How Do I Dovetail Bolsters?????

Joined
Oct 8, 2003
Messages
2,181
so guys what do i need to dovetail bolsters?? i have KMG and i can adjust the angle on the platen but i need to gte pyroceram so its nice and flat... its too beat up to give a good flat result. any tutorials or suggestions would be appreciated. hmmmmm maybe someone will come to IG's little party and show me how to dovetail bolsters, maybe i could work something out with some meat pie, huh my gray??? :D
speaking of mainers, is lamont coming? i have a few questions for him
thanks in advance
 
I don't have any fancy milling stuff, so here's how I get by...
1. Cut out bolster peices oversized. Don't cut the actual profile, just squares with the right overall dimensions.
2. Drill to fit the pin holes in the tang of the knife. I do this before any shaping so that it doesn't really matter if the holes are a little bit off as long as they match the tang.
3. Now I put pins in the holes to index the 2 peices together and grind them to match the profile of the tang. Be sure to get the rear edges that will meet up to the scales profiled to the angle you want(not the dovetail, the line formed between scales and bolsters)leave a little extra meat there.
4. Using a disc sander, with a work table set at the angle I want, I grind the bevel for the dovetail. Do this very slowly, grind and check, grind and check, until you bevel just barely goes all the way across the thickness of the bolster. If you do it right, the bolsters will still match up, since you had them profiled the same.
This isn't overly difficult, but you really have to concentrate to get the bevel ground without changing the line the back of the bolster follows. Because of this, I go for a pretty simple junction between bolters and scales. No long sloping lines or anything.
5. Get some 400 grit or so wet dry paper, and a good sanding block
(I use a piece of precision ground steel) and lap the beveled edge of the bolster nice and smooth. Don't overdo it, no one will see it. You just want to get rid of any deep grind lines, and take off any burr that might have formed.
6. Pin them on.
Now for the scales.
1. Cut out a block oversized.
2. Grind a bevel on the end, using the disc sander set at the same angle as the when you did the bolster.
3. Lap bevel to insure that its flat
4. Push the scale firmly into place against the bolster and clamp it there. Now drill a pin hole, and put a pin in, drill the next hole etc.
5. Repeat for the other scale.
6. Shape handle, and do handle work as normal.

Hope that at least gives you some ideas on how to go about it :)
 
Set your KMG platen on a 30 degree angle using a magnetic degree angle level
available at Harbor Freight for around $5.00.
Grind bolsters, flat against the platen using your bench rest, and also your handles after the bolsters at the same time to ensure perfect fit.
Take your time to make sure you are grinding left to left/matching correct ends, bolster to handle etc.
You will come out with a perfect matching pair as long as you do not move the platen once it is adjusted until all are ground and finished.
I spray blue layout on my bolster end and when it is all ground off, I know that it has been ground to 30 degrees over the complete end surface.
Once you do it,it is a breeze.
Good Luck,
Jon
 
thanks a lot guys..... i'm dying to get out in the shop and try that now. i'll keep you informed and send some pics when i'm done. :D
 
Something I picked up from Chris Crawford's auto video was to grind one part of the matching pair right side up and the other upside down. That way they will match, no matter what.
 
I do mine almost exactly like Matt does. Keep the grinder table set at the same angle through the entire operation (that is do the bevel on the bolsters and the scales at the same time before any other operations with that grinder unless you think you set up is accurate enough to duplicate the angle setting). Make sure to orient the scales properly before you grind the bevel on the end of them! :rolleyes:
 
alright well now i remember the KMGis only set-up to do 45 degree angles.
is there any specific angle makers prefer to use for any specific reason??
thanks again
 
Won't help you much if you don't have a mill, but this is way do it. First I make sure both the bolster material and the handle material are dead flat. Then I lock them down on a 5x7 tilt table, set at about 30 degrees on my mill with just enough of their edges sitting off of the table for clearance for the end mill. A few passes across those edges gives me a perfect match. Remember to orient the handle material correctly after you've chosen the "out" side. Pat McGroder
 
Back
Top