Custom bench for electronics lab, using T-slot extrusion frame - Page 1
Forum section: electronics / projects

author: TiN
author_rank: Super Contributor
timestamp: January 12, 2020, 05:47:57 am
content: Got tired of piling equipment on top of each other, so it's time we have nice bench to make everything neat and organized.Since my woodworking skills are non-existent, decision was made to go with T-slotted aluminum extrusion to work as a structural frame, with plywood/MDF sheets for shelf and bench-top surfaces.After trying multiple iterations, here's somewhat final variant.This frame will carry all the weight and loading. About 80 meters of extrusion, ~150kg.Estimated layout:Many standard benches don't have enough depth to put full-size test equipment, such as calibrators, network analyzers or even just high-end oscilloscope and still leave enough area in front to work comfortably on DUTs/boards. This design supposed to solve this issue, with 1.5m deep main level working area, and additional 1.35m deep shelf for stuff like power supplies/scanners/standards/aux gear.Here each 2 meter long section shown leveled, but actual design is flexible, and each surface can have own level to fit specific use/project.Ideas? Suggestions?

author: beanflying
author_rank: Super Contributor
timestamp: January 12, 2020, 08:33:28 am
content: Just to throw a complete spanner in your design I would have used 3060 or even 4060 rather than the 45x45 you show. The deeper profile should tend to give less deflection on any shelves.You might get some ideas from this recent Laser build on fittings, cutting and basic drilling and tapping for assembly of T slot. Worth a watch regardlesshttps://www.youtube.com/channel/UCZ72zDm2feverqV7qAbNH7Q/videosAlso if you are planning on cutting your own shelves a Track Saw is a very worthwhile tool to add to your collection.

author: awallin
author_rank: Frequent Contributor
timestamp: January 12, 2020, 08:53:24 am
content: any plan for how to place AC-outlets and run all the AC power cords (+possibly Ethernet switch and cords to all instruments?)lights? will it be dark in the work area under that wide shelfshallow and wide drawers under the working-surfaces? for e.g. SMD organizers (mini-boxes)? or keyboard/mouseI'll take a 2-module wide unit, with oak surfaces please

author: H.O
author_rank: Frequent Contributor
timestamp: January 12, 2020, 09:07:03 am
content: Massive bench! Are you going to anchor the backside of it to the wall? If not I think you'll need some bracing.Depending on the type of fastners used to attach the pieces to each other you might want to add some brackets to support the horizontal pieces onto which the worksurface rests. I know I wouldn't want that thing to colaps on me.I take it you're ordering the pieces cut to length?And, as has been mentioned, I would look into how much sag you'll get on a 2m long 45x45 but it sounds like you might already have done that.Looking forward to see the build!

author: Muttley Snickers
author_rank: Unknown
timestamp: January 12, 2020, 10:00:46 am
content: The shelves on my twenty year old storage racks are 1800 x 600 and rather than use MDF or Plywood I used Melamine instead as it was easy to keep clean, not affected by surface water and less prone to warp. Price wise it was about the same as the other options anyway. For those not familiar melamine is laminate covered particle board as used in kitchen cupboards.

author: PTR_1275
author_rank: Frequent Contributor
timestamp: January 12, 2020, 11:19:07 am
content: Looks good TiN. It would be easy enough to put in extra braces under the shelving where needed too. I would be a bit hesitant having that much weight on such a large area of shelf without extra support under them to stop bowing.Looking forward to seeing how it all ends up

author: nctnico
author_rank: Super Contributor
timestamp: January 12, 2020, 11:24:21 am
content: @Tin: You'll need to add ways to make the frame stiff (like closing up the back and sides at least partly) otherwise the whole thing may flex and even fold / collapse in on itself.

author: Renate
author_rank: Super Contributor
timestamp: January 12, 2020, 12:36:52 pm
content: Melamine is too thin for my taste.I had a cheap desk that used that and it gouged pretty easily.The layer can be as thin and cheap as shelf paper.For a work bench (or even just a desk), I suggest Formica (TM) or other plastic laminate.They are tough and don't mind alcohol or the occasional solder blob.You need to contact cement it down, route the edges.You can either use plastic edging hammered into a slot or laminate them too.A 2 meter span is large.It would complicate your multistage design, but for many of your positions you could do it differently.You could have supports every meter (with an offset of 0.5 meter).This would leave a clear one meter section in each position for your legs.This would also compartmentalize areas for storage on the bottom, drawers, cabinets, whatever.You've got a lot of space there that is not being used.You could dispense with the whole top layer of your design.I'm a big fan of 1" square aluminum tubing.For vertical members it's plenty strong.They also sell it with slots so that on the bottom you could add "vanity panels".Even a 1/4" panel in the assembly adds a lot of rigidity.https://www.mcmaster.com/structural-framing/=25f3da55d1bc41db84542ac8f5749febk5azxob1I'm typing this on a two meter desk with four legs a meter apart, 3/4" plywood with laminate, two side panels of 29" x 24".

author: Kleinstein
author_rank: Super Contributor
timestamp: January 12, 2020, 12:57:34 pm
content: Near 2 m span is quite a lot with heavy instruments / supplies. So there can be quite some bending.I would not like the beam or full depth board in some 1.7 m high over the desk. It probably would not take long before it gives you a headache.One would have a hard time to use the full depth of the upper boards anyway.For stability some diagonal connections are needed, unless firmly bolted to the wall.

