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Dazza33
4th Jan 2019, 08:04 AM
Hi
Recently saw a new wood project. Its a chair that folds to a daybed. The cut list has 2 inch x 8inch timber 30inch long. Many others similar. Went to Bunnings but couldn't locate 2inch thick. Before I embarrass myself at a timber yard just want to know is it possible to get such thicknesses. It seems a lot. The chair is for my man cave so a hardwood might be to heavy. I can post a link to the chair if allowed to give a better idea.
Thanks for any help.

poundy
4th Jan 2019, 08:42 AM
45mm is near enough? That's what I'd do - 90x45 instead and build up 2x wide to get the nominal 8" wide. Posting the link to the design is fine as long as it's a freely available one.

Dazza33
4th Jan 2019, 08:56 AM
Ana White | Twin Sleeper Chair - DIY Projects (http://www.ana-white.com/2018/10/free_plans/twin-sleeper-chair)

Yes free plans. About half way down the page is cut list.
If i just dowel 2 90mm together to get approx 8 inch (200mm). That does sound a bit easier.



45mm is near enough? That's what I'd do - 90x45 instead and build up 2x wide to get the nominal 8" wide. Posting the link to the design is fine as long as it's a freely available one.

elanjacobs
4th Jan 2019, 10:03 AM
You can get 2" no problem, but it will be rough sawn so you'll be down to 45ish by the time it's dressed. 2x8" seems like overkill though, where I used to work we made sofa frames from 32x145mm hardwood and that was easily strong enough.

Midnight Man
4th Jan 2019, 10:52 AM
If the plans are US based (and it sounds like they are given imperial measurements), bear in mind what the Americans call 1x2 or 2x4 (inches) isn't actually that measurement.

See here: Lumber Dimensions (http://mistupid.com/homeimpr/lumber.htm)

I have a sawhorse project that asks for 2x4, and when checking, I found 90x45 (mm) untreated pine would work just fine (I would mill down the 45mm to 38mm and the same for the 90mm to 89mm (if needed) as per the linked chart). I needed to make sure I was using the exact size lumber on this because of multiple angles that would be thrown out by using different size timber, so I went hunting :)

Your 2x8 material might actually be 38mm x 184mm - you'll need to check your plans fairly carefully to see if this is the case.

Good idea to go to a timber yard, better material than Bunnings and likely cheaper. There are a heap of places in Sydney that do furniture grade pine - one that I know of but haven't dealt with yet is Barrenjoey Timber, from memory in Mona Vale. They have stuff over the size you need, obviously they don't have the exact size you want, so it'll need to be milled down. If you have your own thicknesser and table saw/band saw, you could handle this yourself. If not, the timber yard may be able to help, or perhaps your local Mens Shed will have the machines needed.

ian
5th Jan 2019, 04:33 AM
Ana White | Twin Sleeper Chair - DIY Projects (http://www.ana-white.com/2018/10/free_plans/twin-sleeper-chair)

Yes free plans. About half way down the page is cut list.
If i just dowel 2 90mm together to get approx 8 inch (200mm). That does sound a bit easier.just some background

2 x 8 (and 2 x 10 and 2 x 12) are standard size framing timbers in the US and Canada. Every Bunnings equivalent carries them and most will cut down the standard 8, 10, 12 or 16 foot sticks to the lengths you require. Locally (Alberta, CAN) it's sold as SPF -- for Spruce, Pine or Fir -- or what ever they were cutting three weeks ago. So for a US "Home and Gardens" reader the sizes suggested are pretty much bog standard, get anywhere, softwood dimensions. To make you cry, a 5m long stick of 2 x 8 will set you back less than $25 AUD, i.e. it costs less than $5 / m meaning that milling it to smaller dimensions is not cost effective. If you pick over the piles there is some very nice stuff bundled as house framing timber.
Material less than 2" nominal is, in my experience, generally only available as treated decking or rough sawn fence panels.

If I were contemplating a similar chair using what is readily available in Australia, I doubt that I'd go much thicker than about 25 mm nominal. And I would seriously look at cutting up one or two of Bunnings 19 mm pre-sanded pine panels to get the widths required.
That chair is built with 2" framing timber because it's the cheapest stuff available in the US, it doesn't need 2" material for strength.

Fuzzie
5th Jan 2019, 09:08 AM
That project looks like something you might make out of sleepers from the garden section. 200x50 treated pine runs at about $8/m at the green shed.

poundy
5th Jan 2019, 09:32 AM
I agree with Ian, I'd use finished pine in 19mm or if you wanted something more "bulky" looking, 35mm. eg https://www.bunnings.com.au/184-x-19mm-x-2-4m-premium-grade-dressed-pine_p8401471

GraemeCook
6th Jan 2019, 02:36 PM
You can get 2" no problem, but it will be rough sawn so you'll be down to 45ish by the time it's dressed. 2x8" seems like overkill though, where I used to work we made sofa frames from 32x145mm hardwood and that was easily strong enough.

Hi Elan

I thought that the thickness of the wood was an essential part of the aesthetic of this design. Thin the timber, and its visual appeal changes.

