Handle Finish

I typed out a pretty lengthy email to a customer earlier today and then started thinking about how this might make for a nice discussion for this sub-forum. I copied the email I sent him and made a few tweaks to it to make it a bit more general in nature...



Handle finishing is something that I never would have thought I'd get into, and certainly not to the degree that I have. When I first started doing rehandles I didn't know (or care) what woods were what, what properties woods had, or how to finish them. I used to do what a lot of knife makers do...."buff is enough". Next!

That approach is fine for safe queens, knives that won't ever cut anything. But that's not to be expected from a kitchen knife owner, they use their knives - all their knives, almost without exception.

The problem for our little sub-world of knife making is that we make knives that will get used hard, washed with dish detergent, get all sorts of crap on them, and maybe even get scrubbied! Basically they get used and abused just from simple normal use.



Early on I came across some wood that challenged the "buff is enough" concept to where I couldn't even get them looking nice enough to impress for the initial customer contact let alone long term use so I started looking for ways to make my handles prettier. This is what stared the ball rolling into what has become an obsession with me.


I've bought likely 90% of everything available on the commercial market that is sold as a finishing oil. I'd bet that I've spent somewhere between $700-$1,000 on different oils and related paraphernalia. I've mixed my own combos from these oils and I've been testing and keeping records since at least 2010 but not until just recently do I feel that I've made any significant progress in achieving my goals of making a more attractive handle that is also wear resistant.


There are several discoveries that have come my way. I've discovered that every wood needs something different, there is no single answer to what to use for everything. In knife making we use hardwoods, soft woods, stabilized woods, oily tropical woods, oily desert woods and these all need something different.


I often get asked about what I do to my handles but I won't answer this question because I'm still learning.
In the past had I said that I do this or that I'd have been giving bad advice for what I know today to be wrong. If I can ever get to where I feel more confident I'll make a post or write a blog or something with specifics to help others out but that's not going to be today.

I will, however, share some of the things that I've learned that I feel are things that are safe to pass on at this point in time....

• Off The Shelf Oils
  
  Most all of the finishing oils on the market are blends that are based off of either boiled linseed oil (BLO)(which isn't really boiled at all) or some type of tung oil variant but rarely pure tung oil (PTO). Some have varnishes or urethanes in them and most contain heavy metal dryers.
  
  Ex. - Teak oil, Teak Oil Finish, Danish Oil, Tru-Oil, Tung Oil Finish, Tung Oil, Circa 1830/1850, Antique Oil, Waterlox, Tried & True, Finishing Oil, etc
  
  These off the shelf blends work OK for most applications but fail for some. I could write novels on the combos I've tried and the results I've achieved but the take away is that they don't always work, or better put, they don't always match up to the wood being worked on.
  
  Most failures come from the fact that they don't adhere well enough, aren't water resistant, or cloud the grain/obscure the beauty.
  
  
  
  
  
  
• Mix Your Own
  
  I now prefer to mix my own blend. This allows me to tailor the blend to suit the needs of the particular wood being worked on. Maybe I want to have a high level of shine, maybe I want a satin sheen, or somewhere in between? One day it's a hard stabilized wood like maple that I'm working on and the next day it's oily African Blackwood, there's many variables to consider. I like to be able to make the necessary changes on the fly vs having to follow what a can has in it and hope for the best.
  
  
  
  
  
  
• What to Use on What
  
  There are two (basic) distinct categories that I break wood into when deciding on the blend that I'll be using.
  
  
  1. Non-Oily Woods = Oil/Varnish Blend
  
  2. Oily Woods = Wiping Varnish Blend
  
  
  
  Oil/Varnish Blend = BLO or PTO / Thinner / Varnish
  
  *Note - if you're going to use tung oil be sure to buy "PTO" - the more expensive "Pure" or "Raw"version.
  
  **Note - PTO has no dryers and takes much longer than BLO to fully cure. PTO is superior to BLO in the results it provides but you need great patience to use this stuff. Be sure to keep this in mind when adding coats and before use.
  
  
  Wiping Varnish Blend = Thinner / Varnish
  
  *Note - I've never tried this but many people use shellac on oily woods. Shellac drives me insane but has great waterproofing qualities and because of that it's still something I'll be working with in future testing.
  
  
  
  Adjusting the blend
  
  To achieve more shine - add more oil.
  
  To get more water resistance - add more varnish.
  
  To make the mix flow/spread easier/better (or even soak in better) - use more thinner.
  
  
  
  
  Then there's....
  
  Poly = Don't bother unless you want plasti-dipped handles. This stuff can substitute as varnish but will be more plasticky than spar even. I believe this is, along with BLO, the main ingredients in Tru-Oil
  
  Lacquer = Cheap looking, like you spray painted the handle
  
  
  
  
  
  
  
• How Many Coats?
  
  Use many very thin coats vs a few thick coats!
  
  I've found that 5-6 really thin coats to be the magic point where I start to like what I see and can expect it to not wash off too easily. More is better though you can expect to at some point cross over into a bit too much with some woods. I define "a bit too much" as to where the handle looks and feels gaudy. There is sometimes a fine line between a nice build up that's glossy and the "old ship's deck" look, know what I mean?

So, have I just given you the answer to how to finish your handles? Well sort of. If you were paying attention you should have realized that I've labeled the basics but that you're going to have to play around and figure out what works best with different woods. There is no one simple answer here, not if you want really nice results anyway. I do hope that what I have given you here helps some.

I'd love to have some further discussion on the subject as I don't mean for my post to be the end all on the subject. I'd like to hear what others are doing and have learned, maybe I can learn a new trick or two.

