I was talking to Chris Wong today about the way we put dog holes in benches and for some reason was transported way back to the very beginnings of my getting serious about woodworking.
I was moving from Vernon BC with some shop space, to an apartment in Coquitlam BC and really wanted a small workbench to do hand tool work. I had purchased Chris Schwarz’s book, “Workbenches” and had been given some 4 x 6 Hemlock boards that I thought would do for a small 6 foot bench. It had to be something I could build and then break down for transport, so I had to drill holes for bolts. I had seen flat bottomed holes in wood furniture before to seat washers, but had no idea how they were drilled as I had only ever had metal drill bits. I made a trip to a shop in town that had wood working equipment and they introduced me to something called a “Forstner Bit”.
Wow! They could drill a hole larger than a 1/2″, make a flat bottom for a washer to seat in and made a really clean cut, its a miracle! At the same time the sales guy showed me something called a “Brad Point” bit. I ended up leaving with a set of Brad Points and an 1 1/8″ Forstner to install the lag bolts that were to hold my bench together.
I finally had my little 6 foot bench built and ready for transport. I could break it down, set it up, it was solid, no problem. Now for workholding – Schwarz said this was really important.
I had decided on using 3/4″ dogs, as that was a common size I had read about and thought I should install some holes before I moved the bench. Back to the tool store. “How do I drill a 3/4″ hole?”
“Well, a Forstner bit will drill a nice 3/4″ hole”
“Okay, I’ll take one of those”
I marked out a pattern 2″ in from the edge and 3″ apart running down the length of the bench. I chucked my brand new 3/4″ Forstner bit into my 1/2″ drill, set it on the first mark, pulled the trigger and pushed. Well, chips flew for about 20 seconds and then things started to bind and smoke came forth. Okay, drilling through 4 inches of Hemlock is not as simple as it might seem (being a softwood). Pull the bit out, clear it, run it in, and out and in and out, well… you know the drill, pardon the pun.
The hole is through. I had bought some 3/4″ dowel at the local hardwood dealer and gave it a try. Nope. I look in the hole, I have stair steps running off on an angle. Okay, I didn’t keep the drill vertical. Try another hole. Nope. and some more. @#!!?
I called two of my kids out to the shop to watch the 2 axes and keep me straight so I can concentrate on the in and out. I now have the drill perfectly vertical on the hole, I have the rhythm of the clearing to keep the bit cutting. It’s all good, let’s get the rest of the dog holes done.
What is your guess on how this turned out?
I did manage to get some dog holes to work, although, all of them had problems. What I found out later through research was that the bit was “drifting” sideways in the wood through the changing densities of wood, “sliding” on top of the harder layers. Lesson learned, the more stable the base the more accurate the hole. In this case, the base was the actual outside cutting edges of the Forstner bit and they were going were the wood grain took them.
How did I fix it? I later discovered the “auger bit” that helped me clean up the crooked holes. I also added more, still not getting them quite plumb, although, a great deal better than my Forstner Follies.
The only way I found to drill the dog holes dead plumb was with the plunge router, which automatically ensures the holes are bored straight and square, and a 3/4″ router bit (like the one included in our Easy Dog Hole Kits) I now have a few of the router made holes in my bench too, (yup, I have a lot of aeration in my bench) and they are great. I will use the router (as much as I hate it) to do my next bench top when I can find the time to build it.