Jointer technique question - chipout

[Grant Stevens]

Question for the masses....

First, the background. After following all of the threads recently about cutterheads for jointers and planers, I decided to stick with the stock cutterhead for awhile until I decide what to do. With regard to the equipment that I am using, I recently picked up a used 8" Jet jointer and 15" Jet planer (had a 6" jointer and [still have] a DW735).

Ok, now for the question... I seem to get a lot of chipout in cherry that I run through the jointer. In order to verify that I found the prevailing grain direction correctly, I flipped a couple of boards around, and it was much worse. So back to the original feed direction and I get some chipout. But when I run the same boards through the planer, I don't seem to get much of any chipout. So is it poor technique on the jointer that is causing this (e.g., feed speed, etc)? I would have guessed that if there were grain patterns running in multiple directions that I would see it on the planer too.

Any advice?

Thanks,
Grant Stevens

[Cliff Rohrabacher]

prolly dull blades. Could also be the grind on the blades.
Some carbide blades don't cut so well in hardwood.
Is the wood narrow enough that you can run it on a bias across the jointer??

[Jim Becker]

Excessive chip out on the jointer generally points at dull knives and/or material with grain/defects condusive to the same. Try dampening the surface of the wood slightly and running it through at a slight angle, but do check your knives. You mentioned it was a used machine...if the same knives are on it, they perhaps are, um...not what they originally were, as it were... ;)

[Grant Stevens]

Thanks for the quick feedback. I'll check the blades - looks like I may have a reason to pull the trigger on the Esta Dispoz-a-Blade set now...

Thanks,
Grant

[Ted Miller]

Grant, If edge jointing you can turn the board around and run the end of the board about 2-3" in then spin the board the correct way and run it through and see if this helps your problem. Are you taking a large cut?...

[Grant Stevens]

Ted,

Thanks for the reply. I am taking a thin cut (1/16 or so). I am seeing a lot of chipout all along the board when jointing the face...if I was just seeing it just at the end, I think your suggestion would be a good one. I will try to keep it in the memory banks for the future.

I suspect the other folks are right with regard to dull blades - I have to go back out and take a look.

Thanks for the feedback from all,
Grant

[Pete Brown]

Ok, now for the question... I seem to get a lot of chipout in cherry that I run through the jointer. In order to verify that I found the prevailing grain direction correctly, I flipped a couple of boards around, and it was much worse. So back to the original feed direction and I get some chipout. But when I run the same boards through the planer, I don't seem to get much of any chipout. So is it poor technique on the jointer that is causing this (e.g., feed speed, etc)? I would have guessed that if there were grain patterns running in multiple directions that I would see it on the planer too.

I had really bad chipout on my jointer. Turns out it was because my knives were not properly aligned. Do you also get a lot of scallop (most easily seen when you joint an edge)?

Pete

[Richard Butler]

Get some new blades and install them using the Bob Vaughn method.

http://video.google.com/videoplay?docid=2983839096587014177

[Seth Poorman]

Try turning your depth of cut down to 1/32",I keep my jointer set at this setting all the time...I would think w/ sharp blades and shallow cut you should come out good!! :)