Where to get EMC/EMI Metalic PCB Shield? - Page 1
Forum section: electronics / beginners

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 07, 2019, 01:09:13 am
content: as the topic states... i'm talking about very small shield like 25 x 10 x 5 mm dimension that i can put a pcb inside, anybody who own (or dismantle) Tek active probe P6245 et al will know this. apart from the normal larger shield that is soldered or clipped on to the pcb. anyone know good suppliers? i found hollandshielding.com but few reasons that i hate:1) they only show larger shield2) no clear price tag for estimation of my product3) we need to send email and the file and wait for their reply with quotation4) i'm not sure if they can work internationally to remote place like here.

author: Jwillis
author_rank: Super Contributor
timestamp: January 07, 2019, 01:22:01 am
content: EMC/EMI shields are just grounded metal covering the sensitive component .So really any metallic project box fitting those dimensions would work as long as it's grounded.

author: chris_leyson
author_rank: Super Contributor
timestamp: January 07, 2019, 01:51:50 am
content: Wurth or Harwin might do something close.

author: radar_macgyver
author_rank: Frequent Contributor
timestamp: January 07, 2019, 05:15:44 am
content: What kind of volumes? For one-offs, it might be easier to get a shielding case milled out and screw it to the PCB, or try to use a standard size one like from Laird, Leader Tech, etc; seehttps://www.digikey.com/products/en/rf-if-and-rfid/rf-shields/867(14R-CBSA-0.5X1.0X0.13looks close). For larger runs, shops likeFotofabcan build to order.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 07, 2019, 11:47:10 am
content: Quote from: Jwillis on January 07, 2019, 01:22:01 amyup except the aluminium/metallic enclosures that i have in stock measures something like 150 x 150 x 50 mm, i need something small like the above mentioned 25 x 10 x 5 mm, it should looks like a perfect box, wait i got the picture (attached), something like that, inside the shield (pushed in not soldered) is a pcb/hybrid for Tek P6245 probe, currently i'm making pcb circuit of that about same dimension (a bit bigger actually) and requires about the same method of shielding. it looks like a hollow square bar. if i know a long steel hollow bar of that size (i measured 6 x 3 mm, 30 mm long on the Tek probe) sold anywhere, i will be happily buy it and cut to pieces, if price is reasonable. for one-off or personal use, maybe i can cut aluminium can and bend to shape, or just use food aluminium wrap foil, but i need to know where to get something neater and more professional look.Quote from: radar_macgyver on January 07, 2019, 05:15:44 amnot many for first few prototypes, but its good to know supplier for massive quantity. the digikey list doesnt show what i'm looking for but maybe usefull in the future, thanks.

author: Wendy_Preston
author_rank: Contributor
timestamp: January 09, 2019, 04:35:04 pm
content: Hi Mechatrommer, apologies for the delay in replying. Perhaps our Shield Can development kit might be something you could use? It has 2 scored sheets of metal (scored at 5mm intervals), which you might be able to cut into the shape you need?https://www.harwin.com/products/S01-806005KIT/If you click on the availability button on this page, you can see which authorised distributors have stock, and click through to their sites for pricing. Feel free to contact me on technical@harwin.com if I can be of further assistance.

author: langwadt
author_rank: Super Contributor
timestamp: January 09, 2019, 04:59:22 pm
content: close enough ?https://www.ebay.com/itm/183103607580

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 10, 2019, 01:04:34 pm
content: Quote from: Wendy_Preston on January 09, 2019, 04:35:04 pmthis is interesting. something we can shape to our own need this has many applications in (esp hobby) electronic/rf projects. digikey shows $25 price per unit, is that for 2 pieces and 2 trays of clips as pictured? or just a single plate single single tray (12 clips)? i wish there are ebay suppliers for this kind of thing...https://www.digikey.com/products/en?lang=en&site=us&vendor=0&WT.z_cid=sp_952_buynow&mpart=S01-806005KITQuote from: langwadt on January 09, 2019, 04:59:22 pmyes close enough thanks, i can try to make pcb to fit in those. here our ebay malaysia link...https://www.ebay.com.my/itm/2pc-Copper-Rectangular-square-Tube-pipe-10mm-x-8mm-x-1-5mm-Wall-x500mm-long-V-b/183103608101?hash=item2aa1d35525:g:44MAAOSwN5VamMlB:rk:1:pf:0EDIT: (Ebay keyword: Copper Rectangular square Tube pipe)earlier i tried to find "hollow" square and rectangulare bar in ebay, i only find one supplier from USA, i think its cheaper per unit volume than the china link you provided (6 bars in a pack, 3 foot long (90cm) each) even including shipping cost...https://www.ebay.com.my/itm/Brass-C260-Hollow-Rectangular-Bar-ASTM-135-5-32-x-5-16-0-014-Wall-36/223306721723?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649edit: i just wonder why newer posts didnt show up in my "unread thread" page there's some bug in open machine forum i think

