Shopsmith Forums

babalaisi wrote:Anyone know whether the fence aluminum extrusion is actually perfectly straight or do I have to incorporate a a "spuh the stop in and lift the traight" board against the face of the fence to get a better or perfect result on a 510? Also, with the tilt stop for the horizontal level, how much in contact with the pin does the screw have to be? Slightly touching or firmly snug against the pin that let you return to the level?
Thanks

Good! Since you are following the documented procedure, let us forge on.

My rip fence is straight but that doesn't mean yours is. Use the straight edge that has been suggested to confirm that the face of the fence is straight (both sides).

The tilt stop is a bit bothersome. When attempting to level the table (90°to the blade with respect to the table) I first use a square to set the table and I then adjust the table tilt stop.

After the stops have been set when I want to return the table to horizontal after having tilted the table, I hold the stop button in while lifting the right side of the table. This holds the table in position against the stop button while I tighten the tilt lock. If you hear the stop button come disengaged there is at least an even chance that the table is not level. Repeat that part of the setup.

Once those stop bolts have been set, they are virtually permanent. I use a bit of lock tight to help ensure that.

I am guessing here but I think what you are saying is you are experiencing a deviation in the " flatness or straightness" of the fence itself. So after truing up the fence to the miter slots at the front and back of the fence your dial indicator is showing a variance as you move it towards the middle of the fence. If this is the case then the issue is how much variance are we talking ? A few thousandths variance is probably normal and acceptable. .010 for instance is a pretty minor variation for woodworking. Above .020 is heading into maybe needs dealing with territory. A more important test would be to rip a two inch wide strip of wood X 2 or 3 and see what the variances are along the cut in each piece. If it is minimal then time to get woodworking. Take the three pieces of wood and line them up on the workbench. If they fit perfectly to each other with no gaps you are probably good to go. Many times I find people worry about minute tolerances that are not relative to woodworking. The purpose here is to create good looking joints in wood which is a visual thing in the end.
Paul

One way to check that the fence itself is straight is to set the fence along the left edge of the miter slot a few thousandths shy of it and run a feeler gauge along the gap between the fence and the edge of the slot. The gap should be the same along the length of the fence if the fence is aligned correctly, or it should increase or decrease steadily if it isn't. If it goes up and then down again or vice versa, the fence is bowed.

john_001 wrote:One way to check that the fence itself is straight is to set the fence along the left edge of the miter slot a few thousandths shy of it and run a feeler gauge along the gap between the fence and the edge of the slot. The gap should be the same along the length of the fence if the fence is aligned correctly, or it should increase or decrease steadily if it isn't. If it goes up and then down again or vice versa, the fence is bowed.

With the rip fence set as you describe (right at the edge of a miter slot), a bow in the fence that is significant enough to be an issue would be very visible.

Ripping:

Nothing it 'perfectly' straight. But what is 'perfect'? That answer is in the mind of the observer. As masonsailor2 has said a few thousands is tolerable.

Now as for differences in the ripped board between the center and the ends, it in more likely that the board is causing that than the fence.

If the edge facing the fence is warped (concave towards the fence) the middle of the ripped board will be narrower at the center than at the ends.

If the edge facing the fence is warped (convex towards the fence) the ends of the ripped board will be narrower assuming the opposite end was held tight to the fence. The board will act like a rocker so the result will vary with the positions the board is held tight to the fence.

As for the tilt stop, heed Dusty's suggestion. The table may be moving as the tilt lock is tightened.

Finally I do not understasnd how the rip fence can affect a cross cut(or, were you referring to vertical angle of a cross cut)?

All that said I suspect your threshold of 'perfect' may be too precise than is typical/necessary for wood working. Are thee the one who previously stated thee were a machinist?

I am thinking (aloud) about all that is being said here.

It seems to me that the width of a board that is held tight against the fence all the while it is being ripped will be equal to the distance from the blade to the fence at the very moment the the cut begins. A warp or twist in the fence will not change that unless the fence is closing on the work piece and that must be avoided for reasons that are safety related.

Don't bring warped and twisted work pieces into the discussion. Ripping irregular stock brings on still another topic of discussion.

Which is why it may be causing his 'issue'.

JPG wrote:Which is why it may be causing his 'issue'.

Which is why a jointer is an essential tool in the shop. Straighten the edge on the jointer and then rip. There is a specific sequence of operations to mill crooked stock to obtain a usable straight and flat piece. Failure to follow that sequence results in less than desirable results.

As much as I agree,,,, and disagree with what is being said ,,,,one thing stands true , a warped ,,,concave or convex ,,fence will cause the wood to bind in the blade until enough wood has passed through the blade to equal out on the opposite side of the fence.

Wen you see burn marks on a cut line especially when cutting wood like cherry , ,,,some thing is terribly wrong .

A perfect,,tight fitting cut,,, doesn't mean that much to some but to others it is a necessity .

The only part of the blade that should be in contact with the wood is the teeth not the face of the blade .
A warped fence in any way will have the blade face contacting the wood .

When working with wood,,or ripping 1/4" thick ,,,,or furniture building ,,,,a few to many thousandths sure does make a difference in quality, one reason I use a lot of hand tools for finish work .

you can tell a piece that was built on a high quality machine and finished by hand from one that has not.
A good fence is a must in my shop .

dusty wrote:I am thinking (aloud) about all that is being said here.

It seems to me that the width of a board that is held tight against the fence all the while it is being ripped will be equal to the distance from the blade to the fence at the very moment the the cut begins. A warp or twist in the fence will not change that unless the fence is closing on the work piece and that must be avoided for reasons that are safety related.

Don't bring warped and twisted work pieces into the discussion. Ripping irregular stock brings on still another topic of discussion.

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Ya cant check a fence with a crooked piece of wood? {:}