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Sean Leonard
04-20-2020, 1:35 PM
I’ve got this old SCM F4L 16” jointer and looking to set the knives on the cutter head. My only experience with a jointer or planer cuttterhead is the hobbyist type Dewalt 13” planers.

The gib screws can back out all the way and I can slide the gib a little, but can’t figure out how the knives are released. No manual for this old machine.

The s63 planer has the same style.

I attached some pics to help illustrate. Anyone have some wisdom they can share?

Sean Leonard
04-20-2020, 1:44 PM
Here's the image of the jointer cutterhead

430849

Sean Leonard
04-20-2020, 1:55 PM
430850

another angle of it

Brian Hale
04-20-2020, 2:21 PM
It appears that When you turn the gib locking bolts into the gib you should be able to remove it and the knife. There could be some gunk/rust holding them in so some gentle prying may be required

Charles Grauer
04-20-2020, 2:24 PM
It appears like there is a star shaped course adj ti the right of the gib that you will need to loosen then the knife should come loose. No positive but that’s what it looks like to me from your picture.

Matt Day
04-20-2020, 2:49 PM
You should just have to loosen all the gib screws (turn them so the head goes toward the knife). Once that’s done it all should lift out.

Sean Leonard
04-20-2020, 5:11 PM
Thanks. I saw those, and wasn't sure if they were meant to be adjusted. I only had standard box wrenches with me, but there must be a tool specific to adjusting those nuts. No standard wrench will fit in that gap to turn them. I'll go back with something like the wrenches for removing the arbor nut on the table saw to see if that'll work.

Bob Riefer
04-20-2020, 5:35 PM
I found that bike wrenches come in thin enough dimensions. Or grind down an unwanted wrench

Bill Dufour
04-20-2020, 5:37 PM
A service wrench should fit or just grind a regular open end wrench down until it is thin enough to get in there. I may be a good idea to remove the locking bolts and polish the heads nice and smooth were they contact the gib strip. If nothing else clean the heads well so no junk is making them sticky.
Some heads have springs under the knives to pop them up others you have to pry them up with a allen wrench or similar from the bottom. I made one by forging a thin screwdriver with a propane torch. Of course they will work better after all the gunk is removed.
You should have measured the knife extension before you started.
Meassdsu
Bill D

Ron Selzer
04-20-2020, 7:43 PM
I have good luck with tappet wrenches. However as was said grind a wrench down until it is thin enough to do the job. Once you have the bolt heads tight to the gib block, tap the block a little lower. The slot is tapered tighter at the outside verus the inside.
Good luck
Ron

Joe Calhoon
04-21-2020, 10:21 AM
I had that same head in a SCM jointer. Just loosen the bolts, mine had a thin metric wrench. 17 or 19mm I think. There should be springs under the knives. I had the cast iron setting gauge with mine but it did not work that great. When resetting the knives a little oil between the gib and knife helps to keep the knife from moving when you tighten the gib.

Jason Meinholz
04-21-2020, 3:49 PM
Here is the Operator Manual for the S630. Page 9.6 explains how to replace the knives.... 430947430946

Sean Leonard
04-27-2020, 12:41 AM
Jason, thanks. Is it your own copy of the manual, or did you find it somewhere for download? I'd be willing to pay you for a copy of that!

I picked up some thin head wrenches, but still needed to grind them down to fit but it did the trick. Surprisingly, nothing was seized up in the cutter heads even after over 30 years of these sitting idle. Love how simple the old SCM machines are.