X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 30 [X] Return-Path: Received: from ms-smtp-05.southeast.rr.com ([24.25.9.104] verified) by logan.com (CommuniGate Pro SMTP 5.1.6) with ESMTP id 1842920 for flyrotary@lancaironline.net; Fri, 16 Feb 2007 21:13:33 -0500 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.104; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-103-061.carolina.res.rr.com [24.74.103.61]) by ms-smtp-05.southeast.rr.com (8.13.6/8.13.6) with SMTP id l1H2Cevm010803 for ; Fri, 16 Feb 2007 21:12:40 -0500 (EST) Message-ID: <000701c75239$1dc6cd90$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: SMD Printer Photo 2 Date: Fri, 16 Feb 2007 21:12:46 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0004_01C7520F.3493B170" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3028 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0004_01C7520F.3493B170 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I agree, Mike, there are indeed some really neat SMD devices and tools = out there - but, most are just too expensive for the hobbyist. I = drooled over several nights just pouring over them. Yes, many article on the web about supposedly how to do that. The = critical parameters seem to be squeegee angle with the board, thickness = of the stencil, hardness of the squeegee, viscosity of the solder paste, = and pressure of the squeegee on the stencil. Probably others, but those = are the ones I recall. Just pick and place machines that just pluck those SMD components off of = reels and place them on the board are one of the items that caused a bit = of drooling. But, on the other hand if a solder paste run smears or is other wise = unsatisfactory, you can clean off the board with alcohol and have = another try at it. {:>) Nothing is locked in until you stick it in the = oven. After that then a lot of work to change/remove anything in the = wrong place. Ed ----- Original Message -----=20 From: Michael LaFleur=20 To: Rotary motors in aircraft=20 Sent: Friday, February 16, 2007 9:03 PM Subject: [FlyRotary] Re: SMD Printer Photo 2 We produce and test a lot of boards that are all SMDs and fine pitch = devices. Getting that solder paste on the correct thickness is an art = form. Even with a tightly controlled manufacturing process and state of = the art equipment, there are often problems. I saw a real nice pick-n-place machine for placing somponents on = circuit boards go at auction for $500. It was probably worth 100 times = that. If I were in California, I'd have bought it. Mike LaFleur ----- Original Message ---- From: Ed Anderson To: Rotary motors in aircraft Sent: Friday, February 16, 2007 6:25:18 PM Subject: [FlyRotary] Re: SMD Printer Photo 2 Hi Bill, there are a number of places that will make stencils - but = cheaper plastic ones a bit harder to find. You take a CAD drawing for your circuit board - most use DXF format = but they can be make from Gerber files (my Circuit Board drawing = software does not produce gerber files, but will export a DXF file). =20 I then eliminate anything in the DXF file that is not a pad or pin = that I want solder on. Then e mail the file to this company/guy. = http://www.pololu.com/ attn : Jan Malasek They use a laser to cut the = stencil based on your DXF file and ship it to you. Oh, they first send = you a PDF of the proposed stencil for one last check by you before = cutting the stencil. Here is the webpage that explains their process. = http://www.smtstencil.com/ The one I got matches even the 30 pins of a fine pitch socket with = pins only 0.25mm apart, so I was pleased. You can see some result of = the laser heat on the plastic so its not quite as clean as with a metal = stencil - but quite good for the price. =20 Ed ----- Original Message -----=20 From: Bill Schertz=20 To: Rotary motors in aircraft=20 Sent: Friday, February 16, 2007 4:52 PM Subject: [FlyRotary] Re: SMD Printer Photo 2 Ed, Very nice printer you made -- how do you get your stencils? Bill Schertz KIS Cruiser # 4045 ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Friday, February 16, 2007 2:55 PM Subject: [FlyRotary] Re: SMD Printer Photo 2 Hi Bill, To answer your question, Yes. And I am certain they can be made = to do the job. In fact, before the stencils arrived on the SMD scene, = it appears they used a "Mesh screen" which I understand is very close to = what the silkscreen printers do.=20 But, the "mesh screen" approach was limited by the smallest pitch = of pins they could resolve to, so they went to the stencil approach. With the solder paste method (from what I think I understand) = appears to require some consistency of pressure for best results. That = lead to my adjustable springs to put the squeegee under consistent = pressure - supposedly once I find that magic pressure setting then = consist good result will follow. Lots of ways to skin this cat. Ed ----- Original Message -----=20 From: wrjjrs@aol.com=20 To: Rotary motors in aircraft=20 Sent: Friday, February 16, 2007 3:41 PM Subject: [FlyRotary] Re: SMD Printer Photo 2 Ed, That looks like innovative and neat work. Now the apparatus = begs the question, have you ever looked at a standard silkscreen jig = from the art store to do the same job? The design you made is = considerably tougher, but some of the silkscreen machines are pretty = well framed using hardwood. FWIW (which probably aint much) Bill Jepson =20 -----Original Message----- From: eanderson@carolina.rr.com To: flyrotary@lancaironline.net Sent: Fri, 16 Feb 2007 11:19 AM Subject: [FlyRotary] SMD Printer Photo 2 This shows one of the two side mounts of my SMD solder paste = printer which is attached to the MSD nylon strip which rides in a groove = inside the cheap T track. The T track is simply screwed to the 1/2" = slab of aluminum. The acorn nut provides tension through a 1/4" threaded = rod and keeps the pull-handle gripped between the two sides and provides = tension on the side plate which puts side pressure on the MSD strip in = the T rail. More pressure makes the device slide slower and less makes = it faster. =20 The squeegee holder can pivot to either put the squeegee down on = the bed or to hold it up off of it after a solder run and you want to = move the squeegee holder back to the other original end of the board = without smearing your deposited paste. The second photo shows where the squeegee holder would be = positioned after a "solder-run" was made. I would then rotate the = squeegee up 1/8" inch out of contact with the bed and move it back to = the other (starting) end of the bed. Ed The message is ready to be sent with the following file or link = attachments: MVC-007F.JPG Note: To protect against computer viruses, e-mail programs may = prevent sending or receiving certain types of file attachments. Check = your e-mail security settings to determine how attachments are handled.=20 --Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ [Image Removed]=20 [Image Removed]=20 ------------------------------------------------------------------------ Check out the new AOL. Most comprehensive set of free safety and = security tools, free access to millions of high-quality videos from = across the web, free AOL Mail and more. ------=_NextPart_000_0004_01C7520F.3493B170 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I agree, Mike, there are indeed some = really neat=20 SMD devices and tools out there - but, most are just too expensive for = the=20 hobbyist.  I drooled over several nights just pouring over=20 them.
 
