LN 140 Plane - How Useful?

[Harbo]

I attended Rob Cosman's demo on Dovetailing yesterday at Westonbirt .
To assist in making out the pins he cut a very shallow rebate using a LN 140 skew plane which is a very nice dodge?
It looked like a nice tool, but how useful for other uses - it seems a bit of a luxury to have just for cutting dovetails? I suppose it cuts cross grain without the need for a spur? Shoulder plane might do it but it has no fences?

Rod

PS - Rob stated that their is a new LN DT saw coming out soon to Rob's specification?

 

[paulm]

I was thinking about the same thing Rod and was going to try a shoulder plane or rebating block plane together with a guide strip of wood clamped on the workpiece, but I am almost certain that is going to be too much faffing around, and the 140 with fence must be a lot quicker and easier, but interested to hear others thoughts.

The shallow rebate was a nice touch and must help keep the inside corner lines nice and clean as well as helping locate the pieces for marking out.....

Cheers, Paul

 

[woodbloke]

I attended Rob Cosman's demo on Dovetailing yesterday at Westonbirt .
To assist in making out the pins he cut a very shallow rebate using a LN 140 skew plane

Rod - now you've got me intrigued...why? - Rob

 

[paulm]

It was a very simple idea Rob but sounds like a good idea to the untrained amateur like me :lol:

Would be interesting to get your own view.

He just takes a couple of shavings off the inside of the end of the tail board (to the same width as the pin board) before cutting the tails.

Then when positioning the tail board on top of the pin board to mark the pins out, the small lip of the rebate is used to get exactly the right alignment of tails on pin board prior to marking.

Also I imagine gives a slightly increased chance of the inside corner looking good when done.

Think I've explained that right but I'm sure someone else will chip in if I've got it round my neck !

May not be necessary for an experienced craftsman perhaps but I suspect might be a help to the amatuer like me :lol:

What do you think ?

Cheers, Paul

 

[Harbo]

Rob - it's like Chisel said to help locate the tails and pin pieces for marking out.

He took a couple of thin shavings from the "inside side" of the tail piece across the tails - leaving a tiny reference edge (rebate) - cutting up to his scribed line.
He then placed the pin piece in the vice vertically, protruding to the height of his plane width ie he used his plane (LN 5.5?) on it's side as a guide. Then moved it away slightly and rested the tail piece on top with the rebate down, against the pins ensuring a perfect fit/alignment - the tail wood is then horizontal and the rebate locates the edges. He ensured that what would be the bottom edges of the pieces were aligned (with a straight edge), held the tail piece in position with one hand and marked with a knife the pins. Very quick and no clamps used (apart from the vice). The rebate keeps everything lined up.

Hope you could understand - much easier to demonstrate than to explain?
I bought his "Shop Copy" book to remind me.

Rod

 

[Derek Cohen (Perth Oz)]

It looked like a nice tool, but how useful for other uses

Rod

It is the plane for tenon faces.

Regards from Perth

Derek

 

[custard]

It looked like a nice tool, but how useful for other uses - it seems a bit of a luxury to have just for cutting dovetails? I suppose it cuts cross grain without the need for a spur? Shoulder plane might do it but it has no fences?

I recently got one, hoping to replace a range of hand tools in my travelling toolbox.

Early days yet but my early reaction is only so-so. For rebating the LN 140 fence isn't as stable as the fence on the Record 778, but the cross grain spur nicker on the LN 140 does a cleaner job than the Record 778.

Using the LN 140 as a shoulder plane with the side plate removed and it's obvious that the front sole on the LN140 just isn't as stable as the front sole on a large LV shoulder plane. When used as a low angle block plane it's a sweet tool, but it is quite a bit heavier than all the other block planes I normally use.

 

[woodbloke]

It was a very simple idea Rob but sounds like a good idea to the untrained amateur like me :lol:

Would be interesting to get your own view.

