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Manufacturing & Assembly / Re: Advice on adding missing parts to an assembled board
« Last post by SMTech on Today at 08:51:39 am »Building SMT in two passes on the same side with a reflow in between isn't really a thing done at any serious level. As you note, getting paste on is a problem and also a pick & place has no concept of avoiding collision with already placed parts.
Mini rework stencils and templates are a thing, but they are not the solution for you, you could try fiddling with syringes but its much harder than you might think, and might not work at QFN scale such as that PD chip. ?You choices include:
Change your design so that it more closely fits JLC parts library surely they have a USB PD chip in there somewhere.
Carry on as you are.
Sub contract the assembly to someone in the UK who sources all the parts for you - someone like @Jackster or.. me (other choices exist). This frees up your time for testing and validation & revisions instead of fiddly rework level assembly.
Find that PD chip as a pre assembled module - it probably exists.
You can play with small placers, but this is something you should only do because you really want to get into that side of things and at some level want that toy. Feeders are the most expensive part of an SMT setup, most places will have spent considerably more money on their feeder stock than the placer itself. In small volumes you will frequently find yourself supplied with parts that a pick 'n place can't handle without a custom tray or some chip straightening or other process first.
Mini rework stencils and templates are a thing, but they are not the solution for you, you could try fiddling with syringes but its much harder than you might think, and might not work at QFN scale such as that PD chip. ?You choices include:
Change your design so that it more closely fits JLC parts library surely they have a USB PD chip in there somewhere.
Carry on as you are.
Sub contract the assembly to someone in the UK who sources all the parts for you - someone like @Jackster or.. me (other choices exist). This frees up your time for testing and validation & revisions instead of fiddly rework level assembly.
Find that PD chip as a pre assembled module - it probably exists.
You can play with small placers, but this is something you should only do because you really want to get into that side of things and at some level want that toy. Feeders are the most expensive part of an SMT setup, most places will have spent considerably more money on their feeder stock than the placer itself. In small volumes you will frequently find yourself supplied with parts that a pick 'n place can't handle without a custom tray or some chip straightening or other process first.