climb cuts on a shaper

[Erik Christensen]

I have a 5 HP shaper with 4 wheel feeder and the last few times I used it I have tried climb cutting as I was getting way too much chip-out on hard maple when using a normal feed direction. It worked great but left me wondering - when is it NOT a good idea?

I did notice that there was a bit more sawdust with a climb cut; but my shaper has dual 4" ports and it is connected to a 6" clearvue system so even running it for a hour or more I had maybe 2-4 cups of extra sawdust on the floor. Finish was much better - zero chip-out and on hard maple there were no "climb cut fuzzies" that I could see.

So all you veteran shaper users - how do you determine feed direction?

[J.R. Rutter]

I climb cut when the edge absolutely cannot have any tearout - like for door edges - or when this shaping is just about the last step on a part with significant investment of time. As a side note on dust collection, I made an supplemental capture hood that slips over the outfeed fence and captures most of the stuff that gets thrown past the shaper hood.

For raised panels, where the edge is hidden in the groove, I just use a normal cut.

I also try to avoid end grain climb cuts when possible, because the cut quality is not as good, IME.

I used to climb cut sticking for doors, but by removing 1/32" to 1/16" extra along with the profile, tearout is essentially eliminated.

[Peter Quinn]

I climb cut only when I really have to. Some species sort of require it. I've had some soft and hard maple that would not work otherwise for door sticking, slots with typical 3Z groover without spurs, the occasional cranky batch of walnut and such. I' don't think its the most positive thing for your cutter sets over the long haul, something about extra heat being generated? Not sure there, but I have experienced a bit of the fuzzies on some things when climbing, others not, and the dust collection is never quite perfect. Its really bad with slot cutters as it shoots the dust forward up the channel that has just been created.

I usually mill extra pieces of most things I'll be shaping in a batch, so if its not going well from the start I may switch to climbing right away if the wood I'm working seems to need it, otherwise I run standard counter cutting direction.

Its not a good idea to climb small parts that will have less than 3 wheels in contact at all times. I shot some right out of the machine doing that! Luckily it fires them AWAY from you when climbing, and nobody was in the line of fire. So small parts are definitely out unless you enjoy using your shaper as a skeet launcher.

[Rod Sheridan]

Same thoughts as the previous 2 posts.

I do it when required, the dust collection is poor unless you make something to capture it on the outfeed side.

Sometimes it's the only way to prevent chipping however.

Regards, Rod.

[David Nelson1]

I have a 5 HP shaper with 4 wheel feeder and the last few times I used it I have tried climb cutting as I was getting way too much chip-out on hard maple when using a normal feed direction. It worked great but left me wondering - when is it NOT a good idea?

I did notice that there was a bit more sawdust with a climb cut; but my shaper has dual 4" ports and it is connected to a 6" clearvue system so even running it for a hour or more I had maybe 2-4 cups of extra sawdust on the floor. Finish was much better - zero chip-out and on hard maple there were no "climb cut fuzzies" that I could see.

So all you veteran shaper users - how do you determine feed direction?

Erik,
Not to high jack your thread, but what is a climb cut?

[Karl Brogger]

Some power feeders the gears can be swapped around to get a super slow setting out of it.

With a insert head for panel raising, and the power-feed in "super turtle" I get an almost glassy cut out of my panel raiser. Maybe one out of 50 door panels I'll get sufficient tear out that I have to rip some off and glue on a chunk.

[Paul Murphy]

Erik,
Not to high jack your thread, but what is a climb cut?

Climb cut is where the cutter rotation will try to pull the uncut stock into the cutter. The safety concerns are the cutter can take a ever increasing chip size until the cutter digs in and launches the stock at cutter tip velocity.

Most people wisely use a power feeder when climb cutting on a shaper. If the operator is hand feeding stock during climb cutting, the operators hand may be QUICKLY pulled into harms way if the operator fails to control the stock.

The advantage of a climb cut is the final angle of cut is more in-line with the surface being created, reducing the forces that result in tearout.

[Brian Kincaid]

Erik,
Not to high jack your thread, but what is a climb cut?

A climb cut is when you are feeding material into a cutter spinning away from you instead of a normal cut where you feed into a cutter spinning toward you.

If done by hand a climb cut will take your workpiece and launch it as the cutter would want to grab the workpiece and have material to bite into as it spins/launches. Climb cutting with a hefty powerfeeder is an accepted practice.

Also, scoring blades on table saws are reversed from the main blade and they utilize a climb cut but it is very shallow maybe 1/32".

-Brian

[Steve Griffin]

I almost always climb cut edge profiles, but never panel raising or any other crossgrain operation.

Even grooves get put in climb cutting--even though dust collection is not as good, I like virtually never having a chip out.

In fact, almost every board in my shop gets climb cut straightcutter to clean up the edge.

Thousands of miles of climb cutting, I have yet to see the dreaded skeet launched piece of wood. But I'm adamant about not having anyone ever in it's shooting path.

BTW, it can be a safe and good idea to climb cut with a router. I do it all the time in certain woods with 1/8 and 1/4" round over bits and light passes with flush trimmers if it improves the cut quality. Nothing bigger than that, and one should be extra careful.

-Steve

[David Nelson1]

Thanks for the info Paul and Brian. I needed to know so I dont do anything stupid, Lord knows I need all the help I can get. LOL

[Ben Abate]

Some power feeders the gears can be swapped around to get a super slow setting out of it.

With a insert head for panel raising, and the power-feed in "super turtle" I get an almost glassy cut out of my panel raiser. Maybe one out of 50 door panels I'll get sufficient tear out that I have to rip some off and glue on a chunk.



Karl,
So you do use insert cutter heads also to climb cut....I"ve never tried it because I was worried about breaking off a carbide tip....Lord knows I got an education one day not paying attention when swapping out cutter heads and put an insert cutter on upside down....That was a real shame, lost all my carbide inserts........expensive!!!!!!!!! You only do that once. And hopefully not at all.....But getting back to the question, you have no problem climb cutting with the inserts? That's nice to learn....

Ben