Unisaw table alignment

[Joe Johnson]

I just bought a used Unisaw with a 50" Biesemeyer fence. It's an anniversary edition (about 9 years old) so I think it's USA made. Anyway, I aligned the blade to within .001" front to rear and then checked the fence alignment. Slilding the gauge (I'm using the Aline-it) along the length of the fence gives a range of plus or minus .005". Is this a normal reading or is something wrong with the fence. I moved the fence to the left of the blade and checked that side of the fence and it wasn't much better.
Thanks
Joe

[Bruce Page]

I have my fence set so it falls away about 1/64 at the rear. If you set the fence dead nuts to the blade you run the risk of burning the wood or worse yet, a kickback.

[Jamie Buxton]

I've got a bessey clone fence. It has set screws which you can use to tweak the angle of the fence. I'll bet your real bessey has similar adjustability.

[Bob Wingard]

I'm not sure, but the way I read the original post, he has a waviness along the length of the fence. If that is correct, the laminate on the fence needs to be replaced. I did mine with phenolic board that I was lucky enough to acquire, and it is dead flat along it's length.

[lou sansone]

I need a little more info, but what are you using to reference the dial indicator? you said that you move the fence to either side of the blade and you get similar readings. There is probably no way the both sides of your fence are similarly screwed up. are you using the saw blade to reference the to? the blade it self will have some small about of run out. personally I would not worry about 5 mills.

lou

[Joe Johnson]

I guess I should have provided more information. I'm checking the blade to the miter slot to the left of the blade and the fence to miter slot on the right side of the blade. I was trying to set the fence parallel to the blade. And I guess "wavy" would be a good description of the measurement I got. After I posted the original note, I went to the local Rockler store with my guage and checked a new Beis fence. It was flat so I guess I have a problem. And both sides of the fence are not flat.
Bob, when you replaced the laminate with a phenolic board (and how did you do it) did it mess up the scale for the fence setting or could you adjust the cursor?
Thanks.

[Norman Hitt]

Personally, I would just lay a long piece of glass or even MDF on a flat surface, and then wet the back of some Maybe 120 or 150 grit wet/dry sandpaper so it would stick in place on the glass/MDF, and then rub the laminate face of the fence back and forth (lengthwise) on it until it measures flat, (as checked by your stated procedure). I don't think I would even worry about .005", but as you said, + or - .005", I would probably want to correct it. The problem is probably that the sealer on the bottom edge of the plywood on the fence sides has deteriorated, and humidity has caused a small amount of uneven swelling along the length of the plywood.

[Bob Johnson2]

Joe
Mine has about the same waviness (sp?) as yours and it's just under a year old, it was that way out of the box. I thought about doing as Norman said but have yet to do it. Actually, until you mentioned it I had totally forgotten about it, that's how much I notice it...

[Brent Smith]

Same wave on mine. I've never noticed a problem with the cut though.

Brent

[Bob Wingard]

I guess I should have provided more information. I'm checking the blade to the miter slot to the left of the blade and the fence to miter slot on the right side of the blade. I was trying to set the fence parallel to the blade. And I guess "wavy" would be a good description of the measurement I got. After I posted the original note, I went to the local Rockler store with my guage and checked a new Beis fence. It was flat so I guess I have a problem. And both sides of the fence are not flat.
Bob, when you replaced the laminate with a phenolic board (and how did you do it) did it mess up the scale for the fence setting or could you adjust the cursor?
Thanks.

Joe .. .. .. I removed the factory faces, then layed out the hole pattern on the phenolic board, drilled and counterbored the holes, then drilled out the holes in the Bies. fance so I could run 1/4-20 bolts clear through, creating a sandwich of phenolic/3"X2" steel tube/phenolic. Never had a problem after that, and I also never laminated the faces of the phenolic. I think that is where you're getting your waviness .. .. .. uneven application of the contact cement they used to apply the laminate.

[Joe Johnson]

Thanks to all who replied. This morning I called Biesemeyer Tech Support and asked them if my measurements were within specs. He told me they check every fence they make before shipping. They use a machinists straightedge and a .008" feeler gauge. If the gauge slips through, the fence fails...if not it passes. So I guess my fence is within specs. So now I'll just go make some sawdust and quit worrying about it.
Joe Johnson

[Russell Svenningsen]

Dev is really the guy to comment on this, but ..........................it sounds to me like your acclimamamminator is off by a few thousands. I recommend you remove the flux capacitor and re-grind its bevel using a collinating, radial-arm end mill. If you don't have one of those, (and I don't know why you wouldn't-standard shop machinery for crying out loud), you could always do this work by hand with any ol' electronic, oscillating spindle gouge, but this isn't the 19th century fella! Take it to a reputable shop and have them use a gas spectrometer to measure it's hyperbolic output. If the anemones are within acceptable limits, then it must be the fractal metacalibatrics that are out of whack a "skosh".

Glad to help!


Russell