Resawing Walnut

[Jhalfa]

I have a quantity of thick (40mm) American Black Walnut to resaw for a table I am working on. The boards are up to 20cm wide, which is at the top end of the capacity of my bandsaw (Record BS300).

I have already used my existing widest blade (3/4 inch 4tpi from APTC) to resaw some mahogony, but the walnut appears to be harder, and I would like to cut down on the amount of planing required after the sawing by getting a blade that will give a better finish.

Any suggestions about the blade I should be using to cut through walnut like butter and give a mirror finish? And more importantly where can I buy it from? I am willing to compromise on the part about the butter and the mirror!

Regards

Jonathan

 

[Pete W]

Hi Jonathan,

Generally you need a pretty coarse blade for resawing (finer teeth won't clear the sawdust from the kerf and pretty soon it stops cutting) so you may not have much joy with changing the blade.

I find that slowing down the feed rate helps smooth the cut more than anything, and if you're close to the limit on your saw's cutting capacity you probably need to be going very slow indeed.

Different tooth configurations (skip, hook or raker) might help, but you'll need advice from someone who knows more about that than me.

 

[Scrit]

have already used my existing widest blade (3/4 inch 4tpi from APTC) to resaw some mahogony, but the walnut appears to be harder, and I would like to cut down on the amount of planing required after the sawing by getting a blade that will give a better finish.

Any suggestions about the blade I should be using to cut through walnut like butter and give a mirror finish? And more importantly where can I buy it from? I am willing to compromise on the part about the butter and the mirror!

Hi Jonathan

The problem isn't the hardness of your timber but as correctly surmised by Pete it's the blade pitch. To saw 8in (200mm) material I'd really start to look at a 2 to 3tpi hook tooth set-up and possibly go to a narrower blade on a thinner steel. A small bandsaw will struggle to tension a wide blade, especially if it is thick and the straightness of the cut is directly proportional to the blade tension in my experience. A hook tooth format will cut more freely than a skip tooth as the gullets are deeper and the set is generally a bit more, too. And going to the lowest tooth count will also ensure that you have a deep gullet to carry waste out of the cut. If you can get a variable pitch blade they genarally cut smooter in deep cuts because they vibrate less (see below)

Getting a better finish, however, is where is becomes a tad more difficult. Free cutting blades by their nature tend to be slightly coarse cutting - that's the trade-off you get between speed/free cutting and surface quality. I'd go for the free cutting and plane one surface before each rip cut on the bandsaw as a compromise.

As a suggestion there is one blade I can recommend capable of giving a reasonable surface finish with free cutting - however it's a carbon steel blade and has a short life expectancy and it comes from the USA - it's called the Woodslicer and is marketed by Highland Hardware. Part of it's success is due to the variable pitch design which reduces build-up of harmonic resonance in the blade during the cut - that translates to less "wow and flutter" or vibration which reduces the quality of the cut surfaces.

Scrit