author: Muttley Snickers
author_rank: Unknown
timestamp: January 12, 2020, 01:10:37 pm
content: Quote from: Renate on January 12, 2020, 12:36:52 pmI suspect that there are different grades which all fall under the name of Melamine, the stuff I used is 16mm thick and has a slight grain or textured surface which has stood up well to all sorts of abuse.

author: wraper
author_rank: Unknown
timestamp: January 12, 2020, 01:13:00 pm
content: IMHO not recessed top shelves will suck big time. Besides all obvious downsides like obstructing view and accessibility of any equipment standing on it, it will also block light coming from top. So you will be working in a sort of dusk. If you add local lighting, it will sit in front of your eyes, partially shining directly into them. Decent lighting should be way above your head.About monitors, sitting in the middle of tho monitors placed under angle is not good in my experience. You won't be able to observe both of them simultaneously anyway. And to switch from one to another you will need to turn your head. As both of them are in sub-optimal position, it will suck even if you choose the main one. You'd better sit in front of one under straight angle. Second monitor placed under angle for secondary tasks, on the left side if you are right handed. Not to say 43" may be way too big. Don't suggest going above 32-34" unless you really tried this in practice and find satisfactory.

author: ogden
author_rank: Super Contributor
timestamp: January 12, 2020, 01:39:59 pm
content: I would use generic electronics lab shelving, without structural elements dividing work surface into strict sections.Like in this TI video. Also good idea to make heavy system supplies mobile - put them below table, on trolley(s).  Don't forget "service" PC for rework/assembly area. It could be small netPC with 22" LCD on articulated arm.

author: Yansi
author_rank: Super Contributor
timestamp: January 12, 2020, 01:46:09 pm
content: Quote from: nctnico on January 12, 2020, 11:24:21 amIf he is supposed to make it from the industrial strength grade Alutec like we use in EU for building industrial equipment with, it won't budge. Maybe couple mm if you sit in the middle of it.Pretty hefty stuff, also VERY expensive.According to a calculator provided from one manufacturer I am used to, a 2m long section will budge just 5.8mm at 100kg load in the middle. I'd say good enough. You will never have that much load on it.

author: RoGeorge
author_rank: Super Contributor
timestamp: January 12, 2020, 02:08:59 pm
content: The design looks great!That's exactly how I have it organized, mine is only 3 benches with shelves above, and chairs at bench 1 and 3:- first bench with the PC monitors- second bench the instruments (oscilloscope, generator, power source, etc) so they can be operated from either bench 1 or bench 3- third bench is for soldering tools, microscope, etcStorage is everywhere in the room, and some other shelves on another wall.What I miss is a monitor on the 3'rd bench, to keep a schematic or a datasheet display while working, but it will cover the storage shelves, so I'll not put another monitor there unless I'll found a good and strong suspended boom arm for a small monitor.The biggest drawback for now is the window is on the left side, so natural light is at the first desk instead of the 3rd, exactly opposite than how it should be.To me, a circular cutting in the middle of the desk would be a big disadvantage, since many times I end up having the board I'm working right on the near edge of the desk.

author: Renate
author_rank: Super Contributor
timestamp: January 12, 2020, 03:05:58 pm
content: Quote from: wraper on January 12, 2020, 01:13:00 pmI agree! You are always just looking at the crack between them. That's why I have three.

author: jogri
author_rank: Frequent Contributor
timestamp: January 12, 2020, 03:56:19 pm
content: Have you ever worked on a 1.5m deep bench? Even if you have full size, 50-60cm long test gear it would be uncomfortable to use it: You can reach 70-80cm without leaning forward, and if you have 1m between you and your gear you are going to hug your DUT every time you want to adjust something.The same problem applies to your cold storage, you won't be able to reach most of it without using a ladder.Btw, you should probably screw down the legs, should be rather easy if you install a 90° angle and screw it to the ground before dropping in the horizontal beams.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: January 12, 2020, 04:09:15 pm
content: Seems like a good way to go if cost is no object. At work we build a lot of things out of Minitec rail and it's strong as heck. It helps that the Minitec warehouse is only a few miles away. Good ideas above. I had my (wood) bench built deep, but only about a meter. That's enough for my boat anchor HP meters and stuff. Deeper would be a problem. I have some holes in the back with plastic inserts for power cords but integral power strips might be better if they had enough outlets. Agree about the shelves above killing the light.

author: TiN
author_rank: Super Contributor
timestamp: January 12, 2020, 04:16:35 pm
content: Wow, lots of feedback. To reply on some of concerns:Stuff on top shelf would be rarely needing front panel/knob access. Part of the reason is that everything in lab interconnect via GPIB or LXI bus. So far I often find large gear like PSU or parametric analyzer occupy valuable working area space while running days long experiments. Some of my gear need 63-65 cm depth, plus cables plus space for airflow for cooling fans.Moving gear out can help to resolve this issue.LED panels would also be installed on top shelf's inside surface,as well as ambient lights. LED panels, such as 60x60 cm ceiling type are one of reasons why I thought to make top shelf as deep. To mount light out of sight if one sits in normal position, looking forward.Top shelf perhaps bit too wide, so I'll see if it's better to reduce it slightly in. I was hoping to keep frame like a box tho for better integrity. Most of heavy gear will live on working bench level.For monitors, I spent a decade with 30+24 or 30+20+20 setups until moving to single 43" 4K monitor. Day and night improvement, life without bezels and 4K resolution with Windows scaling 100%. 32-34" is just too small for 4K. There will be small 24" FHD screen in assembly/rework area. And fume extractor as usual.AC power cords, Ethernet cables, switches, UPS stuff, all that will go to top shelf. Only smaller power distribution board would be installed on two middle sections for daily work.I don't draw all that yet, as it would be Phase 2 of the project, when refining apply.I am rather tall person (almost 2m) so large legroom space is paramount for me. This means no drawers, no shelf or anything like that under the workbench. Hate to bump into stuff when move from one side of the bench to another.

