# Adjustable shelves



## n0legs (16 Oct 2013)

:!:


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## AndyT (16 Oct 2013)

Here's one I prepared earlier! (about fifteen years ago, at a guess).






The technique is standard - I read about it one of Paul Hasluck's books.

At each corner, hidden behind a faceframe, is a vertical strip with sawtooth-like notches cut in it:






Shelves are held on battens with ends cut to fit in the notches, and have their corners cut off to give clearance:


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## mseries (16 Oct 2013)

You've got my 'Code Book' too. I have mislaid my copy and I saw it on Emmerdale, now it's on your shelf. Nice tip about the shelf system.


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## n0legs (16 Oct 2013)

:idea:


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## AndyT (16 Oct 2013)

n0legs":39z046ff said:


> Andy, that is brilliant !!
> Did you cut "saw tooth" strips as one, like in a stack, or individually ?
> Very nice work my friend.



I'm glad you like it. The chair conceals the slight sag on some of the more heavily laden shelves, which are 3/4" oak veneered blockboard edged with solid oak, with a scratchstock-made moulding. The inspiration for making it came when I spotted a carfull of oak skirting boards being skipped at an office re-fit. I bought a sheet of oak faced blockboard and some softwood T&G for the back, but all the rest was salvaged wood.

For cutting the notched strips I stacked them together so that any unevenness would be the same on all four. Most of the work was done on my trusty old Burgess three wheel bandsaw, with handwork when there was no room to swing the 6' lengths around.


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## AES (16 Oct 2013)

@n0legs:

I don't know anything at all about proper woodworking/cabinet making, etc, but you may care to know that when we moved into our present house here in Switzerland we "inherited" a large cupboard/bookshelf with glass doors from the previous owners. The shelves are adjustable and the "mechanism" looks exactly the same as Andy T has posted - even the proportions are very similar looking.

As a matter of interest we bought this house in 1993 and the previous owners built the house in the late 1960's. But from the look of the cupboard (style, very dark wood, complex mouldings, and what looks like hide glue holding the mouldings and some internal blocks in place) I'd guess the cupboard is much older than the house.

HTH
Krgds
AES


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## marcus (16 Oct 2013)

I love those saw tooth ones, though I've never done them myself. I tend to do wooden pins, which are also traditional — at least I've seen them on pieces well over a hundred years old.

Here's one I did earlier:






on this bookcase






They have to be made quite fat — at least 1/2" — or they tend to break when you pull them out. With a couple of simple jigs you can turn them out really quickly by hand once you have made the dowel.






You can also make them square like this which is a nice way. I think there are instructions in one of Krenov's books — you use a plug cutter in the drill press to make the round sockets for the holes.


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## AndyT (16 Oct 2013)

Marcus, I do like the look of that. 

Are your shelves strips of veneered board with solid wood for the moulded front edge?

And what did you do for spacing the holes? I think I would just walk some dividers along a line, but I've seen ideas for jigs and the simple idea of using a strip of pegboard as a guide.


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## marcus (16 Oct 2013)

Thanks Andy, yes I think the shelves were veneered birch ply with solid mouldings front and back, tongue and grooved into the ply. I marked the holes out by hand with a divider and square, it would be good to have a jig for that, as it is quite time awkward and time consuming drilling so many holes accurately on the drill press on long shelf sides, but I don't do it often enough to be worth making one.....


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## dickm (16 Oct 2013)

FWIW, two bits of our furniture use the "sawtooth" system and one of them is at least 120 years old. The maker's son was a very old man when I knew him in the 1940s.


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## n0legs (16 Oct 2013)

:!:


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## Togalosh (16 Oct 2013)

I have a Dutch Dresser (like a Welsh Dresser but with glazed doors instead of open shelves on the top section) & in the top section is the saw toothed design..I took the idea of it & did this instead as I wanted thin sides & had no bandsaw at the time.






This was only my second piece of furniture so the fit/workmanship wasn't great but it works well enough.


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## Shrubby (16 Oct 2013)

The sawtooth stuff was still for sale last time I was in France. The modern system with 5mm holes at 32mm spacing is called system32 - ubiquitous in modern knockdown furniture
I prefer library strip (tonk strip) it's more adjustable than 32mm and quick to use. Peter has used it in his fun with MDF thread
Matt


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## AndyT (19 Oct 2013)

Another method is to cut lots of horizontal housings for the shelves to slide into. This C17th bookcase in the V&A is an example:











Sorry the photos aren't brilliant but you should be able to see the stripy effect of all those housings a couple of inches apart. A dado plane would most likely have been used to cut them quickly and efficiently. 

According to Whelan's book on the wooden plane, there was even a special plane for making the sawtooth strips discussed earlier, but I don't think they are very common!


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## Jacob (19 Oct 2013)

Sawtooth or wooden pegs both excellent. I've got them both on some very old bits of furniture. 
My pegs are just 1/2" softwood dowels which have been working perfectly well for 100 years or so. They slightly indent the underside of the redwood shelves and self locate.
The sawtooth horizontal slat can be fixed in place by having a little rebate in the end of the shelf but it's not essential.
There are other patterns - I have one with semicircular cut outs. I think it was made in a batch by drilling a series of holes in a thick piece, slicing through and then splitting each one to make a pair. Come to think you could make a batch of sawtooth pattern the same way.


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## Teejay (6 Apr 2019)

AndyT":2ind8nyh said:


> Here's one I prepared earlier! (about fifteen years ago, at a guess).
> 
> 
> 
> ...



I have been searching for the best way to have adjustable shelves in an alcove build that is discreet and this might just be it.

I don't suppose you could take the books off one of the shelves and take more photos so I can get a better idea of the construction visually? Those are long shelves without sagging so I am interested also in seeing their construction.

Thanks.


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## Deadeye (6 Apr 2019)

Is anyone else secretly looking st what books are on the shelves as much as at the shelves themselves..?


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## woodbloke66 (6 Apr 2019)

I've also got a bookcase/shelving unit to do and was looking at the 'Sagulator' last night to try and work out the sag in a heavily laden bookshelf. I reckon blockboard (lipped and veneered) might offer a good solution but I haven't seen any around for years? - Rob


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## AndyT (6 Apr 2019)

Ok, for TJ and anyone else building something similar, here are some more photos and notes. 
The shelves are indeed 18mm oak faced blockboard. This has an inner core of strips of softwood, running along its length, with two layers of veneer (one cross-grain, one long grain) on each outer surface. It used to be readily available for this sort of project but as discussed here has virtually been displaced by mdf. It's lighter and stiffer than mdf but not as stiff as solid oak. The shelves are all 1180 mm (46½" ) long and 240mm (9½") deep. (The width was as much as could fit in the alcove and still allow access to a power socket. The depth was just enough for large format books.) 
At the front edge of each shelf there's a strip of solid oak, about 19mm square. This was glued on (PVA, no pins) planed flush to the shelves and then worked with a scratchstock to make the decorative edge. The shelves are completely full, with paperbacks on the upper shelves and heavier hardbacks on the lower ones. 

The shelves do sag a bit. I think it's just the right side of what is acceptable - but I don't really want to start over again on this piece from over 20 years ago!

This is an attempt to line the camera up with the lowest shelf






and this is the shelf above it






In this shot, with some of the books removed, you can see that I did what I could to stiffen these two lower shelves, by glueing and screwing a couple of oak battens underneath at the back. 






The battens are quite small, because that's the wood I had to hand at the time, and because anything bigger would have reduced the space for the larger books, which go right to the back of the case.

I could also have put some intermediate supports onto the back, but it's only lightweight T&G pine cladding and I thought it might bow out a bit or spring out of its bottom rebate if there was too much vertical load on it, so I never did that.

The upper shelves don't have battens but don't really need them with their lighter loads.






