Bright white!?!?

[Jason Cutter]

White linen is great stuff - it looks actually a little like aged ivory due to the layers, but a word of warning - when buffing it tends to pick up the the gunk and turns the linen layers a distinct brown / black colour, which may not be what you want of the material. I suggest hand sanding to a very fine grit - 2000 grit if possible, being careful not to get adjacent materials impregnated into it (brass, nickel silver, steel grit) and then hand polishing with a white 3M polishing pad. Its so much trouble I just don't use it anymore. Its pretty though. I prefer the "solid" white materials if I need it.

Cheers.

[Colin KC]

Aaaah, Jason,
Finishing is not gonna be a problem, as the whole ting will be dry fitted & finished before final assembly, in theory, it should go like clockwork
So if I can get the download from Sheffield to work...

[Jason Cutter]

Sweet.

Colin, I've got to be one of the most impatient makers around. Have had much more therapy and will practise patience a bit more ! If there's an option for a quicker working, more convenient material, I'll use it, provided its strong, durable and reasonably good looking.

You were talking about the polyester pearl - Looks relatively good. I got the Black pearl for my wife's knife. Looks remarkably like buffalo horn, not pearl. On a half-new belt ground at full speed (no variable speed here) the stuff gummed up the belt and started scorching within seconds. Gotta use new belts and run slow, or use hand tools - the polyester seems like really soft stuff. Lovely finish and real easy to polish / buff up.

My 2 cents on using epoxy / resin ; I've never been able to get it to set as tough as I'd like. The Micarta type materials are high pressure "cooked" as well, something most of us can't achieve in our workshops. The sheer density of the weave / impregnated materials and the phenolic resin is probably what gives it such strength. Its great for inlaying bordered handles. Just doesn't apply well for heavy duty using knives IMHO.

Cheers.

[Dan Graves]

There has been a lot of talk about man made materials that are white. What about interior ivory. I love it.

[Brett Schaller]

Jason's right, I forgot to mention that it tends to pick up buffing compound. I used a CLEAN buff and 312 LEA white compound to polish it.

[Jan Dox]

The home-made epoxy laminates tend to be softer than the industrial, but depending on the manufacturer they have several grades, which differ in hardness and/or toughness.
They still have advantages over a lot of other materials, depending on the intended use of the knife.
A set of clamps and a heated cabinet (heating by one or two lightbulbs) increase quality and speed of hardening. (Helps also for glueing handles)


Jan

[Jason Cutter]

Jan, again it more or less demonstrates my ignorance about these things, but would speeding up hardening actually increase or reduce the quality of the cure? Of course it would depend on the specific material. I've always been told to let it set in its own time and speeding it up could degrade the quality of the bond.

The 2 part systems I use are Selleys Araldite, Devcon 2-tonne (30minute) and a generic brand of 2-tonne (30minute) which seems identical to Devcon - even the box and the wordings are nearly exactly the same. They are very very tough and tolerate amazing abuse for attachment of handles but is almost too easy to abrade when filed drilled.

One of the knifemaking supply sources is listing Acrylester resin with materials like metal , coloured dust you can mix in for interesting effects, but again I'm not sure if it is strong enough so I'm not yet willing to take the plunge.

Can you recommend a particular 2-part resin that you consider to be hardest ? If it is as strong as polyester pearl, it might be a viable alternative to colour.

Thanks.

[Jan Dox]

Jason,

I'm not familiar with American or Australian brands of producers of
epoxies or other thermohardening resins.
The way you describe your epoxies they sound more like glue-types.
I don't use 2part epoxy"glues" for the laminating (or impregnating
cord wrapped handles) but specific "laminating" epoxies. These are used for the industrial laminating of carbon fiber or glass or Kevlar fiber in technical components or body parts of any kind of vehicle ( bikes, cars, boats etc) .Most manufacturers have at least two grades : a gel coat (applied to the mold that will be the outside surface of the product when it comes out of the mold) and the laminating resin( used for the laminating of the carbon (or glass,kevlar,cotton...)fiber textile ). The brand I use has the gel-coat a bit softer but tougher than the laminating resin itself. Some resins remain "sticky" but the gel-coat, being a finishing-coat doesn't.
The epoxy glues I use for attaching my handles feel softer than the laminates I made. The epoxies for the laminates cure in about a day and reach full hardness and strenght in 7 days .
In a heated cabinet they cure a couple of hours.
I'm not familiar with acrylesters but I 'm gonna ask my supplier
and check the library and the Net if we can find out more about their strenght, hardness etc.
I know the industry somtimes uses additives likes small glass balls f.e., to make the surface more abrasive resistant but that might be hard to apply to knifehandles.
The heated cabinet gives a more ideal curing temperature (25 to 35?C or 77 to90?F) than room temp or the average temp in a cool workshop.(we don't want to bake a cake here)

