[Darkstar77]

My kit arrived in the mail today. It arrived after its journey from Beezar to Canada intact, and well packed. I am terribly excited, going to start it this weekend.

 

[tomb]

My kit arrived in the mail today. It arrived after its journey from Beezar to Canada intact, and well packed. I am terribly excited, going to start it this weekend.

Glad to hear it!

 

[Darkstar77]

Glad to hear it!

Okay, stupid question for the day. I've done lots of PCB soldering in the past, and somewhat recently in building multi-rotor RC helicopters (the power distribution and controller boards require a lot of soldering to complete). I have never bothered cleaning off the rosin flux residue before, and so far as I can tell I have never had any problems. I know rosin flux is non conductive and non corrosive. Is the thorough cleaning of the board after soldering in the detailed directions for cosmetic reasons, or for functional reasons?

I googled around on this topic for a while last night, and found a lot of conflicting opinion and "fact"; as well as a lot of "how to solder" articles.

 

[Avro_Arrow]

Sometimes residue left over from soldering is conductive/corrosive.
It is better to error on the side of caution when writing instruction
that others will follow. If you KNOW your flux is safe to leave on
then feel free to do so. Otherwise, better safe than sorry...
 

 

[tomb]

  Sometimes residue left over from soldering is conductive/corrosive.
It is better to error on the side of caution when writing instruction
that others will follow. If you KNOW your flux is safe to leave on
then feel free to do so. Otherwise, better safe than sorry...
 

Agreed.
 
It's just me, but I always rinse a PCB of all flux residue.  If nothing else, I absolutely hate the appearance/texture of flux residue after a period of time.  It turns into really nasty stuff and is not something that I would personally like to leave on a project that I built.  When it comes to SMD work in DACs/etc., it becomes even more important to get it clean, IMHO.
 
I'm so particular, I've probably turned proper rinsing of a PCB into a mini-science.  This section on rinsing the Torpedo PCB can give you an idea:
http://www.diyforums.org/Torpedo/TORPEDOconstruct9.php
 
The Torpedo PCB is very much larger than the SSMH PCB, so it probably warranted that kind of documentation.

  You should not have that much of an issue with cleaning the SSMH PCB.  Try to use the 91% alcohol shown in the website page above.  It's ridiculously cheap at Walmart and works better than commercial flux removers, IMHO (and is not dangerous in an un-ventilated environment).  Combine the rinsing (an old toothbrush is recommended) with patting up the dissolved-flux-alcohol mix with paper towels.  If you don't pat up the liquid with each rinse, all you're doing is moving the flux around on the PCB.  When it's dry, if you see white deposits around the solder joints - it hasn't been rinsed enough.  It may take up to a half-dozen rinse actions to get things perfectly clean.

 

[Darkstar77]

Agreed.

It's just me, but I always rinse a PCB of all flux residue.  If nothing else, I absolutely hate the appearance/texture of flux residue after a period of time.  It turns into really nasty stuff and is not something that I would personally like to leave on a project that I built.  When it comes to SMD work in DACs/etc., it becomes even more important to get it clean, IMHO.

I'm so particular, I've probably turned proper rinsing of a PCB into a mini-science.  This section on rinsing the Torpedo PCB can give you an idea:
http://www.diyforums.org/Torpedo/TORPEDOconstruct9.php

The Torpedo PCB is very much larger than the SSMH PCB, so it probably warranted that kind of documentation.   You should not have that much of an issue with cleaning the SSMH PCB.  Try to use the 91% alcohol shown in the website page above.  It's ridiculously cheap at Walmart and works better than commercial flux removers, IMHO (and is not dangerous in an un-ventilated environment).  Combine the rinsing (an old toothbrush is recommended) with patting up the dissolved-flux-alcohol mix with paper towels.  If you don't pat up the liquid with each rinse, all you're doing is moving the flux around on the PCB.  When it's dry, if you see white deposits around the solder joints - it hasn't been rinsed enough.  It may take up to a half-dozen rinse actions to get things perfectly clean.

Thank you for the responses gentlemen. I've never really encountered any whitish buildup in the past, but I do have a small amount after placing the resistors on the SSMH board. Alcohol and a tooth brush sounds like a plan.