Yes, many article on the web about = supposedly how=20 to do that.  The critical parameters seem to be squeegee angle with = the=20 board, thickness of the stencil, hardness of the squeegee, viscosity of = the=20 solder paste, and pressure of the squeegee on the stencil.  = Probably=20 others, but those are the ones I recall.
 
Just pick and place machines that just = pluck those=20 SMD components off of reels and place them on the board are one of the = items=20 that caused a bit of drooling.
 
But, on the other hand if a solder = paste run smears=20 or is other wise unsatisfactory, you can clean off the board with = alcohol and=20 have another try at it. {:>)  Nothing is locked in until you = stick it in=20 the oven.  After that then a lot of work to change/remove anything = in the=20 wrong place.
 
 
Ed
----- Original Message -----
From:=20 Michael LaFleur
Sent: Friday, February 16, 2007 = 9:03=20 PM
Subject: [FlyRotary] Re: SMD = Printer=20 Photo 2

We=20 produce and test a lot of boards that are all SMDs and fine pitch = devices.=20 Getting that solder paste on the correct thickness is an art form. = Even with a=20 tightly controlled manufacturing process and state of the art = equipment, there=20 are often problems.

I saw a real nice pick-n-place machine for = placing=20 somponents on circuit boards go at auction for $500. It was probably = worth 100=20 times that. If I were in California, I'd have bought it.

Mike=20 LaFleur

-----=20 Original Message ----
From: Ed Anderson=20 <eanderson@carolina.rr.com>
To: Rotary motors in aircraft=20 <flyrotary@lancaironline.net>
Sent: Friday, February 16, 2007 = 6:25:18=20 PM
Subject: [FlyRotary] Re: SMD Printer Photo 2

Hi Bill, there are a number of places = that will=20 make stencils - but cheaper plastic ones a bit harder to = find.
 
You take a CAD drawing for your = circuit board -=20 most use DXF format but they can be make from Gerber files (my Circuit = Board=20 drawing software does not produce gerber files, but will export a DXF=20 file). 
I then eliminate anything in the DXF = file that is=20 not a pad or pin that I want solder on.  Then  e mail = the  file=20 to this company/guy.  http://www.pololu.com/   attn : Jan=20 Malasek  They use a laser to cut the stencil based on your DXF = file and=20 ship it to you.  Oh, they first send you a PDF of the proposed = stencil=20 for one last check by you before cutting the stencil.
 
Here is the webpage that explains = their=20 process.   http://www.smtstencil.com/
 
The one I got matches even the 30 = pins of a fine=20 pitch socket with pins only 0.25mm apart, so I was pleased.  You = can see=20 some result of the laser heat on the plastic so its not quite as clean = as with=20 a metal stencil - but quite good for the price. 
 
 
Ed
-----=20 Original Message -----
From:=20 Bill Schertz
To:=20 Rotary=20 motors in aircraft Sent:=20 Friday, February 16, 2007 4:52 PM Subject:=20 [FlyRotary] Re: SMD Printer Photo 2

Ed,
Very nice printer you made -- how do you get = your=20 stencils?
Bill Schertz
KIS Cruiser # 4045
-----=20 Original Message ----- From:=20 Ed Anderson To:=20 Rotary motors in aircraft Sent:=20 Friday, February 16, 2007 2:55 PM Subject:=20 [FlyRotary] Re: SMD Printer Photo 2

Hi Bill,
 
To answer your question, = Yes.  And I am=20 certain they can be made to do the job.  In fact, before the = stencils=20 arrived on the SMD scene, it appears they used a "Mesh screen" = which I=20 understand is very close to what the silkscreen printers do. =
 
But, the "mesh screen" approach = was limited=20 by the smallest pitch of pins they could resolve to, so they went = to the=20 stencil approach.
 
With the solder paste method = (from what I=20 think I understand) appears to require some consistency of = pressure for=20 best results.  That lead to my adjustable springs to put the = squeegee=20 under consistent pressure - supposedly once I find that magic = pressure=20 setting then consist good result will follow.
 
Lots of ways to skin this = cat.
 
Ed
-----=20 Original Message ----- From:=20 wrjjrs@aol.com To:=20 Rotary motors in aircraft Sent:=20 Friday, February 16, 2007 3:41 PM Subject:=20 [FlyRotary] Re: SMD Printer Photo 2

Ed, That looks like innovative and neat work. Now the = apparatus=20 begs the question, have you ever looked at a standard silkscreen = jig=20 from the art store to do the same job? The design you made is=20 considerably tougher, but some of the silkscreen machines are = pretty=20 well framed using hardwood. FWIW (which probably = aint=20 much)
Bill Jepson
 
 
-----Original Message-----
From:=20 eanderson@carolina.rr.com
To: = flyrotary@lancaironline.net
Sent:=20 Fri, 16 Feb 2007 11:19 AM
Subject: [FlyRotary] SMD Printer = Photo=20 2

This shows one of the two side mounts of = my SMD=20 solder paste printer which is attached to the MSD nylon strip = which=20 rides in a groove inside the cheap T track.  The T track is = simply=20 screwed to the 1/2" slab of aluminum. The acorn nut provides = tension=20 through a 1/4" threaded rod and keeps the pull-handle gripped = between=20 the two sides and provides tension on the side plate which puts = side=20 pressure on the MSD strip in the T rail.  More pressure = makes the=20 device slide slower and less makes it faster.  =
 
The squeegee holder can pivot to either = put the=20 squeegee down on the bed or to hold it up off of it after a = solder run=20 and you want to move the squeegee holder back to the other = original end=20 of the board without smearing your deposited paste.
 
The second = photo shows=20 where the squeegee holder would be positioned after a = "solder-run" was=20 made.  I would then rotate the squeegee up 1/8" inch out of = contact=20 with the bed and move it back to the other (starting) end of the = bed.
 
Ed
 
 
The message is ready to be sent with the = following file=20 or link attachments:
MVC-007F.JPG

Note: To protect = against=20 computer viruses, e-mail programs may prevent sending or = receiving=20 certain types of file attachments.  Check your e-mail = security=20 settings to determine how attachments are handled.

[Image = Removed]=20
[Image = Removed]=20
Check out the new AOL. = Most=20 comprehensive set of free safety and security tools, free access = to=20 millions of high-quality videos from across the web, free AOL = Mail and=20 = more.

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