saw arbors

rdavidp · Post by **rdavidp** » Sun Nov 18, 2012 4:27 pm

There are two saw arbors for the Shopsmith. Note that I have the 500 style saw table. There is a 1 1/4" and a 5/8" arbor. The 5/8" arbor accepts most other saw blades, but not the Shopsmith made blades, nor can it take a dado. The 1 1/4" arbor is used for Shopsmith made blades. Other than those differences, are there any other pros/cons between the two sizes?

JPG · Post by **JPG** » Sun Nov 18, 2012 4:55 pm

There are several 'versions' over the years.

There are two significant 1 1/4" arbors. A shorter one for earlier Mark 5 and Mark V 500. The longer ones are for the models with larger tables (505/510/520). There are variants among the longer ones.

The 5/8" arbors are intended for blades with 5/8" arbor holes, regardless of who made/sold them(ss included).

An additional 5/8" arbor has a longer threaded shaft with different spacing 'washers' that is intended for dado blade sets. Even that one has 'variants'.

A point to keep in mind is that the saw arbors are designed to be driven only one direction. The locking nut will be pushed in the tighten direction(left hand thread on quill side and right hand thread on the out side).

Another arbor type is intended for general purpose or saw blade arbor use and it includes a keyed washer so as to allow running either direction etc.

As a side note, this is all well and good when induction motors are used.

The Power Pro with it's constant speed 'regulation' and braking at power off requires very securely tightened arbor nuts! Coasting saw blades are the result of insufficient nut tightening.

dusty · Post by **dusty** » Sun Nov 18, 2012 5:53 pm

If one pays attention to where the blade is located and uses the quill to properly position it - is it safe to use any of the Shopsmith arbors on a Mark 5/V?

JPG · Post by **JPG** » Sun Nov 18, 2012 7:43 pm

dusty wrote:If one pays attention to where the blade is located and uses the quill to properly position it - is it safe to use any of the Shopsmith arbors on a Mark 5/V?

Previous thread has discussed that. Opinions differ. The keyed washer is a positive factor, but I believe they all could be 'safely' used as saw arbors as long as the saw blade under load torqued the lock nuts 'tighter'.

reible · Post by **reible** » Sun Nov 18, 2012 8:33 pm

Hi,

If you plan on using saw shopsmith guards, and splitters and I personally recommend doing so, you will need to get the proper blade arbors.

Ed

dgale · Post by **dgale** » Sun Nov 18, 2012 9:22 pm

JPG40504 wrote:There are several 'versions' over the years.

A point to keep in mind is that the saw arbors are designed to be driven only one direction. The locking nut will be pushed in the tighten direction(left hand thread on quill side and right hand thread on the out side).

I'm confused about this part - are you saying they make two types of each size arbor - normal (right hand) threads for the quill side and also ones with reverse threads for the opposite (accessory) side? I was unaware that the arbor came with different thread directions and checking the SS website, I don't see them selling them this way (?).

rdavidp · Post by **rdavidp** » Sun Nov 18, 2012 9:30 pm

Only thing I see the SS website selling is a 1 1/4" and 5/8" arbor for the 500, and a 1 1/4" and a 5/8" for the 510/520. Since my 1985 Mark V is a 500, it only makes sense to me to purchase the 1 1/4" or the 5/8" arbor for the 500. I guess my question comes down to out of these two sizes, 1 1/4" and 5/8", is there an advantage of one size over the other?

dgale · Post by **dgale** » Sun Nov 18, 2012 9:38 pm

rdavidp wrote:Only thing I see the SS website selling is a 1 1/4" and 5/8" arbor for the 500, and a 1 1/4" and a 5/8" for the 510/520. Since my 1985 Mark V is a 500, it only makes sense to me to purchase the 1 1/4" or the 5/8" arbor for the 500. I guess my question comes down to out of these two sizes, 1 1/4" and 5/8", is there an advantage of one size over the other?

Just depends on what saw blades you have or plan to buy to use with your SS - the only difference is the size of the arbor (and hence the size of the arbor hole on your saw blades). If you have blades with 5/8" arbor holes, you need the 5/8" arbor, and if you have SS blades with the 1-1/4" arbor hole, you need the 12-1/4" arbor. If you plan to switch blades with any frequency, it's convenient to have an arbor on each of your blades so you can swap from one to another quickly...otherwise you need to remove the arbor from one blade and reinstall it on the next blade you want to use.

JPG · Post by **JPG** » Sun Nov 18, 2012 10:19 pm

SS has maintained the 1 1/4" arbor hole is preferable. Blade stabilizers are less likely to be needed, the larger arbor grips the blade better.

Left hand/right hand nuts are not an option in itself, but are merely a design decision. The older Mark 5 arbors were all designed with the nut on the quill side. That allows a hard stop or lip that makes it impossible for the blade to become separated from the arbor when mounted on the quill. A nut on the outside creates the possibility of the blade sliding off the arbor with a loose/missing nut.