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skiajl6297
02-22-2013, 09:53 AM
I bought a well used Blazen 240 on this site, and it was in excellent condition on arrival. I have been enjoying learning to sharpen, and really just going to town on all kinds of home chopping work. I love the knife.

The other night, I noticed that the tang is protruding over the scales, just ever so slightly - so that the full tang metal is now feeling slightly raised over the scales. Aside from rehandling (which I am sure is a great option based on the work I see on this site) is there any way for me to fix this at home? It isn't a huge deal, but I am noticing that it makes a difference in my day-to-day use when things don't feel polished and completely flush.

franzb69
02-22-2013, 10:00 AM
hmm if the scales are made of wood, perhaps dipping it in mineral/linseed oil for a day or two would help.

ThEoRy
02-22-2013, 04:29 PM
What kind of wood is it and where do you live? Is that even wood or is it a micarta/laminate?

skiajl6297
02-22-2013, 05:26 PM
Unsure what type of wood, but looks like wood. Live in Maryland. Can't seem to figure how to load pics but have some good samples.

Dave Martell
02-22-2013, 05:31 PM
Japan is very humid (where the scales are installed) and wood tends to shrink in many parts of the USA and different times of the year makes the problem even worse. It sucks, not something any of us like, but it's very normal.

chinacats
02-22-2013, 05:38 PM
Japan is very humid (where the scales are installed) and wood tends to shrink in many parts of the USA and different times of the year makes the problem even worse. It sucks, not something any of us like, but it's very normal.

Does the wood being stabilized help to prevent this?

Chefdog
02-22-2013, 05:40 PM
Japan is very humid (where the scales are installed) and wood tends to shrink in many parts of the USA and different times of the year makes the problem even worse. It sucks, not something any of us like, but it's very normal.

Will the standard pakkawood type scales respond to soaking in mineral oil? I guess there's no potential harm in trying right?
I have a Suien gyuto that I got a couple months ago and it's got just the slightest bit of shrinkage too. I'd rather not go at it with the sander if I don't have too.

OneStaple
02-22-2013, 05:47 PM
I'm just a beginner with japanese style knives, but I am a woodworker. Wood will expand/contract with changes in humidity, so if the scales were put on in the humidity of Japan and then brought to Maryland where it's fairly dry because of winter, you'd expect some shrinking. It may expand back out in the summer with Maryland's humidity, but of course air conditioning cuts back on the humidity within the house.

Any finishes on the wood will slow the rate of expansion/contraction, as it is harder for moisture to be absorbed by the wood. How much it is slowed or if it is stopped completely depends on the finish. Most finishes to not completely seal the wood from the air/humidity.

I don't really work with "stabilized" woods, but from my understanding (feel free to correct me if I'm wrong), the wood is filled with polymers or resins (often through a vacuum process) to almost plasticize the wood. That adds strength to a weak piece of wood and minimizes or eliminates any expansion/contraction. Of course, that assumes that the stabilization process was done correctly. It should help with making the scale "waterproof" for kitchen use as well.

Hope that helps!
Tyler

skiajl6297
02-22-2013, 05:50 PM
Great point on humidity inside. Heat constantly running and bone dry indoors. Would certainly explain it. Thank you all!

Dave Martell
02-22-2013, 05:52 PM
Does the wood being stabilized help to prevent this?


It can still happen but it's rare. What we see with stabilized woods (sometimes) is that you can feel a bulge from the steel bits if the wood shrinks vs that sharp edge steels bits like you do with factory scales so it's a much less pronounced problem.

Dave Martell
02-22-2013, 05:53 PM
Will the standard pakkawood type scales respond to soaking in mineral oil? I guess there's no potential harm in trying right?


I'm not sure but like you said there's no harm trying it.

OneStaple
02-22-2013, 05:55 PM
A couple more thoughts...

Different woods/scales will expand/contract different amounts with humidity than others, so some scales are naturally less prone to shrinking than others, although all will do so to some extent. Also, woods expand/contract at different rates in different directions, so the orientation of the grain can make a difference also.

Mineral oil is a finish that never hardens in the wood. It is a good food-safe finish (great for cutting boards, for example) and easy to apply, but must be replenished regularly (especially if the wood is washed) and won't do as good of a job at sealing wood against expansion/contraction as other hardening finishes. It still helps though. And of course you'll never see it delaminating from the wood surface or chipping off.

Tyler

kalaeb
02-22-2013, 07:11 PM
I live in a climate where everything shrinks. Sometimes I will just sand the tang a bit to ease the feel of the shinking scale. I have never had one bounce back with mineral oil, but like Dave said, it can't hurt to try.

ThEoRy
02-22-2013, 08:33 PM
If it is pakkawood then it's just a laminate. Not sure how much a mineral oil will help/penetrate but you could try it. If you have access to a cryovac machine you could always try to vacuum the knife in the mineral oil on high pressure to try and force it in there a bit. I do this on regular wooden handles and sayas to great effect.

franzb69
02-23-2013, 12:03 AM
good idea! =D

Mike9
02-23-2013, 07:41 AM
The scales on my Hiro shrank and the tang was sharp so I replace them with Ironwood. I have the same problem on my Hankotsu so that will be getting new slabs soon.

samuelpeter
03-03-2013, 10:48 PM
I just noticed the "resin-stabilized" scales on my old Tojiro shrank significantly. Depending on your climate, it can happen to lots of things. It sounds like you now have a good excuse to rehandle!