HF dovetail jig question

[AlanWS]

I got the HF dovetail jig with the recent coupon last weekend. Using the woodstock manual found here (and elsewhere) http://www.woodstockint.com/images/manuals/D2796_m.pdf it is working reasonably well.

I used the woodstock manual for instructions, but a 1/2" bushing with the 1/2" template, not the 7/16" specified by the woodstock instructions. I offset the stops for the two pieces by a full 1/2" as well. Waxing the template also helped cut more smoothly.

My question is this: the template moves as it clamps down on the stock. A little sideways motion is not a problem, as the joints fit but the pins and tails may not be perfectly centered up and down on a drawer joint. But template movement in and out on the jig causes the fit to change from flush to too deep or too shallow, or even deep on one side and shallow on the other.

This can be avoided by measuring the offset of the fingers from the edge of the stock, but the point of a jig is to prevent the need to do this. I've considered a block with a 1/8" rabbet to hold against the stock and fingers as I clamp down the top clamp, or perhaps pins to hold the alignment of the rear clamp piece.

How have any who use this jig dealt with it? Is there a very simple fix? Am I just doing something stupid?

[BrazosJake]

I'm not even going to read the question, there are two answers:

DON'T BUY IT!!!

If you already did, the other answer is:

TAKE IT BACK!!!

[AlanWS]

As I wait for those who use the jig to check in, I might as well add a bit of detail for anyone considering using it. I figured for $20 it was worth it even if I just used the template to make my own jig. But I think I can make this one work with small modifications.

Using the woodstock directions, it's not too hard to set up. I've never used a dovetail jig before, though I have handcut dovetails, so I know what I'm trying to do. Last evening I set it up, milled some stock, cut several test joints, and then made and glued up two small drawers. The problem I mentioned above is the main trouble.

The other limitation is that with the suggested setup of 1/2" bushing, 1/2" diameter 14 degree 1/4" shank dovetail bit set to protrude 1/2" below the router base, the joints fit but are very shallow -- about 1/4". This AM trig told me that if I switch to the 7/16" bushing and set the bit 3/4" below the router base I'll get more reasonable 1/2" deep dovetails that should still fit.

[LCHIEN]

As I wait for those who use the jig to check in, I might as well add a bit of detail for anyone considering using it. I figured for $20 it was worth it even if I just used the template to make my own jig. But I think I can make this one work with small modifications.

Using the woodstock directions, it's not too hard to set up. I've never used a dovetail jig before, though I have handcut dovetails, so I know what I'm trying to do. Last evening I set it up, milled some stock, cut several test joints, and then made and glued up two small drawers. The problem I mentioned above is the main trouble.

The other limitation is that with the suggested setup of 1/2" bushing, 1/2" diameter 14 degree 1/4" shank dovetail bit set to protrude 1/2" below the router base, the joints fit but are very shallow -- about 1/4". This AM trig told me that if I switch to the 7/16" bushing and set the bit 3/4" below the router base I'll get more reasonable 1/2" deep dovetails that should still fit.

I think the dovetail jig I have has 7/16" wide slots between the fingers and you are supposed to use a 7/16" bushing. I thought they were all like that.

[messmaker]

I think Loring is right. Imagine that.

[newood2]

“the template moves as it clamps down on the stock”.

The template should have no play once the wood is clamped down. Make sure the “clamping pressure knobs’ are adjusted properly, the “template knobs and the 4 template screws are tightened good. If you still have play then it’s defective,you should not have to modify anything.

“The other limitation is that with the suggested setup of 1/2" bushing, 1/2" diameter 14 degree 1/4" shank dovetail bit set to protrude 1/2" below the router base, the joints fit but are very shallow -- about 1/4"

If it’s a ½” template, a ½” 14deg bit should work fine.
The guide bushing should protrude 1/8” to 3/16” below the base of the router and have a 7/16” outside diameter.
The tip of the bit to the router base should about 9/16”.



The template with a ½” wide slot should use a 7/16” OD bushing.
This setup works fine for me with PC690.