He just takes a couple of shavings off the inside of the end of the tail board (to the same width as the pin board) before cutting the tails.

Then when positioning the tail board on top of the pin board to mark the pins out, the small lip of the rebate is used to get exactly the right alignment of tails on pin board prior to marking.

Also I imagine gives a slightly increased chance of the inside corner looking good when done.

Think I've explained that right but I'm sure someone else will chip in if I've got it round my neck !

May not be necessary for an experienced craftsman perhaps but I suspect might be a help to the amatuer like me :lol:

What do you think ?

Cheers, Paul

Interesting...I've never heard of that one before, though I'm sure it would work. I use a plane on the side (Norris A1 panel plane here, none of your LN rubbish :lol: ) and just use a square to make sure everything's aligned properly. In fact the tail board should be very slightly in front of the face of the pin board to ensure the pins pull up to the bottom of the socket, if they're on the line, there's usually a gap at the shoulder or bottom of the pin when the joint is fitted, 'specially when you start to clean up the inside faces prior to gluing.
No question that RC does cut some nice d/t's, but the stuff he uses for the tail board is a very soft, easily compressible timber (soft maple of some sort?) easily dented by my finger nail at Westonbirt yesterday.
I think if both bits of timber were truly hard, a different techinque might be on offer from RC - Rob

 

[Harbo]

Rob - if that was the joint Rob C made in the morning it was from Aspen and American Cherry.
Rob likes to use a pale and dark wood combination to emphasise the "handmade" DT. He also uses a LN chisel ground to 17degrees to prevent the fibres being crushed and pulled out.
I am pretty sure he uses the same technique whatever the woods used - he said you have to be even more precise in cutting with the harder woods as you will not get any compression benefits.
I know that David C uses a right angled support with cramps for marking out the pins. David C chisels out the waste. Rob C (like Robert Ingram) uses a coping saw to remove the bulk (to within 1/32" of the line) and then trims with a chisel. Rob C reckons that removing most of the wood accurately first time saves a lot of time in the overall process.
Rob C stated that anybody with the correct tools following his method would achieve a very good joint - on a percentage basis, practice only amounted to a 10% improvement?
He used a very small spatula for gluing and there was very little clean up to be done. He planed up the sides and edges whilst the glue was still wet so the joints were pretty tight?
Oh and he does not camber his plane irons.


Rod

 

[woodbloke]

Thinking about this a little more, the way to avoid cleaning up too much is to gauge the tail board shoulder line a fraction thinner ( say .25mm) than the thickness of the wood and then when the pins are marked the outside faces are brought flush (has the same effect as overhanging the tail board) This is a technique that Robert Ingham uses to good effect and it works very well.
I use a piercing saw to remove most of the waste to within about 1mm of the line and then chisel down to it.
The use of aspen (or similar) at Wesonbirt makes it easier for RC to get a good fit first time because of the mushiness of the timber...if he used rock maple for each part of the joint then I reckon the demo would be a lot longer than it actually takes - Rob

 

[Imperial]

Nice article here from a few weeks back with pic's, wonder where this idea came from 1st?

http://www.woodworking-magazine.com/blo ... tails.aspx

I also find that cutting dovetails by hand is down to being dextrous rather than the tools used. I've seen "good" joints cut with a jigsaw.Practise helps refine, but finding a technique which suits you is most important. Some people will just never get it not matter what DVD or demo they watch, but may be able to set up a jig with a router and get them to fit perfect everytime! It's more important to enjoy what your doing and not to get hung up on perfect fit, IMHO.

 

[woodbloke]

Nice article here from a few weeks back with pic's, wonder where this idea came from 1st?

http://www.woodworking-magazine.com/blo ... tails.aspx

I also find that cutting dovetails by hand is down to being dextrous rather than the tools used. I've seen "good" joints cut with a jigsaw.Practise helps refine, but finding a technique which suits you is most important. Some people will just never get it not matter what DVD or demo they watch, but may be able to set up a jig with a router and get them to fit perfect everytime! It's more important to enjoy what your doing and not to get hung up on perfect fit, IMHO.

