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Old 27-04-2010, 05:34 PM
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Cybertrix Cybertrix is offline
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Join Date: Dec 2009
Location: Nottinghamshire
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Default Fitting Bolsters To A Full Tang Knife

After my last knife someone asked about how I do my bolsters so here is part one.

I am making a stalking knife that will have brass bolsters so this is how i do them.

Having made the knife to the point of it being hardened and tempered I will make the bolsters before I finish the polish on the blade. I drilled the holes for the pins when I was making the knife so make sure you decide which size pins and materials you are going to use before you do the HT.

I will be using 4mm brass pins and 6mm brass sheet, I have found that for my size knives the 6mm brass is ample.

Clamp the knife to the brass on the drilling machine so you can drill the first pin hole. Give yourself planty of room, 3 or 4mm bigger than the bolster will be, in case the blade moves a little while you are drilling. Make sure the drill bit is sharp and you have the right drilling speed.

This piece of Brass was cut on a guillotine so the edges have rounded corners and may not be very flat. Before I drill the holes I flattened the underside by rubbing it on some corse wet and dry taped to a flat surface. If your material has been cut by saw this step may not be needed but check.

After you have deburred the hole, take a piece of pin stock and put it in the hole and the knife so it holds the two holes in position. Clamp the knife again and drill the second hole. If there is a third hole do the same again so you keep all the holes lined up.

Use the pins to locate the blade while you scribe the profile of the knife onto the brass.

Scribe both top and bottom outlines.

Decide how big you want the bolsters to be and what shape the will be, mark them out on the blade with a marker so you can get an idea of what you want before you cut them out.

Now using these marks, transfer them to the brass so you can scribe them before cutting them out.

Use a can or other object of the required shape to get a good line.

Now you have the bolster marked out on the brass with the holes in the right place.

Using a hacksaw cut the bolster out and refine the shape a little with files. Be carefull not to cut too much off or you might have to start again.

After you have refined the shape, deburr the edges and make sure the face of the bolster that sits against the knife is flat. I use the wet and dry taped to a flat surface method again.

Now make your second bolster in the same way as the first.

Put the pins in place to line up both bolsters and clamp the in a vice. We don't need to worry about the top and bottom edges just yet but we have to make sure the riccaso edge and the handle edge are filed level and polished smooth.

The polish need not be to the final finish as there is still more work to do just yet, I go to 400 grit.

The edge that mates with the handle material MUST be flat and square, unless you are doing dovetailed bolsters of course.

Now I try them for fit before I give the blade its final finish, after which I will tape up the blade to protect it before we anneal the pins and fit the bolsters permanently.

After I have polished the blade I will take some more pictures of the last stages.

Last edited by Cybertrix; 28-04-2010 at 02:58 PM.
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