19
Oct 20

TortoiseShack

So there’s a podcast I listen to here in Ireland called TortoiseShack (I guess they’re more a channel than a single podcast these days, they’ve spun up dedicated special-interest podcasts), which has a lot of voices we don’t get to hear on RTE much. Longer chats with data protection experts like Simon McGarr (which is how I got interested in them), talks on green politics with people who know why you can’t have a forest of walnut trees, discussions on the homeless crisis with Peter McVerry, that sort of thing.

I’ve been throwing the price of a cup of coffee at them for a while now on patreon, but I was reading how one of the two guys who does the podcast is running 2,020 miles this year for charity (he finishes next week) and I had the idea to make them a desk ornament because if you look at their logo, it’s almost like it was designed to be made as small bits on the lathe and joined together:

I figured, the head is just an egg, the legs and neck are just slightly curved cylinders, the tail is just a cone, and the top and bottom shells are just unhollowed bowls. Sure, there are tenons and mortices and the neck hole of the top shell might need a holesaw but I have those, and maybe that angle at the front would be a cut on the bandsaw with the table at an angle, but all that’s doable. So over the last week I did it.

First five minutes went well, I missed a flaw in a bowl blank because it was painted over (what idiot thought that was a good idea?) and it bounced off my faceplate (remember, Norm was right). But the rest of the turning was easy enough, and I put a small tenon on the back of the bowl where the woodscrew was holding it (and a little undercut) for reasons that show up later.

Nice grain pattern really. Wish I had brown stain to match the logo better but oh well. You can see the lower shell on the lathe there in the top left as well, the yellow stain isn’t very evident there though. I think I’d have needed to go full-on Furini with an airbrush to get colours that matched the logo though, so I’m settling for just evoking it rather than replicating it 😀 I’m also skipping the plates for the same reason – I could dremel them out but the design on the 2D logo doesn’t actually translate to 3D well when you try to figure out what the shell would look like from the top, so I’ll leave that bit out so long as it’s still recognisable at the end.

There’s a tenon on each piece here which is why the gap between shells is so large. Next up, the head, neck, legs and tail…

The green stain looks a lot nicer here, but it doesn’t stay that pronounced through sanding alas – here I’d stopped sanding at 120 hoping to get deep penetration of the stain, leave it overnight then hit it with sanding sealer when the stain was fully dry and sand to 320. This didn’t work – the sanding acted like the stain was still fresh and a lot of it came off. But that aside, this part went quickly – I did the head and legs over one lunch hour and the tail and neck in an hour that evening (the legs all came from one blank I’d made to make a toolhandle from but I wasn’t using it, so they were very fast to get to this stage).

Yes, I know. Go on, laugh away, get it out of your system…

That’s everything drying at the end of the first day. Everything from here is just fiddling and fettling really.

Right so we need tenons and mortices. The legs, neck and tail have tenons already, and to drill the mortices I have this new famag 1″ forstner bit and a drill 😀

The neck and head were easy enough, and the mortices for the legs go in the underneath of the shell. At which point I discovered one of the tenons was not like the others…

Whoops. Much smaller, way too loose. No way glue’s going to cover over that much of a gap, there’s a good 1-2mm on either side between tenon and mortice. So…. grab one of the other bits of spindle blank I’d made up and the #04…

Make a few shavings, moderately thick…

…wrap the tenon and glue the shaving in place…

Not perfect, and if I was less lazy I’d remake the part, but it’ll fit and hold now.

There was also a lot of fiddling with scribing the shoulders of the tenon to the surface of the shell, which was curved and of course the mortices are angled as well so that was fun. Hold a pencil flat on the surface, scribe against the leg, trim to that line with a chisel and undercut as well, then check the fit and fettle as needed. Fiddly, but not complicated.

And with that done, it was time to cut the neck hole in the top shell. Pillar drill, hole saw from lidl, janky-as-anything workholding setup with the shell propped up on a block at an angle and away I went, expecting it to all go horribly wrong at any moment. And it kinda did, I had to stop half-way through and use a chisel to knock off some waste because the saw was bottoming out on the top of the shell. And the second time I just took it out of the pillar drill and tried to finish the cut with the fretsaw by hand but couldn’t, so I put the holesaw in the handdrill and used the kerf of the cut so far to guide the last inch of the cut, knocking out more waste with a chisel as I went. Messy and janky and there’s about six better ways to do it that I don’t know of, but it worked and a quick cut on the bandsaw with a tilted table later and the top shell was done.

The mortice for the tail was cut by hand with a smaller holesaw (as the tail’s tenon was also too small and I figured I’d save myself another shaving trick).

Right, now I just need to turn that tenon off and make it a shallow mortice to match the lower shell’s tenon and….

oh. Shite. What do I hold the sodding thing by? There’s no tenon on the back. Well. Feck. Off I ran to youtube looking for a thing I’d seen last month that I thought couldn’t possibly work, and figured I’d take a chance.

Took a small scrap block, pinned it up against the closed chuck with the tailstock, turned it roundish, put a tenon on it, reversed it and grabbed the tenon in the chuck, faced it off, made the face concave and chamfered the face’s edge, and viola:

Glue block. You think you’re nervous now, just you wait. Put the shell into the concavity, and line it up by eye and pin it with the tailstock…

That looks very janky, how are we gluing that asymmetric unbalanced load… why are you reaching for the hot-melt glue gun?

You’re shitting me.

Oh, seriously, there is no way this works. I’m going to lose teeth doing this.

gonnadiegonnadiegonnahaveastupidcoronersreportgonnadiegonnadie…

Wtf? It worked? I lived? A thing on youtube worked? What the hell…

And painting the glue line with isopropanol (or meths if you have none) gets the glue to let go a minute or three later with no surface damage. This is witchcraft.

But now I can glue up, and here you see why the wormscrews were good – the hole left behind fits a small dowel for alignment. Had to trim the tail to get a good fit but…

And now we let the glue dry. Shims are in place to keep the gap on the shell even, and the shim under the leg is because one of the legs in the logo is in the air as the tortoise is trotting. Yes, it’s a back leg in the logo. Glue-ups are hectic, okay, mixing up front and back is just a thing that can happen…

And there we go. I’ve done some pre-finishing here. The various parts have all been sanded to 320 by this point, and treated with yorkshire grit, yorkshire grit microfine and a bit of hampshire sheen, but I then put the buffing wheels on the lathe and ran up through the wheels with them to get to this level. I branded my mark into the bottom shell and sprayed with melamine lacquer and gave that overnight to cure, then cut back with 0000 steel wool the next lunchtime. For eyes, I took some googley eyes from the case of them I have here (what? don’t you have a box of googley eyes? why on earth not?) and just used the pupils. Attached with superglue, then point the heatgun at them for a minute until they soften and then mould them to the curved surface of the face. Let it all cool, give it another coat of melamine, let that cure off and then give the shell a final coat of microcrystalline wax and hand buff to a shine.

It’s not too bad I think.

I can even see it helping out with fundraising for the podcast…

“The tortoiseshack lays on its back, its belly baking in the hot sun, beating its legs trying to turn itself over but it can’t. Not without your help. But you’re not subscribing on patreon. Why is that Leon?”

‘course, now I have to make a second one for Calum. At least now I know one or two things to not do for the next one…


19
Oct 20

New tools

You know how aliexpress isn’t so much shopping as it is buying surprise presents for your future self?
Well, a while back I saw this neat tool being used for layout in a Korean woodworking video:

It was basically a cross between a marking gauge and a vernier calipers and I thought “wow” and looked for one and found it was over a hundred quid and thought “nope”. But aliexpress did knockoff aluminium ones for about twenty quid and I figured why not, so I ordered one.

