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bumpnstump
01-26-2013, 10:28 PM
For Christmas this year, I bought one of the Ridgid Fuego 6 1/2" corded saws. My intent was to rig it up on the EZ track for cutting. With 2" of cut depth before changing the base, and with 1 1/4" after rigging up a base for the track, I was enjoying the light weight and the smaller ergonomics for my smallish hands. And, spinning at 6100 rpm using a Diablo blade, I was getting some fairly decent cuts.

Then, I thought I'd just rout out the composite base on this saw to pick up another 1/4" of cutting depth. But before experimenting on the original base, I went to the tool repair guy in my area and picked up a free aluminum base off of a PC saw. Figured I'd experiment on the 'trash' base first, before modifying the original base.

Well, I got to thinking about it, and decided to try my hand at rigging up some sort of an affair like the 'big' boys do, and make this base to be able to index the same cut line at 90˚ as well as any degree up thru 45˚.
I did a few sketches, some mock-ups/samples and decided to have a go at it.

Utilizing some simple jigs and my small palm router, I finally cobbled together the saw contraption you see in pic 1.
Pic two shows three cuts: top one is my first 90/45 cut after putting it all together. The stair step difference between the 90˚ and the 45˚ is exactly 1/16".
The middle cut is after a bit of tweaking- ~1/32" off; the bottom cut is final tweak.
Pic three shows some cuts from the end view.
The cut lines are <1/64" off, max.

Like most of what I make, the saw looks like a Frankenstein creation, but it does work. Got a few 'clean-up' items to do on it, and it'll be good to go.
On the EZ track, it cuts 1 1/2" deep at 90˚; 15/16" deep at 45˚; off track, I get 2" depth at 90˚.

So, if some of you guys need this feature, you can probably make one quicker and better than I did; once the 'math' was figured out, it was just a matter of making it.
Rick

tofu
01-26-2013, 11:52 PM
Rick, great work:cool:

-Christopher

Lex
01-27-2013, 12:05 PM
Great work as always, Rick. I'm assuming that the design goal is to get the pivot point directly in line with the center of the saw blade? If so, does the saw always have to be at max depth for accurate bevels (or in other words, does the bevel cut line not align with the 90-degree cut line at shallow depths of cut?)

Dik Harrison
01-27-2013, 12:39 PM
Hint: Make the pivot point the cut-line and you get same cut-line with any bevel setting.

bumpnstump
01-27-2013, 12:59 PM
Great work as always, Rick. I'm assuming that the design goal is to get the pivot point directly in line with the center of the saw blade? If so, does the saw always have to be at max depth for accurate bevels (or in other words, does the bevel cut line not align with the 90-degree cut line at shallow depths of cut?)

Lex, I actually wanted the cut lines to be indexed off of the left side of the saw blade instead of the middle of the saw blade. The thinking here is that if someone is using track with the Anti-chip-edge (ACE), the edge of the ACE would be the cut line.
The way I built this thing, the cut lines are aligned no matter what the depth of cut, and no matter what angle you set.
Basically, it's just a matter of plotting points on a graph:
-cut point (for any degree) will always be fixed;
-to achieve that fixed cut point, the saw will need to slide to the right (parallel to the base- see pic one in my first post) as it is heeled over to make an angle cut;
-then, to keep everything moving smoothly and accurately during the movement, some sort of 'guide pins' are necessary to keep everything lined up as the saw is moving horizontally to the right. (in pic one of the original post, the curved slots are where the guide pins slide.)

This pic shows the little jig I came up with to make all of the sliding/indexing parts.
On the left in the pic is the adaptation to the bottom of the palm router that routs the curved parts; on the right in the pic is the actual routing jig. (The horiz. slots on the HDPE were initially routed using the SSRK) On the bottom of the modified router base, you can see a) the hole for the 1/4" router bit to come thru, b) the index pin that will ride in the horiz. slot of the HDPE, and c) a 'leg' on the base. The inner part of this 'leg' represents the left side of the saw blade.
To use the jig, insert the indexing pin on the router into the horiz. slot on the HDPE while pushing the 'leg' up against the wire 'dowel' sticking up thru the routing jig. Then, when you turn on the router and lower the bit into the HDPE, you'll a) maintain constant contact with the 'leg' against the wire 'dowel', and, b) pull the indexing pin along the horiz. slot in the HDPE. The result will be the curved slot. For greater stability, I routed double curved slots (one at 2 1/2" from horiz. centerline; the other at 1 3/4" centerline); if you're careful, you could probably get by with one curved slot.

Doing this procedure keeps the center-line distance of the pin in the horiz. slot always exactly in line with the center-line of the curved slots, and, it all rotates around the cut line.
Probably the most important measurement is the distance from the desired cut point, to the center-line of the horizontal slide slot, which is: distance from centerline of horiz. slot to bottom of HDPE, added to the thickness of the saw base the HDPE will be attached to, added to the thickness of the EZ track (1/2"). You can see in pic two of my original post that I missed this a bit and had to 'tweak' everything to get it to work. I 'tweaked' it by adding shims between the saw base and the HDPE pivoting blocks.
Clear?
Rick

bumpnstump
01-27-2013, 01:00 PM
Hint: Make the pivot point the cut-line and you get same cut-line with any bevel setting.

Dik, I must have been typing while you were posting- see my post right after yours.
r

Burt
01-27-2013, 01:35 PM
Rick,

Super job!


Burt

jswingchun
01-28-2013, 03:57 PM
That is awesome. Wish Dino sold something like that.

hint, hint hint....

;)

havehammerwilltravel
01-28-2013, 07:58 PM
Nuff said!:cool: