Shelves depth for workbench - Page 1
Forum section: electronics / beginners

author: jimjam
author_rank: Regular Contributor
timestamp: May 31, 2014, 09:27:31 am
content: I am setting up my workbench using an existing office desk. The dimension of the desk: 180cm (70.8") wide and 90cm (35.5") deep. I would like to put shelves at the back of the desk against the wall. I'm not sure yet what type of construction, but I'd try to avoid damaging the wall so something that would just sit on top of the desk would be ideal. I am hoping I can find something ready made somewhere.What depth should I reserve in order to put things like benchtop DMM, power supplies, etc? I don't have any of those at the moment but I'd like to plan for the futureThis would help me when looking for the shelves.Here's a picture of the desk right now:

author: GeoffS
author_rank: Unknown
timestamp: May 31, 2014, 10:51:45 am
content: This stuff (Shelvit) or its generic equivalent, is great for adjustable shelving. Just use lengths of DAR pine or MDF/melamine for the shelves.As you don't want to damage the wall, you would need to make up a timber/steel frame on which to mount them. The frame would need feet to stop it tipping forward, these could be spaced to suit the legs on the desk so they're not in the way while you're working.For ideas, check out the local storage specialists such as Howards Storage World.

author: jimjam
author_rank: Regular Contributor
timestamp: May 31, 2014, 11:33:05 am
content: Thanks for the idea Geoff. I think I'd need to "build" one myself with stuff like that Shelvit. I'm thinking a board for the back against the wall, and I can mount the shelvit posts onto it. I have a rough idea how to do it now. I'll go check out Bunnings tomorrow because they can custom cut the board for me.I might just have to look up the depth of various stuff like Rigol DP832 and some DMMs to determine my shelves' depth.

author: GeoffS
author_rank: Unknown
timestamp: May 31, 2014, 11:49:21 am
content: A board may not be stiff enough to hold a reasonable load without bending. 18mm would be the thinnest I'd go.You'll still need feet on it sticking back into the room to stop the board from tilting forward when loaded. I had this happen to a friend when the weight of stuff on the board mounted shelves got too heavy and the board just tilted forward, pushing the desk out of the way. Fortunately not loaded with anything expensive, just heavy.Can you put a couple of suitable fasteners into the wall to stop a panel tilting?

author: SeanB
author_rank: Super Contributor
timestamp: May 31, 2014, 12:00:42 pm
content: You probably are looking for 1.2m ( 4 foot) width for the desk, so that your shelving unit can be 0.6m ( 2 ft) and rest on it. That way you can have some deep equipment ( like CRT scopes) on it, and still have space to work on in front. Stiffest shelving is using regular shutterply as shelves, with a back of shutterply ( can be half the thickness provided you have a few screws on each shelf) with sides and a mid brace to spread the load to the desk. The top of the desk will need to be reinforced, as most will bend under the load unless they are reinforced with a dummy shelf a little wider than the shelf. Add a front edge to each shelf ( basically a 5cm wooden brace glued and screwed to the shelf) to reinforce it.I made some at work, and they are strong enough that I can walk on them if needed, as I had to make a set of shelving to hold heavy boxes in a staging area. There I used aluminium U extrusions as both the front brace and as the joins, along with using it to hold the back to the wall. 22mm extrusion was just big enough to hold a nominal 19mm shutterply board with a little persuasion to make it fit, then drill through the alloy and use a lot of 42mm drywall screws to hold the lot together. Then a quick sand down to get the rough spots off and a coat of suede varnish to finish it. Cost was minimal, and I had the drawing so I could get the sheet cut to size ( no charge) at the wood merchant. I had some spare sheet, so also made a set of A4 paper trays to go with it.

author: GeoffS
author_rank: Unknown
timestamp: May 31, 2014, 12:18:59 pm
content: One problem in mounting a set of shelves on the desk is that you lose valuable desktop space.If possible, mount them on the wall or that isn't possible, a floor mounted stand as previously suggested.

author: fcb
author_rank: Super Contributor
timestamp: May 31, 2014, 01:53:34 pm
content: Pull your desk out from the wall and put a cheap set of book shelves behind it.

author: jimjam
author_rank: Regular Contributor
timestamp: May 31, 2014, 02:33:31 pm
content: Thanks for the great ideas and the little details that I hadn't thought of (such as having a front edge for reinforcement).Using bookshelves behind the desk would be nice and easy, but bookshelves are generally not very deep. My bookshelves depth is only 28-29cms (11.5"). A Rigol DP832 as an example, is 42cm (16.5") deep. An Agilent DMM is even deeper. I guess the deep stuff can just be on the desk, not on the shelf.Do people mostly just secure their shelves onto the wall?Time to watch some more of Dave's videos to see his set up!

author: SeanB
author_rank: Super Contributor
timestamp: May 31, 2014, 02:40:00 pm
content: Dave used shelving units that allowed him to make a desktop on a portion, and this is no longer available. You can look at industrial racking, as this will be flexible and then you can simply go buy a postformed desktop sheet to use with it. If you look at your local kitchen suppliers they might have a top from a remodel that is only a little worn, and which will still give sterling service as a desk top and workbench. I made a worktop from a chest of drawers and a postformed top, and it worked well for years. I just screwed mounting angles to the bottom and had the top offset so I could sit under it with no problems. It did not bend under load at all, being 50mm thick Formica laminated board.

author: jimjam
author_rank: Regular Contributor
timestamp: May 31, 2014, 03:47:21 pm
content: Something like this might work well:http://www.custom-products.com/Industrial.nsf/get/Image-Default-EVOLUTION/$FILE/Evolution-Blue-Med.jpgIn fact it can totally replace my desk.

author: edpalmer42
author_rank: Super Contributor
timestamp: May 31, 2014, 04:25:16 pm
content: Quote from: jimjam on May 31, 2014, 02:33:31 pmIf bookshelves aren't deep enough, go to the hardware store and buy a set of heavy-duty adjustable steel shelves. Here in Canada, you can get them 40 or 45 cm. deep with a load rating of 200 kg. per shelf. Use a minimum number of shelves in the lower area that's between the desk and the wall - just enough for stability. Put the rest of the shelves closer together than usual in the area above the desk. You might even be able to place one shelf at the level of the desk and use it as an extension to the desk.Ed

author: jimjam
author_rank: Regular Contributor
timestamp: May 31, 2014, 05:16:55 pm
content: I've just found yet another solution. These are called Gondolas, used by retail shops:For example:http://img.bosscdn.com/photo/product/43b8aebea6cd006c3fbab10279949bf5/shop-fixture-for-island-gondola-shelving-paper-floor-stand_360x360.jpg

author: GeoffS
author_rank: Unknown
timestamp: May 31, 2014, 05:22:10 pm
content: The godolas would get in the way of your feet under the desk.

author: leppie
author_rank: Frequent Contributor
timestamp: May 31, 2014, 05:51:35 pm
content: Mine is 450mm, Tek 465 and TDS340 fits on it just just. And those are pretty big scopes. Right angle plugs help too.

author: Matje
author_rank: Regular Contributor
timestamp: May 31, 2014, 10:31:15 pm
content: Quote from: jimjam on May 31, 2014, 09:27:31 amAs a datapoint: my desk has a depth of only 70 cm, so not much space. The shelves are 28 cm deep, which I feel is the minimum useful value. It is enough to hold power supplies, soldering and hot air station, digital counter, sig gen, DSO etc. and even a HP 34401A DMM, although that one protrudes a bit at front and back (desk is not flush against the wall).I think in your setup between 40 to max. 50 cm would be OK. You might study the mechanical specs of common devices to get a feel for what you want.I have to study these to find out what I can actually fit... ;-)

author: jimjam
author_rank: Regular Contributor
timestamp: June 01, 2014, 06:26:24 pm
content: I played around with "Sketchup" software (freeware) to come up with this diagram of the bench design. Any feedback regarding the depth / heights of the shelves please?The desk is an existing desk. I am just building the shelves, i.e. the part above the desk.Is it a sound design? The thickness of the board will be 25mm and I believe should be strong enough to span the entire 180cm width without bending I hope. It is supported on the back but not on the front. If necessary I can install some kind of support on the front too.

author: Mark Hennessy
author_rank: Frequent Contributor
timestamp: June 01, 2014, 07:20:44 pm
content: I did a similar thing, but I made the top shelf deeper than the bottom shelf (330mm and 530mm). Then, I put a light fitting under the top shelf, which does a good job of casting light onto the bench.It works well because in practice, kit is a mixture of deep and shallow.To prevent shelves bending under the weight (which they will, even at 25mm), I added vertical sections which joined the two shelves together. But my design has a rear panel as well - if yours is open, then perhaps this won't make much difference.Now, a rear panel can make access difficult, but my desk is on heavy-duty castors. This rear panel runs from the bench top to the top shelf, so I can easily access the rear of the deep stuff on the top shelf. It works really well.The top section is divided up into 19" bays, each of which is 6U high. The whole thing is just over 7 foot wide, meaning that I have four of these. Whether this is worth doing depends on the gear that you have, but it does work quite well for me.I would have made mine taller, but the headroom is limited in my cellar workshop.Haven't yet got around to writing up the project, but here are a couple of work-in-progress pictures...Good luck with yours,Mark

author: jimjam
author_rank: Regular Contributor
timestamp: June 02, 2014, 01:09:56 am
content: OMG MARK, Yours is SO BEAUTIFUL!I am IN LOVE!!!!! Thanks for the great inspiration! I was planning on just dropping cables to the floor and have a power board there but your idea is brilliant! The only problem is that my desk isn't easily moved (no castors), but I guess once it's all set up, I can just push it up against the wall. Having the electricity outlets all there would make life easier. I wonder if the outlets need to be installed by a licensed electrician here in Australia.... (I'm not one).Can you tell me the heights of each shelves please?I'm thinking that the first shelf needs to be deep as well so that I can put a long PSU in it, but that would severely reduce the desk space.

author: nanofrog
author_rank: Super Contributor
timestamp: June 02, 2014, 01:16:37 am
content: Quote from: jimjam on June 01, 2014, 06:26:24 pmShould work IMHO.Depth is a bit deeper than I like (mine is 30"/~750mm deep, and not quite as wide 60"/~1500mm), but mine was built to be used with a chair, not a stool (can't lean forward as easily to reach that extra 150mm well). Went with adjustable shelving so I can change it as needed in the future.FWIW, I used steel angle to help with sag (along with the middle bracket support for full width shelves). It also acts as a lip so equipment can't be pushed/pulled off easily (feet grab the lip; though not in the pic, there's one on the back edge of the shelf as well). Also not in the pic, is pegboard for the rear (between the bottom & middle horizontals), and the gap at the bottom is left open for access to the power strip. Drawers too, salvaged from a damaged metal desk.BTW, damaged & used office furniture as well as used restaurant furniture are inexpensive sources for well made tops (drawers as well from office furniture). Saved me a small fortune going this route (i.e. paid $50 for the damaged desk, and was able to use all the drawers <2x separate drawer units> as well as the top).

author: JFA
author_rank: Regular Contributor
timestamp: June 02, 2014, 02:45:51 am
content: Small world! I am considering getting shelves for my desk too.I did not find ANYTHING that would carry a large load, that is self-standing, and that I would trust with my pricey equipment, and that had the functionality that I need. Dave's shelving is nice, but Ikea does not make it anymore.I am seriously considering buying square steel tube 1" x 1/16th or 1/8th wall, fit a cutting disk to the angle grinder, and fire up the MIG welder...

author: GeoffS
author_rank: Unknown
timestamp: June 02, 2014, 02:54:48 am
content: Quote from: jimjam on June 01, 2014, 06:26:24 pmDesign looks good, doesn't impact on desktop space too much.For calculations on the amount of sag you'll get, take a look at theSagulator.

