I am building a table top out of 4 edge glued boards. 2 of the
corners have a radius to them. I have a piece of MDF that I am using
as a template, with a trim bit and about 1/8 to 1/4 overhang rough cut
with a jigsaw. I am moving around the edge counter-clockwise. As I
cam up the left end and round the turn around the first radius,
suddenly the router "caught" and a hunk of the edge tore loose. I
moved past it and completed the rest of the cut around the edge
without incident. I glued the broken piece in and it isn't noticible,
but now I have to match the edge and I'm leary of using the rounter on
My theory is that that point of the cut was just too thick and I was
taking too much off at one time, and perhaps the grain was funny
there. The way I want to proceed once the glue has been on for 24
hours is to sand the offending piece down to about 1/16" from the
template and then route that off.
As you rounded the radius the direction of the grain in the wood changed and
instead of cutting across it you found yourself cutting against it. I like
working ash and mahogany. Mahogany is fairly well behaved but the ash as a
tendency to tear along the grain line when cutting against the grain.
There are two ways to avoid the tear out. 1) Don't rout against the grain,
always rout with it.
The second is useful when you have to cut against the grain. The simple
cure is do a "climb cut" where you rout in the direction your router is
turning. The one thing to watch is that it does not take off on you,
meaning you have to hold it tight to the piece and be ready for it to start
to run away with you. As long as you are careful, it works like a champ.
I agree with Deb.
Climb cutting, when done with caution and common sense (router hand
held ... NEVER in a router table) taking small cuts and nibbling away
slowly, is the best way to handle tough grain.
Radius only the right hand upper corner. (Facing a piece of paper, the
upper right hand corner where the date often goes). Turn the work over
as you go so you're only routing that corner.
The answers about routing end grain or against the grain is like the
others said, climb cutting, especially at corners.
However, now that you have this situation with a glued in patch, you
might consider using some hand tools such as a coping saw, super sharp
pairing chisel, rasp, file, custom shaped scraper, etc. Or even
multiple nibble passes with the table saw at various tilts to trim
close to the radius. Then make a reverse shape sanding block and sand
it out to a good finish.
Spirals do a little better but once a spiral grabs it really grabs.
Unlike a wing cutter that is going bang, bang,bang, if the spiral
grabs the wood it seems to just pull quite a bit more. My most
dangerous router stories involve spirals. I now pretty much only use
them in a table, but this is just my bias, having broken one while
freehanding and luckily having it not embedded in my gut, as it was in
But isn't Pat Warner's
suggestion really the best one? Just turn it over first and do the
I know *I'd* never question Pat's wisdom re: routers, router safety,
my $1/50, ymmv, etc etc and so on and so forth....
If the shape of the workpiece allows it, then yes, turning it over is
the easiest way to continue routing "with" the grain, but it's not
always possible. Otherwise, some form of climb cutting is the only
alternative (other than foregoing the router for other methods, as
What I usually do (after removing as much waste as possible using other
methods, such as the bandsaw) is to reposition the piece on the downside
of the waste area, as though I'm going to make a full climb cut, but
I'll take a bunch of little router-bit-sized "bites" out of the tail-end
of the waste area, keeping the workpiece moving in a circular motion
against the grain and into the bit (so it's not *really* a climb cut),
using push blocks to maintain firm downward pressure and with very firm
and deliberate strokes to prevent the bit from grabbing the workpiece.
Free bad advice available here.
To reply, eat the taco.
Well, I got to it last night and all went well. I ended up using the
router and took very small bites out of it until it got almost to the
template, then finished it off. A little sandpaper and then a
rounding bit, and you can't see anything. Thank's for all the
advice. Now for finishing...
Thanks for all the help. If anybody is interested, this is how it all
Looks nice. I like the thin stripes of darker wood in the midth of the top.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.