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Small batch Manufacturing

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Hi all Just found this forum and spent the last three hou... - Dec 17, 2007 by Andy1975

Hello Andy, Please try to visit ... - Dec 17, 2007 by janz

You can spend a couple grand on a manual screen printer, or ... - Dec 17, 2007 by FD

Check out Sipad.com . I am in no way associated to these guy... - Dec 17, 2007 by Doug Philbrick

Stencils on average should be a low cost to you, compared to... - Dec 17, 2007 by Real Chunks

Whoa dude - slow down- maybe great beer money but if you don... - Dec 17, 2007 by mparker

Another tactic. Become friends with all the local solder pa... - Dec 17, 2007 by Dirk Nuendyke

In addition to what frank said, I have also just placed the ... - Dec 18, 2007 by wayne

Please consider this process as a solution. It truly was inv... - Dec 19, 2007 by Matt Kehoe

Andy, Without turning this into a sales pitch, I urge you... - Dec 19, 2007 by Matt Kehoe

I run a prototype/small-run shop, so I'll include some recom... - Dec 20, 2007 by isd.jww

Thanks for the posts everybody. I thinks this is all or n... - Dec 21, 2007 by Andy1975

Andy, I think you'll find as many answers to your questio... - Dec 21, 2007 by robgd3

> All or nothing You do not need to purchase everything a... - Dec 21, 2007 by isd.jww

Andy1975

#52910

Small batch Manufacturing | 17 December, 2007

Hi all

Just found this forum and spent the last three hours reading your posts!

I'm considering investing in a budget smt production line, and this is why: The company I work for manufacture very very small batches of boards, four a month for one product. This product is hand soldered and there are about 200 components per board, mostly chips and a couple of IC's. At the moment they hand solder them, spending about 6hours on each!, they also make about a dozen other boards.

I can buy a batch oven(heard all about them on here) and I would hand place the components. My only problem is the screen printing, as each stencil will be custom to the PCB, eating into the profit.

Can anybody suggest an alternative process, make your own stencil and even printer? Whats involved in making my own stencil with a laser cutter.

My company wants to sub some work out and I think a Saturday morning in my garage would manage the work, earning me some beer tokens.

Thanks

Andy

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janz

#52911

Small batch Manufacturing | 17 December, 2007

Hello Andy,

Please try to visit http://www.mechatronika.com.pl. They are manufacturing flexible solution for very small batches.

Regards janz

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#52912

Small batch Manufacturing | 17 December, 2007

You can spend a couple grand on a manual screen printer, or do what I did back in the day: place the board on the work bench and lay the stencil on the board. If you can hold it steady enough you can use a putty knife to apply your paste.

For the stencils, if you are doing them by hand or manual printing, you can get them in really small screens, so the cost is slightly less. There is also a universal frame where you only need to buy the screens.

Your boards don't sound terribly complicated, so an old Quad IVc or Zevatech 570 would be fine. I think both run on 110V, so you can even use it at home. I think this will be by far the biggest investment because of the feeders involved. Just be careful on buying old machines becuase spare parts are expensive and becoming harder to find.

For the oven, I have seen some really small "easy bake" type of ovens. I don't have any experience with any of them, buy they look so cute.

If you can hold out a few months, and want to take a trip to Las Vegas, then go to the APEX trade show, starting on April 1. You will be able to walk around and see items in all price ranges. The new entry level stuff is still available, but most people don't show it. Don't be scared to ask.

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Doug Philbrick

#52916

Small batch Manufacturing | 17 December, 2007

Check out Sipad.com . I am in no way associated to these guys but they will save you a bundle when it comes to doing what you want to do.

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Real Chunks

#52918

Small batch Manufacturing | 17 December, 2007

Stencils on average should be a low cost to you, compared to the other equipment you are buying. A couple hundred bucks (U.S.) is all you should be paying.

Making a stencil is harder than you would think. Set-up a visit with a local shop while negotiating price and see what really is involved. It truly is a science in itself.

Just remember that screen printing is the first step in your process. Everything else is based off it, so make sure it's done right.

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mparker

#52924

Small batch Manufacturing | 17 December, 2007

Whoa dude - slow down- maybe great beer money but if you don't have good environmental and ESD controls in your shed, all your suds slush fund will evaporate in RMA's costs. A small pick and place (table top) would do. A manual screen printer would help. (I got one cheap - write me back). Negotiate with stencil house - I get mine cheaper when playing one against the other. What pitch are your parts. If no fine pitch, then 6 mil. chemical etch stencil would work. If you have FPQFP - consider aspect ratio for solder volume.

Just a few thoughts.

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Dirk Nuendyke

#52933

Small batch Manufacturing | 17 December, 2007

Another tactic. Become friends with all the local solder paste reps, get them to buy you lunch, etc...but the key is...get them to give you free samples. That way you wouldn't have to BUY any paste.

