Dovetail file?

[Mauser06]

I have a number of different triangle files and have used them all for trying to cut dovetails.

Long story short, I'm not really happy with them. They don't seem to cut enough of an angle if that makes sense. 

I've also tried the TOTW chisel for raising dovetails with little success...



Any advice? 

[Jerry]

Mauser06, I use a tri cornered file for my dovetails with one edge ground safe. I may be doing it somewhat different though. First, I measure the top from angle to angle lengthwise. I layout where I want the dovetail to be, then use a  hacksaw with a fine blade and cut a series of cuts. I then use a flat engraving chisel to remove the webs. Then, all I have to file is the bottom of the dovetail flat and the dovetail angles for a tap in fit. Hope this helps. Jerry

[Stoner creek]

Practice.
Also, take one of your 3 corner files and grind all of the file off one surface making it a safe edge that won’t dig where it doesn’t need to. After I get my depth I put the 3 corner file with the safe edge to work. I hate dovetails but I don’t have a milling machine so I do it the old time way. I normally reward myself with something cold and tasty when I’m through with the dovetails.

[Turtle]

I have a special 3 corner file dovetail  made with one cutting edge. It has no taper--parallel sides. Works much better than regular 3 corner files. I think I got it from brownells.

[Bob Roller]

Over the last 50 or more years I have made several sizes of dovetail files out of
common triangular files and like has been mentioned,the FLAT grinding of one side
will usually give you what is needed.I have a milling machine and for a 3/8"dovetail
I mill a 7/32 slot the depth needed across the barrel and then change to a 3/8x45
degree cutter.To do it with files,I used a square file CAREFULLY and the when the
needed depth is reached it is cut and try with the modified triangular file until a
tight fit is obtained.Getting in a hurry is guaranteed failure and in this job,accuracy
IS final.

Bob Roller

[Scota4570]

 "...and then change to a 3/8x45 degree cutter."

I thought 60* was the standard for dovetails.  Why use 45*?

[Bob Roller]

Apparently I was thinking of one thing and typing something else.
It's flatulence of the brain and it ain't getting any better.

Bob Roller

[smallpatch]

As mentioned above, the dovetail file from Brownells.  Pricey, but well worth the price!

[Stophel]

If you get the dovetail file, do yourself a favor, and grind down the corner opposite the cutting face a little bit.  That sucker is SHARP, and will slice your thumb wide open!

[Mauser06]

Thanks all.  I appreciate the info! 


I've tried various triangle files.    Even tiny ones.  Seems they just aren't pointed enough to make a dovetail like we want.  Maybe that's the secret is grinding the safe side a little extra to get a nice sharp corner?    I ground d the teeth off one but just took em off enough so they don't cut. 


I will try to shave it down a little more and see if it helps. 


If not, the Brownells one is a bit expensive...but, I cut around 6 dovetails on each build...not opposed to paying for quality tools if they make the work better. 


I do mark it out and use a hacksaw then file the flat area before cutting in the corners.   


A scrape barrel piece would be nice to have.

[smallpatch]

By the one from Brownells, it's worth the money.

[Mauser06]

Well....I trust your word. Small investment for a good tool and used enough and on important tasks I don't have an issue buying one. 

[Davemuzz]

Practice.
Also, take one of your 3 corner files and grind all of the file off one surface making it a safe edge that won’t dig where it doesn’t need to. After I get my depth I put the 3 corner file with the safe edge to work. I hate dovetails but I don’t have a milling machine so I do it the old time way. I normally reward myself with something cold and tasty when I’m through with the dovetails.

^^^^----^^^^-What he said. I took one of my 3 corner files and ground a "safe" side. Cutting dovetails for sights now are like falling off a log!!

[moleeyes36]

By the one from Brownells, it's worth the money.

I'll second Dane on that; it's a great tool.

Mole Eyes

[Bill Raby]

I have a milling machine, but I cut dovetails by hand. It is quicker and easier to do by hand than it is to get everything set up in the mill.

[Mike Brooks]

Maybe that's the secret is grinding the safe side a little extra to get a nice sharp corner?

BINGO!

[Elnathan]

Maybe that's the secret is grinding the safe side a little extra to get a nice sharp corner?

BINGO!

I believe that most of not all of the triangular files sold in hardware stores are taper files of one sort or another, i.e., the design was originally intended for sharpening hand saws. They aren't made well enough to terribly useful for that these days, but they still have the radius at the corner to keep them from filing a sharp corner in the gullet of the saw teeth. The radius helps prevent cracks forming.

True triangular files are sometimes called three-square, and should have sharper corners, but I don't know how much sharper, having never seen one. My dovetail file is just a hardware store Nicholson taper file with enough of one side ground away to form a very sharp corner.

[Daryl]

Practice.
Also, take one of your 3 corner files and grind all of the file off one surface making it a safe edge that won’t dig where it doesn’t need to. After I get my depth I put the 3 corner file with the safe edge to work. I hate dovetails but I don’t have a milling machine so I do it the old time way. I normally reward myself with something cold and tasty when I’m through with the dovetails.

^^^^----^^^^-What he said. I took one of my 3 corner files and ground a "safe" side. Cutting dovetails for sights now are like falling off a log!!

It's a LOT easier if Taylor does it. Perfect dovetails are the result.  If I do it, not so good and yet my dovetails files are super- short corners, etc, as they just be.