Jan

[Colin KC]

Thanks for the heads up Jan (I was gonna start getting down & dirty with some old t-shirts & Devcon 2-ton )

Just a thought on those glass beads, you may consider looking for a shotblast supplier & asking about a small supply of glass beads to give it a try (they will have a silvery grey look & feel really silky to the touch, & watch out, they get everywhere )

[Jason Cutter]

Many thanks Jan.
We may be getting a bit off topic here, but there was a maker around (is he still around ?) who was coating his handles with grit or sand mixed in epoxy for a REALLY rough feel. That sounds like a similar idea, but the glass beads seem a little more "friendly" to the hand.

On the issue of whiteness, when I back fill antler handles, I use Devcon 2-tonne, but previously had problems because it became very runny in hot weather ( which is also a good thing at times) and it would seep out / spill easily. I have been mixing in an equal part of the powdered glass fibre which thickens it and also makes it a translucent white, which when sanded down, can mimic the surface appearance of the antler. It seems to also strengthen the epoxy a bit in final cure, which I didn't think would happen. I was purely after a cosmetic effect.

Thought I'd throw that in even though it hasn't come out truly white for me.

Cheers.

[Jan Dox]

When the laminating resins (or the components) are a bit to thick
my supplier told me to warm them in hot water instead of using an appropriate thinner. (depending on the sircumstances)This was after the impregnating of a braided cordwrap handle on a dirk failed and I had to cut the outer layer of and start over again. But once the curing started it's faster when warmer.

Jan:cool:

[DiamondG Knives]

Jason, what type of glass powder are you refering to? And where can it be obtained? Im very intrtested, I hate having that raw pithy end showing, and would like to find a way to seal out the look as well as the elements!

Thanks

Mike

[Mike Hull]

Mike, I believe he is referring to glass bead blast material. You can get it at some knifemakers supply houses, or look up abrasives supplies in the yellow pages. They usually stock the stuff.
#BT-8, 60/100 mesh should be fine.

Edited to add, I think I read the post wrong. The white powder you need to color epoxy, is available from K&G. I think this is what you are referring to.:confused:
http://www.knifeandgun.com/catalog/c...6_products.htm

[Colin KC]

In my younger days, I saw some action in a plastics factory & I vaguely remembered something about re-processing polycarbonate (in another part of the works) & what they used.
It was titanium dioxide (the stuff that cleans you teeth in toothpaste, it's very hard & very white (great for taking most marks off melamine faced furniture))


BUT, they also used (to add the bright whiteness) something called "blue tint"

This made a real difference. Without the tint, just titanium dioxide, it looked white but dull (@ 350g for 25Kg, I think) but add 7.5 grammes of this blue tint & BING , the brightest white, anyone know what it is?

[Jason Cutter]

I often don't know the exact names for things as I tend to pick up unrelated materials and experiment with it. In short, the powder is apparently a micronised glass powder which comes with fibreglass repair kits. The kit comes with the fibreglass mesh and woven matting, the 2-part resin and this powder. When mixed in about volume for volume it really thicken epoxy (2-ton Devcon) and makes it a creamy off-white colour. To make it actually match the colour of stag / bone, you have to use almost 1.5times the volume of the epoxy you are mixing. Be careful, it "puffs" everywhere if you try to mix it too quickly. I leave it extra long >48hours to be absolutely sure it sets before I start sanding it back - takes a beautiful polish and can be used also to repair "accidental" pin holes in antler.

Cheers.