One of the final steps to putting this behemoth to work was bringing both slabs into a coplanar state. And yes, this is far easier said than done. I had toyed with the thought of leveling the bench using hand planes, but as I progressed to this point, my inner neanderthal took a back seat to the more modern inner woodworker and I accepted that I would follow Marc's & Nick Offerman's tutelage and use a router and router sled.
In all honesty, I actually followed Marc's process damn near exactly...right down to the green coated 1/16" wire cabling to bring the router sled rails into parallel. But more on this in a moment.
After jointing and planing a couple of 2x6 fir boards I lightly clamped each one to the sides of the bench and strung my line in an X.
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Leveling Rails Ready[/caption]
Let's talk about this for a minute because this is one aspect that I think Marc didn't touch enough on in his demonstration of the process. I admit, that after watching his video a few times I was always left with this gnawing feeling that something was missing. I actually started the process with some heavy masons twine from my tool box when it dawned on me what that feeling was. The process that Marc was demonstrating, relied heavily on the use of a material that wouldn't compress underneath one of the lines. The reason behind this is that for this technique to give you the most accurate alignment, one line needs to be placed over the opposing line at the exact height/thickness of the line that you're using. So if you use a material that is compressible, you're going to wind up with a twist in the surface you're flattening as one corner will end up higher than the remaining 3 in order to allow the lines to pass each other. However if you're able to raise one line the exact thickness of the 2nd line, you'll be able bring them into that sweet spot of just kissing; resulting in a coplanar set of rails. Clear as mud? Yeah...I thought so...Over all, Marc did an awesome job documenting this process so don't think I'm bagging on him...I just think he needed to give a bit more information on the type of line to use and why.
So...with that in mind I happened across the same line that Marc had used while looking through the local giant big box hardware store...which honestly worked awesomely. From there it was a simple matter of building my router sled using some 3/4" Baltic Birch ply. The only issue that I ran into was a tendency for the sled to slide out of place side to side when in use. I remedied this by clamping a piece of scrap to the very edge of the sled, ultimately limiting the side to side travel.
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Router Sled[/caption]
Ultimately I found that the rear corner of one end of the front slab had twisted up by about 1/8", what this translated into is about 3/16" of the top being removed. I'm sure I don't need to say it, but this produced a fair amount of chips...it was like it was snowing maple flakes in the shop...
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Maple chips pile up like snow[/caption]
Even with the large flattening bit I used, the entire process took a bit of time to complete. I had to hit the top in 3 different sections in order to keep from burning out my router because of the strain the larger bit and the amount of heat the motor built up after a number of passes...
As I worked across the top everything went swimmingly...that was until I hit the spot...and by the spot I actually mean two bark inclusions, one of which held a cut nail. Thankfully as I crossed the inclusions the router bit cut through the old cut nail without issue. The router actually jumped more when it hit the first inclusion without the nail. You can see the router jump gouge just to the side of the inclusion to the left in the picture below and the head of cut nail shining merrily away in the right.
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Mystery Bark Inclusions[/caption]
Another issue I ran into was one of my router bit not creating a truly flat surface...it more dished out the surface rather than flatten. Thankfully the dishing issue wasn't deep enough for me to really fret about.
I also had to remove the cut nail or risk damaging work pieces as they slid across the head of the nail. It would also cause issues if I ever ran a plane blade or chisel into it...let alone the issue of ever having to re-flatten the top. The nail was embedded enough that I couldn't simply pull it and the steel was soft enough that I couldn't really get a grasp on the head in an effort to pull it with a variety of tools. So I turned to the thought of drilling it out. I remembered from my days working construction that I had seen a drill bit for plumbers and electricians that was made so it would sheer through any nails that it might hit, so off to the hardware store I went. The options were fairly limited, but I actually found what I was looking for, an Irwin demolition speedbore bit.
With bit in hand I turned back to the process of getting rid of that damn nail. When I started drilling it out, the nail essentially popped right out...or more to the point wrapped itself around the tip of the bit rather than getting chopped up into glorious little metal shavings. In retrospect I'm actually quite happy that it decided to put up a fight; it'll serve as an interesting bit of history to bench and I'll always wonder how this nail (and the one on the bottom of the slab, as I'm sure now that that's what it is) came to be embedded in this piece of maple.
