Is a Power Planer really a power Scraper ?

[C. in Indy]

Philosophers:

Sorry if this has been treated before, but I keep thinking the rotary blades on power planers and jointers are really hitting the work at angles more like scraping than planing.

I hardly ever use my power Jointer, but I recalled the blade bevel honing was supposed to be in the 37.5-45 degree range, and it hits the work "bevel down" at what would seem to me to be about 90 degrees "bedding angle".   So I think it's a scraper.

Typical power planed boards, I would say, avoid tearout to an impressive degree, but they don't have the "sheen" that you get with low angle planing.

Your thoughts ?


Chris

[Bill_Houghton]

Seems like more of a question for the general board than here where our tools burn cholesterol instead of electrons.

[MichaelMouse]

Philosophers:

Sorry if this has been treated before, but I keep thinking the rotary blades on power planers and jointers are really hitting the work at angles more like scraping than planing.

I hardly ever use my power Jointer, but I recalled the blade bevel honing was supposed to be in the 37.5-45 degree range, and it hits the work "bevel down" at what would seem to me to be about 90 degrees "bedding angle".   So I think it's a scraper.

Typical power planed boards, I would say, avoid tearout to an impressive degree, but they don't have the "sheen" that you get with low angle planing.

Your thoughts ?

See Hoadley.  However, you ARE feeding into the rotating blades, so "bedding angle" needs to take that into account.  I see the action as similar to almost all carving movements - enter steep to cut and lower to run.

[Bruce Haugen]

You still need to pay attention to grain direction.  I have a good planer, but it will definitely produce tear out against the grain.

[tomsteve]

You still need to pay attention to grain direction.  I have a good planer, but it will definitely produce tear out against the grain.

and even with paying attention to grain direction there can be tearout- especially on figured wood.

[HomerLee]

and even with paying attention to grain direction there can be tearout- especially on figured wood.

I have a nice Grizzly parallelogram jointer that I hardly use anymore. Too often I hear that popping sound that means tear out. Do most of my jointing with hand planes after I get it close with a Freud Glue line blade on the table saw.

Sorry, but there's no "blended tool work" section on this forum. 

[Skip J.]

I have a nice Grizzly parallelogram jointer that I hardly use anymore. Too often I hear that popping sound that means tear out. Do most of my jointing with hand planes after I get it close with a Freud Glue line blade on the table saw.

Sorry, but there's no "blended tool work" section on this forum. 

I think almost all of us are "blended tool" workers....

[Phil Thien]

Wouldn’t a better indication be the chips produced by the device?

I’d think scraping would product finer shavings than I get with my powered jointer and planet.

[Scoony]

I would say that it is a cutting action, not a scraping action.

The rotating blades create short shavings and will never produce the sheen that a hand plane can, but then I never heard anyone claim a finish ready surface from a tailed planer/jointer.

[Axehandle]

Its definitely more of a cutting action with a helical cutterhead.  The inserts are bedded at an angle even.