Case production - Page 1
Forum section: electronics / beginners

author: jimon
author_rank: Regular Contributor
timestamp: June 11, 2015, 10:31:59 pm
content: It's quite easy to get idea how to make commercial grade electronics (thanks to YouTube it's even much much easier). But it's not that trivial with casing.Let's say a goal is to produce something like this :http://www.muji.eu/pages/online.asp?Sec=8&Sub=29&PID=7040It's a quite simple device (but not the simplest ever).I can guess that for rough case prototypes people are using 3d printing nowadays.But then what ? For printing people are often using pantone palette, I found their plastic palettehttp://www.pantone.com/pantone-plastic-standard-chips,ok, we can get idea what final color will be.What about texture ? Do we have go-to standard texture palette ?What about moldings ? From kickstarter I've seen that "tooling making" is quite big part of preproduction cycle. What exactly they are doing there ?I guess after molds are done, we can actually produce plastic parts. But what about final assembly ? How it's done ?How it's done when case have metal parts ? For exampleDas Keyboard 4have an aluminium top, how they probably make it ?What about resin buttons ? Do they also go though same production process (molding) as plastic buttons ?Labels on plastic ? I know that for computer keyboard buttons people are often go with double injection moldingAnd are there any go-to companies in EU who handle\help with casing and assembly for small production runs ?

author: hayatepilot
author_rank: Frequent Contributor
timestamp: June 12, 2015, 09:44:58 am
content: Case design and manufacturing is normaly done by mechanical/manufacturing engineers. You can spend your whole life in this field and still know hardly anything.But I try to answer your questions.QuoteThe manufacturer has to design and machine the injection moulding tools. This is very expensive, expect in the tousands of € per tool. Of course you can make multiple different (simple) parts with one tool. And the tool last normally many thousand (up to 1 million) shots.QuoteDepends on the quantity and complexity of the product. Most will be assembled by hand.QuoteMetal parts also have to be machined. There are many many different types of manufacturing: drilling, turning, milling, punching, bending ect...QuoteResin is a plastic so yes.They could also be casted, whitch requires much cheaper moulds.QuoteMost labels are printedAnd are there any go-to companies in EU who handle\help with casing and assembly for small production runs ?I found with a quick search this company for prototypes and small run manufacturing:http://cp-gmbh.de/en/There are probably hundreds of companys like this in europe.I hope I could answer your questions.Greetings

author: jimon
author_rank: Regular Contributor
timestamp: June 12, 2015, 06:07:14 pm
content: hayatepilot, thanks for answers. If I want to create a casing for a product, which tools and steps you can recommend ? I can easily design prototype with 3d printing, but then what I should do ?

author: IconicPCB
author_rank: Super Contributor
timestamp: June 13, 2015, 02:34:29 am
content: 3D print the case?

author: jimon
author_rank: Regular Contributor
timestamp: June 13, 2015, 09:22:09 am
content: Quote from: IconicPCB on June 13, 2015, 02:34:29 amI can 3d print 1-5 cases, but not 100, and 3d printing texture quality is not the best.

author: lapm
author_rank: Frequent Contributor
timestamp: June 13, 2015, 09:23:11 am
content: Quote from: IconicPCB on June 13, 2015, 02:34:29 am3D printing is nice if your making one of prototype or just couple of them... But when you talk tens to thousands and even bigger scales, 3D printing is no longer cost or time effective...

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: June 13, 2015, 09:26:19 am
content: The normal first step is to find an off-the-shelf case and have it machined and printed. Most case manufacturers offer customisation.

author: hayatepilot
author_rank: Frequent Contributor
timestamp: June 14, 2015, 03:29:27 pm
content: Quote from: jimon on June 12, 2015, 06:07:14 pmIt depends entirely ond the complexity of the product and how professional looking you want it. And of course the quantity.I would contact a prototype or small volume manufacturer (like the one linked above) and discuss with him what you want to do. They can usually make you an offer if they have drafts of the parts and/or CAD files. These quotes usually don't cost you anything.I'm shure there are such companies in sweden too. Google is your friend.Or do as mike above said and try to find an existing case you can modify. This is the easiest and usually cheapest method.Greetings

author: codeboy2k
author_rank: Super Contributor
timestamp: June 15, 2015, 08:56:56 am
content: Quote from: mikeselectricstuff on June 13, 2015, 09:26:19 amThis is what I would do, even if I was Kickstarting something. So many Kickstarter projects have died spending all their money on tooling and machining costs back and forth with a manufacturer. It's far less risky to try to make it work with pre-built cases and then you only have more reasonable machining and printing costs to deal with, which can be kept under control.

