A walk-along circular saw plywood ripper.

[BoyntonStu]

instead?

> When you've built the long handle with a trigger on it, you've built a

The point is not to have to lift heavy plywood sheets.

I have the sheets standing agaist a wall.

I just let one fall over onto the 2x4's. Cut them where they fall.

It takes 2 screws and nuts to mount the plywood plate using 2 holes already in the saw plate.

(Countersunk from below. Also chamfer the front edge for ease of sliding)

No table to build, store, or setup. Just store 4-2x4's.

What advantage is there cutting at 3 feet higher than the floor?

[DanG]

You could buy one sheet of 1 or 2" thick polystyrene or Styrofoam and eliminate the 2x4s. Nice idea.

[else24]

instead?

> > When you've built the long handle with a trigger on it, you've built a

Well, there's your back. And you have to carry the plywood to wherever you store it, so whatever method you use, carrying plywood is part of the process. And you have to bend down and set up the guide. And you have to bend down and set up the saw. And then you have to pick up the pieces. And then you have to pick up the 2x4's. Bend over, bend over, bend over, bend over.

You can tilt the table on its side (as they show in the article you didn't read), lean the plywood against it, and then just tilt it back up. It's easy ans it's simple to set up the guide exactly where I need it.

The advantage to cutting three feet higher than the floor is that you have more control. That's where your eyes and hands, which you use to control the tool, are. That's where it feels most comfortable. Your method sounds much less comfortable.

As I said, you can do it your way. I think it's a single use gadget where the table is multi use, doesn't require modifying the saw, doesn't require unmodifying the saw after I'm done and is safer but if you're happy with it, by all means have fun.

You'll let us know if there's any accidents, right? :-)

As an aside, if either of us got hurt for any reason while we were cutting our plywood, which one of us would have to lie to collect the insurance?

[BoyntonStu]

Neither, but I am willing to bet that keeping feet and hands further away from from the blade is safer than up close.

[Hoosierpopi]

I would like to see pictures of this extension device.

Once, when cutting Hardi Board Siding ( a lot ) I discovered that wet boards (thanks to some inclement weather) cut smoother, quieter and with little or no dust (the dust cutting dry boards with a Skill Saw is phenomenal). So the wife and I formed a cutting team, she spritzing the board in front of the blade from a spray bottle filled with water

- popi cutting with the saw.

Then, with lots more boards to go, I bought some 1/4" polyethylene tubing, a bit of 1/4" copper, a valve to fit between and join the two and a fitting to join the 1/4" poly to the garden hose.

At one end of the copper tubing, i place a small brad nail, then hammered the tubing flat over it before removeing eh nail - forming a nozzle, if you will. Then, I formed the copper alng the fixed blade guard of my older skill saw so that the nozzle end of the tubing could be set to squirt just before the cut and fastened the whole thing to the guard with pop rivets and some wire restraining bits I had laying about,

Now, to cut, I turned on the hose a bit, the opened the little valve and cut.

No dust at all. Smooth, easy cutting with significantly less noise - no more than cutting PT 2 by stock.

Later I heard about mounting the blade backwards and much later saw the four tooth blades sold for this purpose. Bet they'd work better with water added.

Just thought the safety-conscious guys on the list would love this water, power tool, electricity and sharp object combination. Yous, somewhere - I have pictures.

[B A R R Y]

You're probably right on that aspect.

My worry would be more towards the lack of mechanical advantage if a bind were encountered. The spinning blade could jump out of the kerf and go skidding around, ruining an expensive sheet of stock.

It doesn't take much to destroy the .000000001" thick veneer on current cabinet grade ply.

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[BoyntonStu]

Actually there is more of a mechanical advantage due to leverage plus the weight of the operator standing over the extended saw handle.

My plywood is not cabinet grade, it is more like dog-house grade.

[B A R R Y]

I'm not seeing the advantage, unless you're using two hands or have Superman's wrist. Can you post a picture?

Based on the pivot points, a long arm fixed to the saw, held my a short hand, I would see the saw enjoying the mechanical leverage gain.

Think of where the pivot point for a shovel or a wrecking bar is. It's at the opposite end of the stick from your hand

You still don't want to ruin it!

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[BoyntonStu]

Imagine a short handled wheelbarrow,

Compared to a longer one, less torque at the wheel applied by the operator.

[Mike Marlow]

[Swingman]

Grab an eight pound sledge hammer by the handle, 4" from the head, and hold it straight out at arm's length.

Now grab it by the handle 3' from the head and try again.

Can you say: "mechanical disadvantage"? ;)

[Mike Marlow]

Imagine a long flimsy handle on that wheelbarrow. One single long flimsy handle...

[BoyntonStu]

Why imagine long and flimsy?

A 4 foot 2x4 is not long or flimsy.

Imagine 2 crowbars: one 4" long, the other 4 feet long.

Which one applies the most torque?

The hold-down torque is applied about the handle fulcrum point located at the rear of the saw plate.

[Greg Neill]

news: [e-mail]...=

No, the torque is applied at your wrist. You rotate your=20 wrist to rotate the 2x4, supplying the downward force on the saw which is at the end of the 2x4.

Look at it the other way around. If, for whatever reason, the saw wants to jump up, it has the mechanical advantage due to the length of the 2x4 to twist your wrist about its pivot point at the end of your arm.

[Greg O]

No, the torque is applied at your wrist. You rotate your wrist to rotate the 2x4, supplying the downward force on the saw which is at the end of the 2x4.

Look at it the other way around. If, for whatever reason, the saw wants to jump up, it has the mechanical advantage due to the length of the 2x4 to twist your wrist about its pivot point at the end of your arm.

Have a friend come over. Take a 6" long stick in your hand and have your buddy try lever it back and forth in your hand. Now take a 4 foot long stick, hold the end of it, and your buddy on the other end, and have him lever it back and forth, then get back with us on which one takes less effort for you buddy! (in this example your buddy equals the saw!) Greg

[Greg Neill]

I think we're arguing the same side of the argument here, only differing in ascribing where the torque happens and where the resultant force occurs.

Torque occurs about a center of rotation. Torque varies directly with the length of the lever arm. A saw on a stick is asking for trouble.

[Greg O]

Agreeing with you, just to lazy to go back the the OP's post and respond there! Greg

[BoyntonStu]

The stick in my hand is the saw in the slot.

You have it backwards.

Consider a shovel with a short handle to dig a hole? No way.

YOU use the long handle to increase YOUR torque on the shovel head.

In a like manner you use a long handle to keep the saw in the groove.

[Greg Neill]

No, you use the shovel like a lever, with the fulcrum being the edge or side of the hole you're digging. Mechanical advantage then is given by the ratio of the handle length to the length of the shovel face.

When you pick up a load with the shovel, you move one hand down closer to the shovel face to decrease the torque required (the lower hand providing a new fulcrum).

There is no fulcrum to provide a pivot point for the saw on the end of a stick, just what force you can=20 muster by torquing the other end of the stick where you're holding it.

Put a weight on a shovel face and try to lift it while gripping only the shovel handle. Repeat=20 sliding one hand down near the business end. Compare efforts.

[B A R R Y]

I tried that example 15 messages ago, with the bonus of a wrecking bar added for good measure.

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