8" dado set?

[djg]

I have a Mark V model 500. Shopsmith only sells a 6" dado set.
Is it safe to use an 8" dado set on my Shopsmith?
Thanks.

[mountainbreeze]

The only dado set I have ever used on my Shopsmith is an 8" set. Works fine.

[garys]

I have had both a 6" and an 8" dado that I've used on my Shopsmith. I don't know of any reason it isn't safe.

[djg]

Thanks much!

[reible]

You will want to make your own table insert if you plan to take advantage of the larger blade size. The shopsmith version is designed for the smaller diameter blades.

Ed

[djg]

Hadn't thought of that. Thanks!

[Chad]

download (1).jpg (12.17 KiB) Viewed 3303 times

Watch it here: https://www.youtube.com/watch?v=ioyobsgaYUA

James Hamilton (Stumpy Nubs) gives some great information in this video. It's only 3:32 long. Well worth your time.

Should you use a 6, an 8 or a 10-inch set?
When you use this link to visit our sponsor, you support us►
Ridge Carbide Dado Sets (Use coupon code SNWJ10): https://goo.gl/z8TP0k

Video about setting up a Dado set: https://www.youtube.com/watch?v=KPYXU...
What to look for in a good dado set: https://www.youtube.com/watch?v=Ex4Ug...

Subscribe (free) to Stumpy Nubs Woodworking Journal e-Magazine► http://www.stumpynubs.com/subscribe.html

Follow us on social media►
Instagram: https://www.instagram.com/stumpynubs/
Twitter: https://twitter.com/StumpyNubs
Facebook: https://www.facebook.com/Stumpy-Nubs-...

[StevenAyres]

It's apparent that Shopsmith chose blade diameters primarily in consideration of available torque. Older models with less power are sized for 9" cutting blades, younger for 10". The much larger cutting face of a dado takes a lot more torque than a cutting blade, so you'll always use dado sets that are smaller than your cutting blades.

[BuckeyeDennis]

It's apparent that Shopsmith chose blade diameters primarily in consideration of available torque. Older models with less power are sized for 9" cutting blades, younger for 10". The much larger cutting face of a dado takes a lot more torque than a cutting blade, so you'll always use dado sets that are smaller than your cutting blades.

This is indeed the case for conventional table saws. But when it comes to blade compatibility, a Shopsmith has a distinct advantage over conventional saws. The variable-speed Reeves drive in the headstock is quite literally a variable-speed transmission. So if you reduce the blade speed, you also increase the available blade torque, in direct proportion.

If you want or need to use a larger-diameter blade, or to make a heavier rip cut, you can crank the speed down. Which unless a drive belt slips, is synonomous with cranking the blade torque up. That’s not exactly a substitute for a more powerful motor, though. If you have to reduce the blade speed, you will have to reduce your feed rate commensurately. But an 8” dado stack, running at 75% of the rpm of a 6” stack, will have the same tooth velocity. And be capable of the same feed rate, everything else being equal.

I’d argue that the extra width of a dado stack is the reason that the “dado” setting on a Shopsmith speed dial is a lower speed than the “saw-joint” setting. The smaller diameter does reduce the blade torque requirement. But in the case of a wide stack, not by enough.

I consider the settings on the Shopsmith speed dial to be just approximations of the ideal speed. You can vary the speed as needed to best match the operation at hand. Which is also quite useful for reducing “burning” when cutting wood. I cut quite a bit of cherry, which burns easily. But if I get burning at the “saw-joint” setting, and everything is sharp, clean, and aligned, I just crank down the speed until it goes away. End of problem.

[dms8667]

Nice summary!