author: nanofrog
author_rank: Super Contributor
timestamp: June 02, 2014, 03:18:00 am
content: Quote from: JFA on June 02, 2014, 02:45:51 amI used 1-1/2" angle (1/8th wall) to build what's in the picture. The upright frame is bolted on to the back table legs and the rear cross member the top is mounted to instead of welded (disassembly for moving). Adjustable shelving uprights/rails are also bolted on (for replacement should they need changed/replaced). Everything else is welded.The second bench frame was made out of 1" square tubing (wall thickness is 14ga, which was the heaviest offered). No pics yet. Great for the table frame, but wouldn't use it for the single upright design I opted for (upright is 48" off of the table's top, so it would have leaned forward too much for my liking). Might want to go for larger tubing, say 1.5" or *possibly* 2", if you something similar.For cutting, I used a metal cutting blade (abrasive type) in my 10" power miter saw. Made easy work of it, particularly as I used 45* cuts in a few places (would be more accurate than a grinder if you have one or access to a friend's).Another little trick I added, was to weld in a 1/2" nut inside the bottom corner of each leg (cheap adjustable height legs).Couple of extra picsuploaded FWIW.

author: bingo600
author_rank: Super Contributor
timestamp: June 02, 2014, 04:41:05 am
content: @MarkThe "switchbox" top right , is that controlling your 230v outlets ?I mean the orange vires in the back ?Did you use relays inside it , or ?TIA/Bingo

author: jimjam
author_rank: Regular Contributor
timestamp: June 02, 2014, 08:20:22 am
content: Inspired by Mark's design, I've revised my design. I'm still not sure how high my first and second shelves should be. It would be easier if I already have the power supply and oscilloscope etc. so I can physically lay it out.The vertical support on the back should make this design much stronger. I'm still a bit worried about the front. I will see if maybe there could be a suitable metal support can be used, otherwise I'll have to use a thin strip of board like what I do on the back, horizontally.

author: GeoffS
author_rank: Unknown
timestamp: June 02, 2014, 09:41:47 am
content: Quote from: jimjam on June 02, 2014, 08:20:22 amIf you make the horizontal sections (where the power points are) out of the same material as the shelves, then you won't have any problem with sagging.You just have to make sure that the shelf unit is firmly attached to the desk so that it doesn't tip.

author: VK5RC
author_rank: Unknown
timestamp: June 02, 2014, 09:54:07 am
content: I used something similar to this pallet shelving, saved a lot of welding/grinding/painting, serious load capacity and flexibility. I thought good value for money.I have a desk to the side, with a little bit of shelving on it as well.http://www.ebay.com.au/itm/PALLET-RACKING-WAREHOUSE-SHELVING-2438mm-HIGH-FRAME-8-TONNES-RATING-/350790753413?pt=AU_Business_Industrial_Retail_Shop_Fitting_Supplies&hash=item51acc21c85&_uhb=1Bit industrial mind you but if something is at the back of the rack I am happy to climb on the structure!Robert

author: GeoffS
author_rank: Unknown
timestamp: June 02, 2014, 10:07:44 am
content: Bunnings sell something very similar to that eBay stuff. It's a modular racking system called 'Rack It'Just mix an match the bits you need.

author: con-f-use
author_rank: Unknown
timestamp: June 02, 2014, 10:53:06 am
content: Quote from: Mark Hennessy on June 01, 2014, 07:20:44 pmI want to have your shelf-babies!

