Cosman Kerf X-10

[Charles Guest]

People have been tapping assorted bits of thin metal to finish into the corners of lap dovetails since time immemorial. You don't have to finish into the corner this way, but if you do you're in good company. Arguing what to use is like taking a stand on the type of broom used to sweep up at the end of the day. Who really cares?

[Derek Cohen]

...

If you are trying to infer I think Tage Frid was a "dickhead", well I'm not sure how you managed that leap. See paragraph two as to why I chose to respond.

Graham, that is the very opposite of what I stated! I think Tage Frid was a wonderful teacher and appeared to used tools in a flexible and innovative manner. Read what I wrote again.

Regards from Perth

Derek

[Bob Jones 5443]

Jim K., thanks for the idea of the third (diagonal) cut in the middle of the waste between the pins. This is a zero-stakes cut and it sounds like a victory tap on a 2” putt. Brilliant.

[Graham Haydon]

You made quite clear your respect for him. Your inference was that how dare I question a method, which I didn't, and then went on to add in that because I don't use the method I must somehow think another person is a "dickhead".
I questioned the logic of people thinking, in this case you, were inventors of a unique tool. Congrats, you think you were the first person you know of to make a kerfing tool. Do you have any more methods or tools that you feel you invented?

[Bob Jones 5443]

We sometimes find that words put into writing, however tongue in cheek, have an unintended way of screaming to the reader. Maybe a moment to let this one go?

[Bob Jones 5443]

Bob, your are correct it will make paring go quicker. If you also make a cut in the center of the pin the waste can be popped out quickley.

If you check > https://sawmillcreek.org/showthread.php?258465 < scroll down to post #18 to see my use of a kerf cutter.

Having a special tool for this can be pleasing. Using what is already in the shop, "free scraper blade," is thrifty.

jtk

Jim, now I've read through your tagged post and seen you in action with the Bontz kerf cutter, and also the mid-waste cuts in the pin board. Nice.

Can't remember if I've already said this here, but my big challenge is going to be sawing square. I further like your idea of cutting two tail boards at once –– seems like it might help keep things square to the face.

[Derek Cohen]

Hi Bob, if your challenge is to saw square - which is the issue when sawing tails-first - then I suggest that you mark the cross lines with a knife, and not a pencil. Score the line deeply, and use the kerf to guide the teeth of the saw. There is even a kerf cutter (scraper) sold by Tite Mark for this purpose. A deeply knifed line has the same effect.

If you are using a fretsaw to remove waste from the tails, then a centre (third) saw cut is unnecessary. I recommend using a fretsaw to remove waste from both tails and pins.

Regards from Perth

Derek

[Derek Cohen]

You made quite clear your respect for him. Your inference was that how dare I question a method, which I didn't, and then went on to add in that because I don't use the method I must somehow think another person is a "dickhead".
I questioned the logic of people thinking, in this case you, were inventors of a unique tool. Congrats, you think you were the first person you know of to make a kerfing tool. Do you have any more methods or tools that you feel you invented?

Graham, you have completely misread what I wrote.

Your comment was to the effect - as I read you - that I was calling Tage Frid a dickhead. I simply stated that I had not, and that you should read what I wrote again ... to recognise the double negative. I have known you a long time, and we have been cyber friends in this time, and I have never insulted you before. Why would I start now?

Regards from Perth

Derek

[Bob Jones 5443]

Hi Bob, if your challenge is to saw square - which is the issue when sawing tails-first - then I suggest that you mark the cross lines with a knife, and not a pencil. Score the line deeply, and use the kerf to guide the teeth of the saw. There is even a kerf cutter (scraper) sold by Tite Mark for this purpose. A deeply knifed line has the same effect.

If you are using a fretsaw to remove waste from the tails, then a centre (third) saw cut is unnecessary. I recommend using a fretsaw to remove waste from both tails and pins.

Regards from Perth

Derek

Thanks, Derek. I've ordered Cosman's marking knife, which has teeth and set to match his saw. Upper photo:



I expect to use it to mark out the pinboard from the tails before chopping out the tail waste (Cosman's method). For starting the tails, I'm wondering if his knife would give me the same result as the Tite-Mark kerf starter you suggested. It's hard to discern how the Tite-Mark is built, the photos are so small on the website. This copy of the photo suggests teeth, but I think it's only pixelation:




The description says it "looks like a knife but works like a scraper," and says it takes a "shaving the same way other scrapers remove shavings." It talks about using a flat burnisher to keep it sharp. So based on the brief text description, it does NOT seem to be similar to Cosman's marking knife with the saw teeth. Do you have this tool? Can you describe how it's built and how it works for you?

[Derek Cohen]

Bob, I do have a Kerf Starter. It, along with the joinery saw, was sent to me for a review in 2012. http://www.inthewoodshop.com/ToolRev...oinerySaw.html

Here is an extract ...





I like the way this tool created a clean kerf for the saw. I can see it being particularly useful for beginners and advanced users alike.


