Scribing, with graphics

Instructions on scribing cabinets to walls. April 4, 2001

Q.
I build a lot of cabinets but I'm pretty green at installations. The thing I am most curious about is scribing the cabinets to the walls.

Forum Responses
I use an angle grinder with grit paper from the welding supply store. It works very well. I can scribe the end of a p-lam counter like butter with my pocketknife (well, almost). It has better control than you might think.



You can use an angle grinder, table saw, belt-sander, jigsaw, portable planer, etc. It can also depend on what type of material you're using. If you're doing a paint-grade job, and the wall is reasonably straight, you can make a straight cut with a table saw, because you're going to caulk it anyway. Also, it can depend on the quality the customer is paying for. Guys who knock out apartment complexes don't scribe at all. They use screen moulding. But, you better not do that in a million dollar home.

Use whatever method you are most comfortable with safety-wise. If you use portable tools, it's a good idea to clamp your stile down and use both hands on the tool (especially around an electric planer).

Do you know how to scribe the profile of the wall onto the stile with a compass?



From the original questioner:
That's the part I'm not sure on. I know how to use a belt sander to remove the material, but what's the best way to get the mark in the first place? Do you put the cabinet all the way to the wall and mark from there?


My preference is a belt sander. 3" and 1" work well with a 40 grit.

Using a compass (scribing tool), you scribe a line onto the cabinet following the profile of the wall or other surface. The trick is to have the cabinet to be scribed plumb and reasonably close to where it will reside. It doesn't matter what the spread of the scribe is or how far the cabinet is away from the wall, but one dictates the other. The easiest sequence is to temporarily place the cabinet plumb and adjust the scribe so that it touches the wall and cabinet at all times, while scribing a mark onto the cabinet.



This is where cabinet suspension fittings and hanger rail come in. It is very simple to hang the cabinet, level, and then scribe the trim. That done, slide the cabinet sideways for the perfect fit.


The way I do it is a little different. I don't use a typical 3/4" face-frame (but it doesn't really matter about the thickness). If I'm going to caulk the gap anyway, I usually use a tape measure and put a few marks on the stile, and connect them with a straight-edge. But, if it's a custom cherry bookcase, I'll take a little more time and make it look perfect.

I install the cabinet first without the wall side stile on. Then, I measure from the end of the top rail to the wall. Next, I transfer that measurement onto the stile. Then, I temporarily attach the stile to the cabinet exactly parallel to where it will go (this means that it will sit on top of the top and bottom rails). Tape usually holds it well enough. Now you're ready to scribe. Take a compass, with a sharp pencil, and set it to the distance between the wall and the pencil mark on the stile. With the pencil side on the stile, slide the compass down the wall. When you're done, you should have a line (straight or wavy) to cut along.



Get a good compass or dividers that lock. It makes it hard to scribe when you use those 99 cent compasses. I use a jigsaw, finished up with a small power plane to make a back bevel. Most of our installations would not be acceptable with more than a 1/32 gap.


I always like to rabbet my cabinets where they abut the wall, leaving only 1/4" thick material, which is easy to take off with a few strokes from the block plane and a sanding block. A lot quieter and cleaner.


1) Put masking tape on the stile so you can see your line.
2) Plumb the cabinet so it's right up against the wall.
3) Cut a small scrap piece of hardwood the same thickness as the largest gap.
4) Holding the hardwood against the wall and with your pencil up against it, scribe your line.
5) When using the pencil, rotate it slowly (in effect, sharpening it along the way).
6) Back bevel with a belt sander.


We use our Quickscribe whenever we can. It is fast and does an almost perfect job of scribing. For cabinets, we use separate toe kicks, which we level well, then place the boxes on. The weight of the boxes usually is all that is needed to hold in place while scribing (tall bookcases need a block or two holding them away from the wall).

Upper cabinets are still done the old way, because I haven't figured out how to hold them in place an inch away from the wall. Countertops are real easy, as long as you can move them away from the walls--it is 1 inch from the wall to where the cut is made. Paneling is a snap, too--a couple dabs of contact cement will hold it in place while scribing. Be sure to work from right to left so it doesn't pull into your work.



From the original questioner:
I have a couple of ideas for the uppers. You could screw a ledger board level onto the wall and then set the upper on it. This would leave a couple of screw holes in the wall, though. Or, if your top hang strip is in the back of the cabinet (as opposed to inside) you could put it up there. Then you could easily slide the cabinet over and run one screw to hold it.


We do use a hang cleat on the outside of the upper cabinets, which is shaped with a rabbet on the bottom. We then screw the same piece with the rabbet on top to the wall, which lets us place the cabinets on the wall and slide them around until we are ready to fasten in place. The system works very well for us, but with the Quickscribe, you need to have the cabinet 1" out from the wall for it to work. That is easy with lowers, but I can't figure out how to do it with uppers.


From the original questioner:
I was referring earlier to scribing the front stile in a wall-to-wall kind of situation. Are you referring to scribing the skin on a finished end? If that's the case, and you need your cabinet back to be off of the wall an inch, you could install your ledger board just like you usually do (this would make sure your holes are in the right spot to keep things level), then back out the screws and put something 1" thick behind it to shim it out. You'll need to use screws that are a little longer than normal.


I use the French cleat method to install uppers, also. This is how I scribe finish end uppers.

