Monday, June 28, 2010

The Craftsman 10" Contractor's Saw Model 21833 - Part 3

In Part 1 I talked about the unboxing and a quick summary of the assembly of the saw.
In Part 2 I talked about quality issues with the saw blade, and the minor tolerance challenges I had.
Here in Part 3 I will talk about dialing the saw in.

The instructions that came with the saw (new ones with photos, not the old ones. If you get the old ones without photos, download the good ones from the Sears website) were quite good. If you follow them IN ORDER you will have a nicely dialed in saw.

There are five critical adjustments and a few minor adjustments. For now we'll talk about the critical ones:
  1. Saw blade to miter slot parallelism
  2. Wings to table
  3. Fence to blade/miter slot and fence to table
  4. Miter gauge
  5. Riving knife and guard system
Let's start with the blade adjustment. 

The instructions give a great way to measure the blade front to back parallelism. One thing they don't tell you... Do NOT raise the blade 100%. Keep it a bit shy of fully extended. The design of the trunion mounting causes it to twist a bit when it hits the stops, and this will throw off your measurements. Clamp a dowel or stick to your miter gauge (doesn't matter if the miter gauge is adjusted for this). Set the dowel so it just touches a tooth at the front of the blade. Mark that tooth with a sharpie or something. Rotate that marked tooth to the back of the blade and slide the miter gauge with dowel so it's pointing to that same tooth. Is it just touching exactly like before? If not, you need to adjust the trunnions.

Mine was 1/64th off, so I followed the instructions. I removed the six screws on the panel at the rear of the saw and located the 4 bolts mounting the trunnion to the table. The manual said there are 4, but the picture only shows three. The fourth is way up front, hidden from view. Reach up there and feel around and you'll find it.

I loosened all four bolts and tapped the trunnion with the heel of my hand until it was fully aligned. There's one angle where you pretty much have to hit the blade shield so be gentle. Once it's aligned perfectly (take your time, there's no rush here), tighten two bolts - One in the front, and one in the rear. Now measure again. This is making sure you didn't knock it out of alignment while tightening the bolts. If it's still perfect, tighten up the other two bolts.

In my saw, the rear panel was one of the places with some tolerance and alignment issues. When you put it back on, only start the threads on the six screws. Then tighten the middle ones first, and diagonally tighten the rest. Middle, middle, top right, bottom left, top left, bottom right. And so on. This will keep the panel from warping or pulling the cabinet out of square.

Now for the wings.

As with most inexpensive saws, the wings are stamped steel. The enamel coating on them is crap, just like most of the paint on this saw. So be gentle... I got a set of scratches on mine from laying it face down on the concrete floor. Whoops!

I'm assuming you have a good straight edge around. I have two. A steel high quality 48" straightedge and an aluminum 48" level. Both are very straight. I use the straightedge simply as a reference to check the level, then the straightedge goes back on the shelf. The nice thing about using the level is it will stand there while you work. You don't have to hold it. Makes life much easier!

I first mount the wings on both sides, getting the bolts only finger tight. Then I place the level on the table at the middle of the wing and tighten that bolt a little more, just enough for the lock washer to start to compress. Then I move to the front and do the same thing. By the time I get to the rear, it should already be on a plane with the table top. Crank all the bolts down and double-check that they stayed put.

At this point, before doing ANYTHING else, clean the table and wings from your greasy fingerprints (you cleaned them before assembly as the instructions said, right?!?!?!) and apply a coat of quality wax. I avoid automotive waxes for tool use due to the additives they have, instead preferring a good quality furniture paste wax. I like Bowling Alley wax, which is available at Ace Hardware and elsewhere. But use what you prefer or have handy.The wax will help protect the paint and the table surface from light scratches, and make cleaning it up later much easier. Plus, if you're in a humid area, your table top started rusting the minute you cleaned the shipping grease off it!

That beautiful fence.

I like this fence. There are some complaints about it out there, but the design is wonderfully adjustable, and light and smooth. No, it's not a Bies, but it's much better than it should be for the price.

Assuming you mounted the rails per the manual, this will be a breeze. Follow the instructions!

Let me say that again: Follow the instructions!

If you make the adjustments IN ORDER, the fence will work wonderfully. Keep in mind that all of these adjustments are methods of applying pressure to the plastic glides inside the fence. So don't overdo it. If any adjustment causes the fence to feel tight, or take effort to move, back it off and try again.

Align it to the miter slots, NOT the blade. You've already aligned the blade to the slots, so use that slot as your reference point. Otherwise you could be compounding errors and end up with a kickback machine instead of a quality saw.

The miter gauge.

The miter gauge that comes with this saw is a joke. Maybe I got spoiled with my Incra I used on my Rockwell Contractor's saw, but this thing... Ugh. The face isn't machined, it's enameled. The "stops" are just adjustable screws you bump against with a thin pin. And they were far out of adjustment out of the box.

It was such a mess, I decided to align it to 90* and lock it down. No messing with the rest. That is enough to build a couple sleds, while waiting until I can get another Incra.

Don't spend any time on this thing. Buy a quality miter gauge and put this one on a shelf somewhere.

The riving knife and guard system.

