Rounded edge - but not in rabbet

[John Pariseau]

I have a board that will fit into a rabbet cut in a piece of wood - see attached image. I don't want to round the edge of the wood that rests in the 1/4" deep rabbet, obviously. My question is a simple one:

What's the best technique to figure out where to stop the 1/4" round? Do I dry fit, mark, then cut up to it? Is there a hand scraper that I can use after the wood is glued/screwed?

482310

[Brian Tymchak]

I think I would assemble with square edges then use a chisel, scraper, and sandpaper to shape the edge. You might be able to get a homemade scratch stock in there but it looks like tight quarters.

[John Pariseau]

I think I would assemble with square edges then use a chisel, scraper, and sandpaper to shape the edge. You might be able to get a homemade scratch stock in there but it looks like tight quarters.
That was my conundrum - with the angle (120) and amount sticking out (1" on either side) trying to scrape it seems problematic. I can try the chisel method, but I fear I won't be able to be as consistent as I'd like. I suppose I could route 1/2" and use that to guide my chiseling.

[Jim Becker]

Make a custom scraper with a piece of steel and some files that you can get in close to scrape the roundover followed by refining that last little bit you can't get to with the scraper because of the angle with blades and/or sanding/files. Be sure to get a good pencil line during your dry fit so you have your exact stopping points top and bottom

[John Pariseau]

This all sounds good... it will likely be a week or two before I can put the advice into practice!

[John Pariseau]

I settled on dry fit+mark+router. After marking a few boards, settled on a set of offset measurements - marked the boards - and used my router + 1/4" roundover bit to mill up to the marked line. Worked perfectly, and I didn't have to do any hand scraping.

[Osvaldo Cristo]

I would dry mount the part into the rabbet, draw a pencil line in the limit, take off the shelf and carefully manually router it using the pencil line as guide to limit it. I would mount the parts again and would finish the edge with a chisel or cut knife.

Regards,

[Tom Bender]

Files and rasps can do this after final assembly. Protect the adjacent areas with tape.