author: jimon
author_rank: Regular Contributor
timestamp: June 15, 2015, 12:51:14 pm
content: But how exactly hard tooling is ? We have local makerstore here, they have CNC machine, so practically it should be not that hard (except to figure out where to get block of steel). Still I have no idea about texture patterns on plastic. But at least for color I can use pantone ...Looks like for simple stuff people are using silicone molds, wonder if results are any good, but you cannot (or can?) CNC siliconeso one needs an original to make a mold .. and to make an original one needs a mold ..

author: JoeN
author_rank: Frequent Contributor
timestamp: June 15, 2015, 06:08:25 pm
content: Quote from: jimon on June 13, 2015, 09:22:09 amI suspect if you are looking at quantities in the hundreds you are stuck with using standard industry cases. It's just not a big enough job for a custom case unless you can justify a case that costs many hundreds of dollars. It isn't sexy, but low volume products end up like these guys:http://www.ebay.com/itm/RF-Signal-Generator-35MHz-to-4-4GHz-via-USB-17dBm-and-Features-PulseTX-/201369037569http://www.ebay.com/itm/10-VOLT-DC-Precision-Voltage-Reference-Standard-Nulled-to-Fluke-732A-or-732B-/261499015291For a semi-custom case I have seen some products done up like this, custom cut acrylic sheeting, assemble the cuts into a case:http://www.ebay.com/itm/SALE-Ice-Tube-Clock-Fully-Assembled-IV-18-VFD-retro-display-/171781150988http://www.ebay.com/itm/AD584-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Module-/181235948445Maybe that is something to consider.Have you considered Dave's method of building out a generic case to give it some uniqueness?http://www.eevblog.com/projects/ucurrent/Dave's probably sold these in the low 1000s and it's still too small of a run for a custom case.

author: free_electron
author_rank: Super Contributor
timestamp: June 15, 2015, 06:47:13 pm
content: for beuatiful enclosures :box enclosuresrose-boplahammondveromboxtakachiokwdeltroncamdenboss

author: JoeN
author_rank: Frequent Contributor
timestamp: June 15, 2015, 06:51:40 pm
content: That's a good list. Let me add one:Bud Industries -http://www.budind.com

author: wraper
author_rank: Unknown
timestamp: June 15, 2015, 06:59:53 pm
content: Quote from: jimon on June 15, 2015, 12:51:14 pmI really doubt their CNC machine is able to work on steel. This is not the realm of cheap CNC machines made of aluminium. To work on steel, very sturdy construction is needed.

author: codeboy2k
author_rank: Super Contributor
timestamp: June 15, 2015, 07:06:12 pm
content: Also see the EEVblog Wiki on enclosures. There's more there.http://www.eevblog.com/wiki/index.php?title=Enclosure_ManufacturersI added Deltron and CamdenBoss from FreeElectron's list. All the others were already there, including Bud Industries from JoeN

author: LabSpokane
author_rank: Super Contributor
timestamp: June 15, 2015, 07:26:04 pm
content: The likelihood of successfully machining your own injection mold knowing nothing about tooling or injection molding is zero. Actually that's wrong. The likelihood must be expressed as a complex number. Let me fire up Matlab and get back to you on that.

author: JoeN
author_rank: Frequent Contributor
timestamp: June 15, 2015, 07:38:36 pm
content: Quote from: LabSpokane on June 15, 2015, 07:26:04 pmI'd use a Finite Improbability Drive to derive that number.

author: rx8pilot
author_rank: Super Contributor
timestamp: June 15, 2015, 07:48:04 pm
content: Quote from: jimon on June 15, 2015, 12:51:14 pmA CNC machine is like a piano. If you are not skilled in the art, you will only get shit out of it.I have spent about 10 years designing and manufacturing specialized enclosures for commercial electronics. The biggest problem with 3D printing is that is allows you to break nearly every rule in the manufacturing book. If at some point you need to CNC from metal, cast, or mold the parts they have to be designed for that process. Period. End of story. The learning curve for designing something that is a step up from a project box is not trivial at all. It becomes even harder when you need to hit a cost and time target.I don't hate 3D printing, but I do get frustrated when they are used to create a prototype that cannot be manufactured any other way. There was a project I did a number a years ago that needed a very sophisticated enclosure. I did the concept in 2 days and had it printed. One of my guys (a model maker) finished it to look like a real product. Showed it to the client and they loved it. After six more months of engineering, we were able to deliver. 2 days for 3D print. 6 months for a released product.Quote from: hayatepilot on June 12, 2015, 09:44:58 amThis is true, am I learning new things every minute of every day on each new design. Especially true when intangibles like 'look' and 'feel' are in play.