In the shop, I cut 2" scraps of cleat stock and attach them temporarily to the back outside corners of a finished end cabinet directly over the permanent hanging cleat. When I get to the job site, the cabinet just gets hung up as usual, only it will sit proud to the other cabinets the exact width of the cleat. Shim up the bottom so the cabinet is plumb, then use another scrap of cleat stock and a pencil to mark your scribe line. You are removing the exact thickness of the temporary cleat. Take the cabinet down, a couple of strokes of the block plane (I also back rabbet the sides so I only have a 1/4" to deal with), remove the temporary cleats, and rehang the cabinet.



I had toyed with this same idea a few times, but never tried it. If I make a temporary cleat out of 1 1/8" material, it should work perfectly with my scribing router as long as I plumb the cabinets first. It is one inch from the wall to where it makes the cut, so there should be 1/8" left to snug the cabinet to the wall.


I tried the above method and it works great! I connected three cabinets in a line and held the two ends out from the wall like you suggested, then plumbed all of them. I could get the whole 10' assembly scribed perfectly the first time. This was with two taller cabinets and a shorter hood cabinet between, so I was scribing four finished ends plus the bottoms of two.


There's a thread at the Cabinet and Millwork Installation Forum that deals with scribing and hanging rails. I've posted some sketches that may help illustrate the description of how to use hanging rails, and scribe in place.

Hanging Rail Sketches thread at the Cabinet & Millwork Installation Forum







I like to use the blue painter's tape (low tack), but regular masking tape works well, too. This allows you to see your pencil line. If you can hold the cabinet a known distance (say 1") from the wall, you can use a 1" block and follow that down the wall with your pencil, spinning it as you go to keep it sharp. If it is a remodel with a finish painted wall or wallpaper, I put the blue tape on the wall to keep from marring the wall with the pointer of the scribes. This is where the low tack tape comes in handy. Having your assistant hold a roll of builder's rosin paper to the wall is better protection for the wall.

The cheap dime store compass works well, but when you finish, put it back at the top as if to do it again to make sure it didn't move. It's better to use a drafting compass. The only disadvantage is that the line gets fatter as you go and you might have to tune it up afterwards.

I scribe with a knife. The knife cuts the tape and you can then pull the cut side off and there is a very clear definition of the cut line. Score once so lightly you only cut the tape. If you push harder, the bevel on the razor knife can grab and cut into or away from where you intended. Then repeat several times, applying the same very light pressure. The knife will follow the cut in the tape and will eventually score the wood. This is also a good technique on pre-finished product. A knife line often appears as a white line on lacquer.

If it is wall paneling, a countertop or a cabinet with a large scribe, I use a jigsaw upside down. After scribing a countertop, I put it on sawhorses, then hold the jigsaw under the countertop, so as I cut, I can only see the blade protruding up at me. All the sawdust gets pulled down and not thrown into my face, and I have an absolutely unobstructed view of the cut line and the angle of the blade.

For a countertop, I might first score the front edge square with a handsaw or knife where it will hit the wall. As I proceed into the cut, I tip the saw, giving me a back bevel that will allow the edge to cut into the plaster tightly where I see it and/or make it easier to fine tune with a small file or rasp by hand. I find power sanders or grinders too aggressive at this point. By cutting upside down, the oscillation of the blade does not tear out the product, even in the most delicate veneer. My jigsaw has several settings for the blade oscillation, which helps clear chips and cut faster. I sometimes deliberately use no oscillation to slow the blade down (slower cutting) for better control on very wavy cuts, as in scribing to a brick wall.

What if you only have 1/2" of scribe and cannot cut upside down with a jigsaw because there is no room? The "down cutting" blades don't work well. First there is the tape that will help prevent chip out. Hopefully you were able to use a knife. Try cutting cross grain (with the jigsaw right side up) on a piece of luan plywood. Horrible chip out? Score it with a knife first and cut a little to the waste side of the line. Better? Set the jigsaw for 0 oscillation. It will take longer but greatly reduce chip out.

In this situation I plan ahead by adding extra width to the piece I am scribing, so that I can tilt the saw so its foot rides on the waste side of the cut. This makes sure the saw's foot does not mar the good side of the cut and at the same time back bevels the cut to make it easier to fine tune and fit tightly to the wall. "But I didn't add extra width to the scribe. How do I keep the saw's foot from marring?" Add more layers of tape to the good side of the cut, but so you can still see the cut line. Then place a shim or thin piece of laminate or plywood between the saw's foot and the work. The saw rides on the shim and the shim absorbs the damage of the foot while spreading the weight over a larger area (that is also protected by low tack tape).

Regardless of what method I use, I would always prefer to cut shy of the line and tune with a (very sharp) low angle block plane, rasp or sanding block, always pushing down towards the work to prevent chip out. With a block plane, try pulling towards you rather than pushing away. I have better control that way. Also, skew the plane iron down towards the work. Not only does it help prevent tear-out, but will allow you to tune fine concave surfaces that would be skipped over holding it straight. By skewing the plane, you actually reduce the angle of the plane iron. Cut a block of wood at a 45 degree angle and place it on the table. Now set a bevel gage at 45 degrees and hold it perpendicular to the cut where it meets the table. 45 degrees, right? Now turn the wood or the gage, keeping it tight to the table and a gap will start to appear. The more you turn it, the bigger the gap. This imitates the angle of attack that the blade has with the wood and the more you skew it, the sharper the "apparent" angle of the blade becomes.

How do you scribe a cabinet that must fit wall to wall? I scribe a strip of plywood to each wall and then connect them with spreaders, creating a mock up of the cabinet where it hits the wall. Be sure to have a diagonal spreader to keep it from becoming a parallelogram. Then either place it on top and trace it or use it as a template with a router and over bearing bit to trim it exactly. You still will want to back bevel it somehow, to ease the fit.