

Adding to the flat/rotary cutter discussion, a larger cutting radius gives a smoother surface(the valleys are shallower and LONGER). Molder vs shaper.

The Mark 5/V runs 3500 RPM at the 'R' setting. This drives the jointer at 5833 RPM.

Thus the SS recommendation of 3900 to 6200(3900 for 1/2 HP power stands and 6200 at R+ on a mark 5/v.

However a 1 1/2 HP motor will be capable of running the jointer at a higher rpm than a 1 1/8 HP motor(Mark 5/V). Assuming a linear speed/load relationship, you may want to design for 8000 RPM.(See below)

A six(6) in motor pulley and a two and one half(2 1/2) in jointer pulley would get you there(8280). No sense in building a test stand for either the motor or the jointer! That oughta be fast enough.

You can adjust the pulley sizes if you feel it needs changing. I would not go much faster though!

In any event, cover/protect the belt!!! Make sure the blades are secure!!!

******After plotting this out, I realized I ignored an offset to the 'linear assumption'. A better goal is 7500 Rpm. A 6 in and 2.75 in would get you 7527 rpm.

SDSSmith · Post by **SDSSmith** » Tue Jan 12, 2010 4:40 pm

billmayo wrote:I use higher rated RPM cutter head bearings when rebuilding any joiner. Most of my personal headstocks can operate the quill at 6000+ RPM when using the joiner (9600 RPM) as I am guilty of feeding the wood faster too.

Okay, I'll bite Bill. How do you get 6000+ RPM out of the quill without a higher speed motor?

bffulgham · Post by **bffulgham** » Tue Jan 12, 2010 5:17 pm

Once again, thanks for everyone's input:) .

Here's a web page I found that will produce all kinds of interesting info depending on pulley sizes and belt length. Thought it would be worthwhile to pass along:
http://www.csgnetwork.com/pulleybeltcalc.html

It took me a bit to figure out how to enter what (I always read the directions....after I give it a shot and foul it up

), but it will even give you center-2-center distances for the shafts depending on belt length. Handy for the design stage.

heathicus · Post by **heathicus** » Tue Jan 12, 2010 5:33 pm

[quote="bffulgham"]Once again, thanks for everyone's input:) .

Here's a web page I found that will produce all kinds of interesting info depending on pulley sizes and belt length. Thought it would be worthwhile to pass along:
http://www.csgnetwork.com/pulleybeltcalc.html

It took me a bit to figure out how to enter what (I always read the directions....after I give it a shot and foul it up ]

Very handy. I used that site when I built the stand for my old Craftsman jointer.

billmayo · Post by **billmayo** » Tue Jan 12, 2010 6:29 pm

SDSSmith wrote:Okay, I'll bite Bill. How do you get 6000+ RPM out of the quill without a higher speed motor?

Very careful and playing with different belt lengths and sizes. I back the high speed adjustment screw out a few turns and using the sanding disk or lathe face plate start turning the quill. I turn the speed control dial slowly past FAST until I hear the control sheave start hitting the speed control bracket/leg. The back off until the control sheave not longer hits and just a tiny bit more. Screw the high speed adjustment screw in until it hits the quadrant and lock the nut on the screw.

Then I check where the belt is operating on the motor sheaves. I play with different belt lengths and sizes including link belts until the top of the belt is riding about 1/8"-3/16" above the outside rim of the motor sheaves. I have been able to get the quill up to 6600 RPM when I was playing with these changes. The reverse is also true. I get a some what lower speed but is restricted by the belt hitting the headstock housing. Since I use my "poor man speed reducer", I did not do any grinding for more belt clearance for lower speeds.

I found that 6000 RPM was fairly easy sometimes by just doing the high speed adjustment. I believe 5200 as the max RPM and is recommended by Shopsmith should apply to all Forum members. Disclaimers now.

Of course, none of this is approved or recommended by Shopsmith. The above information should not apply to or be used by anyone else or attempted by them.

I just love playing with the Shopsmith equipment to see what is possible and make it do/accomplish tasks never intended or discussed before. My second childhood with all the toys and time to play with them. I am truly blessed.