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Cut Nail Drilled Out of the Rear Slab[/caption]
Now that the nail was out of the way I was left with 2 holes that needed filling. Thankfully I had a tube of 5 minute Gorilla Glue Epoxy on hand and used it to fill each hole. After letting it set for an hour it was cured enough to scrape flush to the top and I was ready to move on.
[caption id="attachment_585" align="aligncenter" width="300"]
5 Minute Gorilla Glue Epoxy[/caption]
With the slabs now coplanar and the voids filled with epoxy I turned my attention to evening out the slight dishing of each pass of the router bit. I opted to give this job to my random orbital disc sander with 100 grit pads. I was worried that the 100 grit would produce a surface that would be far too smooth for the top of a work bench, but it actually produced a nice finish. It evened out the finger nail edges and dishing left by the router bit and actually gave the top some nice bite.
Now that the top is flat and coplanar the only thing left to do was to reinstall the leg vise and start thinking about the finishing touches...
Up next: This Is The End, Beautiful Friend, This Is The End!
Total Build Time:
- 1.5 hours (lumber selection, transport & stacking)
-4 hours (Top Slab milling)
- 1.5 hours (slab prep and glue up*)
-0.5 hours (preliminary flattening of both slabs)
-0.5 hours (Final rough slab milling)
-0.5 hours (trimming end and bringing into flat & square)
-1 hour (cutting and finishing tenon)
-0.5 hours (milling and laminating end cap)
-2.5 hours (milling screw cavity support & routing screw cavity includes markup/layout)
-0.5 hours (routing mortise in end cap)
-0.5 hours (fine tune end cap fit)
-2 hours (drilling and installing end cap includes markup/layout)
-1 hour (milling rough stock for dog hole strip and laminate cap)
-2 hours (production of dog hole template & routing of dog holes)
-0.5 hours (glue up of dog hole strip and laminate cap)*
- 0.5 hour (glue up and alignment of dog hole strip to front slab)*
-0.5 hour (milling of front slab dovetail strip)
-1 hour (set up and layout of End Cap Dovetail)
-1.5 hours (milling and fine tuning of End Cap Dovetail)
-0.5 hour (front strip/dovetail glue up)
-3 hours (routing front slab & installing tail vise)
-22 hours (cleaning, coating, baking and cooling of Vise hardware)**
-1 hour (initial milling of legs)
-1 hour (leg glue up)*
-2 hours (milling base rails to final dimensions)
-1 hour (milling of legs to final dimensions)
-2 hours (setup and cutting leg tenons includes Mr. Cock Up)
-2 hours (layout & cutting of mortises in legs, drilling dog hole access & hold fast holes)
-1 hour (cutting rail tenons)
-2.5 hours (fine tuning mortise & tenons & dry fitting base)
-1.5 hours (cutting and dimensioning bench dog stock)
-1 hour (routing bench dogs to profile)
-0.5 hour (fine tuning bench dogs to shape)
-1.5 hours (bench dog assembly & fit-n-finish)
-0.5 hour (dimensioning & laminating chop stock)*
-3 hours (dimensioning & carving parallel guide)
-1 hour (fit & finish of parallel guide)
-2.5 hours (design & shaping of chop)
-0.5 hour (drawboring parallel guide & chop)
-2 hours (shaping & finish of parallel guides)
-4 hours (installation of nut block, parallel guides, phenolic bushing & fine tuning vice operation)
-0.5 hour (marking drawbore locations & drilling them out)
-1.5 hours (making dowel plate and dowels)
-1 hour (assembling the base)
-2 hours (leveling the base & mortising slabs)
-1 hour (fine tuning slab placement & attaching slabs to the base)
-1 hour (milling router sled rails, positioning the rails & building the router sled)
-2 hours (flattening top with router)***
-1.5 hours (drilling out inclusions & filling with epoxy)
-0.5 hours (fine tuning top with RO disc sander)
-89.5 hours total
*I havent included my clamp time in these figures if you want to add those figures in, each glue up sat for 24 hours
** Im including the baking of my vise hardware into my build. If you dont want to include this reduce the total by 22 hours
*** With a heavier duty router this process would have been about an hour