Grooving or rabbeting for box bottoms

[James Brown]

When grooving or rabbeting drawer or box sides for the bottom, what's your preferred method for avoiding blowing out the end grain of the pins (box joints or dovetails)?

I usually use a straight bit on the router table for these cuts, with stop cuts where the pins are. There's usually some paring with a chisel afterwards. But those pins are fragile, and at some point I'm looking around on the floor for a little piece of lost endgrain to glue back in. So how do you do it?

Jim

[Charlie Hinton]

The same way you do it.
I try to only go 1/3 of the pin / finger length.

[Andrew Hughes]

In between the pins and stop on the tail.

[Derek Cohen]

When grooving or rabbeting drawer or box sides for the bottom, what's your preferred method for avoiding blowing out the end grain of the pins (box joints or dovetails)?

I usually use a straight bit on the router table for these cuts, with stop cuts where the pins are. There's usually some paring with a chisel afterwards. But those pins are fragile, and at some point I'm looking around on the floor for a little piece of lost endgrain to glue back in. So how do you do it?

Jim

Jim, here is a pin board with the pins sawn but the waste is nit excavated. You will see the groove for the drawer bottom is in the socket ...



Here is the same drawer front with the waste removed ...



The alternate approach is to use slips in place of a groove. The slip is grooved and glued to the sides ...





The drawer bottom is slid in, so ...



Regards from Perth

Derek

[Charles Lent]

I use the small diameter slotting bits from Lee Valley. I dry assemble the box sides and then just run them around the bit in my router table to slot all four sides. The small diameter of these bits cuts all the way into the box corners, leaving a radius slot inside the box corners. I then slightly round the corners of the box bottom before installing it. It's fast, easy, and the slot doesn't show on the outside of the box.

http://www.leevalley.com/US/wood/pag...?p=47818&cat=1

Charley

[Stan Calow]

I like Derek's solution, but I am too lazy to attempt it. I've done this three ways. One is to rout stopped grooves by dropping the properly restrained and stopped piece onto the spinning router bit (saw that in Woodsmith). My variation was to drill pilot holes where I want the groove to stop, and then run it over the router bit from hole to hole, stopping when I hear it has gotten to the hole. Thirdly (mostly for boxes and trays not drawers) was to just glue/screw in cleats on all four sides and attach the bottom onto the cleats. But then I'm just a hobbyist, so sometimes easy wins over elegant.

[Mike Henderson]

Several ways to address this issue. One is to make your dovetails or finger joints so that the groove is covered, as Derek suggested. Another is to use miter joints on the corners. I usually use mitered corners and put a small (FF) biscuit in as a spline for strength. That shows off the flow of the grain without the interruption of visible joinery. Here's an example:
OliveWoodBox004.jpg

A third is to do your joinery (dovetail or finger joints) first and then do a dry assembly of the box. Use tape to hold it together if necessary. Then adjust your slot cutter bit on your router table to the proper height and place the box over the slot cutter bit, so that you're cutting the slot on the inside of the box.

This will leave guarantee that your slot lines up at each corner. If you cut the slot first and then do your joinery, you risk having the slots misaligned.

But this technique gives you rounded corners where the slots come together. You can use a chisel to square the corners, or simply round off the corners of your bottom. Or do a combination - just roughly clean out the corners but trim the corners of your bottom a bit to fit.

Mike

[Edwin Santos]

I use the small diameter slotting bits from Lee Valley. I dry assemble the box sides and then just run them around the bit in my router table to slot all four sides. The small diameter of these bits cuts all the way into the box corners, leaving a radius slot inside the box corners. I then slightly round the corners of the box bottom before installing it. It's fast, easy, and the slot doesn't show on the outside of the box.

http://www.leevalley.com/US/wood/pag...?p=47818&cat=1

Charley

+1 on this. Very clever solution from Lee Valley. Guaranteed to line up perfectly even if your box needs minor adjustment to the top or bottom.

[Gary Ragatz]

I use the small diameter slotting bits from Lee Valley. I dry assemble the box sides and then just run them around the bit in my router table to slot all four sides. The small diameter of these bits cuts all the way into the box corners, leaving a radius slot inside the box corners. I then slightly round the corners of the box bottom before installing it. It's fast, easy, and the slot doesn't show on the outside of the box.

http://www.leevalley.com/US/wood/pag...?p=47818&cat=1

Charley

Charley - Thanks for the tip - another item for my wish list!

[David Powell]

I found Lee Valley's slotting bits a little over a year ago; now use them exclusively for drawer and box bottoms.

[James Brown]

Thanks to all for their responses.

Derek, thanks for taking the time to post the photos ... with dovetails I've had good luck lining the grooves up with the tails, especially on drawers. I hadn't seen the slips concept before and hope I remember it the next time I need it.

Stan, the pilot hole trick should work for a lot of what I'm doing, which is 1/4" finger box joints on small boxes (see below). I think it will help a lot.

Mike, I like the look of your mitered boxes, especially with the wraparound grain.

To all who recommend the Lee Valley bits, thanks ... I'll check them out.

IMG_0619.jpg

[glenn bradley]

Another user of the LV bits. I use several methods depending on the construction but, the LV bits are used easily 50% of the time.

[James Brown]

Without going to too much trouble, can someone tell me the actual radius of these Lee Valley bits? I have some slot cutting bits that I think are too big for small boxes, regardless of the cutting depth achievable with bearings. Not seeing that info on the LV page. Thanks!

Jim

[Mike Henderson]

Thanks to all for their responses.

Derek, thanks for taking the time to post the photos ... with dovetails I've had good luck lining the grooves up with the tails, especially on drawers. I hadn't seen the slips concept before and hope I remember it the next time I need it.

Stan, the pilot hole trick should work for a lot of what I'm doing, which is 1/4" finger box joints on small boxes (see below). I think it will help a lot.

Mike, I like the look of your mitered boxes, especially with the wraparound grain.

To all who recommend the Lee Valley bits, thanks ... I'll check them out.

IMG_0619.jpg

If you do mitered corners, you can cut the groove on your table saw. If using 1/2" material, raise your blade about 1/4" and cut your groove about 1/4" from the bottom of the box. If your panel material is wider than 1/8" - I usually use 3/16" - move your fence and put the wood through again. Use a piece of scrap to set the distance. That is, cut the first groove in some scrap as well as your sides. Then use the scrap to sneak up on the thickness of your panel (cut, trial fit, adjust fence, etc.). Then cut your sides.

You never have to worry about your groove showing.

Also, use your table saw and miter gauge to cut the miters. To set the gauge, use some properly prepared stock and make a miter cut. Then check that it's cut square across with a combination square. Most accurate way I've found to cut miters for boxes.

Mike

[Charles Lent]

Without going to too much trouble, can someone tell me the actual radius of these Lee Valley bits? I have some slot cutting bits that I think are too big for small boxes, regardless of the cutting depth achievable with bearings. Not seeing that info on the LV page. Thanks!

Jim

I'm not near my shop, so I can't measure the LV bits, but if you try cutting the slot with one of the larger diameter slotting bits, the bearing on the bit will hit the corner before the bit has cut the slot fully into the corner. Your rounded box bottom will need a large radius corner, and there will be a gap left in your box corner where there is no bottom. The smaller diameter bit (and bearing) lets you cut the slot fully into the corner so the corner of the bottom panel can fit into it and leave no gap.

Charley