Rim overhang

[sprucetop1]

What's the best way to cut back the excess wood overhanging the ribs after the top and back have been glued on? I've been doing it with a small flat-soled violin makers plane and sanding sticks.....but I'm not very good at it, it's tedious and it's very easy to damage the ribs. The neck area is particularly difficult I find. Advice gratefully received.....John

[Jim Hilburn]

I just did some of that yesterday. I have a small Kunz flat bottom plane, a coarse and a fine rasp and a straight scraper that all got used. Now when I do a mandolin I can use spool clamps to evenly support the body and use my occillating drum sander but this is an octave that was just too big for the sander's table.
But for future reference, I think it's a good idea to try to keep the plates as close to actual size as possible. Use your mold which should be exactly the right size and be very careful with the centerline. Otherwise how do you make a consistent recurve? You need to know where the boundaries are.
On an F the only place you positively have to be sure you have enough wood to go over the edge is the upper part of the scroll. Everywhere else is getting cut for binding anyway.

[sprucetop1]

Jim...thanks for advice. I definitely left too much overhang on the back and will have to be more accurate next time round. It doesn't help that this back is particularly hard with difficult grain.......

[Jerry Haynes]

As the others stated...you should get it as close as possible to begin with, just makes for less removal. This may not be the best way , but it works for me.. Moto tool with flex shaft, sanding drum with 80 grit. Go slow all the way around and be careful at the points, it's real easy to jerk the point off. Take it down almost flush with the sides, then I use an orbital sander to smooth it all up. Orbital sander will remove any leftover glue. Then you're ready to cut the binding channel. Hope this helps. Jerry

[Lefty Luthier]

If you have a drill press, use a 2 inch diameter drum sander with 80 grit paper to get close and then switch to 220 grit for the final passes. Been doing it this way for years with good results. Any use of a blade against the cross grain at the tail is likely to cause small chunks to pop off.

[Michael Lewis]

Patience.

With the design of the finished instrument in your head, you proceed through each step until the design is complete.

Patience.

You gain skill to prevent causing any damage, and to hasten the process.

Patience.

Focus on the completion of each step.

Patience.

The better you get at each step the quicker you will proceed. the more you do the better you get.

Patience.

Here, have a cup and relax.~o)

[sprucetop1]

Any use of a blade against the cross grain at the tail is likely to cause small chunks to pop off.

.....my experience exactly !

No doubt that PATIENCE will pay off. I'm almost there with 90% of the rim area........just leaves the neck/body section.....on that 1st. thing tomorrow....

thanks to all....

[Magnus Geijer]

Patience... I've heard that word. It's a small tropical fish, no?

I use a dremel until close, and then hand sand.

/Magnus

[Yonkle]

I have just sat the body on my bandsaw and took it off. You have to be careful doing it this way not to hit the sides, but it works fast and clean. If you are binding the body your router will take it off anyway, but I still like to start with a fairly flush edge regardless. Jd

[Rick Turner]

Have you seen the "RoboSander"? It's a sanding drum with a large bearing on the bottom, so it works like a pattern router bit. Make a cradle to hold the mando and put the RoboSander in your drill press and just sand around. It won't get into corners or scrolls, but it would do the rest.

I'd be tempted to do this on my pin router with a ball bearing guided bit.

I do the instruction pancake mandos on a table router with a ball bearing tipped bit. Climb cut where you need to, conventional cut where you can.