author: Mark Hennessy
author_rank: Frequent Contributor
timestamp: June 02, 2014, 11:34:51 am
content: Quote from: jimjam on June 02, 2014, 01:09:56 amThanks for the kind wordsRegarding the height of the shelves, the lower one is 330mm above the bench surface, and the upper one is 695mm. This is the height to the surfaces. The bench surface itself is at desk height (710mm), and is 900mm deep. The surface is solid oak flooring (very nice), and I use a large cork mat to protect it - and bits of carpet if needed to protect gear from getting scratched. In a humid cellar, static is less of a worry...As mentioned earlier, I have limited height in my cellar, so everything was a bit of a compromise. In myprevious workshop, which was in a garage, I put it at bench height (around 900mm IIRC), and the shelves were a bit more generously spaced. So this really was an attempt to make the best out of a bad situation, but it has worked quite well in practice.The height of the first shelf is dictated by my favourite analogue storage oscilloscope (theTelequipment DM63). When determining the position of the top shelf, I worked down from the ceiling height (less a bit for safety), deciding that 6U (267mm) would give the best compromise. I have about 11-12" of usable height on the lower shelf - the 4" support timber and hidden lighting obviously being a factor there.Behind the (largely decorative) hardwood plank (100mm by 20mm) is a "4 by 2" joist that takes the worst of the weight. The side panels transfer the load down to the bench surface. That joist had to be cut down to fit, and it had a 45 degree section removed so that it didn't shadow the output of the light. It does seem pretty solid. I used 18mm spruce ply for the shelves/sides/rear/etc. It's cheap and not very nice, but strong. MDF is no good in a cellar, even a relatively dry one like mine.There is another shelf under the bench - you can see the 4 by 2 that supports the leading edge. This is 420mm deep and 330mm off the ground, and is used for storage. I also have a couple of SFF HP PCs under there, nicely out of the way. A Belkin KVM allows me to switch between them, and I also use that for hooking up PCs that need time on the bench. Very useful.As for the electrical installation, the whole desk plugs into a single 13A mains outlet, and is protected by the 13A fuse in the plug. So from a legal point of view, it's an "appliance", not an "installation" - little more than a glorified extension lead - and as such, is immune to electrical building regulations.The die-cast box contains a DIN mounting rail which carries some terminal blocks, an RCD, and a 3.15A fuse for the light.Look to the right of the 'scope, and you'll see 3 switches. The bottom one is the light (with a 0-10V dimmer), next is the white switch for the white sockets, and the top one is the red switch for the red sockets. The red sockets are intended to be left on 24/7, and are primarily for the computers.In addition to the red sockets, there are 11 double sockets on the rear wall of the bench, and a double on the rear, just above the die-cast box (not shown on the picture) - this is for the 19" MDU (mains distribution panel) which powers all the stuff on the top shelf. This has 12 outlets, all individually fused at 3.15A.A useful tip - all those sockets on the rear are hard to get to because the test equipment obscures them, and I didn't really think about that at the design stage. So I found a 19" rack-mount MDU that had conventional 13A outlets on the front, and mounted it in the right hand bay, along with thedual isolating transformersthat I made a few years back. I modified the MDU to include a cheap eBay mains voltage/current monitor (although I had to seriously re-engineer that - another story!), and included a couple of BNCs so you could (safely!) see the voltage and current waveforms. Finally I added a 10 thermal breaker. I'll attach a picture - although it's had a paint-job since then...The RCD only protects the white sockets, in the hope that the computer gear wouldn't be disturbed by an accident on the bench. I really recommend having an easily accessible "breaker" breaker for all the sockets, as it makes things so much easier and safer. Should smoke emerge from something, you just want to hit the "panic" button! You might choose to use the RCD itself as the daily power switch, but as the RCD is quite large, I thought it was better to hide that around the back and use the 20A double-pole switch on the front.It does seem like an awful lot to hang off a single 13A plug socket, but the current demand is pretty low most of the time. Heavy items like heaters and power tools get plugged into other sockets in the cellar; the bench is for low-powered test gear and "items under test".Sorry this is such a long post, but I hope it helps to answer some questions and perhaps give some ideas. I will write it all up on my web site one day soonAll the best,Mark

author: idpromnut
author_rank: Unknown
timestamp: June 02, 2014, 12:57:11 pm
content: @Mark: Holy freaking beautiful workbench batman!I am deeply, deeply envious

author: jimjam
author_rank: Regular Contributor
timestamp: June 05, 2014, 12:38:23 pm
content: Finally, my shelves are done! I can now start playing with electronics. The shelves are independent from the desk. It just slides over it.

author: GeoffS
author_rank: Unknown
timestamp: June 05, 2014, 12:48:36 pm
content: Excellent solution!