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Ok, so I after seeing the all Aspen (sides/back) of Parker Archtop, I ended up using Aspen for my sides to match the top. Back and neck are old mahogany. The box is closed and and the dove-tail mortise cut and basically fitted to the dove-tail neck (but not glued).

Earlier while trying to trim the top and back with a flush trim router bit, the first moment the bearing touched the sides while the router was spinning, it left an indent in the sides. I only went about 1" and stopped to ensure the cut was clean. I notice this sort of gouge. Not quite a "line" or burn like I would have thought I would have seen but more like it was cutting the wood. I ended up trimming the sides by hand with a small plane, a rasp/file and block sanding. It took forever but it looks great! I did manage to get the router marks out and now the sides are flat and at a 90 to the top.

Now I am very concerned that if I try to add binding, that the bearing could make this same groove around the entire guitar. At this point I am not sure I could get a long continual groove out the entire top/back areas of the sides.

* one thing to note, I had made a ring that fit to the bottom of the trim router to hold itself up off the archtop to compensate for the recurve. The bit/bearing was not totallly flush to the side. It was a little more than flush to the side. So the bearing hit a very slight angle to the side (maybe 1 or 2 degrees). The top/back would have had to be finished cleaned with a block sanding, but that seemed ok.

I was thinking of building a binding router jig with the stationary arm supporting the router. This is the one where you spin the body of the guitar. With this style or any style for that matter....will the same thing happen with the router bearing? Is some wood more subseptable to this? I would think maple or rosewood probably would burn before it would gouge...yes? Does this happend on cedar?

Is there any tips to reduce or eliminate this? I am on the fence on whether I should add body binding to my #1 build in the first place. There is no neck or headstock binding....so it would not be too out of place. Now that I see how quickly all this work could be ruined due to the softer wood, I am concerned. Carving tops and backs take quite a bit of time.

Thanks for any comments.

Joe

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Joe

Joe my friend the crease that you see is caused by the edge, not the flat, of the bearing contacting the side first and a bit more pressure from the user on the router than necessary.

What a good binding jig will do is hold the router straight up and down from the guitar side so the the bearing rides flat on the side eliminating or at least reducing any crease.

Something that helped me before I got a Williams jig was to use less pressure and place some masking tape around the bearing. Be advised though that the masking tape will very slightly change your depth of cut so adjust accordingly.

Be sure also to be sure that the bearing can spin freely in the bit and remove and clean if required.

Good luck.

Yes it was riding every so slightly on the edge and not completely flat to the bearing. It cut a deep but very narrow groove. I did check the bearing and it seemed to spin freely.

So if the bearing was flat to the side, would it have reduce or eliminate that? Does the temper of the wood make any difference? Also, your comment on the user....so I may have been pushing to aggresively on the router to get it flush to the side? Normally I use routers for counter tops with plywood or MDF bases. So I tend to be a little heavy handed. I will try to be a little more gentle next time. I was just wanting to ensure the bit stayed flush all the way around. It didn't take much for me to say "OH F$%^&*"

THanks,

Joe

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Joe

Joe yes softer woods will, if presented with a bearing that is not riding flat, crease easier. I experienced what you did too and found that I was pressing to hard mostly because I have a healthy fear of routers and I am inexperienced with them too.

The Williams jig solved my problem but the tape will help somewhat as will a lighter touch for now.

You can also make a simple donut out of MDF that is a wedge of sorts that you make after calculating the angle of the guitar dome and using the angle that permits the router to sit straight up and down. Make a mark on the thinner side of the donut and as you circle the guitar turn the router so that the mark is always pointing toward the center of the guitar. This is not unlike how draftspeople will twirl their pencils when drawing a line to help keep a sharp point.

Here is a pic of a donut that I made and it is attached with double sided tape and has two coats of shellac on it to stabilize the MDF. I made a second donut for the back that had a greater radius.