author: RoGeorge
author_rank: Super Contributor
timestamp: January 12, 2020, 04:30:21 pm
content: The depth from the front edge of the desk to the instrument's front panels (or upper shelves) in my benches is about the length from the elbow to the tip of the fingers, and is a little bit too much. Making it even deeper will be very uncomfortable to use.About multiple monitors, I noticed that having 3-4 of them doesn't really make one more productive. I prefer one big (32'' 4K or bigger right in front, and one lateral smaller monitor on the left. The left monitor is only rarely used, a big diagonal 4K or so can display more than enough windows to work with.Having a 3rd monitor on the right side is not an option for me, it will stay in the way while fiddling with the instruments or with the device under test while staying at the PC.

author: Brutte
author_rank: Frequent Contributor
timestamp: January 12, 2020, 04:43:59 pm
content: Quote from: TiN on January 12, 2020, 05:47:57 amI do not like the concept, because:1. The 2m wide span requires a stiff beam to span under your MDF. You have decided to put this stiffening beam just above your thighs.Take a piece of that extruded beam and glue it under your current desk, just near the edge. Any conclusions?2. Putting vertical supporting legs just in between sections is also unfortunate. You cannot move from one section to the other without sliding out the chair and bypassing it.3. This design has very low stiffness for any shearing forces. It will collapse under its own weight. You have to redesign it.4. I suggest you should think over the way this construction behaves on overload. If it collapses by plastically straining one member and then stops then it is fine. However, if the design is to fall apart completely on failure of single connection then I would not use it to keep my gear there.How about fastening some trusses to the back wall?

author: SparkyFX
author_rank: Frequent Contributor
timestamp: January 12, 2020, 04:46:20 pm
content: The overhang top shelf is great to install lights underneath and have good workspace lighting. However you need to consider using connectors between the beams likethese, they lock into the slots and stabilize the construction sideways.

author: TiN
author_rank: Super Contributor
timestamp: January 12, 2020, 04:48:18 pm
content: Yup, there will be double angle connectors, with 4 bolts on each junction side. It's just not shown on 3D model. As well as feet pad on bottom.BrutteAll sheets are supported by square beams right under. So I don't quite get the number 1 item. For item 2 I don't see any reasonable solution otherwise, since total length is 8 meters, and load on main bench would be about 400kg.

author: TiN
author_rank: Super Contributor
timestamp: January 12, 2020, 05:36:06 pm
content: To go back in time, back 10 years ago, I had similar idea bench but much simpler in construction and design. It used vertical beams from hexagon extrusion, and angles to mount shelf and bench.Depth of that bench was 1.1m and it was very nice to use, but I didn't have large instruments like now. Width of segment was 1.37m and there was zero support under. Laminated MDF did sag but bench didn't collapse on me after daily use for 2 yearsI found old images from server for reference:Beams:MDF sectors with laminated surfaceMounting hardwareShelf support:Assembled:Workbench with monitors (Dell 3008WFP + two Dell 2007FP in pivot)Middle shelf.Obviously this design wouldn't survive the new needs, hence I go with much beefier aluminum system and full square supports under working areas, and reduce from 2 shelf to 1 shelf build.

author: free_electron
author_rank: Super Contributor
timestamp: January 12, 2020, 05:53:46 pm
content: nice.i like the cutouts in the workurfacei built mine from three ikea jerker tables that i added in front of breadracks

author: TiN
author_rank: Super Contributor
timestamp: January 12, 2020, 06:27:53 pm
content: Added junction connectors, reduced depth of top shelf and minor tweaks.

author: floobydust
author_rank: Super Contributor
timestamp: January 12, 2020, 07:43:32 pm
content: I found80/20 T-slotexpensive which is OK if I'm getting what I want. But the deciding factor was doing shelving. Just the usual screws and nut and bracket at each corner which cannot take much shear and high cost per joint. Then you need a level and tape measure at each corner. Even complained to the 8020 Co. that they have no decent shelving solution in their ecosystem. The cost per shelf was the project killer for me. $10 per bracket plus screws, nuts and I couldn't justify it.If I was to go further, I would find a way to mountKnape & Vogt (KV) adjustable shelf brackets (pilasters)in the pillars. They are low cost metal strips and at Home Depot etc., and go with with wood shelves.I also complained they have no 80/20 power bar solution because just mounting a i.e.Hammond stripis just too much hassle. I need an extra worth $20 of fasteners per power bar?Get the fasteners from china and save $100's of dollars, or even extrusions on a custom shipment. It can also be cheaper to CNC machine some pillars and use anchor fasteners.In your layout, my knees would constantly hit the pillars on either side of each bay. I would move them back in. You would not have elephants on the shelves. Put pegboard panels in there to hold cables or some tools. Lighting is something else to think about.

