Spliced Riser Wood Adhesion Question

[Erwincm]

Hi guys. I'm about to attempt my first multi-wood riser. I'm not even sure what you call it but it's the designs that have a curved phenolic strip running between two different wood pieces - one convex cut and one concave cut - to form a composite riser structure. I plan to use my snazzy new Robo-sander and custom template to do the job. I did a practice run and the sanded surface of the practice wood ended up smoother than I expected. I'm using the roughest Robo-sander grit I could find (60 grit I think). Should I rough up the wood bonding surfaces a bit more before epoxy application? If yes, any suggestion for a suitable tool to do this? Do they make a grooving file of some type?? Am I worrying too much???

Thanks,
Charles
Madison, AL

[BigJim]

Probably worrying too much. 60 grit is just fine as long as you didn't burn the wood. It doesn't necessarily look as rough as it sounds...60 grit that is.

good luck, bigjim

[Pheonixarcher]

I use the luthier's friend to shape my riser pieces for glue up. I believe it's the robo sander, only with a table attachment for the drill press. It works great with 60 grit! Make sure your drum is perfectly square to the table, and you'll have no problems if you use a good epoxy such as smooth on. I use c-clamps to clamp in place while the epoxy cures, and I haven't had a starved glue line yet (knock on wood).

[beachbowhunter]

Your set up sounds exactly like mine. No problems at all. Only make sure that the phenolic is rough sanded real well. That is the slickest part of the set up. I did a thread on how I do it.  Brush Wolf also posted a great thread that got me motivated.

 http://tradgang.com/noncgi/ultimatebb.php?ubb=get_topic;f=125;t=012495;p=1

[Robertfishes]

Also make sure your pieces fit without forcing them together.

[Erwincm]

Ok, I'm glad I asked. I feel a lot better now :-) I plan to use smooth-on and C-clamps to hold the pieces together while they set up. I'll actually be using a couple of pieces of Core-Tuff for the riser accent strips so I assume they should glue nicely without any additional snading/grinding since they are a fiberglass product similar to limb glass. Thanks again for your help guys! I'll post pics if/when I finish this one...

[Pheonixarcher]

The core tuff doesn't really need any additional sanding. Phenolic will need some roughing up. Just make sure all your pieces are clean and free of dust, and be sure to rub the epoxy into the grain and pores of both sides of the gluing surfaces.

[Erwincm]

Good call Phoenixarcher. I never thought of rubbing the epoxy into the wood pores but that does make good sense.

[Krasus]

Smooth on works best on sanded smooth surfaces. Go at least 180 grit on your wood components.