Dave

 

Good post and discussion Dave. I will have to try out your suggestions sometime in the future when I branch out into other woods.
The only finish I've tried other than Boos block board cream is CA. CA comes out ok, but I don't prefer it as I think it may have issues long term

I tend to use ironwood and the blackwoods which as you know are oily woods. On these I use the Boos cream. It penetrates so good water proofing, and I think the more natural oils and bees wax would tend to preserve the wood long term. This is easy to maintain over time too. Just rub in some new oil every month or two and it's as good as new.
I usually give a good buffing on this, then re-oil. This should help the wood stand up to washing and scrubbing. It is going to get a use patina for sure, but I think this adds to the knife character and it should still look very nice throughout the life of the handle.
This should also keep the wood from shrinking over time.

On stabilized wood I oil and buff the same. The oil probably doesn't do too much in this case, but it makes the buff nice.
Do you used stabilized woods? If so, what is your routine on these?

 

Hi Mark,
You brought up a good point and that's about the user's maintenance. This is something that we don't discuss often enough. I feel that we should either provide a durable no maintenance (or as much as is reasonably possible) finish or a finish that can be maintained like what you're describing with the oil/wax mix.

For ironwood specifically, this is a tough nut to crack if you ask me, because I've seen a lot of really ugly ironwood on kitchen knives. I suspect that they didn't start out this way. I've asked some of my own customers to provide details on how my ironwood holds up over time and it's been a mixed bag of failures and successes, the bulk leaning towards failure. The thing is that ironwood oxidizes and it can be rapid when exposed to moisture and especially UV light. I know that UV plays a big role in this problem because I've seen two different ironwood handles where one side was brighter/cleaner than the other and when I asked each customer they told me that they use a magnet bar in their kitchen which exposes only one side of the knife to UV light.

I've tried all sorts of concoctions on ironwood and found that the only way to slow the oxidation is to keep the knife out of light when not in use and to seal the handle under many coats of spar urethane. The problem with using spar is that it's thick and clouds the grain taking away lots of character. I suspect that shellac might do well on ironwood but I currently lack the patience to play with it again.

I used to do the boardwax and buff routine on ironwood myself and I may return to this method if I can't get a reasonable result from a hardening finish. Why bother going to all the trouble to finish this wood if it's just going to oxidize anyway?

As for blackwood, this stuff takes wiping varnish nicely, and I find it to be a good route to take with this wood. It doesn't need to be sealed, the finish seems to hold the nice look longer by protecting it from scuffs and scratches. I don't see any problem with using the boardwax buff routine on this wood either though.


Yes I do use stabilized woods. In fact everything that can be stabilized I insist on having stabilized. My routine for stabilized woods is pretty much the same as non-stabilized woods, it's just that stabilized takes in less oil meaning less coats required. Some stabilized woods will still take in a whole lot of oil though, it simply depends on the quality of the wood itself really. For these woods I use the oil/varnish blend. I start off with more oil & thinner in the mix to get it into the wood and to fill the pores and towards the end I shift the ratio towards even parts oil/thinner/varnish to seal the wood's surface for water protection. That's a general guideline though, you really need to tweak as you go based on the results you're achieving.


Thanks for jumping in here and describing your methods and asking questions too.

Dave

 

I have to say that even as a user I find this thread very interesting, especially the tip about ironwood and UV light might be pure gold. Would this apply to other woods as well Dave? For example rosewood?

 

I don't know about that but there must be something to this because so many of the marine grade wood treatments have UV filters in them.

 

Thx, this is very relevant to me as in my apartment back in Cuba sunlight hits everywhere in the kitchen.

 

I get a lot of my ironwood in at garage sales as native carved statues. Almost always it's very dark. Cutting and sanding it is what brings back the grain and lightness, so UV is a big factor with ironwood.
I think Manzanita is somewhat similar, but doesn't darken as badly over time. I have a 16 year old piece I worked and it hasn't darkened much.

 

I've found Cocobolo to be similar to Ironwood in this regard — it will darken over time. And at some a super nice Cocobolo figure might turn into ugly muddy-black something. No idea how to mitigate that other than do periodic cleaning of handle with some very light abrasive (like 3M paper).

I don't think shellac is a good option for kitchen knives handles, cause it doesn't play well with water. I'd love to have access to spray camera and try lacquer, because I'm very impressed by some guitar makers that use lacquer for some amazing looking results… and it might be a tad more durable comparing to the oil.

 

Thanks for your input on cocobolo Anton. I've never made a handle from it so it's a complete mystery to me.

 

Hi all - newbie Q - I use a lot of Blackwood and Paduak and for scales all's good with tru-oil -> renaissance wax finish but I've recently been working on wa handles and the end grain stain retention for the Paduak is so high I'm toying with 1000 grit finish -> renaissance wax - any pronouncements appreciated - Thx -M

 

Looking forward to seeing some of your work Mark.

Sorry I have no finishing tips for you.

 

I'm not quite sure what your question is. Could you clarify?

 

Oops ...apologies for the lack of clarity ...basically am looking at options to minimize increased oil uptake by the Paduak endgrain other than using a very find sandpaper seal and then wax finish which is what I'm testing out now. Hope that's better -Thx -M

It's for the two wa handles in the pic...if I got the upload right anyway

 

Oh, so you're using some edge grain and some end grain together? Hmmm, maybe try a sealer on the end grain first? That probably won't work though, I suspect it'll still take a lot in.

Alternatively, why not try skipping the oil and using a wiping varnish instead?

That's all I got.

 

Mucho Thx - will look for some wiping varnish and go from there - M

 

Wiping Varnish Blend = Thinner / Varnish

 

I have not tried this myself but a couple high end knife makers that I know use this sealer for coarse grain or end grain wood followed by the tru-oil gunstock finish.