Cutting the Top and building the Under Carriage
With the frame assembly dry fit and the bench surface placed into the leg joinery, I carefully place the granite insert on top to establish its permanent location. My initial thoughts were to install it off to one side but after laying it on the work surface and imagining how it would function in daily use, I decided to center it. This decision was based on the under carriage bracing system and the drawer hanger locations. I also felt that it would be more comfortable centered while in use and may keep the bench a little more balanced. So now that I know where I want to place it I carefully lay out and scribe around the perimeter.
Once I have the lay out complete it's time to start thinking about just how I'm going to make this cut-out! My first thought is to use my frame saw and after drilling a pilot hole through the oak, dis-assemble the saw and thread the blade through the opening as you would on a scroll saw. I proceeded to do this and made the first long rip cut down the front of the piece but hit a wall when faced with the cross cuts. The frame saw only has a 6" throat so it wouldn't work for the cross cutting. 1" oak is a challenge at the best of times and the light blade of the frame saw was really pushing it. I decide to use my Japanese ryoba saw, this is the one without a back and has both a rip and cross cut tooth configuration. I use a brace and bit and bore a series of holes along the cut line to fit the ryoba and get things underway. In the next shot you can see the first rip cut at the rear and the holes drilled to allow the blade of the ryoba to pass through.
In a power tool shop this procedure wouldn't be a big deal, maybe a jig saw would suffice or even a table saw with the piece placed over the blade and then carefully raising it up through the work. In my shop however, a little trial and error and I'll have the cut out complete. The ryoba works its way through the oak. Some people have a hard time with pull saws binding and teeth breaking but if you don't force the cut and let the saw do the sawing, even on this hard white oak it's a relatively easy task.
It's not pretty but it worked! I'll clean up the inside edges next.
Again with a nice wide chisel I carefully work my way around the area taking small bites. I begin from the underside and chop down a little more than half way. I flip the piece over and finish the job from the top where its seen. I have a corner chisel and this is a perfect application for it. These are a kind of specialty item that you could indeed live without but they do come in handy from time to time.
I dry fit the granite and note any tight spots along the edges. I mark them and remove the slab to slowly and carefully pare away the 'fat' to achieve a perfect fit.
Now that I have the surface cut-out complete I turn my attention back down to the frame and dimension the final rear stretcher. This 2" oak is placed at the rear top and the back of the work surface will sit on it when complete. So again with the mortise chisel I chop out the cavity.
The tenons in the oak are off set to allow for the dado I'll plough out next. This groove will hold the under carriage cross pieces, both the granite insert supports as well as some drawer hangers.
My plough plane is the perfect tool for the job.
With the frame joinery finally complete, I'll start to lay out the components for the granite supports. These are made from some hardwood offcuts I had, in this case some birch and walnut and I dimension them so that when installed the granite will sit slightly proud of the surface. When I say slightly proud, I mean no more than the thickness of a standard sheet of writing paper. The back of the supports will sit in the dado we just cut into the top, rear stretcher and the front will be screwed and joined into two recesses on the underside of the front apron.
I begin as usual by laying these out.
I approach this like I would with chopping a half blind dovetail, clearly scribing the edges and the depth of the cavity. The main difference between this and a dovetail is the dovetail is usually chopped into the end grain of a board while this is running along the grain. Care must be taken to insure I don't chop too deep and split the piece. I begin my making some saw cuts to establish the outer edges and then with a chisel begin removing the waste.
In a power tool shop this procedure could be easily accomplished with a router and a jig so with that in mind I'll get mine to complete the cut-out.
Gotcha! Did you really think my router would have a 'plug' attached? Taking shallow passes, I work my way down with the router plane until I reach my desired depth.
Then with a chisel I clean up the corners and dry fit the supports. I'm looking for a nice tight fit- how tight? With the apron clamped in my face vise I'm able to press the supports down into the openings and with out any support they're able to sit proud without sagging or falling out.
I'll re-assemble the bench top pieces and dry fit the granite supports.
When I'm happy with the fit and the depth of the components are well established, I'll take my awl and mark for some screw holes. I need to make all of these pieces removable for times when I want to re-surface the bench top. This is also why the front cross member on the tool tray is also removable. My vintage hand drill with a modern counter sink bit enables me to drill and countersink in one pass.
