8" Dado blade

[krusty]

I have an 8" Dado Blade, if I purchase the Dado arbor, can I use this blade or is it too large? Thanks.

[dusty]

There is no reason that you can not use it so long as it clears the table insert.

[forrestb]

Keep in mind that the teeth ft/sec will be about ⅓ faster with the 8" blade than with the 6" blade.

You might want to drop the speed down, or be sure that the 8" blade is designed for that ft/sec speed.

Forrest

[Gene Howe]

Forrest is correct. And, it's a bit tricky achieving the correct balance between speed, width of cut and material. Especially on the cuts wider than 5/8.
I spent the $$ and had my 8" ground to produce absolutely flat bottoms or I would give it away or sell it and buy a 6". Which I should have done in the first place.

[jsburger]

Keep in mind that the teeth ft/sec will be about ⅓ faster with the 8" blade than with the 6" blade.

You might want to drop the speed down, or be sure that the 8" blade is designed for that ft/sec speed.

Forrest

While the at is true, in practice I don't think it is a problem if you stay with the SS recommended speed for the 6" dado. The SS recommended speed from the chart is 3500 RPM for both hard and soft wood. The Power Pro speed is 3600 RPM and it does not specify wood type.

If you buy an 8" dado blade it is designed for stand alone tools with probably no thought to the Shopsmith. The arbor speed on my Powermatic PM2000 table saw is 4300RPM. So I don't see any thing to worry about.

Also, correct me if I am wrong, but rotating cutting tools (saw blades, grinding wheels, router bits, etc.) are rated in RPMs not ft/sec.

[jsburger]

OK, I did some more checking. All the SS carbide tip blades I have (the entire set) are rated at 5500 RPM. The old SS branded 6" dado set I have (non-carbide) is rated at 5500 RPM also. So unless you have a Power Pro headstock you can not over speed them on a Shopsmith. The current SS 6" dado set is from CMT and it is rated at 10,200 RPM.

The 10" Forrest Woodworker II I have is rated at 7000 RPM as is an Oldham 10" 80 tooth carbide blade. Given that, I would say your 8" dado set is certainly rated at more than the MK V max speed of 5200 RPM.

Remember in all of the above except for the dado set we are talking 10" blades so I certainly would not worry about using an 8" dado set on a Shopsmith and over speeding it.

Now, you may want to slow it down (or even speed it up) for quality of cut but I am not sure how much that makes a difference. The SS is a variable speed machine but there are not any dedicated table saws in general use that are. Forrest sells 6", 8", 10" and 12" dado sets. They all go on fixed speed table saws. If they didn't all work running at the same speed I am sure there would be a huge cry from the users.

[algale]

OK, I did some more checking. All the SS carbide tip blades I have (the entire set) are rated at 5500 RPM.

You must have the "old" carbide set. I just took delivery of a brand new set and all three say a maximum RPM of 7600 on the box. Here's the photo from Shopsmith. I've drawn a circle around the RPM rating.

555959-1_l.jpg (82.95 KiB) Viewed 9859 times

[reible]

I have an 8" Dado Blade, if I purchase the Dado arbor, can I use this blade or is it too large? Thanks.

I think Dusty pretty much covered the issue but just to make sure....

The blade(s) will have no problem fitting. The table saw insert would work for very thin cuts but in most cases you will need to buy a new saw insert for the dado blade. Since shopsmith sells only the smaller diameter (6") blade the insert is designed with that in mind.

The 8" blade size might be an issue as you try to increase the depth of cut. Either buy or making a blank insert would allow you to cut the insert to fit the larger blade size even at full exposure. You could try to be careful and use the shopsmith version but you will have to watch things.

I personally use an 8" blade size and prefer that for the added depth of cut for times when it is needed. Either deeper cuts or for use with a sled or fixture it come in really handy.

Ed

[jsburger]

OK, I did some more checking. All the SS carbide tip blades I have (the entire set) are rated at 5500 RPM.

You must have the "old" carbide set. I just took delivery of a brand new set and all three say a maximum RPM of 7600 on the box. Here's the photo from Shopsmith. I've drawn a circle around the RPM rating.

555959-1_l.jpg

Yes, I certainly do. The old ones say 5500 on the blade. None of the anti vibration laser cuts in them. So that just further proves the point that speed with an 8" dado set is not an issue on the SS or any other saw for that matter. I think sometimes because we have this great variable speed machine we get worried about over speeding some cutter or something. The SS speed recommendations are for the optimum cutting speed for a given cutter, not the maximum speed that cutter is rated at. I doubt there is anything made today that you can over speed on a standard SS. The Power Pro yes but not the standard head stock.

[BuckeyeDennis]

OK, I did some more checking. All the SS carbide tip blades I have (the entire set) are rated at 5500 RPM.

You must have the "old" carbide set. I just took delivery of a brand new set and all three say a maximum RPM of 7600 on the box. Here's the photo from Shopsmith. I've drawn a circle around the RPM rating.

555959-1_l.jpg

Yes, I certainly do. The old ones say 5500 on the blade. None of the anti vibration laser cuts in them. So that just further proves the point that speed with an 8" dado set is not an issue on the SS or any other saw for that matter. I think sometimes because we have this great variable speed machine we get worried about over speeding some cutter or something. The SS speed recommendations are for the optimum cutting speed for a given cutter, not the maximum speed that cutter is rated at. I doubt there is anything made today that you can over speed on a standard SS. The Power Pro yes but not the standard head stock.

Well you obviously don't own one of these guys:
http://www.amazon.com/General-Tools-Ins ... B00004T7P1

I like mine. But at max cutting diameter, even running at low speed with a speed reducer makes me want a guard the size of a cake cover!