I think if I was starting on something this size now, I'd just spend more and get solid oak for the shelves. At the time, I was trying to avoid spending cash - indeed, the whole piece was made possible when I rescued a stack of oak skirting boards from a skip.

While the books are out of the way, here are a couple more pictures of the sawtooth rack arrangement.











The support system is plenty strong enough, even though it's only about 9mm (3/8") thick. I think it's important to decide where you want the shelves to go and make sure that you plan for the final positions when you decide the size of the steps. Once it's all finished and the shelves are in, nothing will ever get adjusted again. Having the shelves demountable is more for the convenience of making the whole piece without wrestling all those ends into place at once to assemble it, and to make it more manageable to pick up.


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## AndyT (6 Apr 2019)

Deadeye":3ipv1krf said:


> Is anyone else secretly looking st what books are on the shelves as much as at the shelves themselves..?



I would!


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## woodbloke66 (6 Apr 2019)

Andy, those shelves look to be about a metre or possibly a tad longer? It's a good looking bookcase and shelf arrangement, but I don't think for moi personally I could live with shelves with even that small amount of sag...it would irritate me beyond belief; nearly as bad as having a shelf on a wall that's not dead horizontal :twisted: 

I'm coming round to the idea of using solid pine shelves, say 23mm thick, lipped all round with oak and then veneered both sides with 2mm bandsawn veneer, so total thickness would be around 27mm. I'd need to buy the pine in good time to let it dry or I could use quarter sawn, stack laminated boards which would be more stable but a bit of a 'faff' to make - Rob


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## marcus (6 Apr 2019)

Crikey it’s a while since I got a UK workshop email popping into my mailbox! Nice to see so many of you still chipping away. 

FWIW I found that thick birch ply (long grain, obvs, with hardwood lipping glued with a spline) 7/8 or even 1” was very stiff and never visibly sagged in any shelf I used it for. 

Absolutely no rule of thumb to offer though, I used it and it always did the job is all I can say. Not the cheapest option though....


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## AndyT (6 Apr 2019)

woodbloke66":1la9vnrg said:


> Andy, those shelves look to be about a metre or possibly a tad longer?



1180 mm Rob!

And as a diy grade woodworker, busy with a young family back then, my standards were not up to yours now!


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## woodbloke66 (6 Apr 2019)

AndyT":1o4pytm8 said:


> woodbloke66":1o4pytm8 said:
> 
> 
> > Andy, those shelves look to be about a metre or possibly a tad longer?
> ...


Thanks Andy. I found the Sagulator last night very informative but as it's 'murrican, it's a bit tricky to work out some of their definitions of man made board material - Rob


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## Demusss (6 Apr 2019)

You could glue a strip across the front of the shelf which is thicker than the shelf. This would help prevent sagging.

Sent from my SM-G965F using Tapatalk


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## MJP (6 Apr 2019)

I'm a bookseller and twenty years ago I built a couple of dozen six foot tall bookshelves from 7" by 1" PAR pine. 
30" wide shelves, screwed and glued into rebates in the side supports, no backing. The only protection against racking being a 3" wide kick strip below the bottom shelf.

These shelves have been filled with mainly hardback books (hefty technical stuff) for two decades and show no visible sag.

I think that 30" is about the limit before sag begins to show.

Martin.


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## woodbloke66 (6 Apr 2019)

MJP":lwdmqgeh said:


> I'm a bookseller and twenty years ago I built a couple of dozen six foot tall bookshelves from 7" by 1" PAR pine.
> 30" wide shelves, screwed and glued into rebates in the side supports, no backing. The only protection against racking being a 3" wide kick strip below the bottom shelf.
> 
> These shelves have been filled with mainly hardback books (hefty technical stuff) for two decades and show no visible sag.
> ...



That follows my train of thought. However, have a swift look at the Sagulator and punch in some numbers. You can, I reckon (not sure here) go to any reasonable length before sag is apparent, provided you choose an appropriate material with a commensurate thickness (which might include lippings) and select the load that the shelf is meant to carry - Rob


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