In earlier posts I discussed the use of slips as a technique to reinforce thin drawer sides. But slips can also be used to enhance the appearance of drawer bottoms in fine furniture. After reading my latest post on slips, a reader wrote to ask “…how do you maintain perfect alignment during the glue-up”? This is a great question, and one I did not address earlier. I will use photos to illustrate.
I make the slips with a groove that accepts the tongue machined on the sides of the drawer bottom. The front edge of the drawer bottom, in turn, also has a tongue, and is housed in a groove in the drawer front. And since the slips will be glued to the sides, it is imperative to that the groove in the slips be in perfect alignment with the groove in the drawer front.
Tongue & groove joinery is great for this purpose. I do the entire process with the drawer upside down, but not yet glued. The key to proper alignment is to use a small piece of waste, and cut a tongue on one side and one end. I then insert the tongue on this piece into the groove in the slip – remember, we are looking at the bottom of the slip in this photo:
This piece can now hold the slip perfectly aligned with the groove in the bottom of the drawer front:
I then bring everything into place, with the slip clamped to the side, and registered against the drawer front:
Voilá – perfect alignment. Note that I also machined tongues on the two additional small blocks, to allow me to use clamps while reducing the risk of damaging the groove on the slip:
The outside surface also requires a small block, to distribute the pressure and to reduce the risk of compressing the wood too much:
That does it – perfectly aligned drawer slips!
— Al Navas

Good post Al. It is posts like this that motivate me to hone my craft.
Jeff,
Glad you liked it – I am always happy to learn someone may be able use a tip like this one at some point in their woodworking journey!
— Al Navas