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Hope I've got my terminology right but what width should the kerf be in kerfed lining material. I made some on my bandsaw, but the blade was thin and struggled in the waist area. What is a common dimension and what's the opinion on normal or reversed kerfed linings. I know its another apples vs oranges question, just would like to know both sides for future use, may try it in my next build to see which I prefer but lets get no 1 finished first!

Thanks

John

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Formerly JJH

I learn more from my mistakes than my successes

this can vary a bit depending on the width and number of the segments you use to spand a given lenght and the radii need to conform to. The narrower the segments and greater the numer of segments in a given lenght the smaller the kerf can be. reversly the wider the segment and fewer the segments over the same given length the wider the kerf will need to be to bend the radii.

I have some from two different commercial sources, some of it is .02", some is .03".

I believe the reversed lining ends up being stiffer, so that's what I use.

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David White, Toronto

"All my favourite singers can't sing."

John my friend I don't know about the width of the kerf/cuts but I use reverse kerfed linings too and they are much stiffer IMHO as well.

At the moment mine are stiff due to the fact they just touch on the gentler curves round the upper and lower bouts just struggled round the waist area one side started to split away from the uncut section of the lining but it glued back so well I can't now find it!

Thanks Guys as always someone here knows

John

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Formerly JJH

I learn more from my mistakes than my successes

Your issue is not the kerf but the number of segments per inch. If your segments are not seating in a tight bend then you need more segments per inch of lining which in turn will lead naturally to more kerf voids per inch of lining. more segments per inch also leads to narrrower segments.

I tried to make some on my bandsaw too. It seems the tooth-set in the smaller bandsaw blades are very small (even on the 3TPI blade). It caused the kerf to be way too small. I had a hard time using the stuff I made around the waist and cutaway area. I made a new batch on the table saw with a plywood blade. Maybe the kerf was a little to wide, but I had no problems using the linings in the tightest areas of my cutaway. I basically marked the top of the table saw with about 3/16" or maybe 1/4" line. I advanced the material up to that line for each pass of the blade. I cut about 8 strips of lining at a time with a hold down block covering the pieces (and my fingers). All in all it worked fine.

PS: I also dampend the back of the linings with a damp cloth on areas that were tighter. Not wet, but damp. That along with the moisture (water) in the glue seemed to help it bend.

PSS: I also found that Basswood bent easier around the waist than did the same linings made of mahogany. So there could be a difference in the fiber/straning of the two woods. The mahogany seemed to snap apart easier than the basswood.

J

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Joe

If you use reverse kerf on the 8" of waist section, then it can't tear out You don't have to use a continious piece. .

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