author: TiN
author_rank: Super Contributor
timestamp: January 12, 2020, 07:49:54 pm
content: QuoteI will have ~100-150kg (330 lb) constant load on each section, so prefer to overdo in this particular case. Sadly this is was not planned as low-cost project by any means, but lab requirements justify it.After all, this is planned to serve me for years and years.

author: richnormand
author_rank: Unknown
timestamp: January 12, 2020, 08:05:33 pm
content: I did a similar setup in the past. On the back I used stranded stainless steel wire in an X pattern for each section with an adjustment turnbuckle at one end as diagonal tension members.It stabilized and greatly stiffened the whole structure. It also allowed fine adjustments to get the whole thing squared properly and leveled once on the floor.Also do not forget proper ground and and ESD precautions (for the electronics area)As far as sagging shelves under load I used L-shaped "dixion" lengths bolted underneath the shelve. They resist bending very well, are cheap and are available in long lengths. Makes a nice way to mount rack equipment and hang stuff from too.

author: nctnico
author_rank: Super Contributor
timestamp: January 12, 2020, 09:53:38 pm
content: Also think about cable ducting. I have an open slot at the end of my desk with cable trunking underneath.The power distribution is a project in itself.In total I have over 100 mains outlets under my work bench.

author: cncjerry
author_rank: Unknown
timestamp: January 13, 2020, 01:31:30 am
content: how much are those t-slot sections and how much weight can they hold over 4ft span? I have a cabinet that i want to bridge across because the weight of my new spectrum analyzer will collapse the top preventing the top drawer from closing. The cabinet is about 42" wide. I figure if I can build around it I could use the space.ThanksJerry

author: ebclr
author_rank: Super Contributor
timestamp: January 13, 2020, 08:14:14 am
content: This thing is cheap, strong and " programmable "https://www.amazon.com/AmazonBasics-3-Shelf-Shelving-Unit-Chrome/dp/B01M0XLTT5/ref=sr_1_13?keywords=Chrome+Wire+Shelving&qid=1578903111&sr=8-13Make a regular table and put this shelf on top

author: RoGeorge
author_rank: Super Contributor
timestamp: January 13, 2020, 08:55:53 am
content: For "programmable" and zero tinkering, I'll recommend the IKEA ALGOT system. That is what I use now, and since I don't have any boat anchor instrument, it's more than enough. The heaviest instrument I have is a Rigol DP832 power supply of about 9 kg.https://www.ikea.com/ro/ro/catalog/categories/departments/bedroom/22798/In the link there are only suspended rails, but ALGOT has pillars and standing legs components, too, so it doesn't need wall anchoring. So far very happy with it, strong enough, nice look, and can have shelves on the both sides of a pillar.

author: DBecker
author_rank: Frequent Contributor
timestamp: January 14, 2020, 04:51:32 am
content: Quote from: Renate on January 12, 2020, 12:36:52 pmErrrmmm, what material do you think that Formica(tm) is?(Answer: it's a melamine laminate.)Making this relevant:The name ForMica comes because melamine infused paper was originally used to replace mined mica in capacitors and electrical insulators. It's properties are not as good as mica, but it enabled making better inexpensive rolled "paper" capacitors. Real mica is still used in capacitors that must be stable at varying or very high temperatures, while Formica stopped being used long ago.

author: Renate
author_rank: Super Contributor
timestamp: January 14, 2020, 12:36:03 pm
content: Quote from: DBecker on January 14, 2020, 04:51:32 amErm, well, you got me there.Still, looking into this, "melamine boards" are LPL, low pressure laminate.Formica or Wilson Art are HPL, high pressure laminate.I measure what I used on my desktop as 1mm thick.Can somebody tell me how thick the facing on their melamine boards are?Then there is the question of the substrate.I don't like, won't use particle board, it's not good around moisture.(Yes, I know you have facing and banding on it, but liquid can get into the edges and make it swell.)I get a wider choice of colors with HPL and I can band the edges, also curves (as shown in my photo).

author: Shock
author_rank: Super Contributor
timestamp: January 14, 2020, 04:07:57 pm
content: I made a post about surplus Rack PDUs being a viable option for lab power in the below link. In my main 2400mm bay I have up to 48 individually switched outlets. The PDU supports staggered powering, switched groups, shows loading etc.https://www.eevblog.com/forum/reviews/lab-shelf-power-solution/I use long span shelving and it's basically the same thing you are doing but the industrialized kitset version. I have in total about 13 cubic meters plus benches. I've probably spent about $500 all up on it including power and cabling.Not meaning to be rude but the weakness in your design I noticed was lateral movement when fully loaded with an uneven distribution of weight. Front and backwards you are fine but sideways it's a collapsible box depending on if the system is free standing and how the desktop is secured to the uprights.To illustrate this imagine shoving it hard from the side. Hopefully the interlocking system or desktop will hold it from moving sideways but I would put a few diagonals in the lower bottom so that lateral movement bears weight on the diagonals before the interlocks.Anyway here is an image of 600mm deep longspan, you can make it as deep as you like and size the upright support horizontal and diagonals accordingly. As already mentioned shelf sag becomes an issue so to avoid that you they sell horizontal shelf support bars. Shelf heights are fully adjustable.