author: rx8pilot
author_rank: Super Contributor
timestamp: June 15, 2015, 08:06:48 pm
content: Quote from: jimon on June 15, 2015, 12:51:14 pmDude. The learning curve for CNC machining is MASSIVE. Doing molds, even more so. A million details that all interact with each other. Absolutely no room for error.After spending 10's of thousands of hours in setting up, programming, and operating CNC's - I have the experience to tell you. The smallest mistakes will result in:A. You arm being crushed just before it is torn offB. Very expensive damage to a giant machineC. Your part or the tools are destroyed.If you can get past those things, next you need to know how the get the part you need out of that machine. That starts with knowing how to design the part based on the problem, materials, and the tools. It is not impossible to learn, just don't fool yourself into thinking it is no big deal. My first CNC was purchased when I did not even know how to turn it on. I only got it to make some 'easy' parts. It was never easy and still isn't even today. I ended up becoming a machinist instead of the designer that I wanted to be. It was a double-full-time job learning what I needed to know to make what I previously thought was simple stuff.

author: LabSpokane
author_rank: Super Contributor
timestamp: June 15, 2015, 08:12:20 pm
content: On a more serious note, if 100 cases is what you are after, you will be doing what was already suggested: buying a customized case. Don't even consider buying tooling.One can drop 50,000 Euro in the blink of an eye with "hard" tooling. Managing that tooling and tweaking into into production readiness will consume many thousands more. I was a plastics engineer early in my career. If you're *seriously* in the position to go into hard tooling, I can try to guide you a bit, but for anyone to go from zero to production molds, you're going to need professional help. Plan to spend 10's of thousands more for the engineers to make that happen.What RX8 said about the design for manufacturing (DFM) is right on the mark. There is no resemblance between what can be successfully printed or machined on a prototype basis versus what will be successfully molded, assembled, and function properly.And you usually need more than a CNC machine. Electrical discharge machining (EDM) is a key process in creating the molds. Only very crude molds are made solely by machining.========================As for colors: Plastics manufacturers offer stock colors, or you can have the material pre-colored to your spec, or you can buy "natural" resin and color it with a coloring agent.As for textures: Texture is photochemically etched into the mold using a process very similar to that used to etch PCBs. There are many to choose from and the texture houses can supply you with a book of different samples molded onto plaques.

author: Corporate666
author_rank: Unknown
timestamp: June 15, 2015, 08:35:56 pm
content: Quote from: jimon on June 15, 2015, 12:51:14 pmIn addition to the (great) advice you've been given above...An injection mold will generally cost between $5k and $20k for a relatively simple part. $5k would be having a mold made in China, and $20k would be USA or European pricing for a simple mold. By simple, I mean two pieces that open up to reveal the part inside. The part must be designed to be molded - draft angles on the walls instead of straight up-and-down faces. That detail (draft angles) is just one of hundreds of things that must be done to make a part easily molded (the knowledge rx8pilot was referring to). It is all too easy for an inexperienced person to design a part that can't be manufactured or can't be made cheaply. For example, square outside corners are no problem. Square inside corners are a problem - and to get them truly square, you need to EDM machine the corners at great expense. If a mold cannot be a simple pull-open style, then you are talking about a so-called "multi-draw" mold where there may be three or more pieces which come together to hold the part. Such molds get exponentially more expensive than a simple single draw mold. A large or complex mold could easily run $100,000 or (much) more.The CNC machine at your local makerstore is almost certainly orders of magnitude away from what is needed to cut a metal mold. Molds should be cut from special alloys of steel, and accuracy is very important. The cost of the metal to make a mold could easily be a few thousand dollars, and to get a smooth surface (like seen on a drink bottle) means the mold must be machined to within tenths of a thousandth of an inch. Machines which are powerful and accurate enough to cut mold steel accurately and quickly are extremely expensive. I say "quickly", because the way to make your mold smooth is to use very small tools, like a ball-shaped endmill 1mm in diameter... which means you "step over" perhaps 0.25mm per pass. You are taking very small cuts - which means it takes a long time, which means you need a fast machine to get it done. Even a fast machine could take 50 or 100 hours to machine a part... a slow machine could be 10 times slower.Here is a machine cutting part of a mold for a quadcopterYou can see it going over and over the mold, decreasing the step-over distance each time and increasing the resolution and surface finish. The machine doing that cutting is a few hundred thousand dollars.Here is an even more complex mold being done on a Hermle 5-axis machine. This machine is quite a bit more expensive than the Datron is - likely more in the neighborhood of a million dollars for this machine.As for patterns on the plastic - they are cut into the mold itself. There is a whole area of expertise called "patternmaking" and patternmakers are very specialized types of machinists who get paid a lot of of money. They are the ones who texture a mold to give you the various looks you are used to seeing on products (smooth, matte, glossy, dimpled, etc).

