Bandsaw Kerf

[Larry Gottlieb]

Anyone have good ideas of how to get reproducible thicker kerfs with a bandsaw.

I am trying to turn Celtic knots without success.
One method is to cut part way through the angled blank on a sled and then glue in the thin piece of veneer.

I would like to use thicker pieces and need to get a wider kerf.
Any help will be appreciated.

Larry

 

[CrazyBear]

Usual method for thicker kerf is to use a table saw. But if you only have a band saw I would try making your first cut and then place a spacer the thickness of your desired band at the base of the blank where it meets the stop for length, The extra thickness at the base will then give you two paralel cuts and you simply remove the bit in between either with tyhe band saw or with a narrow chisel.
Another suggestion would be to make up a jig for your router and use the thinner straight cutter to cut out your blank.

 

[fernhills]

Hi, If you do have TS i use a plywood blade,gives me a nice narrow kerf but not to wide but just right they way i like them.. Carl

 

[Rudy Vey]

The larger the saw blade width is and the less TPI you have, the wider is the kerf. So, a 1/2" blade with 4 TPI has a much bigger kerf than a 1/4" blade with 10 tpi. A wider blade is normally also a thicker blade. That's at least what I found out. I will also make my celtic knot pens in the future with the band saw - the miter saw (I always used so far the miter saw) starts to scare me.

 

[KenV]

There is also the ability to increase the set on the teeth to alter the kerf size (up to limits). Important is to figure the desired thickness and how to achieve it. Glued up veneers provide quite a bit of choice unless you are setting up a thickness sander operation

Bandsaws over 18 inches tend to have thicker blades also --

Thinner kerf yet -- move to a scroll saw

 

[jeffj13]

Larry,

Maybe I am missing something, but if you cut all the way through the blank, you can use as thick a piece of wood for the knot as you like.

jeff

 

[Ron in Drums PA]

The whole trick is to use a piece of wood that is equal to the kerf of the blade.

If you are using a bandsaw you are limited to thinner kerfs, which don't look bad at all. There is a bandsaw blade that has carbide tips that have a wider kerf, but it ain't cheap.

I guess you can make a jig that you can make one cut than add a spacer and make a second cut. To be honest I really don't know how it would work or if it worth the effort. Lets us know if you give it a shot.

Edit in
http://www.suffolkmachinery.com/1_carbide_blades.asp

 

[Larry Gottlieb]

Jeff,

In the past I have cut through the blank and glued the insert. I have a little problem keeping the two pieces lined up.
What I am trying to do is to cut through the blank leaving about 1/8" and then sliding the glue covered insert into the kerf.This simplifies the glue up.

Today I used a spacer and ended with a kerf of .072" compared to the bandsaw blade of .025"

I,ll see what it looks like when it is turned and report back.

Thanks to all for suggestions.

Larry

 

[CharlesSharp]

You use a stop to locate the blank each time, right?
Put a shim between the stop and blank to widen the kerf (2 cuts).

 

[Larry Gottlieb]

It is getting better, but there is still a visible glue line. I used a spacer between the blank and the stop to give a thicker kerf with the second cut.
The glue line may be due to a thin insert or irregularity in the thickness of the insert. I will keep trying.
This is a scan of the knot.

Larry

 

[GaryMGg]

Larry,
May I ask why you don't use a table saw with an 1/8" kerf blade to do this?

 

[Larry Gottlieb]

Gary,

The bandsaw is much easier for me than the tablesaw. Matching the inserts to the kerf seems to be my problem. This would also be a problem with the 1/8" kerf of a tablesaw.I cut a group of the inserts (veneer) using the bandsaw sled.

I keep getting closer and since this is a hobby there is no compelling reason to turn the "perfect" knot except my compulsion.

Thank you

Larry

 

[GaryMGg]

Larry,
I misread your earlier post wherein you wrote you were leaving 1/8" connected.
I thought you were aiming for an 1/8" kerf, hence my question.
However, if you look at the tutorial I wrote on Celtic knots -- http://content.penturners.org/articles/2007/celticknot.pdf -- I'd expect you can easily adapt my method to the bandsaw. All it requires is fitting the miter sled to the table of your bandsaw rather than the tablesaw. As to making the insert fit the kerf, I get as close as I can, and if I'm off a little I use my planer with a sled or a block plane or a scraper to get the fit just right.
I find using a sharp scraper makes super fine shavings which only adds to the fun of doing the work [][8D]
BTW, I viewed your pens -- Nice work.

Cheers.

 

[Larry Gottlieb]

Thanks for the reference, Gary.

I am using a bandsaw sled to make the angled cuts. I think that when I keep the small amount of wood intact at the end of the cut, this is what causes the problems with the fit of the insert.
In the attached scan, even though the fit of all of the inserts seemed good, there is still a small glue line seen in some places.

I'm getting closer

Larry