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I thought I'd try a Japanese joint!

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RossJarvis:
Now that I’ve made my own toolbox I must be a craftsman, innit!  So as I’ve been threatening, it’s time to get crafty.  I have read a number of books on sawdust and shaving manufacturing including these;



The one on the left is good on history and stuff, with some interesting bits on restoring an old temple, the one in the middle is a bit superfluous but has some nice photographs, The one on the right is very good on a lot of carpentry and joinery and includes lots of very scary joints.

So I thunked “let’s make a splicing joint, with that old oak in the outhouse” I was thinking of a “lapped gooseneck splicing joint” (Koshikake Kama Tsugi?!?), but then decided that might be a step too far, even for yours truly and the “apprentice”.  So I decided on a lapped dovetail.  I’ve done a couple or three of these before and almost got them right, so where’s the problem.  This is called the “Koshikake Ari Tsugi”, not quite sure what the words mean but I presume it’s some relation to ‘Ari Secombe.  There’s two versions of this for a splicing joint, one wot is a fair bit simpler than the other;



The top one is a simple lapped dovetail and the one underneath has a sort of mortice n’ tenony thing in the bottom, so I’m sort of thinking of doing that one.  Hennyway, out to the outhouse and find me some wood;



…here’s a couple of bits of oak wot I got fresh cut and green at Cressington Temple, for a couple of quid about four or five years ago, for some unknown reason they were left-overs;



Could have something to do with the pithy bits (pith?) in them and the odd size.  Anyway I took the pith and stuck it in the outhouse till I could thunk of summat to do with ‘em.  That time has now arrived.  Firstly I thought I might need something a little bit better than the garden staging to plane this on.  Now as luck would have it I noticed a bit of 2x6 that had been hanging around in the porch, hidden behind a Big Austrian and a Little Israeli, dragged it round the back and started to plane an end stop for it;


once again, I resorted to hi-tech bench dogs to hold the planed bit;



Once the stop was square and straight(ish), I thought the planing bench could do with a bit of planing too;



Bish, Bash, Ouch, Bosh, one planing bench with stop;



Nextly I cut a bit of oak off the end of the oak and bunged the rest of the oak back in the outhouse;



I wasn’t 100% sure how the ryoba saw would deal with this wood and it was a bit tricky to start, once I’d stopped using the “rip” side to crosscut and turned it round, it went fine.  It was a little bit slower than cutting pine, but not by much and left a lovely finish.  Next I thought that I’d better get the proper support services in place, as I’d not utilised these well last week;



…just need to keep an eye out for the apprentice to stop him scoffing the lot!    Nextly I started bashing the oak with the plane, having remembered to re-sharpen the iron (and deliberately avoided dropping the sharpening stones on the tiles this time).  It took a fair bit of pushing in comparison to planing pine and there was very little between having the blade below the mouth and skating across the surface and “Oh my good groovy, that’s resisting a bit”.  And the shavings were fairly different too;



…generally quite wrinkly and harder to see through than pine!  I couldn’t find any candles to rub on the plane bottom and couldn’t be ar…bothered to sharpen the no 4 or 4 ½.  It’s some considerable time since I’ve planed oak, so I’m not sure if this is to be expected or not.  Anyway, the surface came out reasonably smooth and almost shiny and with a good stroke of luck I got the edges square;



…and after a few cups of tea, inter-sperced with grunting and iron tweaking we ended up with;



…a lump of oak.  So far it’s looking pretty good, nice flat surfaces, square edges (in a rectangular fashion if you get my drift) and the thin edges are parallel, but the fat ones aint.  The Hampshire monsoon started again so I came back inside to gabble on to you.  Next I want to get the faces parallel, cut the block in half, mark out both joints, throw a saw and some chisels at it and be done, however the BBC says it’ll be sunny all day tomorrow, so I’m digging out my Sou’Wester, but if they’re actually right for once I might be able to get this job done in a day (famous words of the last variety).

AussieJimG:
I'm not much into working with the brown stuff but I love the photos and the commentary so I'll watch for the amusement.

Keep it up and thanks for the entertainment.

Jim

RossJarvis:
Well, once again I over-estimated my abilities or under-estimated time or something, so even though it was sunny(ish), I didn’t finish.  However I did start!  Yesterday I’d nearly got a lump of wood into shape.  Today I managed to get it nearer to shape and cut it in half.  The wood was slightly ramp shaped, so I marked where to plane to;



This was the thick end, and planed, planed, planed.  As I’d now sharpened the blade on the Record No 4 (see my post in the tools section where I’d fixed the broken whetstone), I tried that to see if it was any easier.  The back-iron-chip-breaker-spare-bit-of-metal-thingy was set further from the sharp edge on this as well to see if that made anything easier.  No it wasn’t, so back to the 5 ½ and I got the job done (or so I thought).  Here’s the shavings, if anyone who knows what they’re doing can comment, it would help, is this wot oak should plane like?;




Generally I was very pleased with the finish.  It was smooth, flat and iridescent on the non-holey bits of the grain;





The grain changed direction on one side and even that came up fine;



This is what it looked like before planing;



…and this shows how many shavings have been removed, side view;



…top view;



Once I was happy with it, I marked centre lines down all faces and marked the top (it could have been the bottom, but what’s a top or bottom between friends?;



Then “BONSAI” I attacked it with the saw and cut it in half (why do the Japanese rush into battle shouting ’small trees’?);



By now the “apprentice” was nagging me for some more Hobnobs, so we took a walk to the garage, where I bought some baccy instead.  Whilst he was in a huff we had a scout round for some more hazelnuts, only to realise that the squirrels and field mice have cottoned on to my free food supply, and they’ve scoffed the b****y lot.  After this I had a look through my Japanese Joinery book to check on the dimensions for this joint, found out it didn’t tell me, so I made them up;



If you look closely you can see a bit of a miscockulation!  I generally use an edge for reference when marking out, but apparently the traditional way is to use the centre-line for this sort of thing, so maybe that threw me.  Back out to the “workshop” and time for a bit of ripping;



…the book often suggests a particular order to do this in, but I couldn’t make head nor tail of this so tried an order which seemed logical.  I find it best to not saw off your lines before you need them.  The first cut was the half way up line.  The ryoba cut through the oak very easily and pretty fast (mine is a Bakuma 250 from Dieter Schmidt’s Fine Tools).  Then I cut down the sides of the dovetail;



…here I’m not quite following the line, but at least I was cutting into the bit I didn’t want.  I read somewhere the suggestion that on the male pieces you want to cut down the outside of your marked line and on female pieces on the inside of the line.  This should leave you a lines-width bit of wood to play around with when it comes to fitting.  If I’ve got that wrong, then I’ve got a lines-width bit of air to play with.  Then I cross-cut the waste off to leave;



…some bits of wood of various shapes.  There are two square recesses at the bottom on each side, for these I cut diagonals across all the lines, corner to corner and had a bit of waste I could remove fully;



…which left a couple of triangles to get out with a chisel.  At this point I was worried as I hadn’t any broken whetstones left, so for the second time today I got ‘em off the top of the fridge-freezer and sharpened a medium chisel.  This I bashed into the corners, first one way;



…then t’other;



There may be an easier or better way of doing this and if anyone knows please tell me before tomorrow!  After a bit of bashing, paring and swearing I sort of nearly finished one side of the joint;



Then it started to look like it was going to get dark and it was getting a bit nippy so I bailed out for the day and came in, to see the beloved munching off with the last of the Hobnobs!  The BBC says there’s heavy rain forecast for tomorrow, so I’m getting my flip-flops and shorts out.  If they’re actually correct you may not hear from me for a day or two.

TTFN

awemawson:
This reminds me of my school carpentry lessons where all we did was joints. I'd swear the the workshop teacher would deliberately give us bits with nasty knots in 'exactly' where he wanted a dovetail. He was an evil little welshman with a chip on his shoulder bigger than a trunk of English Oak !

What he didn't know was we'd take his nasty bits of knotty wood into the metalwork shop and cut the dovetails on the band saw, then clean them up with a chisel so he couldn't tell  :ddb:

chipenter:
Bash the chisel vertically on the line then split the end grain the amount you have cut down with the chisel , and repeat the corner of the chisel works best start on the outside and work in about an eighth at a time , forget the Japanese joints hears some British ones http://www.greenoakcarpentry.co.uk/wp-content/uploads/greenoakcarpentry-joints-presentation-lowres-for-web.pdf .

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