Using 7 1/4" Table Saw Blade - appropriate?

[reible]

Hi again,

Go down 2 points and see the placement of the riving knife being 1/8" from blade. I don't that can happen either if you have smaller blade.

We also know that the anti-kickback is not effective when 8" diameter blades are used (see page A-3 under the "To Prevent Kickbacks:" point 6). (I think that should also include anything smaller then too).

Remember to read and understand all the safety rules.... or how ever Norm said it.

Ed

[JPG]

Hi again,

Go down 2 points and see the placement of the riving knife being 1/8" from blade. I don't that can happen either if you have smaller blade.

We also know that the anti-kickback is not effective when 8" diameter blades are used (see page A-3 under the "To Prevent Kickbacks:" point 6). (I think that should also include anything smaller then too).

Remember to read and understand all the safety rules.... or how ever Norm said it.

Ed

I assume you are referring to the "Engler" type Norm not the Yankee type.

I plead guilty to not considering the riving knife/anti kick-back pawls in my previous reply. My Goldie did not come with them, and I have survived almost 50 Years without ever considering how to use either one. Yes that means neither a Lower saw guard nor an Upper saw guard! Maybe I will change that once the 510 gets operational!:) BTW the 10E Does have an upper guard and a riving knife - It is about to become 'operational'.

Time will tell if I can tolerate the safety gadgets on them!

[dusty]

The 10E/R used a 8" saw blade with 5/8" arbor.(Magna Engineering)

The Mark 5(Greenies/Goldies/Smooth Gray) used a 9" saw blade with 1 1/4" arbor.(Magna Engineering/Yuba/Magna American)

Mark V uses a 10" saw blade with a 1 1/4" arbor.(Shopsmith Inc.)

Since SS 'approves' using smaller blades distributed by them, I doubt there is a significant safety issue except for the increased(excessive) clearance between the blade and the blade slot etc. Methinks the litigatious(sp?) legal beagles are defining the 'safety rules', not the rational engineering department. Used with a ZCI, I see(IMHO) no safety issue.

I agree with your logic completely; however, I doubt that there is an inherent blessing from Shopsmith since they did not release the 10E/10ERs or the Mark 5s.

Building ZCIs is no problem. Determining the proper speed (safety and quality of cut) for the reduced size blades may be the problem one would face.

[JPG]

. . . Determining the proper speed (safety and quality of cut) for the reduced size blades may be the problem one would face.

Ahh, but the machinery WILL tell!(if you pay attention to it)

[copperhill]

Great info here to consider. I know I learned something just from the back and forth. I bet you old dogs (term used with utmost respect) did too just by considering the various options. I am going to attach it and if it doesn't feel safe then I won't use it. I have a good 10" blade that I will use primarily. The 7 1/4" is a high tooth count that I would only use occasionally.

[a1gutterman]

Great info here to consider. I know I learned something just from the back and forth. I bet you old dogs (term used with utmost respect) did too just by considering the various options. I am going to attach it and if it doesn't feel safe then I won't use it. I have a good 10" blade that I will use primarily. The 7 1/4" is a high tooth count that I would only use occasionally.

IMHO, when you do use the 7 1/4" blade to rip solid woods, you should not use the riving knife/upper guard; your wood might hang up on it. Be more cautious then usual. Using it for crosscutting or to cut plywood and other engineered woods should be okay.

[reible]

[quote="a1gutterman"]IMHO, when you do use the 7 1/4" blade to rip solid woods, you should not use the riving knife/upper guard]

Tim brings up another point, the 7 1/4" blade might be too thin a kerf to even allow for the use of splitter/riving knife and that needs to be checked before you make your first cut....

Ed

[JPG]

I feel a need to mention to all that this thread has an underlying theme of 'Risk Management'.

The 'Safety Rules' in the manuals are to discourage users from deviating from the intended use of the equipment as envisioned by the manufacturer.

Their intent is to minimize the potential for accidental injury(and resultant law suits).

When one DOES deviate, it is at their own risk and they are responsible for properly managing that potential risk. This requires an understanding of why the rules are as they are(as Reible has responsibly pointed out) and what 'new' hazards are presented due to those deviations.

For myself, such journeys are common and pursued with caution. It requires forethought as to what might go wrong before undertaking the task.

If one does not have a like mental awareness of the pitfalls, they are best to not go there.

When dealing with moving parts(machinery) you do need to have a complete understanding of what it does and what it might do under abnormal circumstances(deviations;)).

[copperhill]

Maybe we should all sign a waiver before discussing these things - just kidding. I agree with JPG on this one. For example, everyone knows that a climb cut is potentially dangerous when using a router. However there are times when a person must do at least a short climb cut. When I took my first router class, I recall the instructor beginning by telling everyone how unsafe it was. Later he showed us exactly how to implement a climb cut.

As with any potentially dangerous activity: woodwork, driving, hunting, mowing the grass -- we all must be safe and use caution.

[JPG]

Maybe we should all sign a waiver before discussing these things - just kidding. I agree with JPG on this one. For example, everyone knows that a climb cut is potentially dangerous when using a router. However there are times when a person must do at least a short climb cut. When I took my first router class, I recall the instructor beginning by telling everyone how unsafe it was. Later he showed us exactly how to implement a climb cut.

As with any potentially dangerous activity: woodwork, driving, hunting, mowing the grass -- we all must be safe and use caution.

Mission accomplished!:)