Howie

[Lee4847]

( embarrised to admit) I know Loring is right... it takes a 7/17 bushing...been there with the shallow cuts. Took me days and made a lot of scrap to figure it out!

PS. I agree 100% with BrazosJake !!

[mikeinkcmo]

I agree with newood2 with regard to setup. This style jig is a bugger to set up for good tight joints and many people have one router setup just for the DT jig. Myself included.

The HF jig is just about as good as any of the others so IF you decide to get ur money back DON'T expect much better from the high priced offerings.

[drumpriest]

Dovetail jigs are funny things. The cheaper they are, the harder they are to use, leading to frustration. This sounds somewhat generalized, but I've tried most of the ones on the market. Honestly, thus far I'd recommend the PC jigs, or the Leigh jigs, if you have the cash. Or just hand cut them, which is less frustrating than a cheap dovetail jig.

Consider this also, if you are going to have a router just for this jig, you could have forgone the extra router, and gotten an easier to use jig. Just food for thought.

[BrazosJake]

It's 1/2" between the fingers and takes a 7/16" bushing.

Once you get DTs that fit, either lock it in and dedicate that router to DTs (and never touch the depth), or make a setup block muy pronto.

[JimD]

The template guide that comes with the HF dovetail jig - which works well for me - are set at 1/2 inch intervals to make drawers at 1 inch intervals. I bought a separate guide from Grizzley that fits pretty well that has dovetails at 7/16 intervals for drawers that vary by 7/8 inch. You do not absolutely have to have the drawer vary at the interval of the template but if you do not, you will end up with a partial dovetail somewhere. That is not terrible if you put it on the bottom or something but then you have to set the stops on both sides of the jig which I consider a pain. I never put the stops in from the edges very far - I do not understand why the otherwise good woodstock instructions say to do this. I set the side stops out about as far as they will go. On real narrow pieces this can make it hard to clamp but you can put a scrap in or something. On dovetail jigs like the PC (which is nicer than the HF but a lot more money), you have no choice, they are out at the edge of the travel - so it can clearly be done this way.

For both template guides, you use a bushing on your router that is 7/16 diameter. In the template guide that comes with the HF, you have to go a little sideways at the bottom of each finger. I have never used anything but a 7/16 guide on the router so I cannot really say what happens with a 1/2 inch but it would prevent using the 7/16 finger guide from Grizzly that I like so I will probably never attempt it (I have a 1/2 guide bushing but see no reason to deviate from the instructions in this case).

I agree with BrazoJake on a depth block. You can just cut into a piece of scrap but what I did was make a little C shaped piece of scrap with the open part about 1/2 inch taller than the bit projection - an inch or a little more. Then put a fine thread drywall screw into the open part of the C and adjust the screw until it just touches a correctly set bit. Almost takes longer to type this than to make the jig. Now put is somewhere you can find it.

If you search for my posts, you can see some pictures of the simple stand I made for my HF jig of baltic birch plywood. It lifts the jig about 6 inches which helps my back. I put lines on the jig for where the extended side stops go. Makes setup pretty simple. It has a drawer for wrenches and setup jigs (the drawer was dovetailed on all four corners with the HF jig, of course).

With respect to things moving when you clamp down, I would check where the screw heads are. I've noticed that HF used hardware store fasteners which sometimes interfere with each other. You might have to reduce the thickness of a carriage bolt or two a little with a file. Also understand that the clamps do not have to be super tight. There is not a lot of force trying to move the pieces.

You need to cut the pieces correctly to get good joints - if you do not cut the front, back, or sides square, you will not get a good drawer (but with my setup, I see that when I put the wood into the dovetail jig and can start to figure out what I will do about it before cutting the joint). If you cut things square and put the jig on a little stand, machine cut dovetails are very quick and easy to do - and add some class. They should fit snugly enough you have to tap the joint together and do not need clamps to hold it while it dries (but check the diagonals and make sure the drawer is square).

Jim