sandpaper for finishing joint?

[Alexis]

Hello,

am I the only one who uses sandpaper for the finish on my joint? I found that gluing a piece of sandpaper on a flat piece of wood does the work real good... like a poor man rabbet plane!

Alexis

[shinnlinger]

I prefer a SHARP chisel, but have resorted to a belt sander when I had highschool kids cutting joints....

[beenthere]

And you use sandpaper for what specific reason?

Not sure just what joint you are referring to here.

A pic maybe? 

[Alexis]

I was speaking of a tenon or the inside of a mortise...

what I mean is that after paring against the grain and being almost "to the line" The finish is a bit rough and has some bump. I like to finish it with my sandpaper on flat backing. It just makes the surface smooth and then I can use my framing square to make sure it's at 90 degree to my reference face.

I found that if I do the final paring with the grain, the chisel tend to dig too deep and, for example, the tenon would be too small close to the shoulder than at the end...

[beenthere]

Seems if the joint fits together, then any additional removal (sanding or otherwise) would only serve to loosen the joint. Or am I missing the point?

I'd only sand to make an exposed surface better for a better finishing job. Sanding for gluing seems would make a poorer gluing surface.

Now if the joint doesn't fit and needs wood removed, that is different story. 

[Dave Shepard]

I haven't tried that technique. I do most of my tenon work with a framing chisel. Today, I was working on some longer scarfs, so I used a slick to rough out, and a hand plane to finish. I say use whatever works for you, and gives you an acceptable dimension.

[moonhill]

Alex, I think you may need to use the sand paper on the chisel instead of the wood, I am serious.  Brad bb has a good method perhaps he will expound.  You need to reshape your chisel so it has a curve in the blade from edge to edge.  Remove a slight amount off each edge and test with a straight edge so you see light on the edges, the straight edge should be touching in the middle.  Also you can input a curved radius on the cutting edge of the chisel.  This will allow you to clean up the mortice and tenon without the edges cutting in and leaving ragged walls.  I use a slick to clean up everything, the chisel comes out to touch up the ends of the mortice or knots. 

After using sandpaper I would not want to put my cutting tools back on the same wood, the grit left behind will not be kind.

Tim

[Brad_bb]

Tim, I don't do as you describe. I do use the sandpaper sharpening method though.  Here's a pic of my setup.





3/8 thick plate glass about 3ft long, held in a frame made of MDF and pine rails and end clamps.  Pressure Sensitive Adhesive (PSA) sandpaper stuck on glass, 80, 150, and 220 grit.  After tuning on those as needed, and cleaning in between grits, wet/dry automotive sandpaper is laid over the 150 and 220 grit PSA.  Friction will hold them.  Wet/dry grits are 400, 600, 800, 1000, 1500.  I have a strop, but don't have compound yet to try it.

[Alexis]

Jim, I just reviewed you cutting a tenon on a timber post...

One small question, at what point do you pare against the grain? It seems you only pare with the grain,maybe that's why I have a hard time getting a flat surface. I can get clean shaving when I go with the grain, but not much when I am against...

Alexis

[Jaybolicious]

A large chisel and  Tormek sharpener makes life a lot easier. Shoulder and small planes help too. 

[Brad_bb]

Putting a radius on the bevel side of the chisel sure will help reduce time and effort when sharpening.  Unfortunately I don't have a machine to give me that radius.  I only have one bench grinder set up with a coarse stone for rough steel grinding, and a finer stone dedicated solely for grinding points on Tig welding Tungsten tips.  I guess I need another cheap grinder.  It's ok for me now sharpening via the sandpaper method without the radius in the bevel.  Having the radius just removes material from the bevel and thus the surface area you sand when sharpening is much less, so therefore is quicker and easier.  I know there's a special name for this....oh yeah, hollow grinding.