Monday, September 7, 2009

Rebar for Mitered Frames

A neighbor asked for a favor: she wanted a frame for a bathroom mirror, but the mirror could not be removed from the wall.  Effectively she wanted a frame applied to the mirror's glass since there was next to no clearance on the sides.


I created the frame from quartersawn sapele just 1/8" wider than the mirror so the existing inch of clearance to the walls would still show.  This will be applied with a bead of silicone directly to the glass.

The trick was she wanted a mitered frame.  Since it was to be applied, it was really just the top portion without the typical back.  So rather than the frame being 5/8" to 3/4" thick with a groove for the glass and a beveled front, all I had was a 3/8" thick top portion that was beveled.  There's no room for a miter key, dowels, etc.  Sure, with 3/8" thickness, a 1/8" thick kerf cut in the side would help, but the bevel started close to the outside edge so you'd only have a key going in perhaps 1/4"; not terribly helpful.

This is what I decided to do:


I cut a shallow recess in the back of the frame in both pieces at the mitered corner.  I also gently chamfered the edges of the miter.  I glued up the frame with regular PVA glue, but naturally the glued miter is very fragile (though I was surprised it was more resilient than I thought it would be).  This glued up corner was enough to let me do the 'rebar' glue-up.

The piece of 'rebar' is a corrugated metal fastener.  This adds a little thickness, but greatly increases the surface area of the metal.  I rubbed them down with P320 sandpaper, placed a little epoxy in the recess, pressed the 'rebar' into the magic goo then topped it with enough epoxy to bury the rebar and stay flush with the wood surface.  Naturally some epoxy flowed into the channel formed by the chamfer.

The result is a joint held with epoxy across its length and with a fairly large island of epoxy with embedded metal holding it together.  This joint is going nowhere.  Since the strong epoxy island is centered, it is capable of keeping the miter from opening from either side.

Best Varnish Jars

I had some canning jars (Mason jars) laying around for who-knows-what reason.  I started using them for varnish and they are easily the best.  The wide-mouth pints (shown here) have easy access and the two-part lid seals very well (and trivial to add plastic wrap if you like).  The lid portion is sold separately so you can toss them when they get junked up beyond reason.

Sunday, September 6, 2009

Varnishing Observations

Yesterday, I varnished a new shop hanging cabinet... something to do during blazing summer that isn't too picky if I make some mistakes due to sweat dripping off every part of me.

(It isn't done yet; hung, but the shelves are being assembled)


It was super humid yesterday and actually the several nights before. A friend thought I was nuts. Maybe, but this is why I knew it would work out well.

For the first coat, I was wiping on a thinned varnish/oil mixture (Tried & True). Since I'm putting it on very thin, it seems to me that the atmospheric humidity plays much less a role in its drying than the moisture content of the wood. I'm in Arizona so the moisture content of the wood is typically single digit. Even after humid days, the surface of the wood isn't appreciably more moist, at least not enough to affect how the varnish flows and sets up. Despite the humidity, the first coat went on well and setup with no tackiness after 6-7 hours. I could have recoated, but left it overnight.

Today, equally humid. Now, if I were to put on another oil/varnish coat, the humidity will play a role since the first coat sealed the wood (taking it out of the equation) so now it is just the atmosphere setting the second coat.

But I want a second coat cuz I'm tired of this thing taking bench space plus the pile of things to go into it is getting equally annoying.

For the second coat, I need something that will dry regardless the atmosphere so I put on a thin coat of Epifanes' Matte varnish. The matte sheen is what I want (don't like '70s high-gloss plastic oak) and it happens that Epifanes accomplishes that sheen by adding Japan dryers. Others may, too, but I know Epifanes matte will dry -really- fast.

I applied a 50/50 Epifanes/mineral spirits mix in a very thin rubbed on coat. Honestly, when I worked my way to the right and finished the right side, the left was already dry to the touch with no tackiness. Likely not set enough for sanding between coats, but this went on so well that I would only need a quick pass with a Scotch Brite.

Naturally 'dry' and 'cure' are different and this will continue to cure long after I hang it on the wall (it is garage furniture). But it is nice to know that you can get one oil-enriched coat of varnish followed by possibly several matte coats in a couple days regardless the humidity forecast. That's a nice change from the usual 1 coat/1 day-or-more schedule varnish usually entails.

Offsetting Domino depth

Currently, I'm waiting for the new 4mm Dominos and cutter to arrive at a local store. These would solve my problem immediately.

But, no need to wait.

I need to put Dominos into 12mm ply sides and into 1/2" wide oak "banding" that will form a flat sideless drawer for my shop (all my drawers are like this in the shop and I find them too useful).

Problem: 5mm Dominos will fit into the 12mm ply, but the minimum depth of cut is 12mm, which is 1/2mm shy of punching through the banding. Just say 'no' to punching through.

