Let me begin by commenting that, a tablesaw in traditional wooden boatbuilding had as much importance as a tuxedo on a commercial fishing boat!

There just was no need for it until the joinerwork began, be it inboard or outboard. And,if push came to shove, a significant amount of the joiner work could be done without it.

What was important, was a Bandsaw, usually more than one.

I have had a shop or two and had a tablesaw or two or three, in my life time. I favoured domestic brands or eurpopean ones.

Delta, Delta-Rockwell, Powermatic, General of Canada in the 8 to 12 inch size.

Northfield, Oliver, Moak, Tannewitz, Newman, Greenlee in the 14 and up true industrial sizes.

Robinson, Watkin Bursgren, Panhans, Martin, european makes in the 12 and up sizes.

Older machines were to my eyes made better period. Castings well aged, careful machining, tuned correctly right from the factory or industrial dealer. True horsepower ratings on the motors with 100 % or more duty cycles. If there was a shortcoming with the 8 to 12 inch north american saws it was the fence. They all followed the same pattern and were hard to keep in alignment.

Fence: Traditional fence is the one with heavy walled tubing mounted front and rear parallel to the saw table with the fence itself riding on the front member. The clamping was mainly to that front tube with an almost worthless rear clamp. Many a shop had some form of modification to that rear clamp or discarded it altogether and mounted a homemade gizmo instead.

The larger industrial models noted above had a different type fence. It was mounted on the table with precision dowel pins and a geared rack mechanism for adjustment. In fact saw tables on machines like Oliver had measurements engraved right into the table top.

Mitre slots on these larger machines were milled dovetails not just plain or T-slots.

The first real change in fences came sometime in the 1960's IIRC, with the Parallock type based on the method of mounting a Jacobs Straight Edge on a drafting board. A system of fine wire cable and pulleys. Worked well but could be a bear to fine tune and never really found favour in commercial shops.

Shortly after came the Biesmeyer type and it's copies both homemade and commercially made. It is not too bad an idea but I am hearing some negative comments about quality control and it got me to wondering whether a home made version might be the way to go from both the accuracy, versatility and monitary points of view.

As I said above the Cast Iron or CI table tops on the older saws were left to season for up to one year. If you had occassion to pass bye the foundry of say Delta or Powermatic, you would see big piles of all the CI parts used in the manufacture of all types of woodworking machinery. Jointer tables, table saw tables, trunnions, etc.. laying about outdoors in summer and winter. When the aging or seasoning time was up then the parts were brought into the factory for machining and finish. Smaller machine table tops were ground whilst larger machines were planed.

Grinding is done with enormous segemented horizontal wheels. The item to be ground is clamped to a table and flooded with coolant. The grinding wheels generate a lot of heat and that heat could warp the piece. The machines used for this type of finishing are made by Blanchard or Mattison but the process has taken on the generic name of Blanchard grinding. The result of this 'Blanchard' grinding are the swirl marks left on the surface when done. Ideally finer and finer grit stones are used to get a nice looking finish but alas that is not always the case.

The larger and better quality machines had their surfaces planed not ground. Planing is a more expensive process and is slower to do. A metal working planer is easiest described as a long horizontal motorized table with a movable gantry mounted over the table. The gantry consists of a motor driven mechanism that moves both front to back and up and down. It can be adjusted quite accurately to take off fine shavings. That is right a single or sometimes multiple cutters are mounted from the arm of the gantry.

It works like this, The piece to be planed is mounted and clamped to the table and the cutter is afixed in its mounting in the gantry. The table also moves in two directions, front to back and forwards and backwards.

So we have say a table saw top mounted on the table and it is advanced through the gantry mounted cutter with the orientation of the saw top being in the same direction as if you were standing at the full machine and the planer marks ran front to back of the top surface. After each pass of the table top under the cutter the table of the machine advances the piece( saw table top) a specific amount to the front of the machine.

This distance and the depth of the cut are all minutely adjustable by the machine operator. What we wind up with is a surface that is not smooth and flat all across but has fine ridges front to back.

Advantages of planing, almost no heat stress on the CI, very accurate therefore the top is flat right off. Disadvantages of planing, much higher per piece cost, skilled operators cost more, machine is very expensive, a real precision metal working machine.

The power type varies too. On smaller machines it is V-belt driven. A relatively inexpensive way to get power to blade. The motor is an off the shelf item with the exception of the Delta type. The motors can be bought from a number of manufacturers. The same with the V-pulleys, off the shelf and vary in quality and balance from one source to another.

On larger machines there is the choice of ( 2 ) motor types. The V-belt driven one and the Motor on Arbor type. Both are dealt with much differently that the common off the shelf motor V-belt smaller machines. The motor for the V-belt larger machine has all components balanced ie: motor armature, V-belt pulleys, V-belts are muliple and carefully matched also. The Motor on Arbor is a specially made motor with the arbor part of the motor armature, fully machined and balanced and a special design to fit to the trunnion under the table. Not an off the shelf from any electrical motor manufacturer type item!

Trunnions are another item that is done differently between the two levels of table saws.

Smaller machines have the trunnion cast and machined reasonable well but,with the larger machines the trunnion is more carefully machined and the method of mounting is different too.

Smaller machines have cast bosses on the underside of the table that are machined and tapped to accept the trunnion mounting bolts, the trunnion has slots to allow for adjustment. The larger machines have precision dowel pins fitted to some of the boss type fixtures under the table top and the bolts are really just for mounting as the dowel pins assure proper alignment.

On the matter of old vs.new.

I am aware that most here are Amateurs ( in the true sense of the word ) that have neither the money nor space to accomodate a larger machine either old or new. So that leaves smaller machines, 8 inch, 10 inch or 12 inch.

I believe in the old axiom of mass equals accuracy in woodworking machines.

Older machines have thicker well seasoned table tops, thicker trunnions and better cast iron.

Older Powermatic and General ( including new General) were made with Meehanite formula castings.A more expensive but finer type of cast iron. Delta and Delta Rockwell were made from their own cast iron formula.Which in my experience seems fine on the older Deltas.

Motors today are not as ***under rated*** as were older motors. I mean today motors are just within their listed ratings whereas the older ones were far more powerful and durable for their ratings.

Motor construction is of less quality today too. Cast Iron end bells are a rarety, in the past all industrial motors came with that feature.

I have worked in shops with older and admittedly larger machines that were 40 years old and with the original motor. These were in the mill where ladders, cabinets, all interior and exterior joiner work was made. No question about the accuracy of the machine just push the button and go.

Personally I have ***NO*** experience with the current Pacific Rim machines so cannot comment on them but, there is that persistent buzz in my ear.....You Get What You Pay For!

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