 

[nbkgudx]

Hello all,
 
I recently completed my first build. I make sure to pay close attention and follow the guide. When it came time finally power on the amp i noticed two small electrical sparks at the top of the standoff screw on the outside of the case. I decided to let the amp run for about 10 minutes. I then went to turn it off, as I attempted to turn it off a large blue spark quickly shot the moment i flipped the power switch off. This spark was right above the switch. Would this be a grounding or wiring issue? I've attached some photos of the build. 
 
I also made the mistake of soldering the switch wires into the Terminal Blocks because I was not aware that they were screw in design.
http://s27.postimg.org/4ue8g018j/image.jpg
http://s27.postimg.org/k5o1glykj/image.jpg
http://s27.postimg.org/ynl8olpvn/image.jpg
http://s27.postimg.org/9k464ls8z/image.jpg

 

[tomb]

  Hello all,
 
I recently completed my first build. I make sure to pay close attention and follow the guide. When it came time finally power on the amp i noticed two small electrical sparks at the top of the standoff screw on the outside of the case. I decided to let the amp run for about 10 minutes. I then went to turn it off, as I attempted to turn it off a large blue spark quickly shot the moment i flipped the power switch off. This spark was right above the switch. Would this be a grounding or wiring issue? I've attached some photos of the build. 
 
I also made the mistake of soldering the switch wires into the Terminal Blocks because I was not aware that they were screw in design.
http://s27.postimg.org/4ue8g018j/image.jpg
http://s27.postimg.org/k5o1glykj/image.jpg
http://s27.postimg.org/ynl8olpvn/image.jpg
http://s27.postimg.org/9k464ls8z/image.jpg

I don't think I see any shoulder washers on those MOSFETs.  If the tabs come into contact with the screws and case, it will short things out.  It may be an optical illusion, but it also appears that there's stray solder touching between the two connections on the power jack.  That would short things, too.

 

[nbkgudx]

Thanks. You are correct there are no shoulder washers on the mosfets. Do you think I might have permanently damaged the device when I powered it on?

 

[tomb]

  Thanks. You are correct there are no shoulder washers on the mosfets. Do you think I might have permanently damaged the device when I powered it on?

MOSFETs are pretty tough.  I'm more concerned, however, because I read you let it run a while even after you saw the sparks.

 
Still, put the shoulder washers in, double check that power jack, and try it again.  (You might try a DMM to see if you have zero ohms between the MOSFET tabs and ground.)  If it works, then you dodged a bullet.  If not, then you need to replace those MOSFETs.

 

[nbkgudx]

 
MOSFETs are pretty tough.  I'm more concerned, however, because I read you let it run a while even after you saw the sparks.

 
Still, put the shoulder washers in, double check that power jack, and try it again.  (You might try a DMM to see if you have zero ohms between the MOSFET tabs and ground.)  If it works, then you dodged a bullet.  If not, then you need to replace those MOSFETs.

Thanks for the help. I don't understand basic hardware, can you provide me more details on the order in which i should place the washers and rings in relation to the mosfet that is currently resting on the case? 

 

[tomb]

 

 
MOSFETs are pretty tough.  I'm more concerned, however, because I read you let it run a while even after you saw the sparks.

 
Still, put the shoulder washers in, double check that power jack, and try it again.  (You might try a DMM to see if you have zero ohms between the MOSFET tabs and ground.)  If it works, then you dodged a bullet.  If not, then you need to replace those MOSFETs.

Thanks for the help. I don't understand basic hardware, can you provide me more details on the order in which i should place the washers and rings in relation to the mosfet that is currently resting on the case? 

This page on the SSMH website has everything you want to know:
http://www.diyforums.org/SSMH/SSMHheatsink.php

 

[nbkgudx]

 
This page on the SSMH website has everything you want to know:
http://www.diyforums.org/SSMH/SSMHheatsink.php

If i lost the shoulder washer can i use a standard washer? 

 

[UKToecutter]

You really need to use a shoulder washer.
It stops the fixing screw from touching the inside of the hole on the device's tab.

 

[Amatsu]

Just as a curiosity, you can usually find up to 6 mosfets with screws, washers and insulation pad inside computer power supplies. If someone has a dead power supply it can be a good way to recycle some parts. Just be very careful if you're gonna poke inside a power supply, be sure to fully discharge it, I don't recommend opening one if you don't know what you're doing. 
 
I actually did a p2p version of the amp inside the case of a power supply after removing everything, using it's own power switch and cables.