For Lucky¡¯s overhang method, I just use a block of wood with a pencil mark indicating the cut line. Push block against end of the slider and at least cover the pencil line with material being cut. Quick and easy.
I also installed an overhead laser to assist with the first rip on rough lumber. It used to be overhead on my KF700 and worked great but it is on the wall perpendicular to the saw now for my K975. It is not in line so it casts an oblique line. This means it only works if it is calibrated with same thickness as the mattering cut. On my list of things to fix.
toggle quoted message
Show quoted text
On Oct 28, 2024, at 8:58?PM, David Luckensmeyer via groups.io <david@...> wrote:
?
Hi John:
?
You make good points about both the use of a bandsaw and thicknessing on edge. And with regard to the slightly ¡®out of square¡¯ issue. It is very minor like you say, but enough to notice. When it matters (e.g.
for gluing up, joinery work, kumiko, etc.) I will always make two rip cuts. The first cut is slightly wide, and the second cut for that perfect rip where the material does not ride up on the slider.
?
(Yes, yes, I know this is hard on the blade and is probably a bad habit. But it works for me.)
?
There is another technique that I¡¯m not sure has been mentioned much on FOG. I sometimes parallel rip on the slider without a parallel fence by measuring the overhang of material. Here are the steps:
?
- Take any material, clamp it down to the sliding table, and cut it with the blade intended for ripping (e.g. 3.2/2.2 x 30mm).
?
- Do not unclamp the material. Now take a steel ruler or callipers and carefully measure the overhang of material in relation to the right edge of the
sliding table. For my saw, Kappa 400, the overhang is exactly 5.5mm. This is the distance between the right side of the sliding extrusion, and the left edge of my 3.2/2.2mm blade.
?
- Armed with the offset of 5.5mm (or whatever yours is), and with the slider retracted, place the first edge of whatever you¡¯re trying to dimension on
the slider and position it so it overhangs by roughly 5-6mm off the right edge of the sliding table.
?
- Clamp the board in place and use an accurate steel ruler or callipers to measure the offset. If it is less than 5.5mm, then the blade will not cut. If
it is 6mm, then the blade will remove 0.5mm of material. You get the idea (hopefully).
?
- Both ends of the board must be checked to ensure it overhangs by more than 5.5mm. Adjust as needed and reclamp. Make the cut.
?
- If you¡¯re planning on a trim cut only (i.e. not taking off much), make sure to account for any bow in the material. If the bow is outwards or convex,
then the blade will engage at either measured end, and simply take more stock out of the middle (where the bow is largest). But if the bow is inwards or concave, you need to make sure the entire length of material is overhanging the slider by more than 5.5mm.
?
- I do this procedure where I don¡¯t have a lot of width to work with and I want to trim the minimum amount to achieve a straight line rip. If there is
plenty of width, I just eye-ball it. I guess some of us (not me) have a laser and just use that.
?
- If the stock is not too long (e.g. less than 1200mm) I simply set the rip fence and parallel rip in the conventional way. I¡¯m assuming a small sample
size here. It is far less tiring and safer to take the time to set up proper parallel fence/s for repetitive rips for larger jobs.
?
- If the stock is long, say 2-3m, but I only need to rip one, I¡¯ll do some mental arithmetic and do a parallel rip on the basis of the overhang amount.
I can get very close using this method (at least down to 0.2mm). If the board has to be exactly parallel, I always break out Brian¡¯s parallel fence, calibrate it using my magnetic ¡®calibration device¡¯ so that it agrees exactly with my cross-cut fence stop.
And parallel rip that way.
?
Again, I hope this helps.
?
?
Another method for ripping is skipping the circular saw, ripping to slightly over width on a band saw, and running the boards on edge through a thicknesser. That idea has been presented in this group before,
so I do not take credit for it. I struggled with that idea until I acquired a band saw that would make clean and straight cuts.
Once a board is flat and uniformly thick, I will joint one edge and rip a piece off the edge. If ripping several pieces from one board, I just keep jointing and ripping until done.
When my saw was new and I was still trying to use it like a cabinet saw, I found that the slight difference in elevation between the cast iron and the slider was enough to throw the cut edge out of square.
Not by much, but by enough to be noticeable in some cases.
John Hinman
Boise ID
K700S and A941
imran