LumberJocks

Cutting Frozen Lumber

  • Advertise with us
Blog entry by Emily Whitman posted 02-06-2009 12:43 AM 819 reads 0 times favorited 5 comments Add to Favorites Watch

When cutting thoroughly frozen wood, you are essentailly cutting hard ice reinforced with wood fibers.

One of the factors that changes is the composition of the sawdust and the way it moves out of the gullet. A gullet that operates well in warm cutting will not be able to hold any material at all during frozen cutting. The sawdust changes from chips to slush to a very fine dust.

In normal sawing you are cutting through a lot of individual strands. Once a strand is cut it doesn’t hinder the next cut. Cutting frozen material can be a lot more like sawing fiberglass. The material wants to grab the side of the saw.

In frozen wood the saw makes a very fine dust instead of the kinds of chips normally associated with sawdust. This very fine dust does not load the saw gullet as does normal sawdust. Instead it can pass down either side of the saw. A saw is designed to have a loaded gullet while in operation to create dynamic tension that helps keep the saw running straight.

Without the loaded gullet and with the extremely fine dust passing down one side of the saw or the other there is more pressure on the saw to move sideways.

The most common solutions to sawing in colder temperatures involve slower feeds and speeds, changing the gullet design, decrease tip exposure, or switching to a tougher grade of carbide.

Changing the gullet design as the temperature drops: At slightly colder temperatures the gullet is re-designed to more easily move the material out. At coldest temperatures we are back to the original gullet design but there is an extra notch cut to trap the very fine dust. The notch creates a plug that traps the dust. The dust will build up and help maintain the dynamic tension.
Tip loss can be a problem with frozen lumber. Tri-metal shims can give a significant increase in performance as can heavy duty wire solder. Tri-metal shims do leave a copper layer that has to be ground out when a tip is replaced but they do work extremely
well.

Decreasing tip exposure: If a normal tip to shoulder dimension is .032” then it has been recommended that perhaps a tip to shoulder dimension of .020” is more suitable for cold weather. This may not sound like much but it reduces the amount of leverage being applied to pry the tip out of the socket. The amount of force is directly proportionate to the length of the lever. This reduction in tip
exposure means a reduction of approximately 35% in the amount of force trying to pry the tip lose.

Finding a tougher grade of carbide: Tips don’t necessarily get pried lose. Sometimes they shatter and it looks like the tip came out clean. Mills have successfully solved this problem by switching to a tougher grade of carbide such as Cermet II or a nail cutting grade.

-- Thanks- Emily, Washington, www.carbideprocessors.com



5 comments so far

View Karson's profile

Karson

35035 posts in 3861 days


#1 posted 02-06-2009 01:37 AM

Thanks for the info. Now if you can tell where I can get a saw cheap. I’m ready to go. Because the wood around here is very cold. Maybe close to frozen.

-- I've been blessed with a father who liked to tinker in wood, and a wife who lets me tinker in wood. Southern Delaware soon moving to Virginia karsonwm@gmail.com †

View john's profile

john

2362 posts in 3843 days


#2 posted 02-06-2009 01:46 AM

Frozen wood can be cut easy with any cheap blade. It,s just as easy as cutting wet wood .

-- John in Belgrave (Website) http://www.extremebirdhouse.com , https://www.facebook.com/groups/extremebirdhouses/

View SCOTSMAN's profile

SCOTSMAN

5839 posts in 3046 days


#3 posted 02-06-2009 01:49 AM

I would have thought this would be dangerous chances of binding on the blade etc what do you think ? Alistair

-- excuse my typing as I have a form of parkinsons disease

View 8iowa's profile

8iowa

1546 posts in 3222 days


#4 posted 02-06-2009 01:57 AM

Looks to me as if this would be a great time to heat the workshop.

-- "Heaven is North of the Bridge"

View dsb1829's profile

dsb1829

367 posts in 3088 days


#5 posted 02-06-2009 10:05 PM

Call me a wuss, but if it is cold enough for wood inside my shop to be frozen I am gonna be inside by a good source of heat ;-)

-- Doug, woodworking in Alabama

Have your say...

You must be signed in to post the comments.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com