When I lived in Boston the most popular timbers (read cheapest) were Eastern White Pine (Pinus strobus - density = 0.400 and Western White Pine (Pinus monticola - density = 0.43) and I presume that these are the intended species for the chair/bed. Both of these are considerably lighter than radiata pine (Pinus radiata - density = 0.51). Changing the wood from EWP to radiata, leaving all dimensions unchanged, would increase the weight by 27.5%; changing to an Oz hard wood could double the weight.

As one would almost certainly have to move the chair when converting it from chair to bed this increased weight would be undesirable; it would make it harder to do, key impact on the chair/bed's functionality.

Thus I would suggest that it is very important to this design to use very light weight timbers. The only one's that I can think of that are reasonably available and affordable are:

western red cedar - Thuja plicata - density = 0.37
paulonia - Paulownia tomentosa - density = 0.28


I saw WRC at a local suppliers last week in sizes up to 200 x 45 mm.



Cheers

Graeme

ian
6th Jan 2019, 04:18 PM
I thought that the thickness of the wood was an essential part of the aesthetic of this design. Thin the timber, and its visual appeal changes.

When I lived in Boston the most popular timbers (read cheapest) were Eastern White Pine (Pinus strobus - density = 0.400 and Western White Pine (Pinus monticola - density = 0.43) and I presume that these are the intended species for the chair/bed. Both of these are considerably lighter than radiata pine (Pinus radiata - density = 0.51). Changing the wood from EWP to radiata, leaving all dimensions unchanged, would increase the weight by 27.5%; changing to an Oz hard wood could double the weight.

Thus I would suggest that it is very important to this design to use very light weight timbers. The only one's that I can think of that are reasonably available and affordable are:

western red cedar - Thuja plicata - density = 0.37
paulonia - Paulownia tomentosa - density = 0.28


I saw WRC at a local suppliers last week in sizes up to 200 x 45 mm.
I don't think so.
According to "Anna" "We spent about $100 [USD] on this chair"

The only way that statement is even remotely true, even if you allow an additional 50% for "optimism bias", is if the chair is built from bog standard 2 x 8 construction softwood lumber (which is 38 x 184 mm in real measures).
In Oz, that means Pinus Radiata

GraemeCook
6th Jan 2019, 09:49 PM
I don't think so.
According to "Anna" "We spent about $100 [USD] on this chair"

The only way that statement is even remotely true, even if you allow an additional 50% for "optimism bias", is if the chair is built from bog standard 2 x 8 construction softwood lumber (which is 38 x 184 mm in real measures).
In Oz, that means Pinus Radiata

Hi Ian

The Point is that radiata is significantly denser than the American equivalents.


Cheers

Graeme

Midnight Man
6th Jan 2019, 10:45 PM
Back-of-napkin mathematics, based on stated (as opposed to actual) lumber dimensions from the cut list *without* the plywood places the material in the region of 18.6% of a cube.

Using Radiata Pine (around 590Kg/cube) would be 109.7Kg timber
Using Western Red Cedar (around 350Kg/cube) would be 65.1Kg

Just IMHO, a 110Kg piece of furniture wouldn't be trivial to move around a room.

GraemeCook
7th Jan 2019, 09:22 AM
Back-of-napkin mathematics, based on stated (as opposed to actual) lumber dimensions from the cut list *without* the plywood places the material in the region of 18.6% of a cube.................


Thanks Midnight

And if he built it strong and used ironbark then it would weigh 205.7 kgs !
https://www.woodsolutions.com.au/wood-species/ironbark-grey


Cheers

Graeme

Bushmiller
7th Jan 2019, 10:03 AM
Dazza

I think Radiata Pine will be your only economical option. Radiata varies quite a bit in it's density according to tree maturity. Bootle's "Wood in Australia" gives a range from 450Kg/m3 to 580Kg/m3. WRC would be wondeful at 350Kg/m3 but very expensive I think although it will have the added benefit of no insects wanting to eat it. WRC is extremely soft and damages easily just from casual knocks. Much will depend on your budget.

Regards
Paul

Midnight Man
7th Jan 2019, 07:19 PM
Thanks Midnight

And if he built it strong and used ironbark then it would weigh 205.7 kgs !
https://www.woodsolutions.com.au/wood-species/ironbark-grey


Cheers

Graeme

I seem to remember a guy wanting to do just that with a similar design to this, but for an outdoor couch.

Whether he was going to use Ironbark, or just "hardwood" escapes me now, but I do remember a number of people cautioning him on the weight aspect.

elanjacobs
7th Jan 2019, 07:24 PM
What if you were to put some spring loaded castors under it? Enough spring to hold the chair up but not the added weight of a person

Midnight Man
7th Jan 2019, 10:44 PM
Interesting idea, Elan. I would suspect the challenge would be in finding the right castor? I don't know of this sort of device (though I can imagine it from the description), and thus I don't know how exacting they might be with regard to their carrying weight range... there is a storage bin inside the unit, and it's now going to come down to what may or may not be put in there over time?