author: codeboy2k
author_rank: Super Contributor
timestamp: June 15, 2015, 10:48:59 pm
content: Quote from: LabSpokane on June 15, 2015, 08:12:20 pmI don't remember now which kickstarter project did this, but I remember that there was one project that got over 1 million dollars funded, and they spent about $900,000 on mechanical design services with a contract manufacturer and tooling fees to build prototypes.I think they spun the tooling twice or more. That project had no more money left to complete it.

author: SeanB
author_rank: Super Contributor
timestamp: June 16, 2015, 08:11:31 am
content: I deal with moulds at work, so have a very good relationship with a tool and die maker ( and a very good one at that, he is currently on holiday in Australia at the moment), so have had a few replacement dies made over the years. Started with a 20kg block of brass, and landed up with 18kg of brass shavings. Needed some shaped cuts in the mould, so no problem, he made a cutting tool for the mill out of HSS and carbide tip, ground to the right profile and used to make the cuts. Then needed a sealing plate, which had to be cross hatched and hardened to 60RC, and still be flat after hardening. His last job as light recreation was doing a 3 wheel bike conversion from push toy to petrol powered, and I could see all his work just from the smooth finish on it.

author: jimon
author_rank: Regular Contributor
timestamp: June 19, 2015, 08:41:22 am
content: Thanks for the answers everyone !So I should expect 5-20k$ for simple tooling, and up to 100k$ for complicated one's. So let's say tooling will cost 200k$, then for 100 product batch it will be 2k$ per productBut for 10000 batch it's 20$ per product, which is not that bad. Plastic is pricyWhat about aluminum cases ? Looks like it's much easier to CNC aluminum and different finishes are doable on small scale. Laser cutting aluminum ?

author: Falcon69
author_rank: Super Contributor
timestamp: June 19, 2015, 08:49:52 am
content: It will be more expensive to make from aluminum. Aluminum is even more costly and machining time. However, you need to balance and price the quantities you need. And also you need to factor in the strength of the materials (aluminum vs plastic) if strength is a factor.Lately, I priced some molds out. It was like 5grand for a simple mold, and less than $2 per part when ordered 10,000 for plastic. Molds are the way to go for any large production, unless you need the strength, then go for aluminum. But, if the product and mold are designed well, plastic can be pretty strong as well (no where near aluminum, but strong nonetheless)However, for the same part milled from aluminum, it was $75 per part when ordered in 10,000.

author: jimon
author_rank: Regular Contributor
timestamp: June 19, 2015, 08:59:36 am
content: Quote from: Falcon69 on June 19, 2015, 08:49:52 amAnd if it's 100-1000 then is it still 75-100$ per part ?

author: Falcon69
author_rank: Super Contributor
timestamp: June 19, 2015, 09:12:19 am
content: ya, the price goes up for less quantity, but at some point, you'll cap out. They can only make them so cheap, vs. cost of material.Injection molding is so quick, but milling aluminum takes operator and machine time. Plus, cleaning of the aluminum after it comes out of the machine (there's gunk on it from the cooling process as the machine cuts it.Of course, with injection molding, there may be cleaning of edges.Again, you just have to figure out how many you need. Would it be more economical to order what you need instead of spending the money for what the mold costs? Or is it cheaper to make the molds and have the parts injected molded?

author: LabSpokane
author_rank: Super Contributor
timestamp: June 19, 2015, 09:37:01 am
content: The pricing is very hard to quantify without actual models of all of your parts sent out for bid. What you want to tool may be cheap or very expensive. You also need to specify the life of the tool which can have a substantial impact.The price of the parts will also vary depending on the material you wish to use. An engineering resin can be quadruple the price of polystyrene.

author: coppice
author_rank: Super Contributor
timestamp: June 19, 2015, 10:18:04 am
content: Quote from: LabSpokane on June 19, 2015, 09:37:01 amSome materials, like polycarb, can be seriously expensive, but that isn't the end of it. Mould development for polycarb is usually way more expensive than for, say, ABS. People seem to go through multiple revisions before they come up with a mould that really behaves well, especially for clear polycarb.