Thread: King-size bed design question...

I've had a very crude bed in the past structurally similar to this. Kneeling or sitting on the edge of the bed will easily (e.g. sitting down without being careful) move the slats/mattress, although that bed was something strange (smaller than a double but larger than a king-size single). Size and weight of the king mattress will help this though. You'd need to screw each slat to each rail i think. The slats in mine weren't secured, just laid out across the stretcher rails (with heavy fabric stapled to each slat to space them when they are stretched from head to toe of the bed). Nor were the stretchers underneath fixed to each other (i.e., just the slats sitting across them).

It will work i reckon, but i'd be careful moving it and i would strongly lean towards keeping the stretchers underneath as wide as possible without losing look/style you are going for.

But that's all just my personal opinion, so take it all with a grain of salt.

RM

Would not put the that much over hang on the thing. Too much risk of instability.

I'm not sure, but a king size bed might need three stretchers, particularly if it is to carry extra weight.

I would also be worried by the bed head design. Looks like the pillows will slip through.

Looks like too much cantilever/overhang, from the drawing at least. Sitting on the edge may tip the bed?

I do a very simple 'futon style' double bed with two "feet" [almost full width] and two full length rails halved into them [so it's almost knockdown, ie no fixings] very stable, doesn't squeak! not too high off the floor and screw slats onto the rails. Slats are old rosewood T &V 19mm with the t & v machined off. Rail to outside edge of bed distance is about 10" but could be a little more if wanted. Up here in the sub-tropics I think the mattress should be allowed to breathe so I dont have the slats too close together, also the headboard should be placed so as NOT to lose pillows down the back. Usually a nice piece of bark-edge 6" x 11/4" works well there. With the bark long-gone of course. About 35mm is adequate for feet and rails. Sorry to mix dimensions but I grew up using both. So yes I'm old. But still dancin'.
For what it's worth.

cheers,

rich

The bed head isn't a 'design', it's just what I drew in Sketchup to illustrate which end is which.

It's the potential instability from some giant bugger (ie. me) sitting on the edge I was most interested in. I know I've seen someone post the calculations for overhang on a dining table before but the search function is thumbing its nose at me.

Artme - my gut feeling is that 2 vs 3 stretchers depends on where I can put the rails? On a KS bed with the feet on the corners you've got an unsupported ~2m span down the length of the bed, although obviously most (all?) KS beds seem to have extra legs.

My rough sketch above has a <1m span between the stretchers, and 400mm (oops, not 500 - KS is only 1.8 wide) overhang, so it's no more span than a single bed. I suppose the question is how much do I need to spread the stretchers apart to stop the thing from tipping...?

Yes I wasn't having a shot at your sketch, would never do that.

And it did show up the potential for tipping - maybe with not just you but a few kids as well sitting on the edge [which could happen].

But then a KS mattress IS a bloody big heavy chunk of material which may just counterbalance enough. Maybe make the centre [rail] spacing 1200?

cheers, rich

Rail spacing may well depend on a couple of factors:

*The strength of the rails ( stretchers ). This in turn is effected by the inherant strength of the timber used and its dimensions.

*The strength of the slats. Again effected by timber strength and size. This may be overcome to some extent by using bowed slats, as seen on some beds.

Our bed in Oz, which is queensize, had the slats screwed to each outside supporting rail. The supporting rail is anchored ( screwed and glued ) to the side of the bed.

As journeyman says, you will need to have a method to keep the whole thing square. Perhaps a couple of diagonal braces secured on the underside of the stetchers, as well as screwing each slat to each stretcher.

Stretchers - I've got a couple of pieces of 3200x370x55 jarrah which have been happily drying for 2 years, so ~150x50 stretchers are easily possible. My gut says I shouldn't need more than 120x50 though.

Slats - taken from my vast collection of recycled "tassie oak", mostly 1900x60x40 or bigger. Funnily enough recovered (by someone far more patient than I) from single bed frames.

Legs/headboard frame - made from 100x150 recycled jarrah fence posts.

Headboard - not sure...