My solution is likely inspired by those narrow stock spacers I discussed earlier. That is, I took 2 rare earth magnets that were 2.5mm thick and stuck them on the end of each registration pin. Now I can mortise on the 12mm depth and get basically 9.5mm deep mortises. I won't punch through. That leaves 20.5mm of the 5mm Domino to go into the ply, which I prefer anyway, so I can set the depth of those cuts to 20; the Domino really isn't 30mm; it's shy of that and everything works great.

Naturally, use strong magnets for this to make sure they stay put. I didn't have any problems. A non-magnetic version of this trick is to rip a small piece of wood 2mm thick and carpet-tape it to the face around the pins.

Domino offset pins

There's a guy on eBay selling aluminum offsets for your Festool Domino; you need a Domino with the original registration pins (round metal pins) as the new square then square plastic then plastic tab registration pins won't work with the system.

I'd post a link to the product, but it changes every time he relists. So, search for "Festool Domino Narrow Stock Spacers".


The idea is simple: cylinders of specific sizes that you can slip over the registration pins (held with a magnet) and use to register against your stock. The spacers put the mortise in the middle of stock from 1.5" wide through 2.5" wide. A side of the cylinder is flattened to allow you to drop the surface registration fence.

When building something with rails and stiles, you tend to have them in a particular dimension and likely there is a spacer for that dimension. You can now slip one on the correct pin (left or right) and drop a mortise right where you want it.

Since I got it, I originally used it on a few stiles; nothing spectacular. The latest hanging cabinet, however, used the spacers exclusively. 56 mortises in record time (besides the Domino's speed). All with no slop.

They seem pricey for what they are, but then they are exclusively for a Festool Domino so the guy knows you have money burning a hole in your pocket. Still, $55 was well worth it. If you can turn aluminum, make your own.

Digital Angle (Tilt) Gauges

I always thought those digital angle tilt gauges were cute, but not something I needed. Was I wrong.

Recently, Wixey angle gauges were on sale and I snagged one thinking it would be great to use to calibrate my SawStop that was arriving the next week. Silly... who needs it calibrated when you can simply slap the tilt gauge on the table, zero it, then put it on the blade while you set the bevel.

While playing with it, I used it to set my bandsaw blade to 90* and set the set-screw of the table so I could return it conveniently. Well, the set-screw seems to move when the saw starts up so forget it; use the simple gauge each time for accuracy to +/-0.1*.

Here's the short list of the things I used it on in the first week, and the list will grow:

  • Setting the drill press table to 90* to the drill (use a long 1/2" bit for this); remember to do it in side-to-side and front-to-back directions.
  • As a digital level; I stuck it to a 4' spirit level set level then zeroed it. Now I can put the gauge on anything and treat it as a digital level (only as accurate as the spirit level, but in this case, the digital level is only 1.5" long!)
  • As a digital winding stick; I put a level across the front of a board with the gauge on it and zeroed it. As I slid the level back, I watched the gauge to see how level the board was. I could certainly see myself using it for rails for a router in the same way. Note that I used the level because it has a flat base; you could stick it to anything.
  • Clamping up a cabinet; I happen to be making a hanging cabinet for the shop (stupid projects over summer cuz it is just too hot to be serious!). The base of the cabinet sat on the assembly table that is flat. Zero the gauge there. Now, when I put parallel clamps on the sides of the case, I pushed them up until the bar touched the cabinet on top and bottom. Now, stick the gauge on the side of the bar to ensure it is 90* to the assembly table. Perhaps a silly use, but I thought it had promise.
  • As already mentioned, setting the bandsaw table to 90* to the blade; also used it for two other odd-angle cuts for a ramp and for glue blocks.
  • Oh, yeah, setting the bevel angle of the table saw blade. :)
Other uses I can see in the future:

  • I need to put in a concrete pad on the side of the house. It needs to dip away 5* from the house to keep from accumulating water. Set the concrete form by the house and set it level with a level. Now set the form for the other side and set its height with a straight beam going from the first form to the new form; use the gauge on the beam to set a 5* drop consistently. For a guy like me who doesn't do concrete very often, this will be useful.

Now, I did see a gauge I believe in Woodcraft's catalog that allows you to hit the zero button twice in a row to make the gauge zero to true level. That would be worth the extra $2.

SawStop PCS

I received my SawStop PCS last Monday. Freaking humidity and heat kept the assembly slow.

I didn't take pictures like I intended so here are some observations I recall. Use your imagination. Add a bikini where necessary.

The saw came in 5 boxes: #1 - the saw, #2 - the extension table, #3 - the extension rails, #4 - the mobile base, #5 - the fence.

Everything was meticulously packed. All parts were laminated onto color-coded and labeled carboard. The saw, fence, and mobile base each had their own manuals since each is a choice for your system. I chose the 36" fence since my shop is crowded and honestly I prefer to breakdown sheet goods with the Festool TS75 plunge saw. Cabinet shop folks think this is a weird method-of-work.

