Wooden Knife Handles

[Manuka Jock]

If you really think I'm being a nuisance for asking questions, then I can go away.

ron

Ron , if you cut in half every item that you stabilize with oil , how do you explain the glue join to the customer ? ............


If your day to day food bowls are only 4-5 mil thick then they are doomed to failure

The stuff you work with has ceased to be wood mate . It is fiberplastic

Here is a hint . Don't use smelly linseed oil

bye

[ubeaut]

Hop Thief - Have a look at this it may be of some interest Attachment 142046

[labrat]

Hop Thief
I am coming in a bit late as I have only just found this thread. I have been also seeking advice on stabilising wood for use on knife handles.
I have found a couple of bits of information that may be of some help to you.The first is an article"Wood,Oil,and water" by Raymond & Lee Dessy (Google search). It deals with woodwind instruments that need to be protected from musicians who spit down them as they play. It is a good article and describes a number of treatments used by music instrument makers to stabilise the surface against moisture penitration.The author is a chemistry professor and he spells out why they do or don't work.

The next is some advice I was given by a gun stock maker here in Brisbane back in the 1980's. He made a couuple of stocks for me and when I asked about finish he suggested a 50:50 mix of Par-boiled linseed oil and pure turpentine oil(Gum turpentine NOT mineral) The gum turpentine is there to speed up the oxidation of the linseed oil inside the wood, where it becomes semi-solid and occupies space so that water can only enter in very small amounts rather than being filled with water. After warming the wood in the sun saturate the stock and leave in the sun 15 mins a side, wipe off the excess and buff a couple of hours later with a well washed linen cloth (Linen is lint free unlike cotton).Do that once a day for a week then once a month for a year and you should have a lovely finish. I have to admit it looked great and got better with handling,but did not stand up that well in the field.

I have also just purchased some Miniwax Wood hardener from the US (About $30 all up including post) and am going to try and stabilise some AZ desert iron wood in a vacuume chamber that I have. Still waiting for it to arrive, i'll let you know how it goes.

I also bought some 5/16" loveless style bolts from the UK on ebay (Item number 310194683093) the post from the UK is much cheaper than the US. The 1/4 inch ones are too unforgiving as they have a very small shoulder to pull down the wood.

[Rifleman1776]

I do wood stabilizing. My solution is plexiglas dissolved in acetone. I stable under a vacuum. As I understand it, Min Wax wood hardener is the same solution but applied to the wood it does not penetrate. For smaller items it goes all the way through the wood. I plan to use for duck calls. I'll rough turn then bore before stabilizing to save solution and assure full penetration. When stabilized the wood will be very resistant to moisture.

[labrat]

G'day Rifleman1776,
Thanks for that info on the plexiglass & acetone mixture, that sound like it would be far cheaper than the commercial product.
I was planing on forming a small container slightly bigger than the piece of timber to be stabilised out of aluminium cooking foil placing the wood in a small quantity (enough to cover it) of the plexi solution. The chamber I have is a thick walled plexiglass cylinder about 8" diameter and 12" height inside with an O-ring seal under a heavy plexiglass cover. The vacuume pump is an aold medical type used to suck out blood ect in operating rooms.It was from a surplus/obsolete hospital equipment sale. It is very old but seems to have plenty of oomph.
My next questions are, about how long do you leave it in the vacuume and the plexi solution that is not drawn into the wood can it be re-used?
Best regards
Jeff

[Mike Busby]

Hi all, very interesting discussion.

OK from my lengthy military experience (25 years in Infantry) and humped any number of weapons over the years around Australia and overseas the following is what I found with linseed oil penetration.

On SLR (L1A1) butts they are around 2 inches thick and the wood was preserved with linseed oil (standard practice in almost all armies in the world) and the oil had penetrated the entire width of the wood. This was achieved I believe by using hot oil as well as using some form of pressure treatment and soaking for a number of days under pressure. Probably something that might be considered at home for smaller projects maybe. Australia timbers where used in the SLR Butts and the Brens had a mixture of Australian and European timbers.

Bren Gun/L7/Mag 58 butts where similar - full penetration.

Having had the odd weapon butt broken off via use/misuse and splitting from incorrect gas settings/broken recoil springs etc you get a good view of the inner wood.

One downside from linseed oil is that it does make the surface slippery when wet and dust and water builds up a tacky grime layer that can only be removed by being scapped off.