author: DBecker
author_rank: Frequent Contributor
timestamp: January 14, 2020, 06:13:10 pm
content: Quote from: Renate on January 14, 2020, 12:36:03 pmThere are many types of fiberboard. Low end types act like desiccant-filled sponges, swelling even with modest humidity. Some claim to be rated for moist areas (e.g. residential bathroom cabinets), but they still don't do well with constant water exposure. You want an "enhanced MDF" backing at minimum, not "particleboard". If you require formaldehyde-free products, you may need to compromise on other characteristics such as moisture resistance.

author: rhb
author_rank: Super Contributor
timestamp: January 23, 2020, 05:49:38 pm
content: Interesting thread with some good ideas. In my case I'm building an RF bench rather than a metrology bench, so very different requirements. RF gear is very heavy and requires a huge number of special cables and other paraphernalia.I am just starting on the design of a 16' bench for my new lab area. To provide easy access to the rear of the instruments and wall I plan to have casters under it and toggle legs that lift it off the casters. Very similar concept, though no cutouts and I'll use cabinet grade plywood for the top and shelves rather than MDF.The aluminum extrusion is very nice, but as noted, expensive. Instead I plan to use square steel tubing and angle. Naturally, that will have to be painted. I'm going to cantilever the bench top supports between the end sections. The cantilevers and a few other components will probably be welded, but most things will be bolted to allow for changing requirements.To provider good air circulation full width instruments will sit on angle rather than a solid shelf. I'm also considering baffle panels and muffin fans to pull air through the instrument stack and exhaust it towards the ceiling. Instrument power will be supplied using EMT and flex all the way to the IEC connector as with my current bench. That has proven very satisfactory, though I made the initial instrument feeds a bit short and it's a hassle to reconnect an instrument if I take it off the shelf. The feeds for the new bench will reach all the way to the front of the instrument rack.To address the shear stiffness issues mentioned earlier I'll have solid end panels which will have a 2nd panel mounted on a 100% extension slide which will store test cables. So each bench will have a shallow, full height pullout for cables and adapters at each end.

author: ramon
author_rank: Regular Contributor
timestamp: February 06, 2020, 04:17:12 pm
content: While your design is visually beautiful I think that it is not cost effective and probably not the best option to place your elephants there.Don't know if you already have ordered that massive amount of T-sloted aluminum. My guess is that it could cost at least US $1,800 just only on 45x45 aluminum (according to grainger and misumi prices). Then you will need add another $800 just only in hardware to make joints. And then add another $900 - $1200 for plywood/MDF. All that without shipping cost. If the extrusion is not cut to exact dimensions then just add another $200-$400 for a mitre saw / blade, and expend weeks doing cuts ... and grinding to match all sides !!!.A lot of money - and time - wasted when there are already some cost effective solutions on the market :All production sites use some kind of Laboratory, Packing, Industrial, or just 'steel workbenches' and 'shelving' (nice keywords for google). Of course there is not a complete specific custom solution to the problems that you want to solve, but you can mix them together to get some acceptable solution without not so much money AND time involved.It is basically the same idea that Free_electron suggested ('Ikea jerker tables added in front of breadracks') with the difference that those (industrial steel) workbenches can handle loads between 1000-6000 lbs.Does the top shelf need to be 1m deep? I think that is not a good idea. You would soon won the lottery to start having backbone problems ! Definitely not good idea to place big stuff there. Boatanchors better on separate shelves (unless you use them daily), and if on bench then make sure you have some smart way to move/slide them with ease.Think that you can also place two shelves at the sides of the workbench (with the same deep than the workbench, or shorter) and plywood across shelves to make the top rack. You will need some kind of supports that are already being sold as accessories (check grainger workbenches accessories section). You can check Tennsco 'bulk rack shelving' frames that is actually the same steel framing that Shock have shown.Some links to check pictures and maybe get new ideas:Workbenches:https://www.cisco-eagle.com/catalog/category/244/workbencheshttps://steelsentry.com/workbench-furniture/rd-workstation/https://www.uline.com/Cls_41/Packing-Tables-and-Workbencheshttps://www.uline.com/BL_3853/Industrial-Packing-Tableshttps://www.uline.com/Grp_537/Steel-Workbencheshttps://www.uline.com/Product/Detail/H-7698/Steel-Workbenches/Steel-Assembly-Table-Standard-72-x-48https://www.fishersci.com/us/en/products/J461FINW/laboratory-benches-tables.htmlhttps://www.nationwideindustrialsupply.com/workbench/https://www.nationwideindustrialsupply.com/departments/tables-work/tri-boro-work-master-work-benches/https://www.nationwideindustrialsupply.com/departments/work-benches-ergonomic/channel-leg-work-bench/https://www.grainger.com/category/material-handling/workbenches-and-accessories/pre-configured-workbenches-and-worktables/fixed-height-workbencheshttps://www.grainger.com/product/GRAINGER-APPROVED-Workbench-7D180https://www.grainger.com/product/GRAINGER-APPROVED-Workbench-7DG17Shelving:https://www.tennsco.com/Category/shelvinghttps://www.tennsco.com/ProductsBySubCategory/bulk-rack-shelving

author: TiN
author_rank: Super Contributor
timestamp: February 06, 2020, 11:29:23 pm
content: None of the standard benches support depth of calibrator and another 19" instrument in front of it + space for cables, accessory etc.And aluminum profile with hardware will be arriving next week anyway. Yes, it's not cost effective at all, but it wasn't supposed to be.

