Good catch. The rod is 1/2".

Good suggestion Lew.  I now have a 2D drawing in pdf format to send out for quotes.

Hey guys,,,,,,My shaft on my Ridgid motor is 1/2"  diameter, and I have been thinking adding and extension to my shaft, which is the motor shaft I will bet the shaft gets bent out of shape in no time. There is lots of side ways pressure applied when I am sanding with the sleeve sander. Same goes for the 4 x 24" belt sander for when you want to take more off in a hurry you apply way too much pressure to the side of that little shaft......but my shaft is 1/2" so that 1/4" thingy  would be wasted in no time...

My problem with the shaft I have is the top end of the shaft is flat on one side to fit in to a hole made for it which is part of the 4 x 24" belt sander attachment and the threads has a plastic knob on top of a threaded nut inside of the red plastic......From time to time way back yonder the nut gets loose and backs off and causes the shaft to turn just a smidgen where I can't get the 4 x 24" belt sander off the shaft to use the spindle sanding sleeves..

 The part up in the belt sanding hole must be a very light weight metal and gets eaten away and causes lots of trouble... Its my thinking the shaft in that motor is too small to start with and you guys will cause more trouble and faster to have to tear down the whole thing for repairs.

  And this these parts are not available anymore.

Small patch, we have different model sanders. The shaft on mine is 1/2” also, my earlier post incorrectly stated that the extension would be 1/4” dia. The spindle motor shaft is independent of the belt sander and is threaded to the end, no flat.

So how does the shaft keep from spinning if there is not a flat area down past the threads? My red plastic knob up above the threads keeps un screwing and then the flat area twist past the slot then this is where it takes a couple of pry bars to take things apart so I can realign the slot with the slot on the shaft....My model is an EB 4424- 0

   Good luck with what you are doing?

I am probably not the right person to help you.  We don't have the same machine.  I can only describe how my OSS works. The sanding drums are held tight to the shaft by the knob that compresses and expands the drum's diameter slightly when tightened to hold the sanding sleeve tight to the drum.  The knob has left hand threads to keep it from loosening when the shaft rotates.

I have a Ridgid # EB 4424 0 .....But if you guys are going to extend a 1/4" shaft just don't forget the more pressure applied to to the side of the shaft the more saw dust will come off the wood and that should tell a person what to expect..

found this out on woodnet

 

"I called Ridgid support and spoke to Theresa. She provided the following information.

For the old (gray case) model the thread size is 5/16" x 18 tpi - left hand threads

For the newer (orange case) model the thread size 5/16" x 24 tpi - left hand threads"

That’s consistent with the information I received from the machinist that will make the extension for me. Thanks for checking. 

My 4 1/2” spindle sander is now a 6” spindle sander. The shaft extension allows me to use the 6” rubber drums just purchased from Supergrit.

2 minutes ago, Gerry said:

My 4 1/2” spindle sander is now a 6” spindle sander. The shaft extension allows me to use the 6” rubber drums just purchased from Supergrit.

I need to make a trip to Supergrit. Getting low on Mirka discs

I didn’t realize that you could pick up items at the factory 

40 minutes ago, Gerry said:

I didn’t realize that you could pick up items at the factory 

Yes! Great folks there. You can walk around and shop to your hearts content. I always spend way too much money on every trip. Only about 25 miles from here, right outside Gettysburg.

2 hours ago, Gerry said:

My 4 1/2” spindle sander is now a 6” spindle sander. The shaft extension allows me to use the 6” rubber drums just purchased from Supergrit

Very cool Gerry. Glad you were able to get one made that works for your needs. Thanks for taking us along the journey. Hopefully this helps someone else going forward.

Can I ask what did the extension wind up costing? (I understand if you don't want to reveal that.) I saw the earlier post about $100.

Edited April 9, 20241 yr by Fred W. Hargis Jr

Fred, 

I was unable to find anyone else interested in buying one along with me, so I ended up paying $125. The machinist that made it for me has a shop close to where I live. I left the OSS which gave me confidence the part would work as expected.  I had a lower quote from a Chinese firm, but I was uncomfortable that if I made a mistake in the specs I provided I would be out of luck.  Of course there is the additional cost for longer drums and sanding sleeves. Although the total cost of this mod was more than I wanted to spend on a $300 machine, all 6" spindle sanders cost considerably more. 

A total tangent: 

I was swapping blades on my 1980's Unisaw and remembered something when I bought it.  I had been to a seminar by Roger Cliffe on table saws.  He mentioned something about a Ford Pinto and he used that money to buy a Unisaw.  That convinced me that's the direction I should take, and I never for a second regretted it.  However he said, "Don't loose the arbor nut because you'll never find a machinist who can make a left hand acme thread nut."  (not sure why he ever lost it or couldn't get a new one from Delta, but I think of him every time I swap blades.)

I considered several homemade alternatives, but was stymied by the darn left handed threads. It was a non-issue for a machinist.