Thread: Making Hand Saws

On the subject of making knives from salvaged hardpoint saws, I wonder about hardening 1/2" at the edge with an oxy acetlene torch before grinding the bevel. It could be done pretty quickly and if it would air quench i bet there would be little warp.

Originally Posted by bridger

On the subject of making knives from salvaged hardpoint saws, I wonder about hardening 1/2" at the edge with an oxy acetlene torch before grinding the bevel. It could be done pretty quickly and if it would air quench i bet there would be little warp.

Depending on the style of knife that may well work. However it works because the plate is only 1 mm thick, which is why I am making the filleting knife pictured in an earlier post. Most knives would need much thicker steel. It is 1/2" wide along the length of the blade s in this case that would be a full heat treat.

What style of knife were you thinking of to do this, Bridger?

The carbide tip drill bits you want are called multi-purpose drill bits.
They look like masonry bits but are a little more refined and not used with the hammer setting.
Still a bit blunt. You may be able to sharpen them with a diamond plate.

Bunnings stock Kango brand.
Kango 4 x 105mm 1/4" Hex Multi Purpose Drill Bit | Bunnings Warehouse
Bosch also make them and have the light blue paint in the grooves.
Bosch 4-8mm TCT Multi-Purpose Drill Set - Multiconstruction - 4 Piece | Total Tools
Both made in Germany I believe.

However, these work better:
Blackburn Tools - Solid carbide spade drill bits
Available locally here:
Hand Saw Maintenance : Drill, Spear Point, Blackburn Tools, Solid Carbide, 3/16 inch (4.76mm)

These are even quicker:
P108 - P6 Hand Punch | Hare & Forbes Machineryhouse

You beat me to the punch, HR. I had to get some stuff from the big green shed yesterday and spent several minutes perusing the drill section. They don't stock Bosch at the branch where I was (sorry, Doug, my ageing memory let us down, it was indeed Bosch who make the blue-fluted ones. ) but they did have the Kanga multi-purpose bits you mention. These only seem to come with hex-tops, whereas the Bosch are plain bits. Anyway, out of curiosity, I grabbed a 5mm Kanga & I'll put it to the test later & let you know what I think.

The solid-carbide bits are more efficient at drilling thin plate, & their sharper points are easier to place accurately, but only seem to come in Imperial sizes. 3/16" is close to 5mm, but a 5mm bolt won't go through a 3/16 hole without some reaming.

Cheers,

Originally Posted by doug3030

Depending on the style of knife that may well work. However it works because the plate is only 1 mm thick, which is why I am making the filleting knife pictured in an earlier post. Most knives would need much thicker steel. It is 1/2" wide along the length of the blade s in this case that would be a full heat treat.

What style of knife were you thinking of to do this, Bridger?

For my purposes a marking knife or two, perhaps something like those chip carving knives. How about a curved spoon carving hook knife?

- - - Updated - - -

Originally Posted by doug3030

Depending on the style of knife that may well work. However it works because the plate is only 1 mm thick, which is why I am making the filleting knife pictured in an earlier post. Most knives would need much thicker steel. It is 1/2" wide along the length of the blade s in this case that would be a full heat treat.

What style of knife were you thinking of to do this, Bridger?

For my purposes a marking knife or two, perhaps something like those chip carving knives. How about a curved spoon carving hook knife?

Originally Posted by bridger

How about a curved spoon carving hook knife?

I have never done any spoon carving but my gut feeling is that you would want more than 1 mm of steel.

If you want to make it out of recycled material, I would try a plow harrow (usually very much like 1084) or even a car leaf spring.

Here's a list of what steels can often be found.

Note that this information is not definitive. Manufacturers will often cut costs by using inferior materials. This is just a guide.

junkyard steel.jpg

Righteo Doug, here's a quick 'review of the Kango 'multipurpose' drill.

This is what you are looking for when you go to the big shed: Kango drill.jpg

It has the same set of symbols on it as the Bosch drills mentioned earlier, and the astute observer will recognise that the only difference between this and the same brand's masonary drills is the additional I-beam symbol indicating it's ok for drilling metal.

My heart sank a little when I saw stamped on the shank of the bit "5mm/3/16". What the heck does that mean? Three sixteenths of an inch may substitute for 5mm in some situations, but a 3/16 hole in metal will not pass a 5mm bolt under normal circumstances!

I popped it in the DP & drilled a few holes in an old hard-point blade (which I measured at a teeny bit less than 1mm thick). The good & bad news is that the bit went through the saw blade ok, but there was so much run-out that the resulting holes left a broad ring of daylight around a 5mm bolt. sawplate holes.jpg

I discovered with the Bosch drills that using cutting fluid is a bad idea - it seems to stop them cutting properly & they rapidly self-destruct, so I just used it dry. The steel peeled off in satisfying spirals which were pretty hot & blued, but that doesn't bother carbide, which can stand far higher operating temperatures than HSS.