author: ramon
author_rank: Regular Contributor
timestamp: February 07, 2020, 04:01:00 pm
content: Oops, then too late ...But they are available. 1.2m (48") deep workbench is available on those links above (model H-7698, 72"x48", adjustable height 28-48", and 2000 lbs capacity for $450). Nothing stops you to extend the depth to 1.5m if you put a custom board over it in the same way you have planed your bench (to still have available those semicircle cuts).You can also check the sagulator (https://www.woodbin.com/calcs/sagulator/) if you haven't done yet, to check yourself why I suggested time ago plywood instead of MDF (and you can still cover it with any material you like, plywood with laminate should be a very easy material to source.).The 'semicircle cut' idea could have been expanded further and converted into a U-shaped working area in the following way:Area #1 : Workstation; R+D; and Rework. Three sections into one U-shaped (working) area, plusArea #2 : a separate (mechanically independent) calibration/long-term-testing area. (if not a separate room, or EMI closed rack ! Yes, I know you dislike racks as much as banana jacks, but they have it's reasons to exist)Your drawing shows a depth of 1.2m + space for chair, so I suppose that you have enough space to make a U-Shape possible. Otherwise you expend your time walking along your room. A U-shape doesn't mean that all three working sections need to be joined close to each other. They need to be close, but not too close. Also I don't mean that they need to be mechanically connected in single beautiful rectangular frame (in fact, you'd better have them not connected). And that is what I wanted to point out ...Cost/time effective or not is secondary issue. Main concern is that you don't need a single 1.2m or 1.5m deep bench. In my opinion that not only is not needed, it is not desirable.Having a calibrator or any other big instrument on a shelve on the wall, and one or several separate workbenchs in front (with a small gap between them) could be better. This way you don't transmit any mechanical vibration to the calibrator (or any other sensitive instrument). And if front bench has wheels, you can handle better how you access that heavy stuff at the end. There are workbenches with lockable casters that can move freely when you want and stay fixed on one place wherever you need. Yes, you said those boatanchors will be there permanently, except when you need to get them back and then once every 2 years you will get annoyed by this (and I hope that to be your only issue, take care when handling heavy stuff).Many times I found myself needing extra items or instruments around and then I add movable shelves/racks/whatever to the sides to have all items nearby at 'elbow' distance (something that somebody pointed out before). That is nontrivial If I want to be time efficient, and that is usually most of the times.Enough said, I hope you enjoy your dreamed bench for a lot of years.Please don't take this as a negative comment. I hope it could help you, in case you need a new bench 10 years after this one.The pegboard panel that was suggested is a good idea too for cables and common accesories. Much more if there are 'sliding pegboards' (check that on google images, or here ->https://www.fixturescloseup.com/2019/11/21/high-density-sliding-pegboard-display-details/). Rotary shelves are nice too for small items, but expensive.Are all the aluminum rails already cut to size or will they deliver in bulk and you need to cut them?

author: richnormand
author_rank: Unknown
timestamp: February 07, 2020, 08:38:35 pm
content: Another thing I have found most useful over the years with deep shelves (assuming available space permits it) is to have rear access to all the bench length.This allows you easy access to rear cabling of the instruments (in particular when instruments are stacked on top of each others and you need access to the rear panel of the bottom one) and some out-of-sight storage space.Particularly for the posted designs where the bench is fairly long and against the wall.

author: TiN
author_rank: Super Contributor
timestamp: February 08, 2020, 01:03:38 am
content: ramonI didn't order plywood/MDF yet however. Thick plywood in large sheets is not very common, so would be pricey for that as well. Will need about 500 sq.ft. of it.One other point most of usual benches/tables miss = adjustable height for shelves/tabletop. Design with T-slots allows that, and allows adding shelves fixtures without moving anything else. Sure, this flexibility comes at cost, but I missed this a lot.I've used this concept, but with 19" 42U rack with oscilloscopes/PSUs/etc and movable table in front of it for DUT. Didn't like it at all... More than once I connected all probes/wires between rack mounted gear and DUT PCB... then somebody knocked on table - it moved few centimeters, and hello.. wires and connections to PCB ripped clean off, changing development project into repair projectSo I don't want anything moving on the bench.Don't mind little moving around, it's good to have exercise at the lab, instead of sitting idle for hoursI've thought to make non-connected benches. Still have this ability with extrusion, just unscrew few bolts, add two beams and have two dual-section benches, eh?Current layout does not allow for U-shaped stuff.All aluminum hardware ordered precut to length, so hopefully it would be all plug and play. Delivery is about $250 for all this (~150kg of stuff).Pegboards, power delivery routing, lighting, tools fixtures will be niceties to work on after main structure is built. Need to experiment with few layouts first to see what works, and what doesn't.

author: chickenHeadKnob
author_rank: Super Contributor
timestamp: February 08, 2020, 03:32:20 am
content: Quote from: richnormand on February 07, 2020, 08:38:35 pmThis ^^^^!, if you can at all arrange it. It is pure joy to work in environments where the benches and racks are at 90 degrees to the wall instead of against it. I have done both and there is an obvious winner.