author: coppercone2
author_rank: Super Contributor
timestamp: January 10, 2019, 01:06:09 pm
content: hollandshielding is bullshit, they want your SSN for fucking small orderswhacked out paranoid but nice documentation on their website. The samples are of nice quality though, if you want to give them SSN later for the order!Their quote people are not too bad to deal with but still, who asks for SSN. I thought I was doing business with DPRK.Keep in mind you can make a really professional custom box by yourself, if you use solder or silver solder, careful layout/measurement, cutting, bending on flat jigs if you bend.Keep in mind if you make a solder joint, you can use a file to make it smooth, sand it and polish it. If you braze like 95% of the strength is in the lap joint, so there are basically no penalties for filing/sanding the bevel flat. Then you can use different grits of paper and a polishing wheel with rogue to get it to a mirror finish if you want. Look at haris brand low temperature solder (different kinds for metal and aluminum) (I have used metal solder @ 450F with a hand soldering iron to do a steel box of significant gauge) and brazing if you have a torch (you won't do this with a iron), for a small box you can do it with one of those 1 liter oxy/mapp gas torches you can buy for 50$.The key is to use strait edges and a sharp scribe while you mark and to cut carefully with a variety of good sheers. With a bit of work your home made thing can look better then the picture of the thing in your hand. ***The biggest misconception about brazing/soldering is that people think its like welding. You get basically no strength from the fillet. You don't need a fillet. You can remove the fillet* The fillet is ductile and weak compared to the lap joint. *** If you just have a fillet with no penetration you did it wrong and its weak (common problem with 'tig brazing' videos on youtube). For instance, the way they used to do tank barrel nesting, is to get the ENTIRE barrel heated to red with like 5 guys with torches, then add pure silver to one end until it shows up on the other end. It should put things into prospective.For instance if you want a mirror finish on aluminum just get a orbital sander, go from 220-330(if you got it)-400-800-1000-1500-2000-polishing compound. If you get the velcro-type disks that attach to the sander, and you put the sander in a vice, you can do a small part to mirror in around 30 minutes or less. Autoparts has all you need. Should work fine for copper and stainless too. Look at youtube for 'mirror polishing aluminum' and mirror polishing stainless steel to see what you can get, I saved quite a bit of money on old outdoor furniture that I thought was completely fucked.youtube.com/watch?v=GTJmlXSCD0Ayoutube.com/watch?v=8Bu2fDKLUp0 (do this to make a sander you can use small parts on, just clamp it in a vise (but obviously use a orbital one). Hold the parts carefully in leather gloves. It will be lighting quick for that little thing you want to make.

author: cdev
author_rank: Super Contributor
timestamp: January 10, 2019, 11:36:20 pm
content: copper tape can be really useful in improving the shielding of commercial boxes which are rarely the exact same size as a PCB. Another purchase that I've found really good to have around are these SMA end launch connectors that also are threaded and have a nut and are extra long. So, then you can solder the SMA to the end of the PCB, plus feed the SMA out of the side and use its nut with the lockwashers on it, to make good connection to a metal case, not just one or the other.Also you can use copper tape inside a box to improve the shielding internally.Sometimes you may also want quick and dirty shielding - copper tape is great for that.Before I had copper tape I used flashing copper.Thick copper sheet. It's highly conductive, takes solder extremely well and makes excellent shielding for RF but its much more expensive than copper tape and it has to be soldered in place. (which also gives you a better connection than adhesive alone with copper tape. Copper tape shields better if its both stuck on and soldered appropriately.)The ways that professionals shield PCB sections vary but one thing I often see is the use of thin sheets of tin, often with holes cit in it for ventilation. Tin is of course easily solderable, and much stiffer than copper. Its easy to make small boxes out of tin.Copper flashing is so soft and flexible it is not well suited for anything that requires mechanical strength.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 11, 2019, 04:28:47 am
content: i also consider the food tin foil, but cant find one yet in the kitchen, got to ask swmbo or i have to buy one for testing...can it work?

author: Kasper
author_rank: Frequent Contributor
timestamp: January 11, 2019, 06:45:12 am
content: http://www.ksmetals.comHas a good variety. Their brass strips worked great for me but they also have round and square tubing.Your local hobby store might carry it.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 11, 2019, 07:12:06 am
content: My local hobby store only carry wires for home electrical, fans/motors condenser and transistors replacement for car audio... you start asking something you design yourself, you out of luck, not even a uA741 nor a zener..

