Jointer/Technique Questions

[Mike Scoggins]

I'm in the process of making a box (as a gift) for my parent's 50th wedding anniversary later this year. The lid is being made out of a maple frame with a cherry panel. I cut two pieces of cherry to glue up for the panel and then discovered that the to-be glued edge was not square to the face. These boards are about 13" long; the panel length will be ~12-1/2". So, I squared up the fence on my jointer (which is where the problem originated to begin with; fence wasn't square) and ran the edge of the pieces through the jointer. The edges are now square to the face, but after multiple attempts, I've yet to get a perfect fit for glue-up. The ends have a small gap.

So, what's the problem here? Should I be able to run a 13" board through the jointer and get a perfectly straight edge (or is this just not enough length)? (NOTE: I've been very careful to ensure that I am not pushing down on either of the ends of the board as they pass over the cutter. Pressure is being applied on the infeed table first and then the outfeed table as more of the board moves past the cutter.)

Is my jointer somehow out of adjustment? My jointer is relatively new and this cherry is part of the first batch of rough-cut lumber I've run through it and the planer.

Any help is appreciated.

Mike

[Jim Becker]

The edges are now square to the face, but after multiple attempts, I've yet to get a perfect fit for glue-up. The ends have a small gap.

I'm reading that as you're noticing a small gap in the glue-up, but only at the ends of the boards. That generally means you are getting some snipe at the ends of the boards when you are using the jointer to straighten them and it's usually caused by either your knives not being aligned with the outfeed table or your infeed and outfeed tables not being co-planer. (Parallel in all dimensions)

One other note for jointing edges destined for panel glue-up...since it's nearly impossible to get the jointer fence "exactly" perpendicular to the bed of the tool, you really need to alternate faces when you do your edges. This cancels out any slight differences from 90º that may appear in the joint since on one board it's "down" and on the other it's "up". The best way to accomplish this is to draw a triangle with chalk or a soft pencil on the boards ordered the way you want to glue them up and be sure that your first pass is with the marking facing you and your second pass on the next and mating edge is with the marking facing away from you. Repeat until you get to the bitter end of the boards for that glue-up.

[Dennis Peacock]

I would check my outfeed table first since that would be the easiest remedy to begin with. It that doesn't resolve it....then it's time to check the knives and THEN check the alignment of both the infeed and outfeed tables. Let's just start out easy and then get more time consuming if necessary.! :)

[Mike Scoggins]

Jim/Dennis,

Thanks for your help/suggestions.

Dennis,

I checked the outfeed table, and it was just a hair low. Raised it even with the cutters at top dead center (which I thought I had done, but obviously moved it somewhere along the way), ran the edges of each piece across the jointer one time and perfect glue line. The glued-up panel is ready for machining. You were right on, and the fix was easy!

BTW, this was the first time I've used rough lumber in my work (which is probably evident by my "elementary error"). I've historically used S4S in all my work because I did not own a jointer or planer. This is gonna be so much more fun since I'll have so much more freedom -- no longer stuck with whatever the bix boxes have. :D

Thanks again for your help.

Mike

[harry strasil]

Although I think of myself as a Neander, I do own some tailed critters, and use them for some things. One trick so to speak the old time neanders used and it works for a tailed jointer also, was to clamp 2 boards to be edge jointed together face to face or back to back on the edge of the workbench and joint them both at the same time. If there was any deviation from dead square the edges still lined up perfect when they were opened up. The two pieces have to be dead flat on the faces first for this procedure to work correctly and when using a tailed jointer, I clamp them firmly together just above the fence top at each end and in the middle. I am not saying that you should not square the fence with the table, but if there is any deviation it is negated by jointing them both together.
I was fortunate to have a mentor who worked as a finish carpenter in the days before power tools and as power tools became available they were pressed into service. As with machine work the set up of the machine is all important. I know many use a dial indicator to set there knives and as I am a blacksmith machinist welder I have these available for use, but the easiest way for me to set jointer blades is the way my mentor taught me. He used a piece of hardwood 3/8 wide and a foot long with the edges jointed dead flat and a thin pencil line 3 inches from one end, this mark was positioned at the edge of the infeed table and each knife in turn was slowly turned by hand untill it touched the piece of hardwood, both edges of the knife were adjusted so that the hardwood moved only the width of the pencil line when the blade touched and then went past the line up tool. He had an older powermatic 8 inch jointer that you could almost see your face in the infeed and outfeed tables. Until he passed away I was fortunate enough to be able to use his jointer to true up my wood planes with.

just my $.02 worth, I will slide back to the other side.

I will pass on a tidbit of information he gave me from his early days.
Did you ever wonder why there were so many pairs of saw horses around in years past? For the younger generation most of these sawhorses have dissapeared from abuse and neglect. Answer; In the early days when appling for a job a carpenter was required to build a set of saw horses and how quick and how well made they were was the determining factor on whether he got a job or not. the standard set of dimesions in those days were, 4ft long, 2 ft high with the legs splayed at 10 degrees out and 10 degrees toward the ends with the outside of the legs at the ends directly below the top ends.

Jr.