As for the original fella, sounds like he's on a tight budget. This fella who sounds like owns his own business, 200-300 for a stencil might be alot...again, I don't know his full situation.

Anyway, I don't have personal experience with this, but look into table-top solder paste dispensing. If your designs are easy-peasy (nothing smaller than .080 x .050 chip components, or if your lead-to-lead spacing is 0.050" or greater on your active devices), table-top solder paste dispensing may be the way to go.

OTOH, if the designs in your company are stable, then investing in stencils and a manual or automated printer may be the way to go.

Here ya go. http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLR,GGLR:2006-19,GGLR:en&q=solder+paste+dispenser

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wayne

#52958

Small batch Manufacturing | 18 December, 2007

In addition to what frank said, I have also just placed the board on the work bench, but instead of trying to hold the board and stencil in place I would make a frame for the board using double sided tape, and after aligning I would tape the far edge of the stencil so that it would align to the next board to be printed. it worked well for me. good luck

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Matt Kehoe

#52966

Small batch Manufacturing | 19 December, 2007

Please consider this process as a solution. It truly was invented for your situation.

www.sipad.com

Matt Kehoe

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Matt Kehoe

#52967

Small batch Manufacturing | 19 December, 2007

Andy,

Without turning this into a sales pitch, I urge you to please consider this process for your challenge. It really was invented for your situation.

Small batch Manufacturing | 20 December, 2007

I run a prototype/small-run shop, so I'll include some recommendations too: 1) Don't buy a machine for just what you are doing today. Once you get into this field you will find demand to do more. 2) Don't scrimp on the stencil & machine. You will speed up your production and get better results with a decent setup. A manual printer will work fine for your production quantity. I use one made by LPKF. 3) The pick & place machine will be your largest expense, do your research. I'm on my second machine now and very satisfied with the Essemtec CSM7100V. It's not the fastest (~ 2200 pph), but does a good job. I've placed 0.5mm pitch parts without grief. Support is also very good. 4) The oven is no less important. What good is pasting & placing well if you don't solder the boards properly? A big part of this equation is the solder paste. I prefer no-clean paste so that I don't have the extra step of cleaning. For SnPb paste I prefer AIM. The oven can easily be your largest power consumption. Be careful with oven specs as some manufacturers do not actually specify max current, but instead specify idle current. There's a big difference.

Good luck!

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Andy1975

#53009

Small batch Manufacturing | 21 December, 2007

Thanks for the posts everybody.

I thinks this is all or nothing, I mean set up my own business doing this stuff or forget it. I've been involved in SMT for about 5 years now and feel pretty confident with the process stuff. Just curious to know how you price a job.

If I buy a production line, do I figure in paying for it in 2 years, factor that into the costing as well as everything else including my wages?

Is it common practise to supply all the components and if so what is the mark up on that?

Is there a book i can buy on all this?

Regards

Andy

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robgd3

#53012

Small batch Manufacturing | 21 December, 2007

Andy,

I think you'll find as many answers to your questions as you have people that post them.

To that end, here are mine: Planning to pay off the machine...we took it as an overhead cost, and didn't directly correlate cost of the machine to job costing. But...we do cost machine jobs differently than we cost manual labor jobs.

Basic job costing, for us, equals average shop-rate multiplied by the time to do the job. We have a per-component cost that varies depending on machine place, manual place, hand solder, wave solder, etc.

Supplying materials. It all depends. We run both types of jobs, consigned materials, and purchased materials. I know some shops that only do one or the other. It'll depend on your customer base. For purchased materials, we add a mark-up to the material cost to cover the overhead of managing the purchasing, and the inventory. For consigned material, we only charge labor.

Cheers ..rob

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isd.jww

#53016

isd_jwendell | 21 December, 2007

> All or nothing

You do not need to purchase everything all at once. You can start with the manual stencil printer and oven, which are the lower cost items and easiest to maintain. Placing parts by hand will be very time consuming, but you can do a few jobs while you are looking for the "right" pick and place machine. If you evaluate the time required for each phase of the run you'll see that unless you buy a realy kick-a$$ pick and place machine that the placement phase will consume the most time.

> ... paying for it in 2 years ...

I personally figure trying to pay for it in 5 years. I charge for machine time and my time (when appropriate).

> ... supply all the components ...

I too allow customers to provide parts, although this is not cost effective for the customer at times. I have had customers provide parts that are not placed in the reel properly so that the machine placement rate drops. The parts were cheaper "up-front" but end up costing more because of the low placement rate. For example, I received a reel of SMA diodes that were packaged too tightly in the carrier. They were so tight that I couldn't even get some of them out with tweezers! If the machine owner/operator buys the parts they tend to get volume discounts and can purchase parts that yield the best overall cost.

The owner/operator can also manage their inventory better instead of having a customer show up with a partial reel with no clue as to whether there are enough parts to do the job.

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