15" planer knife setting advice needed....

[Kansas City Fireslayer]

I purchased this older blue Jet 15" planer a couple years back.  I am new to this style of planer and I've never changed the blades on it.  I recently picked up a new set of HSS blades for it and while waiting their arrival I thought I'd do myself a favor and remove all the blades to clean the head and gibbs.  Well the blades have arrived but I think I may have created a more complicated task for resetting them being I removed all the blades without finding the height with a dial indicator or other knife setting jig prior to removal.

I watched the Grizzly video on the planer pal jig where they find the "factory" height setting on a set blade and then they change them one at a time.  They mention the need to readjust the pressure feed rollers if the same blade height isn't reset.  This is something I really want to avoid if all possible.  Can anybody shed some light on how I should proceed from here?  Surely I'm not the first one to do this.  Here's a few pics of the head and machine.

<img src="http://i3.photobucket.com/albums/y82/damonakers/tools/5ED78D62-3AC9-41F2-BA5B-55B33528A55C.jpg" border="0" alt=" photo 5ED78D62-3AC9-41F2-BA5B-55B33528A55C.jpg"/>

<img src="http://i3.photobucket.com/albums/y82/damonakers/tools/53FF512C-6936-4D96-A1B8-B227EBB28996.jpg" border="0" alt=" photo 53FF512C-6936-4D96-A1B8-B227EBB28996.jpg"/>

<img src="http://i3.photobucket.com/albums/y82/damonakers/tools/3141EF7E-F7A6-4879-926B-13E8784CC150.jpg" border="0" alt=" photo 3141EF7E-F7A6-4879-926B-13E8784CC150.jpg"/>

[JGrout]

Do you have a knife setting gauge that came with the planer?  If so that is the way to set them. 

If not someone may have a gauge you can borrow 

I do not have one any longer


The real issue however is that you removed all the blades at once. This can be an issue when you reinstall the knives as it is possible to distort the head . What you will have to do IMO is set each knife with the minimal amount of pressure required to hold the knife in place on each one then work your way around the head until all the gib screws are tight.  At this point you likely will have to go back and reset each knife to the proper height.......  IME this two step process is necessary but the first time you do not have to actually set the knives  accurately just close so they do not hit anything while rotating by hand

That is why removing one at a time is recommended....

As for setting drive rolls this is the second reason most do not remove all knives at once. the Reset process is not really all that hard on that machine. It is just a bit time consuming but once done correctly the process is not that hard if it is ever needed again. 

The block and feeler gauge process shown in most griz manuals works just fine....

Joe

[fredhargis]

You are with no doubt the only guy who has ever done this!

  Seriously, maybe someone with a Jet 15" can get that measurement for you, then you will need some kind of gauge to allow you to get the knives set. The stuff Joe mentioned was news to me, but I'll take him at his word for the process to follow...but you still need a gauge, even a shop made one. there's quite a few of these planers in service, someone should be able to help.

[Kansas City Fireslayer]

Thanks for the info guys.  Just when you think you're past rookie mistakes, you make another.  Unfortunately, I don't have the knife setting gauge that came with the planer.  I bought the planer untested from a former city government department for $200.  I do believe I've located a setting gauge that will work for this 15" planer online for $25 shipped.  It's for 2 7/8" heads.  I'm hoping this gauge will put the blades at the needed height and then I can dial them in with a feeler gauge rested on the cast iron bed like Bob V. shows in his FWW magazine video.  The gauge is the typical "claw foot" looking assembly with the long connecting rod.  It rests on the head with the notch for the spring loaded blade to push up into.  I'm hoping this will get me where I need to be.

[texaswally]

It's more important that all the blades are at exactly the same height than the exact height.

[fredhargis]

Can you measure the diameter of your head?

[JGrout]

It is 2 7/8" Fred that is pretty much the standard for this class planer there are some oddball ones but not a Jet /PM/Griz/ad nauseum 

I just measured the one out of my PM15 I replaced a few years ago 

I also measured the knife protrusion and it was 3/16" from the point of the knife to the back (opposite side of the gibs) Which is the only real reference point you will have. 

Get the setting gauge there or check like grizzly for a comparable one just to compare price.

[Stwood_]

Head of that machine looks almost identical to my 20" griz.
That planer jig you have located, from your description, is what came with my planer.
It sits down over the head, with the center resting on the blade. The blades have little ink pen type springs under them, holding them up. You just set the gauge on the head, blade in the center of it, and push down. Then lock your numerous bolts.

---

http://shop.woodworkingmachineryservices...5gauge.htm

Yep, what my griz has

[MichaelMouse]

LOTS of setting gauges with a simple search.  I doubt there's much difference between exposure setting of my Rockwell/Invicta at 3/16 and any of the MANY clones motor up or down.  

http://shop.woodworkingmachineryservices...5gauge.htm

The advice to put in one knife at a time and half tension the gibs is spot on.

Dollars to donuts you'll have to remind yourself a half-dozen times that tightening is really loosening!

[Kansas City Fireslayer]

Well thank you everyone for taking the time to reply. I will order the arch style with rod gauge and shoot for the 3/16" initial setting. Then dial them in with a feeler gauge. I'll report back. The forum could use the activity!