My favorite part of this saw is the riving knife design. The knife itself is fully adjustable from completely hidden to all the way over the blade. All with a lock knob and a release button. Super easy.

For 90% of the cuts you'll make, the guard can stay in place, with the riving knife all the way over the top of the blade. It's a slick system. For the other 10% of your cuts, you lower the riving knife just below the height of the blade and you still get the kickback protection! I can't imagine a need to have it completely hidden, but if I think of one, I'll let you know.

The adjustment is a matter of aligning the knife to the right side of the saw blade. That's it. And mine was perfect out of the box. Again, follow the instrucitons!

That's it for dialing it in. If everything is right, make sure the saw is flat on the floor (wheels retracted) and plug it in. Make sure you're standing off to the left side of the saw (motor side) and turn it on. It should smoothly come to speed in moments. There should be no vibration on the saw, and if you either cleaned up the stock blade, or installed a good quality blade, there will be no vibration visible in the blade either.

A popular test of saw performance is the "Nickel Test". Basically, you make sure the top is level to the world, and stand a nickel up on its edge. Then you turn on the saw. If the nickel stays standing, you have a finely tuned saw.

After shimming the legs (my floor is nowhere near level) I did the nickel test on this saw. It passed.

Next post will be a summary review of the saw after running some wood through it!

Sunday, June 27, 2010

The Craftsman 10" Contractor's Saw Model 21833 - Part 2

In Part 1 I talked about the unboxing of the saw, and a quick overview of the assembly. 


Here in Part 2 I will discuss the issues and challenges I discovered while putting this bad boy together.


First, I'd like to talk about saw blades. A 10" circular saw blade is usually attached to an arbor with a nearly 1:1 relationship with an electric motor. That motor is usually a 3450 rpm motor in table saws. So the arbor is spinning at 3450 rpm. The edge of the blade is moving at nearly 100 mph! Also, a blade gets pretty hot plowing through wood causing heat expansion and possible warping. That is why you see the little curly cutouts in some of the better saw blades.


Now, if a saw blade is under all these stresses, you want it to be absolutely clean, smooth, solid. You want it to mount perfectly flat against the arbor. You don't want any pits or voids in the metal. Well, the blade that came with the 21833 meets NONE of those things. The arbor hole has pits *AND* burrs. There are pits throughout the blade. And the hole doesn't even fit solidly over the arbor, being a smidge sloppy. (Note that my old Delta Industrial blades have NONE of those problems. No slop on the arbor, no pits, no voids, and no burrs!) 


The first two pics in this post show both sides of the blade. That stuff makes me incredibly nervous. So that blade will *not* be used on my saw. I'll stick with my 9" Delta Industrials for now until I can order a nice Freud or Forrest. 


During the saw's assembly, there were some challenges with tolerances. Not a huge problem, but be ready for them. Things like bent steel not being bent exactly as it should. Massaging the metal by tightening screws a little at a time in whatever center-outward pattern fits the number of screws will take care of it. Also, a couple of the M8 screws had burrs on the threads. I chased those threads with a metric die set I have so no biggie. But if you don't have one, a small file should take care of it. Or call Sears and have them send you some replacements. 


One kind of biggie was on the front rail. The fence rails are each made from two parts butted together with a plastic coupler in between. Aside from the PITA that the rears were, the design seems solid. However, on the front rail, where the two parts come together, there was a raised lip on each side. This made a bump whenever the fence mount was moved over it. Plus, I had to account for those lips when adjusting the fence, so it was never as tight as it could be. I decided to sand those lips off rather than deal with the challenges of leaving them in place.  Made a huge difference in how smoothly the fence mount moved along the rail in that spot.


Next I'll talk about tuning the saw in Part 3. It was much easier than I thought it would be!

Saturday, June 26, 2010

The Craftsman 10" Contractor's Saw Model 21833 - Part 1

The Unboxing
I got a new toy! The Craftsman 10" Contractor's Table Saw, model 21833. It was on sale for $409.99. Sweet...

The delivery guys manhandled it into my garage. The box was WAY bigger than I expected. Though I've never bought a saw new before.

There is damage on the corner of the box. I was leery, but as you can see, once I opened everything up there was no damage. The styro did its job.

There are LOTS of parts to this. I can see why reviews of this saw talk about the difficulty of assembly. If you aren't careful, and follow the steps EXACTLY as shown in the manual, you're going to have trouble.

The instructions are really quite good. There is one bit I wish they suggested... After the saw is right side up, you're told to check the blade to miter slot alignment. Mine was off by 1/64th. To adjust, you need to remove the back panel of the cabinet. 6 screws. I made the adjustment and then put the panel back. A few steps later, the instructions said to remove the back panel to install the rear fence rail. Grrr... If they had said, "And leave this panel off as you will need to remove it later..." I would have been happy.

The other annoyance is that rear fence. You need a 4 year old's fingers to get the nuts on those bolts. With my fat 40 year old fingers, it was a real PITA. Adding a half inch to the table depth would have made this MUCH easier. 

Otherwise, it went together well. 2 hours to assemble, 2 hours to dial it in. Not as bad as I had expected based on the reviews on the net.

Enjoy the pics. In Part 2 I will talk about the dangerous saw blade, and cleaning up some burrs.

Part 2: