Interested in getting comfortable with SMT?

[EATyourGuitar]

The problem with Mouser is they're just not interested in small orders from the likes of us, so for the UK they charge a flat fee of £12/$20 for shipping making small value orders impractical, for bigger orders they're probably Ok as I think they do free shipping. The thing that annoys me is they have what appear to be UK and other European based sites, but all they do is give you the prices in your own currency, they still charge you international delivery.

I think, certainly with Taylor's goals in mind, the option of a kit is the way to go, make it as simple as possible for people to dip their toe in the SMT water.

so what your saying is that you are shocked that mouser has 80 languages available but does not operate 80 separate businesses?

But submitting a preformed BOM to Mouser is WAY simpler than picking out the components.  You upload the spreadsheet to their website and then order the full project.  The user doesn't have to select any components as the correct part numbers are already there.

Not saying that it is the best way to go, but I am trying to demystify it a bit. 

it gets even easier than that. you can build a BOM on mouser and share it as a link. when someone clicks the link, the parts are all added to the cart. this is one click DIY parts ordering. add up the time someone would spend at farnell even if they did have part numbers on a piece of paper. is saving $10 worth an hour of your time? most people will say yes. If I was selling kits, I would charge more than $5 to stuff all those envelopes and label them.

[R.G.]

The problem with Mouser is they're just not interested in small orders from the likes of us, so for the UK they charge a flat fee of £12/$20 for shipping making small value orders impractical,

(1) I do not think this statement is correct as stated, nor logically consistent.
- We do not know what Mouser is interested in without further proof. I find that they're fast and very efficient at shipping orders, and are interested in selling even one of something to me, and have been since their catalog was less than 10mm thick. My impression is that Mouser is eager to sell to anyone, in any quantity that allows them to do good business. They have been that way for a couple of decades.
- It is certain that it costs more to ship internationally in small quantities. They are a business, and so they will not effectively give you money by selling below their total cost, including shipping and the cost of the paperwork.
- Your statement implies that they're trying to discourage you from buying. If you feel that way, don't buy from them. It makes both you and them happy. Would it feel better if you could see the parts on line, but when you wanted to buy, they simply said "we don't ship to you at all because it would cost too much and we respect you too much to charge you what it would cost us to do it."?
It ain't personal. If you don't like their prices, buy elsewhere. The reason Mouser gets mentioned so often is based on the fact that they are fast, cost-effective, and efficient for many buyers. There may be exceptions.

for bigger orders they're probably Ok as I think they do free shipping.

"Free shipping" means "We've hidden the cost of shipping inside the cost of goods".

The thing that annoys me is they have what appear to be UK and other European based sites,

There is no real link between where an internet site appears to be and where the goods are shipped from. As we have all learned, appearances on the internet are at best worthless, and at worst malicious.

but all they do is give you the prices in your own currency, they still charge you international delivery.

Giving you prices in your own currency is probably them trying to be polite and helpful, telling you what it costs in your local currency, which is something you'd otherwise have to do for yourself, with an online currency converter, yes? If they gave you prices in only US$, you (or certainly a lot of someones) would be offended that they did not respect your national origin enough to quote prices in your local currency, right? If they gave you prices only in some other currency, from halfway around the globe, they'd appear to be obstructive, yes? If the gave you prices in - oh, heck, let's just say yen - the very next thing you'd do after getting the price in yen is to convert that to your local currency to find out how much it really costs, yes? So why isn't it good for them to just tell you what the tab is in currency you have?

And as we all know, the price delivered in our country is always going to have shipping charges added. Even if we buy in the grocery store down the block, *they* have paid shipping, and are going to add it onto the price you pay. If Mouser does not have local warehouses filled up with stock from the original manufacturer, set up right in your country, they're going to have to charge you international shipping to get it to you. I'm guessing that this is the case.

My impression is that Mouser is very eager to make it easy and effective to buy stuff there. If they thought they could sell more and make more money by having a local warehouse and not charging you international shipping (other than that bringing the big boxes to the warehouse), they'd probably do it. So the way to get this to stop happening is to order more from them, until they have enough volume to set up that local warehouse. Right?

[J0K3RX]

btw - may have already been mentioned but, you can buy resistor/capacitor kits on ebay with almost every value... If somebody could create/build a checkout list to the same on mouser/digi-key/jameco etc even better! Then you could click on the link and all of the different value resistors/caps would be in your cart and you could choose what you want and the quantity or, you could choose them all and the quantity and have a complete stock of SMT parts. all 1206 would be good! This could be done with IC's as well..  

Also you can get plated through-hole proto board which is perfect for surface mount! With that you wouldn't have to worry about spanning traces and you could design double sided with the option of using through-hole components as well...

For example: You could get without the switch as well
http://www.ebay.com/itm/Guitar-Effects-Pedal-Design-Kit-1546-/390455327661?pt=Guitar_Accessories&hash=item5ae8f37bad

Check this out
http://vakits.com/

[Ronan]

Another alternative is to get 0805 parts and SOIC chips from Tayda. $1.00 for 100 of one value of resistor or capacitor. 18c to 50c each for dual opamps.

I recently put some 0805 resistors on a through-hole pcb with 0.1" spacing for vertical mount resistors. It worked fine, even though I've never done it before. It really is true, that thinking about it is more difficult than doing it. I used a standard soldering iron and standard 0.7mm (0.28") solder.

One trick I discovered is to use "helping hands" to put a little bit of weight on the component to hold it there while soldering, just using the tip of one of the crocodile clips to bear down on an IC or resistor. This made it easy to do the first solder joint on a resistor, or the corner legs of an IC.

They arent so bad! (as long as you have tweezers and a microscope  ). But seriously, the 0805 that tayda carry are pretty easy to work with.

I've been dabbling in this recently for the same reasons you have posted here. Its obvious the components are going to change over and once you get into it, its actually pretty fun. I have a few easy layouts if anyone wants me to upload them. And I'd be happy to take a request or two to get some more practice in!

Given that Taylor is tied down at the moment with some high priority projects, I have some suggestions to get Taylor's idea moving forward:

1. Mike (tyronethebig), perhaps you could upload a couple of SMT layouts?

2. I wouldn't mind doing a layout and gerbers so someone else could get 2" x 2" pcb's made at Seeedstudio, total cost $14.00 for 10 pcb's, with 3 to 4 weeks turnaround time. I might need some pointers with layout since I am new to SMT. I would prefer someone else to get the pcb's made and send them out.

3. Recycle - I have a few "coaster" pcb's suitable for practising SMT. They have defects ranging from minor to major. I could send them out for $5 including shipping, one is a test phaser module without LFO (incomplete) including a dual power supply, it worked initially, then played up, and I haven't been back to revisit it yet. The other one is a negative earth parapedal with a couple minor errors including offset silkscreen, but works fine. They could be put to good use to learn a bit of SMT soldering, if nothing else.

All the vertical mount resistors could be done in 0805 SMD in this parapedal pcb, that was my intention but the resistors did not arrive in time.
Here's the phaser pcb. I put the SMT resistors and caps over 0.1" through-hole spacing on this one, could be neater, this was my first pcb with SMT resistors and caps.

[chromesphere]

ive been thinking of replaceing some throughhole resistors and caps on a few of more boards (clone stuff) with SMD to save some room.  Looking at the size of 0805 compared to throughhole in DipTrace, the size difference is about half, but i reckon i could pull it off....Might have to give it a try next time i build some!
Paul

[kingswayguitar]

btw - may have already been mentioned but, you can buy resistor/capacitor kits on ebay with almost every value... If somebody could create/build a checkout list to the same on mouser/digi-key/jameco etc even better! Then you could click on the link and all of the different value resistors/caps would be in your cart and you could choose what you want and the quantity or, you could choose them all and the quantity and have a complete stock of SMT parts. all 1206 would be good! This could be done with IC's as well..  

Also you can get plated through-hole proto board which is perfect for surface mount! With that you wouldn't have to worry about spanning traces and you could design double sided with the option of using through-hole components as well...

For example: You could get without the switch as well
http://www.ebay.com/itm/Guitar-Effects-Pedal-Design-Kit-1546-/390455327661?pt=Guitar_Accessories&hash=item5ae8f37bad

Check this out
http://vakits.com/

thumbs up for vakits - nightfire electronics
used him/her with good results

[earthtonesaudio]

Make your own hot air soldering gun: http://www.piclist.com/techref/hotairpencil20usd.htm
Simple solder paste + hot air example: http://www.youtube.com/watch?v=0O2UEGLJeAI

Some examples of hand-soldering ICs using traditional iron and wound solder: http://www.youtube.com/watch?v=5uiroWBkdFY (check out the kapton tape example)


For me the hardest part of SMT is finding the right components.

[R.G.]

For those not familiar with Electronic Goldmine, it's worth a look. If you want to learn to solder SMD parts, they stock a number of SMD kits. They're not simple overdrives, but they do the primary job of letting you work on the manual skills of soldering.

See:
http://www.goldmine-elec-products.com/prodinfo.asp?number=C6719
http://www.goldmine-elec-products.com/prodinfo.asp?number=C6736
http://www.goldmine-elec-products.com/prodinfo.asp?number=C6736
http://www.goldmine-elec-products.com/prodinfo.asp?number=C6725

[Ice-9]

Make your own hot air soldering gun: http://www.piclist.com/techref/hotairpencil20usd.htm
Simple solder paste + hot air example: http://www.youtube.com/watch?v=0O2UEGLJeAI

Some examples of hand-soldering ICs using traditional iron and wound solder: http://www.youtube.com/watch?v=5uiroWBkdFY (check out the kapton tape example)


For me the hardest part of SMT is finding the right components.

Good links Earthtonesaudio. the 3rd link is pretty much how I do it, but for removal and repairs of high pin count IC's I tend to use a hot air iron and a feeler guage (used in car spark plug gap measurement)  to slide under the chip to apply a little upward pressure while removing the IC.

I also find this pretty cheap tool worth it's weight in gold for SMT

http://www.pro-iroda.com/pro120.htm

[Jdansti]

Good ideas!

Seems like the hot air nozzles on these Weller Portasol butane soldering irons might work.  You'd have to make sure the flame is low, otherwise you'd be cooking instead of soldering. 



Nozzles and plastic cutter:


BTW- mine clogged up, and when I called Weller customer support to ask how to fix it, they told me, but they also sent me a brand new one in the mail!  No receipt or hassle. Great company! 

[pickdropper]

If somebody is interested at having a go at some SMT pedal circuits, I have some boards left from some verified prototype runs.  At the moment, I have Screwdriver boards where all the transistors are through-hole but everything else is SMT.  I also have some Deep Blue Delay boards (entirely SMT).  I have BOMs with Mouser Part Numbers for both of them.  The only exception is the PT2399S, which Mouser doesn't carry (but Small Bear and Mammoth do).  Just shoot me a PM.

[Ice-9]

Good ideas!

Seems like the hot air nozzles on these Weller Portasol butane soldering irons might work.  You'd have to make sure the flame is low, otherwise you'd be cooking instead of soldering. 



Nozzles and plastic cutter:


BTW- mine clogged up, and when I called Weller customer support to ask how to fix it, they told me, but they also sent me a brand new one in the mail!  No receipt or hassle. Great company! 

Yes indeed, my post above yours also points to one of those but for the Irodo iron which is better, I have used both and there best used hot, but quick. If your temp is too low they you just sit there slow boiling the IC and not melting the solder. If it's hot it melts solder in a matter of seconds without getting the chip exposed to heat for a long time., but it takes practice and everyone will have a prefered way.

[Ice-9]

If somebody is interested at having a go at some SMT pedal circuits, I have some boards left from some verified prototype runs.  At the moment, I have Screwdriver boards where all the transistors are through-hole but everything else is SMT.  I also have some Deep Blue Delay boards (entirely SMT).  I have BOMs with Mouser Part Numbers for both of them.  The only exception is the PT2399S, which Mouser doesn't carry (but Small Bear and Mammoth do).  Just shoot me a PM.

Can you post a picture of the Deep blue delay boards please.

[octfrank]

Yes indeed, my post above yours also points to one of those but for the Irodo iron which is better, I have used both and there best used hot, but quick. If your temp is too low they you just sit there slow boiling the IC and not melting the solder. If it's hot it melts solder in a matter of seconds without getting the chip exposed to heat for a long time., but it takes practice and everyone will have a prefered way.

I would disagree here, hot and fast can cause thermal stress damage to the IC, normal temp curves for smt soldering show a 1 - 3 minute preheat time then a shorter time at a higher temp to melt the solder. I typically hold the heat gun further away from the chip for a minute or two to evenly heat the entire area then bring it in a bit closer to melt the solder. It is not the heat that damages the chips, it is the sudden change or unequal distribution of heat that does.

[pickdropper]

Yes indeed, my post above yours also points to one of those but for the Irodo iron which is better, I have used both and there best used hot, but quick. If your temp is too low they you just sit there slow boiling the IC and not melting the solder. If it's hot it melts solder in a matter of seconds without getting the chip exposed to heat for a long time., but it takes practice and everyone will have a prefered way.

I would disagree here, hot and fast can cause thermal stress damage to the IC, normal temp curves for smt soldering show a 1 - 3 minute preheat time then a shorter time at a higher temp to melt the solder. I typically hold the heat gun further away from the chip for a minute or two to evenly heat the entire area then bring it in a bit closer to melt the solder. It is not the heat that damages the chips, it is the sudden change or unequal distribution of heat that does.

Yeah, this is closer to a real reflow profile.  Another option is to pre-heat with a hot plate and then come in with the heat gun.

There are also inexpensive Chinese reflow ovens.  They aren't fantastic, but they are a bit easier than using a heat gun as they have pre-programmed reflow profiles built in.

[pickdropper]

If somebody is interested at having a go at some SMT pedal circuits, I have some boards left from some verified prototype runs.  At the moment, I have Screwdriver boards where all the transistors are through-hole but everything else is SMT.  I also have some Deep Blue Delay boards (entirely SMT).  I have BOMs with Mouser Part Numbers for both of them.  The only exception is the PT2399S, which Mouser doesn't carry (but Small Bear and Mammoth do).  Just shoot me a PM.

Can you post a picture of the Deep blue delay boards please.

I'll try and get a better photo up later (I'm on my phone now) but you can see the board in the pictures thread.  It is in my build with the red box with the Swiss Army knife logo on it.

[chi_boy]

Nozzles and plastic cutter:

Do you think that deflector could be used to tin a PCB?  I'm wondering if you cold heat it up, melt some solder on the rounded outside part and then drag it across the traces to tin them.  Maybe with some flux on the board first.  I almost want to buy one just to try.

[chi_boy]

- A kit with all the SMT parts so you don't have to worry about sourcing each individual resistor, etc.

Let me know if something like this appeals to you.

I would jump on this option.



Also, I know there are different package sizes of SMD parts, but there doesn't really seem to be a concensus among DIY builders regarding what size to use.  It's tough keeping well stocked with through hole parts like resistors for example.  Now imagine trying to stock all those values in 3 different package sizes for SMD projects.  The thought of buying parts for a SMD project or multiple projects seems a little daunting.  Or am I overthinking again?

[pickdropper]

- A kit with all the SMT parts so you don't have to worry about sourcing each individual resistor, etc.

Let me know if something like this appeals to you.

I would jump on this option.



Also, I know there are different package sizes of SMD parts, but there doesn't really seem to be a concensus among DIY builders regarding what size to use.  It's tough keeping well stocked with through hole parts like resistors for example.  Now imagine trying to stock all those values in 3 different package sizes for SMD projects.  The thought of buying parts for a SMD project or multiple projects seems a little daunting.  Or am I overthinking again?

Well, resistors aren't too bad as they are very inexpensive.  I tend to use 0603, but you are correct that there is no consensus.

Most ceramic caps aren't too expensive either, although they get pricier as they get more dense.  I mostly use 0805 caps, but I occasionally use 1206 for 47uF caps instead of using Tantalums.

[R.G.]

Do you think that deflector could be used to tin a PCB?  I'm wondering if you cold heat it up, melt some solder on the rounded outside part and then drag it across the traces to tin them.  Maybe with some flux on the board first.  I almost want to buy one just to try.

Simpler and cheaper to use mass, not continuous heat.

Get a length of brass pipe at the hardware store.  Clean the outside carefully, flux and tin it with the heat from a propane torch or a kitchen burner. For extra points, bend yourself up a U-shaped handle passing through the center of the pipe ... before ... you start heating it.  

Once it's tinned, you can tin a board by putting flux on the copper traces, then heating the pipe to above solder-melt temp and loading the pipe up with solder, then swiping it across the copper. Tinned board.