Original Incra jig with OPR

easterngray · Post by **easterngray** » Wed Nov 17, 2010 9:15 am

Has anyone set up their overarm pin router to work with the original Incra Jig? I would love to see your set up- thanks - Alec

8iowa · Post by **8iowa** » Wed Nov 17, 2010 9:45 am

I would like to see this too. I have an Incra jig and have never used it.

dasgud · Post by **dasgud** » Wed Nov 17, 2010 12:49 pm

Hi

I used the Incra jig with my router table and with the dado saw. I dont have an opr (yet) so have never used it in that operation, but I'm sure it would work just fine with the OPR. I've used the Incra jig to make finger joints, tongue n groove, and to attach a solid wood edge to cover up plywood edges.

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Here it is mounted on my router table.

I did have a small problem that I wanted to write on this forum about, but just never did because I finished that project and it was difficult to describe. I'll try again now. The Incra jig fence will extend out 8", but the work piece (my home made bench vise) I was working on was 12". What I decided to do was center the work piece for my first cut, move the fence 1" away for a 1/2" dado to make the 2nd cut. Then, I flipped the piece around 180° to cut the other side of the center. That was on the faces of the vise. When I finished that, everything looked great. I even test fit the two faces together to make sure the box joint pattern was even. It was and the joints were tight.
Then it was time to shape the edge pieces and this is where the problem happened. Everything fit right except the very center piece. I thought about what happened for two days and tried lots of things to fix it. One thing I thought to fix it was taking material away to make it fix (the center was too tight by about 1/32" or so). But if I did that, it would have created gaps. I finally decided that if I cut the center with a thin blade backsaw it would give me the fit I wanted.

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So cutting a thin kerf allowed me to move the edges in toward the center and let everything fit. If I tried to cut material off anywhere else I would have had gaps.
I never did figure out why they wouldn't fit, but what I did figure out is if I didn't flip end for end the spacing would have been right. That's why I made an 8" spacer to allow me 16" total. That should be plenty of room for what I need to make.

dusty · Post by **dusty** » Wed Nov 17, 2010 1:53 pm

I believe that your problem was introduced when you flipped the work piece end for end. I believe the root cause was that your center was really not "true center".

It sounds as though the only fit problem you had was with those three center elements. This tells me that your basis procedure and the Incra were all working fine.

I have the original Incra Jig like yours and another that they also call the Incra Jig but it is actually the original Incra Fence System. I love them both and believe that they do truly perform as advertised.

pennview · Post by **pennview** » Wed Nov 17, 2010 2:04 pm

I have both the overarm pin router and the incra jig, and I've heretofore thought they were incompatible because of the column being in the way of centering the jig on the table, although one could use two jigs, one on either side of the column.

But, looking at the OPR with jig in hand, I saw that one could mount the jig in the back, right corner of the table at an angle, so that the stock could be passed diagonally over the table. Also one could tilt or rotate the arm so tha the jig could be mounted off-center. Or, the column and arm could be removed.

I bought my table used and it is the one with the router plate for mounting a router under the table, as well as on the arm over the table. It has rows of threaded inserts screwed into the table top that are used to position the Shopsmith fence.

Well, the previous owner installed some extra inserts in the table, mostly in the back corners, and while sliding the incra jig around, I noticed that some of those extra inserts matched the spacing of the slots in the incra jig for mounting it to a router table. On my table, there are two extra inserts parallel to the back edge of the table on both the left and right sides of the table. And on the right side, toward the back of the table, there are two inserts set at an angle to the back of the table. So, it's quite possible that the previous owner of my table was well ahead of us on how to use the incra jig on the OPR.

dasgud · Post by **dasgud** » Wed Nov 17, 2010 2:51 pm

Dusty, I suspected that it wasn't true center but before I made my first cut I used a sacrificial piece that was the same size. I cut to the center and flipped it end for end and cut again to see if it was in fact centered. I didn't shave any more material from either side heavily. It was a good test. i didn't dry fit the sacrificial pieces (face and edge) together because I was only testing that I would be centered so I only made 3 cuts on the face and 2 on the edge piece. I didn't have a caliper then so I didn't have a precise measurement of the teeth, but every measurement I took and every angle I checked from the teeth looked good.

Another thing I did was dry fit the vise faces together after shaping and they fit fine. Also the edges fit each other with no play. Just when I tried to mate the edges to the faces is where the problem arose.
I really did ponder what the issue was for two days and just could not figure it out. So to this day it's still a mystery.

Ron309753 · Post by **Ron309753** » Wed Nov 17, 2010 3:10 pm

pennview wrote:Well, the previous owner installed some extra inserts in the table, mostly in the back corners, and while sliding the incra jig around, I noticed that some of those extra inserts matched the spacing of the slots in the incra jig for mounting it to a router table. On my table, there are two extra inserts parallel to the back edge of the table on both the left and right sides of the table. And on the right side, toward the back of the table, there are two inserts set at an angle to the back of the table. So, it's quite possible that the previous owner of my table was well ahead of us on how to use the incra jig on the OPR.

I have the free-standing OPR with the same table. I don't have the manual handy, but if I remeber correctly the table came with the Incra jig holes already there.
Is this same jig that was in Dasgud's picture?
http://incra.com/product_rtf_originaljig.htm

Sincerely,

Ron309753

dasgud · Post by **dasgud** » Wed Nov 17, 2010 3:26 pm

Ron309753 wrote:Is this same jig that was in Dasgud's picture?
http://incra.com/product_rtf_originaljig.htm

Sincerely,

Ron309753

That's the same jig Ron. Just a better picture and a cooler black than my boring grey

.

dusty · Post by **dusty** » Wed Nov 17, 2010 4:19 pm

I enjoy using the Incra Jig and the Incra Fence but when using it you need to have your wits about. I believe this is especially true when cutting from opposing edges with expectation of meeting in the middle. It's sorta like digging a tunnel from opposite sides of the mountain. A partial overlap is not a mark of success.

I did a lot of box joints and dove tails before I got a set that fit without using a hammer or knife at the end. Once you get the hang of it, it is sweet.

If something comes up to distract me, I just stop. Missing the notch by one introduces a 1/32" error that can multiple on itself as you go. I spent a lot of time scratching my head and asking "Now how did that happen"?

pennview · Post by **pennview** » Wed Nov 17, 2010 6:04 pm

Originally posted by Ron309753
I have the free-standing OPR with the same table. I don't have the manual handy, but if I remeber correctly the table came with the Incra jig holes already there.

Since I didn't buy it new, I can't say one way or the other. However, I have a second table that doesn't have those additional holes. Like other Shopsmith items, there probably are various iterations of the table.