Why don't my dovetails fit?

[Toller]

I bought a HF dovetail jig and 5 router bits for about $20.

The work looks good when it comes out, but they simply don't fit. The male part is 21/32nds at the end, and 12/32nds at the base. The space in the female end is only 18/32nds and 10/32nds; so obviously the male won't fit in the female. (get all your silly jokes out of your system, and then please pay attention again).

The guide is 7/16" OD as specified, the spacing on the template 1/2", and the router bit is 1/2". So; what is wrong?! (My height is perfect; well, at least it would be if I could get them together.)

The first time I tried, the baseplate was a bit off center. But after I fixed that the results were identical. Apparently what I gained on one side I lost on the other, so it didn't matter.

I don't think it is a bad jig because everything is consistant. Is it possible the directions are wrong and it requires a 3/8" guide rather than a

7/16"? That would make the male a 16th" small and should be about right.

Any thoughts would be appreciated.

[Mike in Mystic]

First off, I'm assuming you're cutting half-blind dovetails and using the same dovetail bit for both the pin-board and the tail-board (cut at the same time on these jigs, usually).

Assuming you've set up the jig properly and set the stops in the correct place, etc. the main variable to adjust to get half-blind dovetails to fit properly is the depth of cut. Your setup is producing joints that are too tight, so you need to reduce the depth of cut to loosen the fit. Simply raise your router bit slightly and run some test pieces.

Mike

[Lawrence L'Hote]

I bought the Hartville jig, at about 5 times what you paid HF, and experienced much the same problem(s) you describe in learning how to setup, adjust and use the jig. Practice on scraps and, believe me, with a little patience with yourself you'll be making good dts. Once you get everything setup right take good notes with drawings and store them where you can get them when you want(voice of experience, again). I'd try the different guide you spoke of. If that doesn't work you've eliminated one probably solution. You might check around and see if you can get a Porter-Cable instruction booklet or call Hartville 1-800-345-2396 and ask for a copy of the manual for #12378 12" dovetail jig. Follow the instructions exactly. Larry

[James D Kountz]

What's your stock thickness? For 1/2" stock your bit height should be right at 9/16" give or take a hair for different bit manufactures. I have the Jet jig which is basically the same but I do have the aluminum template not the plastic. Which is yours? Check your bit height.

Jim

[Bob Jones]

Go to woodstock international's web site. Look for their dovetail jig manual. It's excellent. It's also copyrighted. You can read it online (pdf file), or let your conscience be your guide.

[Duke]

The 7/16 template is correct as stated in the manual. Not sure why yours are getting off like that...do you have the bit depth correct and are you routing out the "female" (your term) end thoroughly?...I usually make at least 2 passes.

In any case, I didn't have luck reading the manual that came with my HF jig so I downloaded the Shop Fox manual for identical jig:

more info and troubleshooting in this manual. I have used mine with success on many occaisions, btw.

[Larry C]

I have the same jig, but I've never used it. However, I did find a much better set of instructions for it. The link is at home, but I'm pretty sure it was by Woodtex (sp???) and you can download it from their website.

[Leon]

Like Mike and Lawrence have already indicated, the fit on the typical Half blind dovetail has to be EXACT. The type jig should not matter at all. With blind dovetails the bit has to be set precisely at the correct depth for the joints to fit properly. Thickness of the wood does not matter. Again like previously stated, if the joint is too tight, make a shallower cut. Too loose, make a deeper cut. Minute adjustments will make a lot of difference. Once you have found the sweet spot depth setting record that setting for THAT BIT. You will want to use that depth setting for that bit all the time. If you buy another bit, start at that setting and again search for that sweet spot.

[Toller]

It was that simple; I reduced the depth of cut and they fit perfectly. My manual says to have it protrude 23/32nds; the Woodstock manual says

9/16ths.

[James D Kountz]

I think I said that didnt I? Geez man I wouldnt steer you wrong!! ;-)

Jim

[Mike in Mystic]

Of course you did, but I said it 6 minutes earlier hehe

[Leon]

Yeah well some times you get recognition, sometimes you don't. BTY, stock thickness has no bearing on the correct bit depth. You use the same setting regardless of stock thickness.

[Larry C in Auburn, WA]

WoodSTOCK International. Here is the link to the jig manual:

[JAW]

Pratice and setup, just like others have said. This weekend I made 3 drawers with DT joints and they came out perfect(or nearly as perfect as God would allow me, but to me the looked great). Had to use the rubber mallet for a couple of good taps to set them in place, but otherwise they are fine. Took me about 4 scraps of wood and 45 minutes to set it up though, but that time is insignificant to the longevity of those joints.

Jerry

Toller wrote: