Tip 'O the Month,for Drawer Bottom Dadoes

[Lawrence L'Hote]

If you don't make drawers then stop right here and look at the next person's post.

Presently, I am in the drawer building mode. It seems no matter how careful I am with cutting the drawer parts, when I assemble the drawers after cutting the dovetails(using jig) the sides don't match up with the front. If I use the top side of the drawer parts as reference, when I cut the dadoes for the bottom, the dadoes on the sides sometimes don't match up with the front dado. The problem is worsened if you need to do rabbeted, half blind dadoes. If you like your drawer bottoms snug, and the dadoes don't match you're in doodo. In the past, my quick fix is just to plane(or chisel) a little or widen the dado which results in lots of slop in the fit. I tried something else that seems to work ....I use hot glue to make up the slight difference in the reference surfaces(some rasping may be required) and then cut the dado. Maybe this pictures will help.

[Greywolf]

How about cutting the dadoes after making the dovetails? That seems to work fine.

Pat

[Leon]

If I don't pay too close of attention and let my router rotate while cutting the DT's, the sides will be off set from the front and back. The guide bushing not being perfectly centered is the culprit. If you let the router rotate when cutting between the jig fingers, the cut may be too far left or right. The result is that the sides do not match the front or back like you describe. If this happens, I trim the top or bottom edges for a good fit. Then after I am satisfied with the drawer fit in the corners I cut the dados for the drawer bottom.

[Swingman]

If I understand you correctly ... If you cut the drawer bottom grooves last, referencing the same edge of each piece, after first verifying the fit of the dovetails, you won't have this problem.

The trick is initially setting up the DT jig so that the proposed groove location is hidden by the dovetail joint when the piece is assembled, particularly when using half-blind dovetails.

[Lawrence L'Hote]

Well..that's what I do. Still about a sixteenth(sometimes more) inch error seems to creep up on me.

Larry

[Lawrence L'Hote]

Well..that's what I do. Still about a sixteenth(sometimes more) inch error seems to creep up on me.

Larry

[Lawrence L'Hote]

Well..that's what I do. Still about a sixteenth(sometimes more) inch error seems to creep up on me.

Larry

[Lawrence L'Hote]

Well..that's what I do. Still about a sixteenth(sometimes more) inch error seems to creep up on me.

Larry

[Lawrence L'Hote]

Well..that's what I do. Still about a sixteenth(sometimes more) inch error seems to creep up on me.

Larry

[Jack]

Mouse stuck on the send button? or frustration with the comments???

[Lawrence L'Hote]

If you don't make drawers then stop right here and look at the next person's post.

Presently, I am in the drawer building mode. It seems no matter how careful I am with cutting the drawer parts, when I assemble the drawers after cutting the dovetails(using jig) the sides don't match up with the front. If I use the top side of the drawer parts as reference, when I cut the dadoes for the bottom, the dadoes on the sides sometimes don't match up with the front dado. The problem is worsened if you need to do rabbeted, half blind dadoes. If you like your drawer bottoms snug, and the dadoes don't match you're in doodo. In the past, my quick fix is just to plane(or chisel) a little or widen the dado which results in lots of slop in the fit. I tried something else that seems to work ....I use hot glue to make up the slight difference in the reference surfaces(some rasping may be required) and then cut the dado. Maybe this pictures will help.

[Lawrence L'Hote]

Well..that's what I do. Still about a sixteenth(sometimes more) inch error seems to creep up on me.

Larry

[Lawrence L'Hote]

Thanks Leon. I didn't check the centering of the bushing. I use a Pat Warner Lexan base just for DT's and never remove the bushing. One more thing to add to my notes of to-dos. It's curious the jig manual(Hart Design

12") goes into detail on adjusting this and adusting that but makes NO mention of the problem of an off-center bit although, clearly, it can be a problem. I like using a stacked dado and my table saw. I feel more comfortable with the saw and it's easier(for me) to compensate for the rabbet offset with a 3/8 " thick key I use.

Larry

[Lawrence L'Hote]

Thanks Leon. I didn't check the centering of the bushing. I use a Pat Warner Lexan base just for DT's and never remove the bushing. One more thing to add to my notes of to-dos. It's curious the jig manual(Hart Design

12") goes into detail on adjusting this and adusting that but makes NO mention of the problem of an off-center bit although, clearly, it can be a problem. I like using a stacked dado and my table saw. I feel more comfortable with the saw and it's easier(for me) to compensate for the rabbet offset with a 3/8 " thick key I use.

Larry

[Lawrence L'Hote]

Well..that's what I do. Still about a sixteenth(sometimes more) inch error seems to creep up on me.

Larry

[Leon]

I cut the dado's with the TS also except I use my Regular kerf blade. I make the first pass through all the pieces plus a scrap, move the fence and test cut the scrap and check the fit to the plywood bottom. If the fit is snug, I finish all the other pieces at that fence setting. Because most

1/4" plywood is thinner than most of the 2 outside dado blades I get the snug fit with one blade.

[Leon]

I think the problem is that his sides and fronts do not align properly at the corners. One is higher than the other when test fitted. If this is in fact the problem, the bottoms dados will not align correctly regardless of when they are cut. The tops and bottoms of all pieces need to be the same height in the corners for the dados to align correctly also.

[Leon]

Oups... Nevermind. I see you were talking about cleaning out the rabbet on the TS rather than with the DT bit.

[Groggy]

Leon,

Although it doesn't applly to using template guide bushings, there is a trick that can be used to centre the bit to all external points.

Put a reference bit in the router and lower the point so the router cannot move off the point. Then slowly move the router edge to a belt sander or disk and rotate the router until the belt has even contact at all points.

The technique is not dissimilar to cutting a circle on a BS.

Greg

[Leon]

Yeah that will work.. Thanks Greg. Fortunately I use a Bosch 1617evs on my Leigh jig. The base is adjustable so that it can be centered to the bit and remain that way. I use a centering tool to center the bushing to the collet and tighten down the 4 pan head screws to lock the base in that position.

Then on top of that, I try to keep the router "cloocked" in the same position through out the process of cutting the DT's just in case.