This blog chapter discusses the final upgrades I made to my Model R4511 tablesaw.
Upgrading the Blade Insert
As with most tablesaws, the stock blade insert is a metal die casting with a wide slot to accommodate both vertical and bevel cutting. However, the wide slot does not provide adequate support of the material, particularly when cross cutting. The lack of material support adjacent to the cut is especially noticeable when cross cutting hardwood plywood, which frequently has very thin face veneers of brittle materials, resulting in chipping and tearout of the face plys along the cut surface.
This photo shows the metal blade insert that was furnished with the Model R4511.
A common solution to the tearout problem is the use of a Zero Clearance Insert (ZCI), which has a blade slot which exactly matches the particular saw blade being used. Many of the ZCI’s in use today are shop made from a variety of materials, including plywood, MDF, hardboard, solid hardwood, phenolic, Corian, and others.
A ZCI is usually made by using the original stock blade insert as a pattern to establish a periphery which will match the opening in the saw table top. Frequently, woodworkers fabricate a number of ZCI’s, dedicating each one to a particular blade size. ZCI’s can also be made for specialized cutters like dado and box cutter sets.
In many cases, it is possible to use the same ZCI for two different blades by flipping the insert end-for-end and putting the second blade slot on the other side of the insert, thereby saving insert material ( which might be expensive or not commonly available).
The photo below shows a ZCI I made for my Model 4511 from ½ “ sheet phenolic material I was able to obtain from fellow LJer noweyrey1. Altho many folks use a flush trim router bit to size their ZCI blanks to the original insert, this one was cut to size on the tablesaw, including the corner chamfers, for convenience, since I don’t have my router table built yet. The corner radii on the original insert are fairly small, so it was more expedient to just use chamfers instead. There is a #10-24 set screw near each corner of the ZCI to permit leveling to the table top.
You sharp-eyed readers will note that the blade slot in the ZCI does not exit the end of the insert. Tho I can’t recommend this practice to you, I prefer not to use the guard/splitter furnished with the saw. In my opinion, this device obscures my view of the blade, making a more unsafe condition than omitting the device and leaving the blade exposed to view. Also, although this saw will accommodate an aftermarket riving knife, I have not invested in one or felt the need to fabricate one at this time – although that is something I might consider later.
Miter Gage Upgrade
The stock Ridgid Miter Gage is a well-made unit with a cast aluminum head and steel guide bar. Adjustable stops are furnished at standard bevel angles. The guide bar also has four set screws to adjust the fit of the bar to the miter gage table slot. After removing the T-bar, this miter gage could probably be used on my bandsaw.
I chose to replace the stock miter gage with an Incra V27, which I was able to purchase at a good sale price some time ago. I chose this unit mostly for its absolute settable accuracy in 5º increments, due to the use of precision laser cut detents in the outer periphery. Since this unit was first marketed, there are newer ones (at higher prices) which are very popular with woodworkers, that have 1º increment detents. This unit employs adjustable plastic washers to improve the fit of the bar to the miter slots. However, I have found that the abrasive surface of the sides of the miter slots in the granite top tend to cause excessive wear of the plastic washers.
Power Switch Upgrade
The stock power switch, shown below, worked well. It is a flip toggle type which is rated for both 110VAC and 220VAC. Altho I chose to replace it on my Model R4511, I think I will use it to replace the pushbutton switch that came on my Grizzly G0555X bandsaw, which seems to have a hard to operate pushbutton mechanism.
I chose to replace the stock Power Switch with the Grizzly Model H8243, Paddle Type Pushbutton Switch shown below because I was used to using a paddle type switch on my previous General Model 350 cabinet saw. The large paddle makes it easier to turn off the saw with a knee in the event of an emergency or a situation in which both hands are required to secure the material for the cut being made. This change also required changing the switch box to accommodate the new switch.
Input Voltage Conversion
The 1 1/2HP motor on the Model 4511 came from the factory wired for 120VAC. The motor nameplate rating lists the current draw as 13A at 120VAC and 6.7A at 240VAC.
Altho the saw ran fine on 120VAC, and I was only loading the circuit to about a maximum of 65% of the recommended 80% circuit capacity, I did not like loading the 120V/20A circuit I was using to that level. Since I had provided multiple 240VAC circuits when I built the shop, I decided to switch the motor over to a dedicated circuit at the higher input voltage.
This changeover does not save any money, contrary to many of the misguided rumors floating about, because the electric bill is based upon the number of KWH used. Doubling the input voltage usually produces a corresponding reduction of around 50% in the amperage required. The main benefit is balancing the amperage draw across both sides of the incoming line, with each line only drawing half of the current. So the bottom line is that instead of one side of the line on a 120VAC circuit drawing a full 13A, each side of a 240VAC circuit is only drawing about 6.5A. In addition to changing the motor wiring connections, I did have to change the motor plug to a NEMA 6-20 plug to accommodate the 240VAC circuit receptacle.
The one change that I did notice after changing the input voltage to 240VAC was that the motor spins up to full operating speed almost instantly —noticeably faster than when it was running on 120VAC, even tho it didn’t seem to be especially slow before.
Well folks, this chapter ends the discussion of the modifications I made to my beloved Model R4511. I hope the information in this blog has been not only interesting, but useful to some of you, especially to fellow owners of this marvelous machine. If nothing else, it has served to document this journey for me, so that I might have it to share with other woodworkers in the future. I do plan to post this project here on LJ, as well as some of the other woodworking forums with a link back to this blog.
That said, please return one more time for ………………The Unveiling — Before and After…………….!
‘Til then, I wish all of you a Happy New Year! May you be blessed with good health, prosperity, a safe time in your shops, and maybe some new toys!
-- Paul, Auburn, WA