woodbloke
Established Member
I've used a variety of knives shown below in the pic to mark out pins from tails - none have been really satisfactory
The small stanley knife has a very pointy profile so that its quite difficult to register it against the side of the tail, added to that it has a double bevel on the blade, so it has to be canted to one side to make it snug at the bottom of the dovetail. The scalpel is similar but worse, its too flimsy and makes such a faint line that its difficult to see it at all. I tried a Jap knife which I backed of on the grinder so that it could mark both sides of the tail; same sort of problem as the other two tho' in addition the hollow grinding on the back of the blade further restricts the accuracy as there's less steel to sit against the tail
Then..... I remembered that lurking in my odds n' sodds box I had a small piece of HSS hacksaw blade so I made a knife as shown; 10 minutes on the grinder.
Its double ended and ground only on one bevel each end so that each side of the tail can be accurately marked. It isn't pointy like the other ones so there is plenty of metal to rest against the side of the tail.....however it is a little bit flexible in use and a trifle small in the hand so then I had some further thoughts and remembered that in the deepest and darkest recesses of the aforementioned box I has a piece of HSS machine hacksaw blade....so I made yet another knife
Again, about 10 mins on the grinder and because its HSS I didn't have too worry unduly about losing the temper on the steel - didn't get it too hot tho'. This one works superbly, ground again only on one bevel at each end and the thickness of the steel means that it don't flex at all.
Its probably worth IMO doing a trawl round your local friendly machine shops to see if you can scrounge some broken machine hacksaw blades because they do make excellent knives. I once worked with a Parnham trained maker who used nothing else as a marking knife having tried all sorts of others; he also used a knife like this to cut veneer using a square block of timber to rest the blade against. Pics a little out of focus, hope explanation helps - Rob
The small stanley knife has a very pointy profile so that its quite difficult to register it against the side of the tail, added to that it has a double bevel on the blade, so it has to be canted to one side to make it snug at the bottom of the dovetail. The scalpel is similar but worse, its too flimsy and makes such a faint line that its difficult to see it at all. I tried a Jap knife which I backed of on the grinder so that it could mark both sides of the tail; same sort of problem as the other two tho' in addition the hollow grinding on the back of the blade further restricts the accuracy as there's less steel to sit against the tail
Then..... I remembered that lurking in my odds n' sodds box I had a small piece of HSS hacksaw blade so I made a knife as shown; 10 minutes on the grinder.
Its double ended and ground only on one bevel each end so that each side of the tail can be accurately marked. It isn't pointy like the other ones so there is plenty of metal to rest against the side of the tail.....however it is a little bit flexible in use and a trifle small in the hand so then I had some further thoughts and remembered that in the deepest and darkest recesses of the aforementioned box I has a piece of HSS machine hacksaw blade....so I made yet another knife
Again, about 10 mins on the grinder and because its HSS I didn't have too worry unduly about losing the temper on the steel - didn't get it too hot tho'. This one works superbly, ground again only on one bevel at each end and the thickness of the steel means that it don't flex at all.
Its probably worth IMO doing a trawl round your local friendly machine shops to see if you can scrounge some broken machine hacksaw blades because they do make excellent knives. I once worked with a Parnham trained maker who used nothing else as a marking knife having tried all sorts of others; he also used a knife like this to cut veneer using a square block of timber to rest the blade against. Pics a little out of focus, hope explanation helps - Rob
My problem is I like a point that points downwards (like the top one in your pic of three, Rob), which rules out all the gorgeous spear point varieties like Derek's. Making do with a CK lamb's foot at the mo', but the double bevel isn't ideal and it's a bit chunky for finer pins. Oh well, at least it's a reasonably inexpensive quest to keep me out of mischief :lol:
