29
Jun 18

Sunbathing poplar

So asking on UKworkshop about that clamping problem I was thinking about with the shelf/desk project led to the conclusion that housing joints won’t work and tapered sliding dovetail joints are the better choice. That will probably mean some router work because of the precision needed – I could probably make a tapered dovetail joint that wouldn’t pull out, but one that would be precise enough to maintain the shelves against racking would be beyond me. So a new router bit, get that router table out of storage and actually assemble it (I basically picked it up in Lidl intending to use parts of it in a proper router table at some point and then just developed a dislike for routers in general 😀 ), and that sorts two of the shelves out; the third gets dovetailed into the top shelf which will also help with racking.

And I keep sketching the idea in my head to try to nail down the bits of it.

It does feel like I’m trying to squeeze the shape I want out of almost not enough wood; the 8″ wide poplar planks I have might not be wide enough and I might need to do a run to the timber yard for some 12″ wide boards. Which would mean a half-day off work and I’d wind up buying a lot more than one board because if you’re giving up vacation time, you buy in batches. So I’d rather get the pieces out of what I have, but if I can’t, there will be more walnut and poplar and maybe some utile to see what that’s like to work with… see, this is the problem with going to the timber yard 😀

Meanwhile, we’re in a heat wave here and the poplar I have has these green streaks, so I figure I’d let it sunbathe for a few days to get rid of them and get that lovely honey colour poplar gets…

Better than a shop dog 😀

The colour of the wood is easing but it’s not a one-day thing…

Before on the left, after on the right in both cases there (the badge is to get a white balance reference but even that didn’t help much, the direct sunlight just blows the camera away).

I’ll keep doing that for a few days, see if it helps.

I also took the opportunity to see what the side would look like with a 1:1 sketch.

(Yes, we’re reseeding that bit of the lawn, we’re just waiting for the weather to break next week or the seeds wouldn’t have a chance).

That bottom desk shelf really looks too low, I know, but I measured Junior’s knees when he was sitting down and nope, that’s the right height. Kids are just small and the scale looks all wrong 😀

And today, since it was the middle of a heatwave, I had some hardware, tools and a chunk of a tree shipped to the office so I could carry them home…

These quadrant hinges are very definitely *not* brusso hinges 😀 But they will suffice to learn and experiment with. Plus, no damned nails, so hopefully less fiddly.

Nobody in the office could identify this 😀
It’s an electric heated bending iron, normally used for making violins. This one’s not temperature controlled, it’s just a PTC resistor in a metal housing that you plug into the mains. The fin bit heats up and then I can use that to bend stringing around sharper corners. Yeah, I could have used a hot air gun, but here’s the thing – in an 8×6 shed, any hot air (at 100C or so) that leaves the gun tends to hit something while still hot enough to damage stuff, especially with foam on the roof for soundproofing, so I decided to go buy this thing (hey, it cost a total of €37 delivered from China via the customs department) instead.

But.

There’s a rule I have for electric stuff you buy off aliexpress (or ebay). If it’s on batteries, it’s probably okay. But if it plugs into the mains, you take the thing apart and check it before it ever goes into a socket, so this got disassembled in the electronics lab and tested for shorts, for the case being connected to the live wire, all that sort of stuff. But no, it seems grand, so out to the shed…

I said it looked grand, not that I trusted it yet 😀 More testing for voltages, waiting to see if the temperature stabilised properly and so forth (that bit of sapele there is to become the base it gets fastened to so I can holdfast it to the bench). All the electrical tests seem okay so far…

The temperature seems a little high mind you, but I think it was made for 110V rather than our 240V. More monitoring needed really and I might want to put some handles on that bit of wood because the fin is not very well isolated thermally from the base…

I worry about the temperature running away too far – if it melted insulation then the case might wind up live and that could be fun. I mean, there’s no ground in the shed really, it’s a wooden floor, but still. Not exactly ideal. Hence, add some handles to the base to pick the thing up and move it about. And maybe some wooden rails along side it to act as hand rests for when I need to steady my hands for particularly delicate bending work.

And what will it be bending? Well, I finally found a commercial source for thick veneers (in this case, 1.4mm thick which is perfect for what I want it for – it’ll get a bit of handplane work to trim it to the thickness of the groove, but with one side of the strip being thinner so it wedges in there).

Some sycamore…

and to compare it against, some maple…

and just for fun, some cedar of lebanon…

That last one is seriously aromatic. I have got to find a source for actual boards of this to use as drawer bottoms, I now know exactly why they used to use this for that purpose. It’s a nice smell, but you know you’re not getting mothholes in your shirts if the drawer is made of this stuff.

Even the bit of hardboard they used to ship this stuff will be of use, if only for drawer bottom material and the like. Happy with that find, now I just have to wait for brexit to screw up the trade rules between here and the UK and for all this wood to become unavailable again. Hell, it might be an idea to stockpile, the way things look to be going…

(You laugh, but you know how house prices in Ireland are rising faster than a SpaceX launch? And you know how we use timber for building houses in everything from making doors and stairs to roof eaves, scaffolding and so on? That timber all comes from the UK because Irish timber yards are too small to buy on the continent because we’re just not that big a country – we have 4 million people, they have 50, and they build more so they buy wood by the hundreds of tons and we buy off their yards and ship it to here. Brexit is going to throw a huge spanner in that, stuff will either have to come from the continent meaning higher purchase prices, higher logistics cost and so on; or yards here will have to buy stuff from UK yards at enormously higher prices. And all that gets passed on to the final house price here. Stockpiling doesn’t seem so ridiculous now, does it, eh?)

 


27
Jun 18

Can you tell what it is yet?

Well, that empty In Progress… list lasted a while, didn’t it?
Though I actually went back through my notebook…

Five euro or so in TK Maxx, the very height of bohemian luxury

Five euro or so in TK Maxx, the very height of bohemian luxury

…and every project in there bar this one is marked as Done or (in one or two cases) marked as Won’t Do, What Was I Thinking. This one will be a small bookshelf for Calum. Well, small to you and me, but not to him. The idea is this will have his books and toys and assorted child-related detritus now (he’s six and between kindergarten and vorschule so just learning to read and write at the moment) and we figure he really won’t have “homework” in the traditional I-need-a-proper-desk-and-I-still-don’t-want-to-do-it sense until he’s nine or ten, so off to the internet I go and I grab the UK90 based growth rate charts for boys aged 2 to 18, and find Calum’s centrile, so now I have his current height and his predicted height until he’s nine (it’s not that accurate, they change centriles faster than they change their socks if you don’t tell them to, but it’s better than pulling a number completely out of thin air.

Then I grab my copy of The Woodworker’s Guide to Furniture Design (thanks to a Richard Maguire recommendation and so far well worth buying) and dig out the bits on figuring out things like how high the underside of a table has to be from someone’s height and how high someone can reach given their height and so on and I spend a few minutes sketching stick figures and working out the height of the top of the very top shelf (which is to be the highest part of the build) and come up with 48″.

Then I dig out my copy of the bible…

And grab the tangential and radial expansion rates for poplar over the 30% relative humidity span you see in an Irish home in the average year (3.2% and 1.2% respectively), discover that my copy of the bibles is too old to have that data for american black walnut (7.8% and 5.5% respectively according to the woodbin’s online calculator but it lists 8.2% and 4.6% shrinkage rates for poplar respectively so I’m now doubting the bible, again).
Then to the sagulator to quickly see if the shelves would snap if Calum stood in the middle of them when he’s nine and no, should be fine – 0.05in deflection so that’s grand.

For the general design, I don’t yet have it nailed down. I’ve been looking carefully at Paul Seller’s leaning wallshelves because they have a lot of elements I want to steal:

But I don’t want the half-lap joints he uses because this is going to be abused by a six-year-old boy who likes hammers and those joints seemed to be giving up a lot of the strength of the boards. Plus I hate the little end bits off the sides of the bookshelf because anything you put there is just going to wind up on the floor. And I want the bottom shelf to come forward from the sides by a fair few inches and to have a curve across the front that’s echoed in the upper shelves; and I might want to put a cantilevered support element or two under the desk as well to add strength once the shelf is forward of the sides, but we’ll see – the sagulator is saying I don’t need it, but it might look better for it.

That gives me :

  • Top shelf at 48″
  • Bottom shelf at 17″ (it’ll double as a play surface/desk)
  • One intermediate shelf about 18″ above the bottom shelf
  • Poplar for everything bar the bottom shelf
  • Stringing on the bottom shelf to inlay things like a racing track for toy cars into the surface as well as things like letters and the like in various places
  • Curves everywhere instead of sharp edges and corners for little eyeballs
  • A serious set of problems with clamping curved bits into housing joints during construction.

So, time to think it over for a few days, do some sketches on paper, maybe a few SketchUp cad sketches, get a sense for it in my head, and ask a few construction-related question on the woodworking forums to see if I can steal more good ideas.

Until then though, the stock of poplar that I have needs to be dug out and looked at for stocktaking, and the stock of walnut…

It’s a mess back there and that’s after I extracted the boards and tidied it back up. Now, let’s see….

Right. We’re shy on wide long boards of poplar, but we have some just-about-9″ wide ones that would do for sides, a few 12″ wide boards that could be picked from for the intermediate shelf, and some choices for the top shelf as well, even if we didn’t get that from an offcut. I’ll have to leave them out in the sun for a day or so though, that green staining on the boards will dissipate into that yellow honey colour of the wider boards there in a few days with the 30C weather we’re getting at the moment here.

The bottom shelf though – if I want it to be 36″ wide, I pretty much have to cut into both my remaining walnut boards to make up the panel. Or I could settle for 30″ and hack one board in half and edge joint it to itself. Or if the sides splayed out from ~30″ at the back to ~36″ at the front of the shelf, I could probably get that from one board as well.

Decisions, decisions…