Jointer knives question

[Eric John]

Hello all,

I am putting in some sharpened knives, really just licked them on 1200 1500 paper and honed them.
Delta DJ-20 HSS 13/16 knives.
while putting them in I notice the cutting edge is just, just above the gibs, maybe by a 1/64?
is that usual? they were like that before also, but I thought I would ask those in the know.
is that an acceptable amount? should they be higher above the gib?
before I proceed setting them, felt like I should ask.

Thanx
Eric

[Rod Sheridan]

Hi Eric, the important dimension is height referenced from the outfeed table.

Unless the knife has too much projection, whatever you wind up with above gibs isn't very important. (As long as they're above obviously).

[Andrew Hughes]

Your knife projection should look something like this.

[Peter Christensen]

Eric on Page 23 of the manual says 0.015" bigger than the cutter block diameter.
https://www.utpb.edu/docs/default-so...4.pdf?sfvrsn=4

There are a variety of jigs on the market that make the job easier.
https://www.ebay.ca/itm/Adjustable-M....c100677.m4598

[Eric John]

OK, so apparently as long as cutter is above gib to some extent it will be a non-issue (so, sez Delta)
but just for your amusement.....
I set the knives using jointer pals, then my OCD kicked in.
checked them with dial indicator, they were within 2 thousandths front to back, re adjusted a bit,
and finally went back to my grandfathers method with a square stick and two marks 1/8" apart.
yup that did it now they're nutz, 2 hours later.
just tells me that sometimes grandpa new best.

Regards Eric

[Lee Schierer]

finally went back to my grandfathers method with a square stick and two marks 1/8" apart.
yup that did it now they're nutz, 2 hours later.
just tells me that sometimes grandpa new best.

Regards Eric

So tell us about Grandpa's method...

[Eric John]

Hello Lee,

Well basically, its the same one you see on you tube, but ill try to explain it here.
taka a squared piece of any wood about 1- 1 1/2 wide x 1/2 thick, almost any short length
but lets say 12".
measuring from the right two or three inches in, make two tick marks 1/8" apart.
set it at the back of the bed so that th right hand tick is at the leading edge of the outfeed table.
rotate the cutterhead till the top dead center of the wood"catches" and pulls it forwardto the second tick mark.
if it goes past the mark the blade is too high, if the blade is too low it will not pull the wood forward enough.
when you adjust the blade to where it moves the wood 1/8, then do the same at the front of the bed.
it will take some fiddling and going back and forth, but it does work.
then go on to to do the same with the other two blades.
that's it, low tech but it works.

hope that helps
Eric