author: Wendy_Preston
author_rank: Contributor
timestamp: January 11, 2019, 08:39:08 am
content: Quote from: Mechatrommer on January 10, 2019, 01:04:34 pmOne pack includes 2 sheets and 2 strips of clips (24 clips), as pictured. The isntruction sheet ishere.

author: coppercone2
author_rank: Super Contributor
timestamp: January 11, 2019, 12:41:12 pm
content: I think your system would be better if you provided the clips in a long strip that can be spaced closer together to make the slot antennas smaller, so they can be cut like SIP headers to a correct length. And bent into a square or whatever shape you want.Or at least have an option for it, 4 points of ground contact for a shield might not be enough.If you do make your own, be sure to get oxygen-free copper sheet for best performance, or nickle-silver for lower frequency performance (as HARWIN uses).

author: Eka
author_rank: Regular Contributor
timestamp: January 13, 2019, 01:27:49 am
content: Any technique they use for metal jewelry box making can be used to make custom metal boxes. A forming anvil could be as crude as a piece of tool steel bar stock cut off square and held in a vice. Dremels with cutoff wheels are great for cutting the shapes for tabs, etc into a sheet of very thin metal. A small precision vice can be used to clamp a piece of metal as one hammers over a small tab. Often with very thin metals, they can be formed with just hand pressure instead of hammering. I've used various rods and bars to pinpoint the pressure. For thicker metals various rods and bars can precisely direct the energy from a hammer blow.

author: coppercone2
author_rank: Super Contributor
timestamp: January 13, 2019, 06:15:14 pm
content: i used my teeth to form the tip of my copper bicones lol

author: Andreas
author_rank: Super Contributor
timestamp: January 13, 2019, 06:45:28 pm
content: Hello,nearly every PCB manufacturer (at least here in germany) can etch yourhousings from either brass or nickel silver sheets (0.1 - 0.3 mm thick)I etched some parts at home with one of those photosensitive brass sheets:https://www.conrad.de/de/messing-blech-fotobeschichtet-negativ-messing-l-x-b-x-h-215-x-145-x-03-mm-bungard-271003145-inhalt-1-st-529060.htmlOn the picture: a housing, a coin cell holder, a holder for a o-ring gasket, and a spring which connects the housing to the front pcb.with best regardsAndreas

author: Kasper
author_rank: Frequent Contributor
timestamp: January 13, 2019, 06:55:08 pm
content: Quote from: Andreas on January 13, 2019, 06:45:28 pmI like it! Thanks for sharing.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 13, 2019, 07:20:51 pm
content: i tried food aluminium foil isolated with wrapping plastic, i can say its 90% effective, but not neat.

author: Wendy_Preston
author_rank: Contributor
timestamp: January 18, 2019, 12:04:25 pm
content: Quote from: coppercone2 on January 11, 2019, 12:41:12 pmIt's certainly a valid idea. However the type of market we aimed the shield clip for are doing high volume, automated pick and place for the PCB. This system allows for the clips to be placed from conventional tape within their system. The development kit was a later addition to the range, to assist PCB engineers in the development stages of their projects and get the clip system designed on their PCBs. Hence why the development kit uses the most popular design of clip that we sell in volume.Definitely not the only way of doing it, just the one that worked for our market intention.

author: max_torque
author_rank: Super Contributor
timestamp: January 18, 2019, 07:11:53 pm
content: For proto's i just buy a sheet of thin (0.3mm) brass (easily available at hobby/modelling shops and online) and use a pair of tin snips (like big scissors) to cut it out, and just bend it over any straight edge. Solder it together and bingo, you're done!The Harwin surface mount retention clips are really useful too, especially during EMC development where they allow us to carry out back to back EMC tests with and without various shields in place!

author: Mechatrommer
author_rank: Super Contributor
timestamp: February 04, 2019, 06:34:42 am
content: Quote from: Mechatrommer on January 10, 2019, 01:04:34 pmi received the item yay, exactly the size i'm expecting. but sadly the listing of the item is no more, i'm the last mohican ordering it i guess, iirc it was indicated that they still have few stocks of it, but now no more, sad. even the listing is changed to some type of fountain pen they claimed their system got FU i almost panicked when it happened i aint order a pen. well, with what i got i can still make 100+ of circuits, the cost for each cut unit (BOM) will be about 20 cents each not that bad. if for some magical reason i need more i have to move on to china source or harwin type of folded shield. fwiw...

author: noname4me
author_rank: Regular Contributor
timestamp: February 05, 2019, 06:40:13 pm
content: Quote from: Mechatrommer on January 11, 2019, 04:28:47 amTry aluminium roofing tape inside the box.Make sure the adhesive is conductive as well...most are...I dont think I've found a roll yet that wasn't.This has been used in production and R&D successfullyThis is better than food foil because the tape sticks to the inside of the box, so you dont get a mess of foil when it all comes away from the edges