Here is the marked edge, now ready for sawing.







I am not sure whether Kevin would advocate scoring the diagonal lines with the kerf starter or not. I chose to pencil them in, as is my usual method.









I think the Kerf Starter is an excellent tool. It should work similarly to Cosmon's sawtooth knife, but I expect it to more controllable when marking out in hard woods (no teeth to wander in the grain). I occasionally use it, and then marvel at how useful it is.

Regards from Perth

Derek

[Graham Haydon]

"I can say, with some confidence, that I made the first dedicated kerfing tool. This was in 2011 - certainly long before Cosman ..."

This was the point I was commeting on, not the method. It's a bold statement and made me roll my eyes.

The separate issue is I don't have to find value or agree with your methods. This does not diminish you or me.
There are too many ways to do a job, you favour your approach as do many others.

Highlighting a highly skilled woodworker and pointing out he used a version of the method and he was not a DH was not needed. I could do the same, but we're all smart enough to try something and review it's effectiveness in our setting. For me it did not help get your point over. Plenty of other people don't use the method and aren't a DH. At best there is lost humour here, at worst a veiled put down.

I enjoy seeing your work and respect your approach and I look forward to more in the future.

[Charles Guest]

Isn't an old section of saw blade, or a scraper converted for the task a "dedicated" tool? Everything doesn't have to have a handle on it. Sometimes it's best they don't.

Here's something for fans of less exposed joinery. In the 18th century piece below, the rather famous woodworker likely from a renowned family of cabinet makers covered dovetails with what amounts to a thick veneer. Some might find this liberating, others may think "well, if I can't display my hard earned joint-making skills, then what?" How about a toast to beautiful overall proportions, tasteful and subdued surface ornamentation impeccably wrought, perfectly proportioned and executed legs, all way more difficult to achieve (on the fly, with a living at stake, and employees to pay!) than a snug dovetail. Nice bit of narrative as well about the division of labor. Working against the clock and a hungry stomach puts a different gloss on things. To pull off now recognized works of art under those pressures was quite a feat, and you were only as good as the last piece that went out the door with the invoice paid in full.

With regard to more modern tastes and fashion, when Krenov didn't want joinery to spoil the look and flow of grain and color of the wood he simply used dowels. He didn't need to endlessly impress himself with an ability to cut dovetail joints. I think when you're able to opt for a simpler joint, to get out of the way of the design and the material, then a milestone will have been reached. Pieces just smothered in exposed joinery just don't do it for me personally, but that's why they make chocolate and vanilla too. I've seen beautiful work posted on this forum that I think would have looked infinitely better had joints not been of the exposed type. Infinitely better. That's a tough design decision to make when you seemingly need continuous reassurance from others that you're a competent craftsman. The crowd that will cheer-lead a well cut dovetail joint is far larger than the crowd that will cheer-lead a design decision to forgo them altogether, or subdue them in some other manner.

https://www.youtube.com/watch?v=8pASdFYNPIk&list=PL71EFD735F41533E7&index= 1&t=86s&ab_channel=NewportRestorationFoundation

Jeffrey Greene: https://jeffreygreenenewport.com/

[Derek Cohen]

"I can say, with some confidence, that I made the first dedicated kerfing tool. This was in 2011 - certainly long before Cosman ..."

This was the point I was commeting on, not the method. It's a bold statement and made me roll my eyes.

The separate issue is I don't have to find value or agree with your methods. This does not diminish you or me.
There are too many ways to do a job, you favour your approach as do many others.

Highlighting a highly skilled woodworker and pointing out he used a version of the method and he was not a DH was not needed. I could do the same, but we're all smart enough to try something and review it's effectiveness in our setting. For me it did not help get your point over. Plenty of other people don't use the method and aren't a DH. At best there is lost humour here, at worst a veiled put down.

I enjoy seeing your work and respect your approach and I look forward to more in the future.

Graham, I think that we are separated by different versions of English - the average Aussie would have realised that I was paying a compliment (not making a criticism). I think that we should drop the subject.

Regards from Perth

Derek

[Graham Haydon]

Charles, you have hit on the point I was trying to convey.
I have a triangular piece of wood with a sharp screw set in it. It belonged to my Great Grandfather and would of been made and used anytime from 1909 onwards. It's his take on a scratch tool. I've not seen a triangular one before. Funnily it was never named the GSH scratch stock. It was simply a shop made tool, a version of millions of other scratch tools that went before.

But I'll book mark this page. If I see another tool that looks like it I'll make sure to make a point of saying, "that's cool, I use something similar." I won't add that he my made the first documented triangular profile version. It would be a baseless and pointless comment. To think your the first to do something in woodworking is beyond rare.

[Derek Cohen]

OK, I get it now ... why if it is not one issue, it is another.

I checked out past posts. Graham, you just visit SMC to heckle. You do not offer solutions, only fault-finding and criticism. You must be very bored, angry or both.

Regards from Perth

Derek