Reoiling with a small pad dipped in linseed oil was all we ever needed to do to bring it back to pristine condition. We used boiling water to clean unburnt proppelant and carbon off the weapons and this also had little if any effect on the wood.

[Rifleman1776]

G'day Rifleman1776,
Thanks for that info on the plexiglass & acetone mixture, that sound like it would be far cheaper than the commercial product.
I was planing on forming a small container slightly bigger than the piece of timber to be stabilised out of aluminium cooking foil placing the wood in a small quantity (enough to cover it) of the plexi solution. The chamber I have is a thick walled plexiglass cylinder about 8" diameter and 12" height inside with an O-ring seal under a heavy plexiglass cover. The vacuume pump is an aold medical type used to suck out blood ect in operating rooms.It was from a surplus/obsolete hospital equipment sale. It is very old but seems to have plenty of oomph.
My next questions are, about how long do you leave it in the vacuume and the plexi solution that is not drawn into the wood can it be re-used?
Best regards
Jeff

Labrat, keep in mind you would be using a solution inside the plexiglas cylinder that is a solvent and dissolves plexiglas. Like trying to put hot tea inside a cup made of ice. Not my cupa....
The Gast vacuum pump I use draws to 23 inches of mercury. Can't equate that with your blood sucker. Also consider the internal parts of the pump, plastic parts will give out eventually from the solvent fumes. I do anticiapte having to rebuild my pump from time to time. When stabilizing pen blanks (3/4"X3/4"X5") I leave in under vacuum 1/2 hour to an hour. I'm not a scientist but I use vacuum only because I know nature hates a vacuum and believe it is easier to draw out air and moisture than to force something into the cells that are already occupied by air and moisture. Maybe a real scientist can support that theory or show me where it is wrong. Until them I'm a vacuum only guy. The solution can be reused but some woods might discolor it.
Hope this answers for you. If not, ask anything you want. If I don't know the answer, I'll make up something.

[labrat]

Rifleman 1776, I also have concerns about the container being damaged. Previously the interior of the container was siliconised i,e coated with a special silicon solution that is largely inert and should help protect the surface at least a bit. One of the things they use this material for is to coat glass so that the material it contains will not bind to or react with the glass.

My background is in pathology laboratory work and I agree with what you say about vacuum Vs pressure. In one of the ways of preperation of tissue sample for sectioning for electron microscopy the fixed tissue is placed in a runny epoxy mix and is placed under vacuum for several hours and this will draw epoxy into every space in the sample and any air is scuked out. Its all to do with gradients, you have a lot of epoxy outside the tissue the system wants to equilibrate so there is equal amounts of epoxy inside as outside the sample and the reverse for moisture/air in the sample it is reduced by a gradient going the other way.. Vacuum just assists this process by reducing the factors limiting flow(back pressure etc)where as pressure is trying to achive the same thing by forcing the material in and trying to overwhelm the resistance the result is often trrapped air. Histology labs have used vacuum for years for this reason. Also it takes a lot of pressure and only a small amount of vacuum.. Try the old black coffe and timtam trick where a hole is made in opposite corners and you suck the coffee through like a straw, easy and tastes great. Now get a mouth full of coffee and try and push it into a timtam , it will not work, is more difficult to do and it won't be pretty.( A tim tam is a rectangular choc coated biscuit)
I am not sure if I am a real scientist or not, as all scientists, physicists, physiotherapiests and radiologists have now been lumped into one big pile and called heath practitioners.
regards
Jeff

[labrat]

Hello Mike Busby, I only have 12 years in the Army and only the first 2.5 in Infantry( I got sick of digging holes then living in them) I also remember the L1A1 SLR, a terrific rifle and from what I hear there is a planned return to 7.62 in some limited way as they are finding the 5.56 a bit light on in some applications. My only experience with5.56 was in the M16 and M16 with M203 attachment. I din't like it much. I was pre Aug and my uniforms were green.As for the Bren gun I can remember my IET in T'ville at Lavarack Barracks and being on the range firing it when there was a torrential downpour of rain that just keept on and on and the only way we could keep the Bren gun functioning was to literally pour gun oil down the mag opening at each stoppage. Our platoon Sgt was Barry Sealy he wanted the practice completed no matter what and it was.

I remember being told that the woodwork was treated with hot linseed oil under pressure. But from experience many people do not differentiate between vacuum and pressure, I would love to know which it was. The idea of treating timber that way really appeals to me and I might give it a go. All I could do is heat the wood and the oil and place it in the chamber. as there is now way to heat after it is inside
Regards
Jeff