SMD Soldering Test
SMD Soldering Test
So, being winter with a bit of spare time up my sleeve, I quickly draw up a simple PCB that incorporates some resistors and LEDs of various sizes: 1206, 0805, 0603, 0402 and 0201. I couldn't easily find any 0201 LEDs on Aliexpress, so I reuse a 0402 LED. With a momentary button and a battery this all fits onto a 28mm round PCB. I have just sent it off to Seeed for manufacture at a cost of A$25.49 (90+ boards), so it should be back in 18-24 days time.
R5 will be the challenge part.
A picture tells a thousand words, so...
Front - the fun part:
The back:
R5 will be the challenge part.
A picture tells a thousand words, so...
Front - the fun part:
The back:
Re: SMD Soldering Test
As you can see this is a very simple PCB. Just for fun I had KiCAD produce a 3D view of the PCB:
And here is the circuit diagram:
As a test, I have tried to track the Build of Materials (BOM) and costs etc. As of today it's running at $1.69, however, that doesn't include a 40cm length of 0.3mm solder or packaging, so hopefully I can keep the BOM under A$2.00. Of course, this doesn't include any labour costs as this is just a hobby thing.
For those that are interested, attached below is a zip file containing all the projects files, ie: KiCAD 4.0.7 files, images and spreadsheet etc. These might will need upgrading to be used on the soon-to-be-released version 5.
And here is the circuit diagram:
As a test, I have tried to track the Build of Materials (BOM) and costs etc. As of today it's running at $1.69, however, that doesn't include a 40cm length of 0.3mm solder or packaging, so hopefully I can keep the BOM under A$2.00. Of course, this doesn't include any labour costs as this is just a hobby thing.
For those that are interested, attached below is a zip file containing all the projects files, ie: KiCAD 4.0.7 files, images and spreadsheet etc. These might will need upgrading to be used on the soon-to-be-released version 5.
- Attachments
-
- SMD-Soldering_Test_PCB_Ver1.0.zip
- (261.54 KiB) Downloaded 565 times
Re: SMD Soldering Test
Noice!!
Re: SMD Soldering Test
I had the PCB's produced by Seeed Fusion PCB service. They arrived back this week:
Front Panel:
Front close-up - note there is no solder mask between the 0201 resistor pads This will make soldering it just that little bit more difficult. Some of the black silkscreen is out of alignment too, compared with what was ordered - see the green screenshots above:
Battery Backside:
Anyway, I think it looks ok enough for the cost price of 28cents each. I think enough of the BOM parts have arrived for me to have a go at hand soldering up a PCB board tomorrow.
Front Panel:
Front close-up - note there is no solder mask between the 0201 resistor pads This will make soldering it just that little bit more difficult. Some of the black silkscreen is out of alignment too, compared with what was ordered - see the green screenshots above:
Battery Backside:
Anyway, I think it looks ok enough for the cost price of 28cents each. I think enough of the BOM parts have arrived for me to have a go at hand soldering up a PCB board tomorrow.
Re: SMD Soldering Test
After a good nights sleep, I had a go at hand soldering up the board. As it's a pretty small PCB (a bit smaller than a 20c coin), I first soldered a small pad of solder onto each pad, then placed and held the component in place with a set of fine tweezers and tacked down one end. Then properly soldering down the other end, before repeating the first end. This worked ok for the larger (1206, 0805) items, but not that well for the smaller ones. The 0201 was just hit and miss, but I got it after a few goes. I did melt the first 0402 red diode, so you can see a blemish just to the lower right of it as I haven't cleaned up the flux yet.
The 0805 Blue LED is a bit faint, so it will need a lower value resistor.
To complete the board people will need a fine set of tweezers, a loupe (or some sort of magnification) to check the board and a multimeter is handy to test the correct diode orientation.
This has been a fun mini-project.
The 0805 Blue LED is a bit faint, so it will need a lower value resistor.
To complete the board people will need a fine set of tweezers, a loupe (or some sort of magnification) to check the board and a multimeter is handy to test the correct diode orientation.
This has been a fun mini-project.
Re: SMD Soldering Test
well done Paul !
BLOG: https://my.makeraddiction.com/
Thingiverse: https://www.thingiverse.com/seaton/
Github: https://github.com/madeinoz67
Thingiverse: https://www.thingiverse.com/seaton/
Github: https://github.com/madeinoz67
Re: SMD Soldering Test
Morning Paul,
Just a reply to test the email settings..
Just a reply to test the email settings..
Re: SMD Soldering Test
I love the visual display of data and graphs etc, so below is a pie chart of the make up of the project costs. It includes a plastic bag and 30cm of 0.3mm thick solder, but not the CR2025 battery (included at a $0.0 cost), as it's difficult to travel with these kinds of batteries in some countries.
The top two costs are the battery holder at 30.3cents each, and the PCB at 28.3 cents each. With a bit of further hunting, I bet I could reduce some of the component costs quite a bit, but at the moment, I am only buys in quantities of 100.
The top two costs are the battery holder at 30.3cents each, and the PCB at 28.3 cents each. With a bit of further hunting, I bet I could reduce some of the component costs quite a bit, but at the moment, I am only buys in quantities of 100.
Re: SMD Soldering Test
This project should really be called a SMD Soldering Challenge. I recently took a few kits along with me to China and a few people successfully gave it a go. Since then I have experimented with some packaging. The first type had the components glued down. It looks the best, but the glue will leek into some of the LED components and make it difficult to get them out. It also took a long time to glue each of the 20 resistor and LED strips into place.
Someone suggested I give double sided take a go. That technique halved the packaging time, but the tape doesn't hold the components down as strong as the PVA glue does. While the kits BOM cost is quite low, the labour costs are very high and most probably not economically fully recoverable in this format.
I now have 60 odd packets made up for sale at the March 2019 FOSS Asia conference, so it will be interesting to see how well they travel.
Sample Kit - glued (front/back):
Someone suggested I give double sided take a go. That technique halved the packaging time, but the tape doesn't hold the components down as strong as the PVA glue does. While the kits BOM cost is quite low, the labour costs are very high and most probably not economically fully recoverable in this format.
I now have 60 odd packets made up for sale at the March 2019 FOSS Asia conference, so it will be interesting to see how well they travel.
Sample Kit - glued (front/back):