I was thinking of recessing the stretchers & rails by ~10mm each where they cross, making a quasi-half-lap joint, and possibly pin them with a loose tenon. Should stop them from bouncing around and reduce the bed's ability to twist itself but means I can still break it down if necessary, because it ain't going to be light...

Plenty of size there - depth is what you need for the rails so 150mm is fine.
If it were me I'd lighten that up by going down to 35/38mm thickness I try to look at simple, light and strong with every article that has to bear loads. Somewhere, mate, sometime that bed will have to be broken down for transporting, maybe only to the next bedroom, but it's gonna happen. So bearing [sorry!] in mind that you're using that 'J' wood I admire so much, the lighter/finer the better, eh? And it looks better too, not so much like some landscape gardener sticking sleepers together with 12mm gal bolts!
'Tho I admit there's a place for that sort of thing [and as soon as you can pull it apart again it makes wonderful garden edging!!]
Use less timber and bring a little elegance into it. [check out someof Krenov's stuff, often used to be in FWW.]
And those nice deep [32mm/1,1/4"] tight halved joints keep it square naturally. AND knock down so easily.

So by now you're like me at the end of a Lindy lesson at 10 in the evening -- suffering from extreme brain overload! I'll try and get a pic or 3 up in the next few days so you can see what I'm on about.

Thats enough lecture & humbug from meself, take what you want/need from it. And Artme's talkin' good basics too.

Best regards,

richie

Originally Posted by Juffy

I was thinking of recessing the stretchers & rails by ~10mm each where they cross, making a quasi-half-lap joint, and possibly pin them with a loose tenon. Should stop them from bouncing around and reduce the bed's ability to twist itself but means I can still break it down if necessary, because it ain't going to be light...

Good idea.

As richie says it is the depth you want in the stretchers, not the width so fine them down a bit. 150 maybe overkill on the depth. How about setting up a stretcher and testing it. Sit in the middle and bounce around a little. If It's OK. take 10mm off until it breaks. Them go from there.

It appears to me that this design would be unstable due to the overhang. Some people sleep towards the edge of the bed too and not in the middle of their half so this might be a problem. I guess this is why beds are designed the way they are. Interesting that you want to deviate from the typical, traditional designs of beds though and this is just my thoughts on the matter and I have been wrong before. It may work with no problems whatsoever.

I've come around to thinking that 4-500mm overhang may well be too much. 300mm might be a better number, with a 1200 span in the middle...will have to draw up another sketch from everyone's input.

Originally Posted by munruben

It appears to me that this design would be unstable due to the overhang. Some people sleep towards the edge of the bed too and not in the middle of their half so this might be a problem.

Another thing that's just occurred to me is how to minimise bounce - if I wriggle around on the edge of the bed, on the outboard side of the stretcher, it would amplify that movement at the long end of the lever (stretchers) - ie. where SWMBO is trying to sleep. This would not promote nocturnal harmony...

I don't think tipping the bed itself should be a real issue, the bed as a whole will weigh more than even I do (120ish kg), but it'd be nice to run some calculations on that - I *know* someone's posted the calculations for tipping dining tables by leaning on the edge, but I just can't find the post. Might have to dig out my year 12 physics knowledge of levers...

Interesting that you want to deviate from the typical, traditional designs of beds though and this is just my thoughts on the matter and I have been wrong before.

Have you seen my table? I don't build things the normal way.

Thanks for the input so far, everyone - 'tis very much appreciated.

Go down to your local railway station, then lay on your back on one of the rails for a bit and I'm guessing you will get the idea, there was a princess as fables go that could feel a pea hidden under a pile of mattresses, my guess is your gunna feel like your laying on a railway line.
Nice graphics bad design! Sorry!

Originally Posted by Oddjob1

my guess is your gunna feel like your laying on a railway line.

I....don't follow you. Are you suggesting the slats will bend enough that the occupants would feel the stretcher as a ridge through the mattress?

Your back is very sensitive, if you place an inflexible rail directly beneath it, even under cross beams, your back will tell you it's there.
Best build it and give it a try, or more quickly, place a slat of hardwood under your mattress where your design indicates, by morning or sooner you will know what I mean. Go on, do it now and sleep on it, if you can!