[RobAdkins]

hello all,

im a newbie here and thought i'd ask a silly question. here goes. I'm using the perennial porter cable 4216 dovetail jig and I'm having mixed results. some i can figure out and some i can't. here's one i can't. after cutting a joint in some panels for a project, i realized there was a discrepancy in the offset resulting in uneven edges. I'm very puzzled by this as both prices were snug against the offset guide and were held snug with the clamps. i'd cut previous joints with success using the same methodology so I'm a bit flummoxed. what i CAN tell you is that the panels are 1/16" thinner on one side due to an out-of-whack set of planer knives. could this be the issue? I'm having trouble reconciling how it would be but as it's the only difference, it must be. thoughts? thanks in advance -rob

 

[conifur]

By George, I think you got. I dont understand all your terms, but that thinner piece is not going to match up do to the taper width difference. A pic would help.

 

[JBrow]

RobAdkins,

I have to believe that misaligned edges when the dovetail joint is brought together is because the stock was not firmly against the stops or the stock is at differing widths. I suspect the workpieces are the same width; but if the workpieces align along one edge but not along the other edge, the workpieces are of differing widths. I also assume that the prior dovetail joints successfully routed are of the same type requiring the same jig settings as the one in which problem arose.

I have learned on my Craftsman dovetail jig that the even though the stock seems like it is firmly against the stops, when I look sometimes they are not. Debris from a prior cut can get trapped around the stops, preventing proper contact with the stops. As a result, when I dovetail, I keep the shop vac handy. After I remove stock from the jig, I vacuum things off before making another cut. I also visually check to ensure the vertical and horizontal stock is properly set. I am not familiar with the Porter Cable jig or its stops, so I also have to wonder whether the stops got out of whack.

One idea to troubleshoot the problem if you have not yet done so is to place the misaligned pieces back in the jig as if they had not been routed. If in fact the vertical and/or horizontal pieces were not originally firmly against the respective stops, it should become immediately clear.

The workpieces variation in thickness may affect the joint, but I fail to see how it would affect the alignment of the edges. Establishing alignment of the bottom edges of the workpieces is the job of the stops.

 

[rwe2156]

I have no advice other than tune to your favorite tunes, sharpen up your chisels and do them by hand…...

 

[JohnDon]

If you're cutting through dovetails, using two routers (one for each bit), if one of the guide bushings is off center, you can get an uneven edge.

 

[pintodeluxe]

That jig requires you to use stock width of 4-1/4", 5-1/4", 6-1/4" etc.
If you use any other width besides an even inch plus 1/4", you will not get a neat half pin at each end.

There are enough little issues to iron out with dovetail jigs, and starting with stock that isn't straight and square will only compound those issues.

Also we need a picture or more details to really answer your question. For instance you didn't mention if the uneven edge was on the side (jig depth setting), or uneven top to bottom (consistent stock width, in the correct increments, fully against side stop on jig, cut with router that has centered guide bushing of the correct size etc).

 

[OSU55]

You need to get your planer knives back-in-whack. I have the same jig. The better the stock is prepped, the better the jig performs.