In January. I mean, covid was in the promed email lists by then but it wasn’t on the radar over here very much and we thought it’d be a bit less of a thing than it became. But anyway, point is, I forgot about it completely and then the other day it turned up out of the blue:

It is very nifty 😀 Looking forward to giving it a workout.

And in one of those synchronicity things, on the same day a new order arrived from Dictum:

I swear, the nicest things come in boxes like this 😀

And I can hollow! It’s the mini version of the crown revolution hollowing tool. I did try undercutting with the tools I have but… well, it’s a bit of a mess. You really do need to be able to bend and heat-treat metal to make a hollower and I don’t have the kit here for that (one day…). So this one is ring tool which is a new one on me, but it has a chipbreaker so it’s kindof a beginner’s ring tool and it’s actually really easy to use:

Negative rake angle (meaning hold up the tool a bit so it’s angled downwards when it meets the wood) and rotate counterclockwise by about 45 degrees according to the youtube instruction videos and away you go. It also comes with another tip (and there are a few more you can buy) which works well for scraping – and you can get right up to under the rim of a bowl with this which I’ve been wanting to do for a while ‘cos it just looks nicer. I had a play with it and it turned out really nice:

The blank is cherry, but with a lovely huge knot in one side which is why it has that lovely pattern in it. It’s on a worm screw there, I reveresed it for hollowing and it came out nicely:

It’s not very big or very thin-walled, I was just playing, but I’m looking forward to doing more of this.

The other book in that order was Campaign Furniture from Lost Art Press – there’s a piece I want to build in that style soon and that’s the best reference I’ve found so far. It’s an interesting style – not as elegant as Shaker, but wonderfully functional and minimalist. That should be a fun build.

And then the next day, a rutlands order landed – they had the same chuck I have now, but with a slightly different name (they called mine the 3″ Xact and the new name is the Precision 75 but they’re the same chuck as far as I can see and the jaws are compatible) as ex-demo stock so it was going for a lot less than half price and I grabbed one – now my cole jaws are on a dedicated chuck which saves time. I must keep an eye out for those if they come up that cheap again, it’s a nice luxury. 75mm/3″ chucks are pretty cheap compared to even 4″ chucks though – I see these youtubers like Stuart Furini open a drawer and casually reach in and pull out a chuck from five or six other six-inch chucks and I wince at the pricetags 😀

I did also get a new forstner bit on clearance from rutlands – the ones I had were from lidl and, well, charitably, lidl’s forstner bits aren’t up to the standard of lidl’s chisels (which btw, are bloody excellent – they’re as good as the aldi chisels and stop laughing because if they’re good enough for Paul Sellers, they’re better than what you or I need….). But forstner bits are a bit more demanding than chisels, and good ones are spectacularly pricey. The ones I had seen recommended as good are by Famag in Germany and sets of those get up to nearly three hundred quid. But here was rutlands selling them by the individual bit for just over twenty quid and for hollowing, I just wanted the one so I got a one-inch one…

…and it’s like night and day. My lidl ones started smoking and burning the wood on their first cut even though I’d taken the diamond paddles to them to hone the edges first, and they were more scraping out wood than anything else. The Famag cut the wood like it was cheddar cheese. It’s seriously impressive the difference between them. You really do get your money’s worth. I used this one to make that little bowl above and it’s also small enough that you can use it for making mortices for small tenons if you’re assembling pieces. Another one I need to keep an eye out for if they come up cheap.

I was hoping to end this one with a new tool I’d made myself but… well, I cut the steel and went to drill and tap the hole for the screw to hold in the carbide tip and the drill bit wouldn’t cut and then shattered and flew everywhere.

Barely even dented it. So two lessons there – firstly, safety glasses (yes, I was wearing mine). Norm was right. And secondly, look closely at the piece of steel you pick up.

I know it’s faint, but that reads HSS not Mild Steel…

Oh well. I’ll grind it into a bedan or something…