Jointer blade update

Update:

Took the dial indicator home this weekend. It is in metric and one mark equals .01 mm. Something was wrong with it though because I could not turn the magnet off.

Is it best to try and use a dial indicator to set the blade height or is it acceptble to just use a block of wood? If I use the dial indicator to set blad height how do I do it? Do I zero the meter at the outfeed table and then raise the blade to equal zero on the indicator when using it on the blade at the highest point? I guess the question I have is if I were to measure the end of the outfeed table closest to the blades going the entire width (6 inches or so) I get different readings. Should I just use the highest readind and use that to determine blade height? Or should I pick a spot on the outfeed table next to the blade exactly across from it and set the blade to that height?

It was frustrating because that thing is hard to pull around with the magnet not turning off. I am thinking of just breaking down and buy one in standard.

The first blade I just set by raising it to a block of wood. All ends of the blade touch the wood. But it seems the middle may be a slightly different height than the ends for some reason. The blade will actually move the wood a very small distance in some places on the blade and touch but not move it at all in others.

I also tried magnets but there is not enough room to tightne the allen head bolts holding the blade on while the magnet is holding it. I tried everythign I could think of but the screw holes are under the machine when the knife is being helt at its highest point.

I just want good enough accuracy to have perfect fitting edges so I can glue up pannels and do some face planing on small boards.

ANy advice is greatly appreciated!

Reply to
stryped
Loading thread data ...

stryped,

Please post some pics of your projects to abpw so we can better understand how important the tolerances are that you are questioning and trying to achieve.

jc

Reply to
Joe

Reply to
stryped

Here is what I have found, others may differ. If the blades are above the outlet table, even a few thousanths, you will never get a board flat. For me, the only to assure equality in height is with a dial gage. The dial gage is also very helpful for getting the three blades in the same elevation and parallel to the tables. Dave

Reply to
Dave W

Okay, I'll differ on both counts, while acknowledging that YMMV.

While "a few" thousandths may be too much, a very slight bias higher than the table is advantageous, for a couple of reasons:

Look at a jointer cut. It is scalloped. The height of the blade at TDC cuts the bottom of the scallop, while the board on the outfeed table is resting on the peaks between cuts. So to have a perfectly straight cut, the outfeed table should be lower than the blades by the depth of the scallop. And on this basis, you should vary the height of your outfeed table based on the speed with which you are pushing through material--but we are WAY beyond practical reality here! For a second reason, the blades are wear items, while the tables are not. Cutting will shorten the knives, and if they start out dead level with the outfeed, soon they will be lower, and your work will catch on the outfeed table. For the third, and most important reason, it works better for me. Also, high knives means any spring in the joint will be in the center not the ends, which I prefer.

As far as setting, I've found using my dial indicator to be a PITA. I get every bit as good results with a straightedge resting on the outfeed table, observing how far I drag it as I slowly rotate the cutter head through blade contact with the straightedge.

Reply to
alexy

Reply to
stryped

Approaching none. The best I have been able to accomplish is around 1/8".

My jointer preforms well (no light between edges) with this level of accuracy.

-Steve

Reply to
Stephen M

To determine ideal, I'd have to do the same thing you would--check a book in the library. But I don't think "ideal" is as important as consistent--from end to end of each knife and from knife to knife. FWIW, mine drags a straight-edge about 1/8". If my cutterhead is about

2" in diameter, that means my knives are about .002" higher than the outfeed table.

That works well for me on my machine. You'll have to find what works for you on your machine.

Reply to
alexy

Doesn't this device have a permanent magnet? You can't turn such a magnet off. If it is an electromagnet, which is unlikely, you just disconnect it from the power. Jim

Reply to
Jim

Now you're going to have to calculate Stryped's ideal drag on his cutterhead with 2.5" diameter. Then he'll post that his straight-edge drags about 1/64" less than that amount and will want to what to do to fix it and if it is OK. Of course after he asks where to buy a straight-edge.

Reply to
RayV

Some have a lever on the base that you turn to de-magnetize the base. I guess it just pulls the magnet away from the bottom.

formatting link

Reply to
RayV

Some of these magnetic bases have a lever that moves the magnet up inside the base to release the grip -- perhaps that's what he's talking about.

Reply to
Doug Miller

LOL!

Reply to
alexy

how much mechanical advantage there is. Turns out it is a cleverer arrangement than that. Here's the wikipedia explanation:

formatting link

Reply to
alexy

Reply to
Doug Miller

Reply to
stryped

The knob probably came loose from the magnet.

Reply to
Doug Miller

Or the table is magnetized :)

Reply to
dadiOH

"but its advantage lies in the fact that there is only one mechanism (screw) to loosen or tighten the arrangement making it easier to use, unlike the other where a third hand is often wished for."

Ray wonders what he would do with a third hand...

Reply to
RayV

Just watch this guy:

Bob Vaughan has probably set more jointer knives than the rest of us combined.

Reply to
Joe Wells

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.