From here I begin laying out and measuring for the drawer hangers. They will also sit in the rear apron dado and are cut for a snug fit. The two inner hangers will need to be shaped to fit around the profile of the granite. I approach this as I did when removing the waste on the underside of the feet. I make a series of saw cuts to establish the depth and then chisel out the waste.
In the next shot you can see the shaped drawer hanger in the fore ground and the side example in the rear. These will also recieve a dado for the drawers to hang in.
To add some added insurance that all of these pieces do what I'm hoping they'll do (and that's holding a heavy granite slab and two drawers tightly to the bottom of my workbench) I'll add some pocket hole screws that will secure it up into the bench top. A pocket hole jig is a useful tool in the hand tool woodshop but is usually associated with power tools.
Here, with a special bit chucked into my brace I can easily drill the holes and am ready for a final dry fit. You may notice at this point I only had two of the four drawer hangers installed; truth be told I wanted to see if this system would work and when it did I went back and made the two for the left hand drawer.
I was planning on showing the frame glue up in this post but looking at its length I think I'll save it for the next one-
Interesting post. That blue Kreg jig sticks out like a sore thumb, though!ReplyDelete
Where you cut out the notch using chisel + router plane, I'm wondering why you used the router plane for removing the bulk of the waste? I don't have much experience with a router plane, but I'd worry about keeping the edges well-defined, so I'd probably do the bulk with chisel, and just use the router plane for getting the flat/level bottom.
you're right, the kreg jig does stick out- maybe i should paint it? ;)
as for the router plane it was used to establish the depth...the back of the cavity was pared with the chisel and the sides were sawn and then cleaned up. the router just makes for a more accurate bottom as opposed to chiseling it on the horizontal.
thanks for the comments!
I'm a newbie when it comes to hand tools and was wondering how you cleaned up the center cutout for the granite stone. I see the pic where you use a chisel to remove the bulk of the material. It looks quite smooth! Is that all done with the chisel or did you also use a smoothing plane?
thanks for the comment-
it was done with only the chisel- a very sharp chisel to get that smooth surface in the oak end grain.
Great Blog post! It never even crossed my mind to use a pocket-hole-jig for neander-joinery!
One question I had, how are you planning on joining the center drawer hanger. The rear sits in the rear groove, but I'm missing how the front is attached.
thanks for the comments-
the front is just pressure fit and screwed- doesn't sound like much but because of the rear tenon and the actual height of the drawer hanger, even before I screwed it in it didn't move.
What is your reason for setting the granite slab a few thousandths proud of the bench top?
Would an Azebiki saw have worked for starting the cut in the center of the top? Do you have/use one? (they say boat builders love them) I've never used one, but had the impression that they are ideal for starting cuts in the center of panels. Any thoughts?
Eric, the reason for the few thousands proud is in both execution and the day to day workings. Making it sit just slightly proud is actually easier than trying to have it perfectly flat to the oak and my thoughts were the oak will move as all wood will and the tiny clearance will hopefully keep things closer to true. Also, in use I thought that if it were flush with the top, when I was say, flattening the sole of a plane for example, then I may run the risk of hitting the edge of the wood while working. make sense?ReplyDelete
the Azebiki saw was on my mind for this- I don't have one any more but would have purchased it for this if I thought it would have worked. Maybe it would have but I used to use it on 1/4" marine plywood and it worked pretty well, but sawing down through this oak may have had limitations...now that you have me thinking about it again I'll probably pick one up and try it ! Lee Valley sells one for less than $50 bucks...hmmm...
Thanks for responding. Actually, I was looking at the Azebiki Lee Valley sells this morning, which is what led me to ask the question. It seems like one of those tools that one could find useful for a number of random tasks. I was thinking it might even come in handy for clearing out waste in larger joinery tasks. Anyway, thanks again for responding, and if you do end up ordering one I'd love to see any unique uses you find for it in your posts.
Hello Tom.Great book, and the dvd was a wonderfull supprise.The best part for me was finding out that you do such great work in a 12x14 space.For many of us that answears the big question of where can I do that kind of work.Thank You Tom. LouReplyDelete