The mobile base is integrated into the saw's base. You see two pedals sticking out the side along with two wheels out the other side. The saw sits on its original base when deployed so it isn't on wheels and won't move. The base is able to lift the whole saw, extension table included, in one easy foot-press. Lowering is trickier in that you press the release pedal with the main pedal to let it down slowly. The motion is easy, but I'm still mastering the soft landing.

Fit and finish: spectacular. I cannot find a single flaw anywhere on this puppy.

The manuals are incredibly well illustrated, photographed, and documented. The main saw manual is 113 pages and covers assembly, calibration, and usage. It also includes some simple shop projects for decent push sticks and other safety items near the back.

Overall, my calibration was limited to putting the miter slot parallel to the blade. I used the Woodpeckers' saw gauge to easily calibrate it to 1/2 a thou front to back of blade. The gauge is well worth the $70. Normally this adjustment is a time consuming frustration of whacking the tabletop with a mallet to finesse a displacement only to have it all screwed up when you tighten the trunnion bolts. Not so with SawStop: loosen the table-top bolts and use 2 hex screws to scoot the table top clockwise or counter-clockwise around a pivot point set to the front of the table. The screws push into stiff rubber blocks to be gentle. Once set, tighten the screw you loosened then tighten the table bolts; they didn't move the table top at all with the adjustment screws tightened slightly.

Holy crap, the dust collection. I have a decent DC, but I am waiting for the proper connector to arrive to connect the SawStop to it. The SawStop doesn't need a DC, but I'd imagine that the DC hose in the cabinet would get full and cause grief without an occasional connection to a DC.

With the blade guard on, the laminar flow of air from the spinning blade creates a vacuum under the guard and directs dust into the cabinet hose. When the wood actually lifts the front of the guard, you hear the vacuum open up. The dust is directed down the hose and actually ejects out the back of the saw's DC port. I had a nice pile back there that was easy to sweep up. I broke down a half sheet of 12 mm ply into 9 drawer bottoms then straight-lined 4/4 oak before ripping it into 9 1/2"-strips 60" long. The dust on the table could be swept up to a pile that would neatly cover a poker chip. The pile out the back port was fan shaped, but had definite edges so sweeping it up would be trivial. Hooking up the DC for a moment to the dust port pulled a crapload of dust from the hose. The laminar flow is definitely working well.

The fence is in Imperial and metric, which is a plus. There's a gauge on both the left and right sides of the fence (this is a left-tilt saw). It comes with hangers for your blade guard, riving knife, miter gauge, and blade change wrenches.

Speaking of blade guard, yes, I use it on a SawStop. The ney-sayers of SawStop say that it promotes unsafe practices. Dude, please... I'm not going to start putting a Jack-n-Coke on the extension table and pushing boards through with my nose because of the safety mechanism. Even if I was stupid enough to say "party on" and do stupid stuff at the saw, my wallet would remind me I'm stupid: the cartridges aren't that expensive but it will blow out your Forrest WW2 blade in the process. Add to that new underwear.

If I were forced, at gunpoint by a gun with no brake mechanism, to find faults in this saw, here's the list (YMMV):

1. I'm 6', which isn't that tall by any standard, but to see the status lamps, I need to step back and bend over a bit. I think this will go away as I get comfortable with the saw; effectively, you use it like any other saw, but if you want to touch the blade with a finger or tape measure, make sure the status lamps think the blade is stopped even if it is to your eye.

2. This fence is a nice fence, but I was awesome at moving and locking my previous fence in a fell swoop dead on. This one wiggles more in the track before the lock; I think I can fix it with the parallelism screws, but right now it is a minor inconvenience.


I will, however, feel a certain Zen for all the hotdogs I'll save with this choice.

For the curious, this was an upgrade from a Powermatic 64S. A sweet saw in its own right, but I gladly pay up-front to avoid paying for physical therapy.

Introduction

Hello,

My name is Paul-Marcel St-Onge and this is my blog about woodworking observations. I got into woodworking via 'remodeling' about two years ago. Not really sure what triggered the interest, but I generally tell people that I had too much discretionary savings lying around that needed to be spent and woodworking is easily the fastest (second only to gambling) that I know of to mow through money like it grew on trees (while mowing through trees, naturally).

I don't plan on putting up long dissertations on why your planing angle sucks and mine rocks, or why you shouldn't worship the 'Delter Unisawyer' simply because it inhabits most cabinet shops in the country. No, rather, I plan on putting up those silly observations I get from time to time and feel they might be useful. Think of this as a twit, er, tweet stream permanently homed for your Googling pleasure.

I also occasionally stream from my shop while putzing. You can find that stream at: http://www.ustream.tv/channel/half-inch-shy UStream.tv lets me tweet when I start a broadcast, which generally lasts hours. My Twitter page is http://www.twitter.com/PMSO and is generally not enlightening. I haven't streamed as often lately since my dad fell ill; instead, I do video Skype directly with him to let him pass the time as though he was in the shop.

blah blah blah, less boring crap and more observations!

Paul-Marcel