Unisaw arbor wear.

[Kent Chasson]

Interesting that another forum has a similar thread going. I suspect there will be more!

The arbor is wearing down (threads have practically disappeared) in the area that dado blade takes up. (.55mm +/-difference in diameter) Still enough thread at the outer end of the arbor, so we are able to mount the dado for 3/4" width. The owner (my boss) has decided to look into having a new one made. I think he made the right call!

I can't see any good reason why that should happen. Sounds like the blades are slipping and the arbor is spinning inside them. That should be noticeable right away when sawing. I would put some more work into figuring out why it's happening before machining a new arbor or buying a new saw. I can't believe it's the fault of the arbor

By the way, I bought an arbor from the "Saw Center" (link above) and it has been fine for several years.

[Jeff Duncan]

Just to clarify, this Delta Unisaw is an "Industrial" machine!!! ... at least it says so on the label on the front of the saw!
I think though, what you are saying is, we should look at another Powermatic 66 or something along that line .... I tend to agree. Which is easy to do since it's not MY money we are talking about.

Delta and industrial should rarely be used in the same sentence They did offer a handful of machines that were heavy.....the Punisaw just wasn't one of them

Now I'm thinking a used Tanny would do the trick Mainly b/c one was for sale locally recently for $400. Only problem is you would need to re-bore your blades for the bigger arbor.

good luck,
JeffD

[Greg Portland]

I can't see any good reason why that should happen. Sounds like the blades are slipping and the arbor is spinning inside them.

+1. How many people work on that machine and do they know the right way to assemble & tighten a dado stack? If the chipper teeth were touching the outer blade teeth then you could end up with a loose blade condition. I can't see where "hardness" is an issue since the parts shouldn't be rubbing against each other.

[hank dekeyser]

Being that their is enough room for it, I would try a brass tube in an effort to protect the threads. If the arbor itself is literally being worn down, it would present itself as run out in the blade and vibration. If you are merely flattening the threads, the brass tube would likely work. Or have a "worn out" arbor you already have machined down to accept a hardened shaft bushing and have a different thread machined on the arbor ? Or heliarc the threaded portion where the (dadoe) blade will be, refresh the bolt threads and have it machined true and harden it? Years back I worked in a shop where we used an old "contractors 9 inch" as a dedicated dadoe machine for tennons and never had an issue with it. They still use it to this day (umm like 25 + years later) Spending the money on a new saw in my mind is silly. but then you didnt really say what you're running through it. my 2 cents