author: TiN
author_rank: Super Contributor
timestamp: February 18, 2020, 04:04:55 am
content: Today is the day. Got 230kg of aluminum goodness. It's more heavy-duty than I expected. All main bench beams will be supported by dual angles, with four M8 bolts each.Assembled one section to get feel of the dimensions/sizing. It feels super-strong even in such most unstable configuration, without sides to support. Once I have all sections interconnected, it will be like a tank. Each beam is about 4.5kg. Need to buy some hardware and M12 bolts for feet and such.Depth is perfect. With boat anchor gear like calibrators, linear power supplies, Tektronix scope/analyzer I have good amount of working area space and still can reach controls/knobs of the instruments.Next step, order working surfaces out of plywood. Will be not cheap either, as standard 4x8' sheet are not going to fit my sizing.

author: beanflying
author_rank: Super Contributor
timestamp: February 18, 2020, 04:13:38 am
content: Mmmm Shiny in a matt sort of wayMake sure you are a bit careful with the ply you choose more laminates in the board is generally better and you also preferably want an A or B face grade on one side at least so look for AB would be sensible price to look for. A for up and B for down. When you get lower in grades into C's and D's there may be holes in the faces or the face may even be bogged with filler.

author: TiN
author_rank: Super Contributor
timestamp: February 22, 2020, 06:45:02 am
content: Got some proper M12 bolts and screwdrivers for assembly.Got one more section added.Just to illustrate the area available put some pressed wood panels. 24" monitor looks tiny on the bench.This black ESD mat is 2 x 4 ft size.Will be moving equipment away tomorrow and finishing the complete frame.View under for stiffener beam. I have few extra extrusion beams, so I can reinforce one or two sections where I plan to put lot of heavy gear.Next step is fine-tuning plywood desk drawings and ordering that to custom cut from 5x10' panels.

author: Shock
author_rank: Super Contributor
timestamp: February 22, 2020, 08:43:54 am
content: Looks good, time to put the feet on. What vertically holds the weight of each shelf aside from the combined angle bracket clamp tension? Does it bite into the uprights at all?

author: TiN
author_rank: Super Contributor
timestamp: February 22, 2020, 09:00:59 am
content: Uprights?The frame design shown on first post 3D card image.It will be very close to that after assembly. Bottom short beams (at leg level) most likely will not be installed, after assembly I feel those are not necessary.I tried to load middle of the single long beam on section 1 with 110kg today and barely detected <6 mm deflection. In actual use there will be much better load distribution always between 5 beams and plywood.

author: Shock
author_rank: Super Contributor
timestamp: February 22, 2020, 10:28:18 am
content: A length mounted vertically is called an upright.

author: TiN
author_rank: Super Contributor
timestamp: February 23, 2020, 02:59:21 am
content: Alright, it's shaping up into something now. I'm done today with 3 sections, one more to go tomorrow. Put some shipping pallet on section 2 to pile some gear and get a feel of layout.Reach to scope by the left and to top gear is little too far, but nothing stops me from moving that gear 10-15 closer to the front. Otherwise distance is perfect, and I still have plenty of space in front half to work on full-size equipment.I've put additional 2m beam on section 3 and loaded it up with ~200kg of calibration equipment.Measured bend in the middle of the extruded beam is ~9mm. Once I get plywood on surface, it will be even less due to spreaded load across larger area.Remaining section to build will be located by the right of the calibration gear. Long term experiments will be hosted on that part, with thermal chamber, datalogging stuff and auxilary hardware for that. Perhaps my primary voltage, resistance and current standards will be moved there too, onto top shelf.Overall, I am happy how this shaping up, and 1.5m bench depth is just right. No siglols or riglols in my lab, so everything need proper depth to allow decent working area in front.

author: Shock
author_rank: Super Contributor
timestamp: February 23, 2020, 07:18:25 am
content: When you are done you can take a bottle of champagne and smash it across her bow.

author: wizard69
author_rank: Super Contributor
timestamp: February 25, 2020, 03:57:54 am
content: Quote from: TiN on January 12, 2020, 06:27:53 pmI'd read up on ergonomics. The front vertical posts are going to be a massive pain in the butt. You wll end up having to work around them, look around them and generally cus at them for being in the way.The depth of the bench is a variable and depends greatly upon what sort of work you will be doing. Too much depth though wastes space, is uncomfortable. I don't think anybody can say for certain what is the ideal depth due to al of these variables.In general I would rather see adjustable instrument shelves.Aluminum is a very good conductor and as such can be dangerous. At the very least ground the frame. However most extrusions are anodized so actual conductivity is unknown. It might be better to do wood but apparently you have already considered that. By the way particle board does mover over time, it should be well supported.Wheels! think about wheels to move the heavy stuff around, you will thank yourself as you get older. I would rather see part of your bench become modules that you can roll about. This starts to become non trivial as you mechanical design goes through the roof.Finally steel is bloody cheap compared ot aluminum.

author: Shock
author_rank: Super Contributor
timestamp: February 25, 2020, 02:15:46 pm
content: Quote from: wizard69 on February 25, 2020, 03:57:54 amWhen designing mine I faced similar problems. There is no easy way to combine deep shelves and deep benches and it be ergonomic.So I went with three sets of 2400mm industrial longspan bays of 600mm deep shelving and set them up so they sit over my benches. When I push my benches fully in there is only a small amount protruding. I can then easily access the rear of equipment to change cables and move things around. It's also easier to get to the top and bottom shelves which I use for storage.It's a weird way of doing it but works surprisingly well.

