

Although you could make bolsters entirely with hand tools, files, hacksaw and so on, a drill press would be considered an asset when making the pin holes. Start with the most powerful tool in your shop, the permanent marker.
The left and right pieces must mirror each other to preserve symmetry. I normally sketch the bolster out on the knife and determine how it will look and where the pin holes will go.
Lay the left and right pieces out on the material you wish to use as a bolster.
Be sure to leave enough space between the pieces for your hacksaw or band saw blade to get through when you separate L & R later on.
I like to do the bulk of the removal while everything is still on the bar. Then cut the pieces out once you get close to the lines.
Clamp the two pieces together with vise-grips and shape them as a single piece. Pay careful attention to the fronts.
Now drill the holes in the tang. Typically I drill two #30 holes for pinning the bolster with 1/8" pins. Keep the holes at least 3/16" away from the edges so we can round the bolster and not be taking too much pin off.

With the left bolster piece positioned exactly where you want it, clamp with vise-grips and drill the pin holes.
Drilling the first bolster piece while clamped on with vise-grips.
If you want to make a block like I use for the drill press see my page on Drill Press Block #3 for instructions.
Here I like to put a temporary pin to hold the L bolster piece to the tang. Insert it into one of the holes. When the L and R pieces are perfectly lined up, clamp with vise-grips and remove the temporary pin. Drill through the L piece, and tang all the way through the R piece.
Unclamp the pieces and finish the fronts.
After drilling (if your drill press is nice and square) you can put some temporary pins and finish the fronts. I use plain old 1/8" rod from Home Depot.
Remember that the bolster fronts will be nearly impossible to finish once pinned to the knife.
Finishing means, shaping, sanding and buffing. Here are the two pieces after some work on the buffing wheel.
Although there are no rules about what pins to use, generally the same material is used for pinning. E.g. brass pins on brass bolster pieces. There is nothing to say that you cannot use pins to contrast or use mosaic pins.

Banished list:
No flecks, filings, dirt, fibers or hair is allowed between the metal pieces...period. Brush, blow, clean 100%.
Cleaning detail:
You will want to scuff the interior surfaces with coarse sand paper, (I use 60 grit) and clean all surfaces with acetone or high-test rubbing alcohol.
Sealing detail:
This is where I like to use a small amount of Acraglas to seal the bolster pieces to the tang. This prevents moisture migration and ensures the joint is easy to keep clean. Be careful not to use too much epoxy. Also be careful not to allow the epoxy up into the pin holes. Epoxy in the holes can appear as a ring around the pin when finished.
Ready, Set...Press!


After the big squeeze, work the bolster pieces with the belt grinder and the pins should disappear. Here I used a 60 grit belt, but the 120 looks even better.
Shaping the bolster from here is academic. I use the files, small wheels, drums on the drill press or whatever is needed to shape and clean up.
Be careful about heat. Too much grinding will burn the Acraglas. If you are using regular 50/50 epoxy you'll smell it burning and it's not pretty.
Well there you have it. One way to attach a front bolster. Again, not the only way to do it, but one that I can say that produces great results. Please let me know if you have tried this and if you have any suggestions on how to improve the process.
D
6 comments:
Do you think that a vise could be used in place of the hydraulic press?
I have experimented with using a 5" mechanic's vise and yes it can be done. It's a little fiddly to get the washers or spacers to stay put as the jaws are vertical. If your vise is able to move to the horizontal position it will be easier. Sufficient force is available with a larger vise.
Dan
Again? Whether I'm building a heat treatment oven or researching whether to build or buy a belt grinder, when I search around you always seem to have the answer.... You're awesome. Thank you for being such a help to your fellow knifemakers
Thank you for your kind words.
I love doing this.
[Very nice tutorial, as always!] Another method that seemed quite intimidating but worked PERFECTLY the first time I (nervously) tried it, is to silver-solder. This worked especially well with the brass I was using, as the solder makes the seam between the steel and brass *completely* invisible, as though the metals were a single piece that just changes color suddenly. The trick I figured out is to pre-"tin" both bolsters with a thin even layer of silver solder (don't forget clean clean surfaces and flux!). Then I put a couple of brass pins through and bent the ends to hold it all together, and heated it up with a torch. The solder flowed like water - no gaps whatsoever. Other protips: wrap the (hardened) blade in a wet rag just as a precaution against overtempering, and rub a welder's soapstone stick/pencil on the front of the bolsters and blade in front of them to keep solder from sticking there and giving you a near-impossible filing job. (Some folks use yellow ochre powder + water - art supply stores carry it.) When done, straighten the pins and peen 'em in. Nice thing - if it goes badly, you can always melt the bolsters off and try again. FYI, I used Stay-Brite and Stay Clean solder & flux. Melt temp about 450°F/230°C. I got most of the info from a YouTube 4-vid series - look up BoseKnives Soldering Bolsters - and added a few twists from other sources.
I use two small boards one on each side with holes count out corresponding to the pin placement and then I put it in the vice and squeeze the two halves together!
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