Having had a quick look at that site, in my view it's not one to be recommended for a 'how to' on cutting d/t's...the pics are instantly off putting as pins are too wide and tails at far too much of a rake.
Agree that you must enjoy what you're doing (not much point otherwise) but most of us (me included) are always seeking ways of making our woodwork better. Perfection will never be achieved but we can strive for precision, which is :wink: - Rob

 

[Imperial]

Rob, don't understand what's instantly off putting about the pic's or the rest of the article. Sure tiny pins look better but are you saying that this joint will break easier because the rake is too large? or is it the look you don't like? They seem to be an excellent fit, so no problem with execution of the task.

 

[woodbloke]

Difficult to gauge exactly from the pic but the rake on the tails is far too great, looks about 1:4 or 5. If it's softwood it ought to be 1:6 and hardwood (which I suspect) 1:8. Again, my personal view here but it looks pretty crude to me and not the sort of thing to advertise as a good example of the joint. Whilst I take a little bit of issue with the use of RC's materials (no doubt chosen for ease of use during demos) he does make a very finely proportioned joint which is a pleasure to look at...the one's on the link are not.
As to wether the tails would shear, given sufficient tension d/t's with a rake as shown in softwood will break - Rob

 

[Harbo]

I agree Rob I do not like the look of those DT's.
Rob C stated that his primary aim is to get them looking right and appearance is the most important aspect, also thin pins are impossible by machinery so that's another good reason for doing them. He used a 1in 7 guide and discussed that the half pins should be reasonably close to the ends but not too close that they might break or spread - he went for 1/4" on the 3" piece he was using. For strength the more pins the better but again appearance was paramount - he reckoned 3 was a good choice on that piece.

Rod

 

[woodbloke]

I agree Rob I do not like the look of those DT's.
Rob C stated that his primary aim is to get them looking right and appearance is the most important aspect, also thin pins are impossible by machinery so that's another good reason for doing them. He used a 1in 7 guide and discussed that the half pins should be reasonably close to the ends but not too close that they might break or spread - he went for 1/4" on the 3" piece he was using. For strength the more pins the better but again appearance was paramount - he reckoned 3 was a good choice on that piece.

Rod

Rod - a general 'rule of thumb' is that the half-pin each side ought to be half the thickness of the timber plus a tad, so if he was using 12mm timber then the half-pins each side should have been about 7mm on the shoulder line. D/t spacing is again subjective, but a general rule is one tail per 25mm...ish, so on a 75mm wide board, 3 tails would look good, assuming that your pins in the middle are nice and narrow
Edit - you've got to keep your hand in though. The last time I cut some d/t's was when Paul C came down for the Bash at the end of June and it's taken me:

....three goes :x to get a decent joint in the 'shop just now - Rob

 

[Paul Chapman]

it's taken me:


....three goes :x to get a decent joint in the 'shop just now

That's very comforting for the rest of us, Rob.......

Cheers :wink:

Paul

 

[bugbear]

I know that David C uses a right angled support with cramps for marking out the pins. David C chisels out the waste.

An idea he duly credits to Robert Wearing. I prefer using these, which saves some clamp juggling.

http://www.geocities.com/plybench/tour. ... il_marking

Rob C (like Robert Ingram) uses a coping saw to remove the bulk (to within 1/32" of the line) and then trims with a chisel.

It was a jeweller's (or "piercing") saw last time I saw him. Are you sure he's changed to a coping saw?

BugBear

 

[woodbloke]

Bug Bear wrote:

It was a jeweller's (or "piercing") saw last time I saw him. Are you sure he's changed to a coping saw?

I'm pretty sure you're correct, piercing and not coping saw - Rob

 

[Harbo]

Sorry - Rob C was using a (very shiny) piercing saw.

Rod