Thread: Making a rasp for saw handle shaping

May I suggest an easy method to control the "packing" of waste in the stitching?

First charge the clean file with chalk or some other powder, even baker's flour will work. Anything to fill the bottoms of the teeth. The brushing clean-out ought to be 10X easier.

I use old-fashioned school stick chalk when working aluminium. All my files cut clean and smooth and none ever get Al shavings packed in them. Same deal rasping any plastics.
Woods and soapstone (steatite) don't seem to pack my rifflers at all.

Cool Robson Valley, thanks for the tip.

Originally Posted by rob streeper

Abdul gives everything a check.


Attachment 330601


Abdul checks my progress.

Attachment 330600

good to see that the boss is on the job

Originally Posted by rob streeper

Isatree,

I'll explain as far as I know.

NaCl is table salt, sodium chloride. Use the rock salt form as there are additives in regular table salt such as iodide, silicates and carbonates. Kosher salt will also do.

CaCl₂ is calcium chloride. You can find it in the form of so-called 'non salt' ice melter, check the label make sure that the non-salt ice melter is not urea or something other than calcium chloride. I get mine from my wife's stash of food grade calcium chloride that she uses for making cheese.

To make the solution you simply use some deionized / distilled / reverse osmosis or similar water (tap will work in a pinch) and put in a couple of handfuls of each salt until it stops dissolving, then add a little more. This solution stores indefinitely and can be used cold or heated depending on the kind of quench you want to do. Hotter makes for less distortion.

Next in the line up the temperature range of quenchants are oils, also used hot or cold. There are special quenching oils but good quality mineral oil works fine for hobby stuff. Be careful with heating it because of burns and fire. Like fried chicken, not fried face.

Next are molten salts. I've been experimenting with these. Various mixtures of sodium nitrite, sodium nitrate and postassium nitrate. Dangerous for those not accustomed to working with hot liquid oxidizers.

Molten metals, such as lead and tin can also be used - careful, very toxic..

Gasses and air can also be used for the appropriate alloys.

Basically everything has it's application. Check with the steel manufacturer for the recommended quenchant and conditions.

Cheers,
Rob

Hi Rob,

I managed to get a small quantity of Aqua Quench 365, it's a polymer based quenchant that you mix with water and you vary the concentration to change the properties, you can mix it up to have the same quenchant properties as oil.

The advantages are it's cleaner and safer ( no fire risk and no smoke ).

http://www.houghtonintl.com/en-us/pr...-Quench-C.aspx

Ray

Hi Rob and Ray. This product may also be of some interest to you both.

Stewie;

http://www.precisionbrand.com/FaqDet...qCategoryid=10

Originally Posted by planemaker

Hi Rob and Ray. This product may also be of some interest to you both.

Stewie;

http://www.precisionbrand.com/FaqDet...qCategoryid=10

Hi Stewie,

I didn't use foil for the floats and rasps because both the Airou and Liogier videos show that the rasps are sand or bead blasted after hardening which is done bare metal to flame. The appear to have a fair amount of scale too. Their furnaces may be set up to be at least somewhat reducing. Perhaps the roughness of the resulting surface after decarburization helps the function of the finished tool.

Rob

Hi Rob. Here's a post on the U.K. hand tool forum that has some relevance to your current work. The guys name is Jim Hendricks.

Stewie;

http://www.ukworkshop.co.uk/forums/p...at-t84424.html

Here's the annealing temp calculator. No way to send it via private message on this site.

Annealing Temperature Calculator 110714a.xls

Hi Rob,

If you are interested in heat treatment, I can recommend the "Heat Treaters Guide Practices and Procedures for Irons and Steels ASM International" It's a bit pricey, but well worth it if you are going to get into heat treating steels.

http://www.asminternational.org/lear...G/PUBLICATION/

Ray