author: TiN
author_rank: Super Contributor
timestamp: July 20, 2020, 12:39:58 am
content: Finally got the plywood delivered and installed in the bench. It's shaping up nicely. I am very happy with depth.Sadly had to abandon idea with non-standard plywood sheets, so no more belly cutouts and extended overhangs.Current table sheets cut from standard 2.44 x 1.22m size just barely make it depth-wise, but it will do for 2020 until covid situation improves.Still have lots of work left for refining power routing, lightning and storage areas, but that's fun part and I can resume working on long overdue projects with current setup.Photos of today's state:Section 1 - RF and auxilary gear, storage for tools and long-time projects.Section 2 - main working area, rework equipment, fume extractor, scope, logic analyzer, power supplies, SMUs, microscope.Section 3 - reference DMMs, calibrators, AC measurement equipmentEquipment layout. Bench have enough room to put full-size full-depth 19" equipment in front of lab gear, which was primary goal for bench depth choice.Section 4 - calibration standards, temperature chamber box, AC standards. xDevs server on top 3rd shelf.Storage IKEA boxes for connectors, parts, etc.Various tools hanging off vertical beamsUnderside supports for benches. Can see IP-controlled power switch.

author: Shock
author_rank: Super Contributor
timestamp: July 20, 2020, 12:00:39 pm
content: I admire the work you have put into it, it's a beast for sure.Whats your thoughts on the front uprights now that you look at them? I'd be tempted to move them half way back to ~600mm deep and put bench height legs in the front. It also would make the room feel a bit more open and the bench look less chaotic.You can still have ~600mm deep shelving if required which should be plenty deep enough if you want the top shelf to have overhanging lighting and still let in good lighting from the ceiling. As a bonus you would also gain the further possibility of a ~600mm deep recessed shelf under the bench for concealed storage.5 of the old shelf supports become the new legs and if you get the ~600mm depth right the off-cuts from those can be re-purposed to give more shelves.

author: bjbb
author_rank: Contributor
timestamp: July 20, 2020, 09:40:01 pm
content: Get rid of the carpet. Not good for most electrical/electronic work places.

author: rhb
author_rank: Super Contributor
timestamp: July 20, 2020, 10:42:57 pm
content: Nice looking bench. I'm using rectangular steel tubing for mine because Dad left it to me. My major question is weld vs bolt. I was going to weld, but if I bolt it's a lot easier to change.In my case I'm building two benches on casters with ESD flooring on the tops. One bench will be racks for the HP gear and the other will be shelves for the Tek and other non-full rack width gear. I'm putting down ESD flooring, so the bench tops will be made from the scarp from the flooring. Unfortunately, the flooring is not cheap.For anyone wanting to do something like TiN's design but not wanting to spring for the aluminum extrusions, this should be a lower cost option:https://allmetalsinc.com/steel-perforated-tubing.htmlIt should be available worldwide. It's commonly used for street signs which is the application I saw a few days ago leading me to think I should have a few pieces on hand in my steel stock pile.Have Fun!Reg

author: Renate
author_rank: Super Contributor
timestamp: July 20, 2020, 11:17:47 pm
content: Fortunately I'm in the minor leagues, I make do with 1" square aluminum tubing.I buy the stuff with a 1/4" slot to slide in panels which divide the foot space from storage and add structural integrity.https://www.mcmaster.com/structural-framing/structural-framing/press-fit-framing-and-fittings/I'm actually very, very glad that I don't have that much stuff.

author: ramon
author_rank: Regular Contributor
timestamp: July 22, 2020, 10:18:45 am
content: Congratulations. Seems that it have fit your purpose goal.I found missing the 43" monitor. Where is it?Wait ... don't tell me you are going to buy a 86" monitor?

author: Shock
author_rank: Super Contributor
timestamp: July 22, 2020, 11:17:03 am
content: Quote from: Renate on July 20, 2020, 11:17:47 pmGood way to get into hobby repair is own enough things till they break.

author: TiN
author_rank: Super Contributor
timestamp: September 24, 2021, 12:33:19 am
content: In case someone missed, Dave featured this bench build in 1420 Mailbag episode:.

author: Shock
author_rank: Super Contributor
timestamp: September 24, 2021, 05:15:42 am
content: Tin yours is the best precision bench I've seen. Shahriar probably has the best RF bench. Dave the best scope bench.I have the strongest bench shelves! Heh, I don't do too badly picoamps, microohms and microvolts is all I need. I do have a gpsdo though for a reference standard so not in total ppm denial.

author: NukeET
author_rank: Contributor
timestamp: September 24, 2021, 05:46:37 am
content: For what it’s worth, aside from potential rigidity issues, I really like the layout. I’d say your best bet would be to just find an electronics bench or lab bench second hand. They are surprisingly common and not usually very expensive. I managed to find one that had an electric lift and everything for like 160 dollars (a steal considering it was over 3000 dollars new) That would be far cheaper and a lot more robust than a constructed one. There are deals to be had on Facebook marketplace. It pays to check it daily.

author: Shock
author_rank: Super Contributor
timestamp: September 24, 2021, 06:31:49 am
content: Depends were you live, they are really uncommon here. The ecosystem created from areas like the valley create a huge supply there. In Australia it's old printers and dead chinese TVs.

author: NukeET
author_rank: Contributor
timestamp: September 24, 2021, 07:22:05 pm
content: I have been undoubtedly blessed by a wealth of marketplace junk. Amazing what people throw away here.