Part two of the Gents Saw Conversion series. This may be a bit verbose, so I apologize ahead of time. After all, we are just drilling holes…
The next step in the conversion process is drilling holes. A lot of holes. You will need a variety of forstner and twist drill bits to complete these steps.
With your template affixed to your stock, use an awl to create reference points on all of the indicated locations, or use the spur on the forstner to create a divot. Apply moderate pressure so there is a positive location for the bit to enter when the drill press is in operation.
The Gramercy pattern that I am using indicates the center point and diameter of the hole for the tote and split nuts. We will focus on hogging out the holes that give the tote its shape first. These holes will be used to create the stunning curves that are found in traditional western back saws.
Before you drill your first hole, you will want to back up your stock with a fresh piece of plywood on the drill press to make sure you minimize any tear out.
Make sure you drill out all of the holes with the appropriate bit. This particular pattern uses three different forstner bits and one twist bit for the shape of the body alone. It can be easy to be complacent and drill the wrong diameter hole.
Next up, we need to drill for the split nuts. The saw template by Gramercy suggests using a 1/8th inch drill bit to act as a thru / pilot hole for the two split nuts and then drill out the large recess for the heads of the nut, following up with the appropriate bit for the shaft. The smaller diameter through-hole serves to perfectly align your bits on both sides of the saw tote.
We are left with something that sort of resembles Swiss cheese.
At this point you can take the stock to the band saw to rough out the handle shape. Alternatively, you can also use a coping saw or scroll saw or any other method that suits your fancy / tool collection.
You may be tempted to start shaping the tote right off the band saw, but don’t do it until you have completed all of the steps below. Drilling out the tote to receive the hardware requires some precision to ensure you have a tight fitting saw that is perfectly square and parallel when finished. If you make a big error, you may end up throwing the tote away and having the start from scratch.
Mark a center line where the tote will receive the mortise of the folded back and where the saw plate fits inside the body. You could use a pencil, but a marking knife gets better results.
A marking knife line provides a positive stop for an awl or drill bits. Take a sharp marking awl and make 4-5 dimples for your drill bits along the center line you created, leaving just enough space between each dimple that your drill bit will overlap about halfway into the next hole.
If you don’t add these divots, your bits may wander, causing a misshapen mortise. Don’t ask me how I know this…Pay no attention to the kingwood inlay.
Select a drill bit that is the same width as the folded back, or ever-so-slightly larger. You could also drill it slightly narrower, and clean up with chisels if you prefer. Your goal is to get a clean, slip fit. Depending on your finishing process, a piston tight fit in the rough state might make assembly much much much harder in the end. I go for 1/64th over in most of my hardware drilling operations.
Set your depth stop on the drill press so that you are making the same depth hole each time. I set mine so that the folded back will stick up above the tote by about 3/16”. This is personal preference.
Take your time to hog out the waist, clearing the chips and checking your progress. You want to drill every other hole you marked with the awl, and then come back and drill out the remaining waste. Clean it up with a sharp chisel, or small file. This yields better results. Check to make sure your saw back fits.
Next up, we need to drill for the split nuts. The split nuts you have on hand dictates the drill bits you will use. I am using 7/16” brass split nuts from Alamo Saw Works. The template I am using calls for 1/2” split nuts, but I am a rebel. I live on the edge and through caution to the breeze. Its what I had on had, folks.
The 7/16” split nuts are advertised as “small split nuts”. They are probably the least expensive brass split nuts you can buy, especially if you buy more than 6 at a time from Alamo. The quality to price ratio is quite good.
I opt for a very slightly larger hole, so I use the 29/64” bit so I have wiggle room that you cant really see with your eye. I lower the bit on my work piece so the cutting section is fully engaged while the drill is off, and set the depth stop to the width of the split nut + a hair (like you would with a plunge router). The paper width difference helps you to sand the handle flush with the saw nuts later. I find it easier to remove a very thin layer of wood than removing the brass. Plus, brass dust can embed itself in your tote and stain lighter colored woods.
Once the larger mortises are drilled out on both sides of the tote, you may have to drill a secondary mortise just below the head of the split nut. Some manufacturers like TGIAG and Winsor saw have square shoulders in this area. You can pre-drill and use a chisel to cut out the square shoulder. This design is traditional and keeps the bolt from spinning as you tighten the nut on the other side of the tote.
Alamo Saws uses round shoulders, and I keep them this way. I haven’t had issues with them spinning during tightening.
If I wanted, I could add a star washer between the bolt and the tote…
Or file the shoulders square before drilling out the tote. Just make sure that if you take either of these approaches with a round shouldered split nut, you need to account for either the height difference on the split nut, or the change in diameter of the shoulder.
Next, drill out the through hole for the bolt to pass through. Check to make sure your split nuts fit and that the head of the bolt and the nut can be fully seated in the mortise. Be careful not to mar the brass nuts with your driver. Split nuts are very fragile and will ding easily. Having an ever-so-slightly larger hole for the nut will allow you to use your finger to tighten and loosen the split nuts to check the fit.
These split nuts are sitting just below the surface of the wood. Perfect!
Finally, it’s time to cut the slot into the handle for the saw plate. There are so many ways to do this, it comes down to tools and preference. I have chucked up a .020 slitting saw into the drill press, aligning the center line mark on the tote with the center of the slitting saw. NOTE: Before you turn on the drill press, check the feed direction of the saw blade. You will also want to turn the speed way down and take shallow passes. I mount my tote to a piece of plywood to assist with handling and to keep my fingers away from a spinning blade. Essentially, I am using this tool to cut a perfectly fitting and square starting slot for the saw plate that is about 3/8” deep. I do not attempt to get the full depth of cut from the slitting saw because it can be awkward to maneuver the tote. So you can see this is purely an optional tool.
Once you score the tote for the saw plate, you can use a dovetail saw to finish cutting the slot to full depth.
Here I am using a dovetail saw with a .020 thick plate that has almost no set to the teeth. Set the saw in the marking gauge line you made earlier, or follow the pencil line. If you don’t have a spare saw hanging around, use the same gents saw you are creating a new handle for. You can put it back together if you want to hold onto the saw to cut it while the tote is in the vice.
Alternatively, you can also take the saw plate and clamp the blade on a board that is half the thickness of the tote and slide the tote back and forth to achieve a parallel / square cut.
If there is any set to the saw teeth you are using, you will end up with a slightly wider kerf for the saw plate to fit into. Something to keep in mind. The name of the game here is to get a perfectly parallel / square cut that lines up with the mortise for the saw back and provides support to the plate when the tool is fully assembled. Any deviation/twist in your slot will be reflected in your saw plate when you assemble it. A little twist is okay as the saw plate will follow through on the push stroke, but if its significant, it will bind in the cut or make cutting straight lines difficult at best.
The next blog entry will focus on cutting the folded saw back and saw plate, drilling out the split nut holes into the saw plate. We will be using marking tools, a hack saw, tin snips, and a router bit in the drill press.
-- Regards, Norm