Need a budget (but effective) light commercial SMD assembly line. - Page 1
Forum section: electronics / general

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: August 14, 2019, 09:24:36 pm
content: Hello! New to these forums. Long time tinkerer and inventor of random shit that annoys my wifeSo one of my designs is taking off, and I need to start manufacturing them.I am unwilling to farm it out to China, just to get that up front.I currently have an ultrasonic cleaner (sweep & degas functions, heated, etc) for the cleaning, ionized/filtered compressed air for blowing them off, (haven't hit on a RO/DI water system yet, using distilled for rinsing/cleaning), I have a manual PNP assist gantry thing I made to help steady myself for placing components on PCBs, and I just use hand-held hot air to reflow currently. All works fine for prototypes and one-offs, but I've now outgrown it.I will get some early editions out still by hand, but I need to quickly invest in a budget friendly, yet effective SMD assembly line.I have 2 boards to make: one is 150x250mm, 2 sided, about 500 components (about 60 unique), some of which are THT which I will have to just solder by hand. Multiple ICs, from PLCC44 to SOIC-18 and some others. The other board is 30x30mm, about 30 components, about 15 unique, one THT connector.They will be coated with urethane conformal coating as they will be used outdoors.I don't need to produce a great many boards, say 10/wk of the large and 75 of the small. Enough to where I'm not sure I physically CAN do all those by hand, but I don't need to invest in a crazy fast, 4+ head PNP either. The PNP will NOT be my bottleneck.It seems I've read everything and everything else, and I find it to be either the cheap Chinese IR reflow ovens and their $3k PNP machines (with questionable reliability...) or step it WAAAAAY up with the big boy stuff. Budget is somewhat flexible, and I have NO problems upgrading later if/when things really get going, but I also don't want to buy junk that I will spend more time fighting than actually producing complete boards (BT/DT with a cheap 3D printer...). I would like to stay around $10k USD or less if possible.What out there would be best for me?Thanks in advance!

author: rea5245
author_rank: Frequent Contributor
timestamp: August 14, 2019, 09:33:37 pm
content: Have you considered using a US assembler? It's a lot more expensive than China, but it might be less expensive than buying all the equipment you need, and certainly it's less hassle.- Bob

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: August 15, 2019, 02:41:47 am
content: Quote from: rea5245 on August 14, 2019, 09:33:37 pmI did get in touch with a couple places, the relatively low amount I need isnt cost effective for them to do.

author: mrpackethead
author_rank: Super Contributor
timestamp: August 15, 2019, 03:41:33 am
content: Did you try macrofab?A $10k budget is going to put you in the realm of a new chinese machine that going to be annoying making that many boards. If i had a dollar for everyone whos tryed this, and then has ended up investign the $30-40k to do it properly... i'd be rich.

author: SWR
author_rank: Regular Contributor
timestamp: August 15, 2019, 07:12:51 am
content: I had similar requirements with no huge volumes and limited physical space for the setup.I ended up with the following setup:Home made screen printer (parts from Aliexpress $70)- Springloaded holder for frameless stencils- Adjustable X, Y and roation.- Guided squeegee angle on roller bearing rails.- Speed and pressure is manual for now (option for adding weights later).SmallSMT VP-2500DP WNE pick & place machine ($6990)- 78 reels- 18 tape strips- 107 tray compartments- 7 sticks- 6 nozzle with autochangeImdes Mini Condens-IT vapor phase reflow soldering machine ($699)- The manual says 170x240mm maximum PCB size- You can fit a 150x250mm PCB but not much bigger than that- The Jumbo model is several times the price.Good luck with your small scale production.Soren

author: mrpackethead
author_rank: Super Contributor
timestamp: August 15, 2019, 10:35:24 am
content: Quote from: SWR on August 15, 2019, 07:12:51 amHi Soren, I'd love to see a pic of how you are holding frameless stencils.

author: spongle
author_rank: Regular Contributor
timestamp: August 15, 2019, 12:01:32 pm
content: Quote from: SWR on August 15, 2019, 07:12:51 amWould also love details of your paste printer build, but where did you find the oven so cheap? The only source I've seen is in Europe, and more than 2X that price?

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: August 15, 2019, 02:10:01 pm
content: Quote from: SWR on August 15, 2019, 07:12:51 amHow are you liking that PNP machine? It is right at the zone I was hoping to be at: quality (well, you tell me), decent price, enough reels to not have to switch out for the different PCBs (and a bit of room for expansion), AND some vibration feeders and IC tray options. Seems perfect.And yes, some more info on your stencil setup please!

author: mrpackethead
author_rank: Super Contributor
timestamp: August 15, 2019, 10:14:27 pm
content: I have seen a 'quikframe' but it was for 29" x 29" full size stencils.

author: SMTech
author_rank: Frequent Contributor
timestamp: August 15, 2019, 10:50:40 pm
content: There are several common stencil framing systems that allow you to buy a foil on its own (with some special features) and then tension it as needed. Many of them will come in several sizes, although 23" & 29" will be the most common.The biggest is probably DEKs VectorGuard, then there are Zelflex from LKPF, Alpha TensoRed, Alpha Tetra& QuattroFlex, most of the need compressed air to operate and some maintenance. Some stencil manufacturer may have their own systems as well to avoid the fees associated with some of the others.

author: mrpackethead
author_rank: Super Contributor
timestamp: August 15, 2019, 11:47:31 pm
content: http://www.quickstencil.com/Products/Low-Profile-29x29-Frame-Adapter__LowPro29x29Adapter.aspxThe quickframe system uses a stencil that is only tensioned in one direction, and it is tensioned mechanically with set screws. Its not bad. but not as good as a framed stencil. I wonder if its possible to build the a frame that works in a similar way but tensions in both directions.The cost cost Chinse fabs do a pretty 'good' job for most things, and they will cut a stencil to shape if you provide the gerbers.

author: SWR
author_rank: Regular Contributor
timestamp: August 16, 2019, 08:02:32 am
content: Quote from: mrpackethead on August 15, 2019, 10:35:24 amThe first attachment is a detail of the stencil clamp where the MGN9C stainless steel rail has been removed.M4 rivet nuts are inserted from the bottom of the 3D printed counterpart for every 20mm.The top of the rivet with 5,4mm external diameter is protruding up into the MGN9C rail that is mounted upside down.The rail is fixed with M4x8mm knurled head bolts.I order the stencils with a row of 20mm spacing 5,5mm holes at both ends.I have attached pictures of some of the parts used, but more details are available here:https://www.eevblog.com/forum/manufacture/idea-for-a-diy-stencil-printer/msg2258337/#msg2258337Best regardsSoren

author: SWR
author_rank: Regular Contributor
timestamp: August 16, 2019, 08:52:46 am
content: Quote from: Rat_Patrol on August 15, 2019, 02:10:01 pmI'm very happy with the machine, but have mainly done testruns until now.I'm still working on getting the whole design flow and PCB libraries prepared for stremlining the setup.I keep getting sidetracked by family, holidays, golf and music.The build quality is better than expected, but I don't have any previous experience so my reference point is weak.I assume a 100K machine is even better, but it's built very heavy. I managed to get it from the floor to the table by myself and a lot of sweat by pivoting the floor board onto the table.QuoteI have attached some pictures of the spring loading parts on the 8mm rails and the magnetic standoffs.Let me know if there's anything else in the design that is unclear?Feel free to use what you like and improve what you don't like.Best regardsSoren