strategy for mortise and tenon marking when drilling out waste

[Marko Milisavljevic]

I find it tricky to reliably drill out mortise waste close to line yet without going over. I'm considering whether a smart strategy would be to lightly mark mortise (maybe just centerline, with knife), drill out the waste as well as I can, then mark mortise again with knife just outside of hole edges, then set mortise gauge to fit, by letting pins or wheels fall into knife lines, and transfer this onto tenon stock (or maybe just adjust mortise gauge by eyeball and slide-along trial). I assume this is universal, but I'm just discovering that tenon cutting is far more accurate and controllable than mortising, at least by hand, and this seems the best way to deal with that.

[Noah Wagener]

I think using a smaller diameter bit than your marked out mortise would amount to the same procedure you are describing. I think the type of bit you use might help as well. Like a lead screw auger. Using a brace to get the hole started might be more accurate than a drill, especially if it isn't variable speed. You may want to make a mortise in a scrap to use as a jig.I think people who drill mortises make the hole smaller and pare to the line. Maybe chopping with a chisel might suit you more than drilling.

[Sam Stephens]

i find it faster to chop a mortise than drill it out and pare.

[Don Jarvie]

Mark the mortise out with the knife and drill out the mortise leaving a bit of wood before the line then use a chisel to clean up the rest.

[Derek Cohen]

Whether you chop or drill/pare, first chisel away the top layer. That way you are working below the surface and will stay within the lines ...

http://www.inthewoodshop.com/Furniture/MorticingByChisel_html_7fa3da55.jpg

http://www.inthewoodshop.com/Furniture/MorticingByChisel_html_m2306234.jpg

http://www.inthewoodshop.com/Furniture/TheChairMortices_html_2a41450e.jpg

http://www.inthewoodshop.com/Furniture/TheChairMortices_html_32804443.jpg

http://www.inthewoodshop.com/Furniture/TheChairMortices_html_a50522c.jpg

Regards from Perth

Derek