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Lonely Raven · 8th November 2009

OK, now on to the cutting.

Please note, some of what I do is *very* much not safe. As I post some of these photos, I can imagine "millions of (woodworker) voices suddenly cried out in terror and were suddenly silenced". I'll clarify as we go along here.

First off, I decided to rip all the fins, since this is going to be a well type diffuser along the lines of the RPG OmniFussor, but on a larger scale. Something like this:

Here are my fins cut so far. 3.5" + or - 1/64"

I wound up about 8 fins short! Now, had I done a "cut sheet" where you draw out the panels (in this case 4' X 4') and drawn out each completed piece so I could map out the cuts, I would have made enough fins to complete the project. But I simply started ripping the 3.5" fins and kept going till I reached the required 60 fins, or in this case, ran out of MDF. A little planning might have saved me another trip to the lumber yard. But then again, two full sheets later, and it appears I won't have anything left over for the SECOND diffuser!

Once I had the fins cut, I used some scraps left over from the fins to start building and testing a jig for cutting the 1" tiles for my diffuser. One of my design requirements, was that I try and keep the weight down. So instead of buying 160' of 1" X 1" wood blocks, I'm going to cut 841+ tiles out of MDF, and glue them at the correct height. It sounds harder then it is.

So the concept of the tile cutter, is that I rip the 1/8" MDF scraps into 1" wide strips. Then I feed them into the jig and cut them into 1" X 1" tiles with great consistency. The original jig I made for the band-saw (which is the safest way of cutting objects so small), but my band saw apparently can not cut even a 1" strip straight, and all the tiles came out looking like diamonds. I wound up tossing all those tiles in the trash, and started working on the same jig but for the table saw (the absolutely least safe way of doing this).

Here is the jig on the Table Saw. It's literally the same jig I made for the band saw, but shifted down a bit so the table saw made fresh cuts into the scrap material.

This is the part where woodworkers cry out in anguish. The way this jig works, is that the base panel is glued and stapled to the piece of pine, all very squarely. Then the pine fence is screwed to a quality, very square Miter from Incra. Then I place (staple and glue) a 1" X 1" "stop" exactly 1" to the right of the blade kurf in the jig (see the image above). So I hold onto the long 1" wide strip with my left hand which presses it to the stop, while my right hand index finger holds the (future) 1" tile and the whole jig slides forward into the blade chopping off 1" tiles exactly the same, all day long. (and hopefully not taking any figures with it).

Again, this is absolutely the WRONG way to do this. If the wood binds at all, it could kick up and fling my hand right into the blade. And as sharp and true as this $125 blade it, I probably wouldn't notice till I saw my fingers hit the floor. So do as I say, not as I do!! The *correct* way of doing this would be to make the whole jig more robust, and use a toggle (or two) to hold the MDF in place while I put my hands way back on the fence to push the jig into the blade. Toggles look like this:

You can see how that would be much safer to have the toggle hold the MDF as it's run through the blade. I could come up with 100 excuses why I didn't use a toggle and risk my fingers, but they would all be lame. Just be smart and do it right.

Moving on, a little better view of the whole jig:

And the resulting tiles. These are 1/64" under 1" X 1". I'd say I did pretty good, and I still have all my fingers (So far). I still have a bucket load more of these to cut.

8th November 2009	#2
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 230 Thread Starter	OK, now on to the cutting. Please note, some of what I do is very much not safe. As I post some of these photos, I can imagine "millions of (woodworker) voices suddenly cried out in terror and were suddenly silenced". I'll clarify as we go along here. First off, I decided to rip all the fins, since this is going to be a well type diffuser along the lines of the RPG OmniFussor, but on a larger scale. Something like this: Here are my fins cut so far. 3.5" + or - 1/64" I wound up about 8 fins short! Now, had I done a "cut sheet" where you draw out the panels (in this case 4' X 4') and drawn out each completed piece so I could map out the cuts, I would have made enough fins to complete the project. But I simply started ripping the 3.5" fins and kept going till I reached the required 60 fins, or in this case, ran out of MDF. A little planning might have saved me another trip to the lumber yard. But then again, two full sheets later, and it appears I won't have anything left over for the SECOND diffuser! Once I had the fins cut, I used some scraps left over from the fins to start building and testing a jig for cutting the 1" tiles for my diffuser. One of my design requirements, was that I try and keep the weight down. So instead of buying 160' of 1" X 1" wood blocks, I'm going to cut 841+ tiles out of MDF, and glue them at the correct height. It sounds harder then it is. So the concept of the tile cutter, is that I rip the 1/8" MDF scraps into 1" wide strips. Then I feed them into the jig and cut them into 1" X 1" tiles with great consistency. The original jig I made for the band-saw (which is the safest way of cutting objects so small), but my band saw apparently can not cut even a 1" strip straight, and all the tiles came out looking like diamonds. I wound up tossing all those tiles in the trash, and started working on the same jig but for the table saw (the absolutely least safe way of doing this). Here is the jig on the Table Saw. It's literally the same jig I made for the band saw, but shifted down a bit so the table saw made fresh cuts into the scrap material. This is the part where woodworkers cry out in anguish. The way this jig works, is that the base panel is glued and stapled to the piece of pine, all very squarely. Then the pine fence is screwed to a quality, very square Miter from Incra. Then I place (staple and glue) a 1" X 1" "stop" exactly 1" to the right of the blade kurf in the jig (see the image above). So I hold onto the long 1" wide strip with my left hand which presses it to the stop, while my right hand index finger holds the (future) 1" tile and the whole jig slides forward into the blade chopping off 1" tiles exactly the same, all day long. (and hopefully not taking any figures with it). Again, this is absolutely the WRONG way to do this. If the wood binds at all, it could kick up and fling my hand right into the blade. And as sharp and true as this $125 blade it, I probably wouldn't notice till I saw my fingers hit the floor. So do as I say, not as I do!! The correct way of doing this would be to make the whole jig more robust, and use a toggle (or two) to hold the MDF in place while I put my hands way back on the fence to push the jig into the blade. Toggles look like this: You can see how that would be much safer to have the toggle hold the MDF as it's run through the blade. I could come up with 100 excuses why I didn't use a toggle and risk my fingers, but they would all be lame. Just be smart and do it right. Moving on, a little better view of the whole jig: And the resulting tiles. These are 1/64" under 1" X 1". I'd say I did pretty good, and I still have all my fingers (So far). I still have a bucket load more of these to cut.