[Dan Delaney]

So, the saw is cleaning up nicely. It's mostly just thin surface rust.

HOWEVER! The one thing that's not just surface rust is the nut on the motor that holds the blade in place! 🤪 I got all the rust off of the threads in front of the nut, kept putting a bunch of Blaster on it. Keep trying to get it off with just a wrench and with an impact driver. Not budging at all. Tried heating it up with a blow torch several times, still not budging.

Any thoughts on how I might get this off? I'm afraid I might end up having to just cut it off with an angle grinder and get a new nut!

 

[JackDuren]

Maybe let it soak in awhile.

You might have to get a socket and a breaker bar and use a lot of force..

 

[rwe2156]

So, the saw is cleaning up nicely. It's mostly just thin surface rust.

HOWEVER! The one thing that's not just surface rust is the nut on the motor that holds the blade in place! 🤪 I got all the rust off of the threads in front of the nut, kept putting a bunch of Blaster on it. Keep trying to get it off with just a wrench and with an impact driver. Not budging at all. Tried heating it up with a blow torch several times, still not budging.

Any thoughts on how I might get this off? I'm afraid I might end up having to just cut it off with an angle grinder and get a new nut!

Eeks! Not sure I can offer much other than keep heating it, maybe tapping it to break the corrosion. If the shaft gets hot and transmits heat to the bearing......I dunno. I'm sure you've already thought about that.

What I wanted to say is reference to miter cuts. IMO all the radial arms I've owned, I've found it's better to align it at 90 and leave it there. Anytime you change it, you can bet it's not going back to zero.

I've gone to doing miter using a jig and leaving the head at 90. Plus, I can make microadjustments.

That said, a radial arm is not going to replace a miter saw for accuracy, so I have both, plus for the portability.

This is going to relate to your saw, I'm just saying what I've experienced.

 

[aboveboard]

So, the saw is cleaning up nicely. It's mostly just thin surface rust.

HOWEVER! The one thing that's not just surface rust is the nut on the motor that holds the blade in place! 🤪 I got all the rust off of the threads in front of the nut, kept putting a bunch of Blaster on it. Keep trying to get it off with just a wrench and with an impact driver. Not budging at all. Tried heating it up with a blow torch several times, still not budging.

Any thoughts on how I might get this off? I'm afraid I might end up having to just cut it off with an angle grinder and get a new nut!

Before you start cutting the nut with the grinder, is the nut special or proprietary in its threading? Can you easily find a replacement?

My usual trick is to use penetrating lube plus lots of patience. Penetrating lubes include stuff like "liquid wrench". Give it a squirt, give the nut a few small wiggles back and forth without flexing, bending, or stressing the bolt, let it soak overnight, and repeat once a day. For the 70 year old nuts that hold our 70 year old fence in place, it can take up to two weeks of brief tries (really), but I have not failed to unthread one yet.

 

[RClark]

Are you SURE that the nut holding on the blade is right hand thread?

 

[tomsteve]

please don't use an impact driver on that nut. the delta RAS I used to have was left hand thread

 

[MrUnix]

Are you SURE that the nut holding on the blade is right hand thread?

...

please don't use an impact driver on that nut. the delta RAS I used to have was left hand thread

+1

The arbor nut tightens in the opposite direction of blade rotation. Since the blade on a RAS rotates clockwise (when viewed from the left side of the machine), it loosens by turning the nut counter-clockwise.

Cheers,
Brad

 

[JackDuren]

He should only need to look at the threads to show direction..

 

[Straightlines]

...


+1

The arbor nut tightens in the opposite direction of blade rotation. Since the blade on a RAS rotates clockwise (when viewed from the left side of the machine), it loosens by turning the nut counter-clockwise.

Cheers,
Brad

Yes and no. I think you meant to say that it tightens in the counter-clockwise direction and loosens by turning clockwise.

 

[Straightlines]

Just as well? Nah, a VFD will do a MUCH better job than a static phase converter (SPC), or even a rotary phase converter (RPC). The SPC runs the motor unbalanced, which introduces a lot of problems, including increased heat which is the number one enemy of induction motors. It also causes the motor to run at less than full horsepower - typically about 30% less - so a 2hp motor will be turned into one that is only producing less than about 1.25hp. A RPC is an option, but unless you have a lot of three phase machines, it's not worth the expense and hassle IMO.

It used to be that a SPC was the cheapest option to get a 3 phase machine up and running on a single phase circuit. That is no longer the case, as VFD's have steadily been decreasing in costs and increasing features, now in many cases being the most cost effective method for doing so.

Hardest part about using a VFD is where to mount the thing

Cheers,
Brad

Spot on, 100% agreement! You got yourself a good saw and the VFD is the best choice for it for the exact reasons Mr. Unix shared. My 40C is 3-phase and it came with the SPC, which works okay for me simply because the saw is so strong that the loss of one of the 3 legs of power (3-phase has 3 power legs and single-phase has 1) isn’t noticeable on my mostly softwood stock.

If I were to keep the 40C, I would buy a VFD. Not long ago I started researching VFDs and suggest you shop on AliExpress, as they are all made in China or SE Asia. Because they are so broadly used in industrial tooling, warehouse conveyance, CNC, and robotics, they have become a mass-produced commodity, so there aren’t dramatic differences between the various vendors’ products. To correctly size it, you need to contact Delta Technical Service to learn its horsepower and that is the number to use for VFD sizing. For that saw, IIRC a properly sized VFD may be less than $100.

 

[MrUnix]

Yes and no. I think you meant to say that it tightens in the counter-clockwise direction and loosens by turning clockwise.

Dang.. correct. I said it right with the 'tightens opposite the blade rotation' and then said the opposite for loosening Senior moment I guess.

The good thing is that this works for all circular saws. Like on table saws... regardless of being left or right tilt (and hence different thread direction on the arbor nut), they all loosen by putting the wrench on the nut and pulling towards you (same direction as blade travel). All you need to know is which way the blade spins and it works on them all.

Cheers,
Brad

 

[JackDuren]

He just needs to look at the direction of the threads. They are big enough to tell.

 

[Straightlines]

RE the blade guard and blade choices: I have had excellent luck finding needed parts on eBay. You might even be able to find a single-phase motor that is price competitive to a VFD.

Stick with the saw’s prescribed 12” blade, because the motor’s RPM coupled with the larger 12” diameter produce the tooth speed that yields the best cut quality and the needed rotational momentum to maintain proper motor performance.

Blade choice is key to RAS safety. Neutral or negative rake -angle blades are key to reducing kickback and produce better cut quality. Additionally, “triple-chip” blades are required as they include a raker tooth following the angled teeth and this improves swarf clearance and yields flat-bottomed cuts. Common thin kerf ATB blades are not a good option as the rake-angles are far too aggressive. Check the Delphi Forums Radial Arm Saw Forum for their specific blade recommendations that include Forrest and a moderately priced Freud LU83xxxxx (10” version). Having the Freud and Forrest blades, my preference is the Tenryu (12” version IW-30550AB2).

 

[JackDuren]

The parts he is being ill b hard to find on EBay. I look all the time..