I took a more critical look at the bit & decided that the shaft was well-machined & likely to be concentric, so I pulled out the angle grinder & whacked the hex section off. I also used a diamond file to touch up the cutting edges. Cutting off the hex top (& shortening it) reduced the runout and sharpening it made it cut better, & the next hole I drilled was a much neater fit for my test-bolt.

So there you go - a not too expensive & easy way to make holes for your knife handle rivets...
Cheers,

Originally Posted by IanW

Righteo Doug, here's a quick 'review of the Kango 'multipurpose' drill.

Thanks Ian.

A well written and comprehensive writeup for sure.

I haven't tried my Chinese Carbide set yet, but if that fails Kangas will be next.

I have seen some good reports on blade forums about Kangas. Pretty much the same problems you identified with runout and they recommend wd40 instead of cutting fluid.

As I said earlier I will write up a review of the chinese carbide when I get a chance to check them out. Tungsten Carbide Drill Bit Set for Porcelain Ceramic Tile Concrete Brick Glass | eBay

I'd be surprised if those drills don't do the job for you, Doug. The only caution I would have drilling thin plate with one is to make sure the plate is held down firmly so the edge of the carbide spear-point doesn't catch as you feed it in & tear a jagged hole.

They aren't the sort of thing you'd go to for extreme accuracy, but should do an adequate job for your purposes, all you need is a hole in the plate to get the rivet though. Peening the rivets should squash them out & fill the hole a bit, unless it's really over-size. In any case, if I were applying scales to a knife that is going to be in a wet environment like a filleting knife will be, I'd use a water-resistant epoxy between scales & metal as well to keep moisture out.

Cheers,

I use epoxy glue and cutlers rivets to hold the scales to the knife.

Regards
Paul

Originally Posted by IanW

I'd be surprised if those drills don't do the job for you, Doug. The only caution I would have drilling thin plate with one is to make sure the plate is held down firmly so the edge of the carbide spear-point doesn't catch as you feed it in & tear a jagged hole.

They aren't the sort of thing you'd go to for extreme accuracy, but should do an adequate job for your purposes, all you need is a hole in the plate to get the rivet though. Peening the rivets should squash them out & fill the hole a bit, unless it's really over-size. In any case, if I were applying scales to a knife that is going to be in a wet environment like a filleting knife will be, I'd use a water-resistant epoxy between scales & metal as well to keep moisture out.

Cheers,

Well I will find out soon enough.The blade will be well secured to the drill press. Last thing we need is a blade flapping around a drill

5 minute epoxy is what most people use, but if I have time to let it set which I will, then full strength epoxy will do nicely.

Rivets are one way to secure the handle but another is Corby Bolts - kind of like a skinny sawnut.

Seeing as how I make my own sawnuts I was thinking of making up a set of Corby bolts and giving that a try.

YouTube

Doug

That looks very tidy, but rather protracted. I do however like the ability to finish so flush after cutting off the excess of the Corby bolt.

I glue one scale on first without holes. Then you drill through from the blade side and this automatically gives the guide to drill out the the holes in the second scale after that is glued up. I gently tap the cutlers rivets in place just to engage the two parts but bring them together by placing them in the engineers vice. Once you glue the scale on with epoxy the mechanical fasteners are purely cosmetic. You could just insert small discs of metal to look like rivets.

I don't think I would use the five minute stuff with the Corby fasteners.

Regards
Paul

Paul I did not see your previous post about the Cutlers rivets until just now - you would have posted it while I was writing my previous post.

Originally Posted by Bushmiller

That looks very tidy, but rather protracted. I do however like the ability to finish so flush after cutting off the excess of the Corby bolt.

I have never used Corby bolts before, and I just want to experiment with them. In fact I have only made hidden tang knives so far, the filleting knife will be my first full-tang. My mentor does not use COrby Bolts because he only makes hidden tang knives. Some makers do use Corbys in hidden tang knives but I see no point myself. In a full-tang construction Corbys eliminate the need for the vise and/or clamps

Originally Posted by Bushmiller

I glue one scale on first without holes. Then you drill through from the blade side and this automatically gives the guide to drill out the the holes in the second scale after that is glued up. I gently tap the cutlers rivets in place just to engage the two parts but bring them together by placing them in the engineers vice. Once you glue the scale on with epoxy the mechanical fasteners are purely cosmetic. You could just insert small discs of metal to look like rivets.

In a full-tang construction Corbys eliminate the need for the vise and/or clamps in the glue-up. There's so many different ways you can go to align the scales and secure them. At this stage of my my knifemaking journey I am just experimenting and finding my way. Of course some things work with some styles and not with others and it's always great to have options.

Originally Posted by Bushmiller

I don't think I would use the five minute stuff with the Corby fasteners.

Probably not needed on a filleting knife, but on a utility knife with a hard-working future ahead of it, I would recommend it.If all you are relying upon to hold the scales to the blade are the pins - corbys or rivets - and the timber scales split along the grain they will not stay on long.