WOPL 400 1st time build

plex

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#1
Hello all. I just started on this project with my son. He's 15. He assembled all the boards. Let me know what you guys think. How does it look? I also took videos, I'll try to put it on YT.
 

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George S.

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#2
Looking good so far. Get the flux off the boards using isopropyl alcohol and a tooth brush or acid brush. Get the extra solder off the top of the PEM nuts on the backplanes. Then closely inspect all solder joints with some sort of available magnification, particularly the bottom right backside of the control board. I see a suspect area in the photo, but hard to tell for sure on phone.
It's fantastic that a youngster has interest in a project this.
 

gene french

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#4
Hello all. I just started on this project with my son. He's 15. He assembled all the boards. Let me know what you guys think. How does it look? I also took videos, I'll try to put it on YT.
good luck....you are in good hands here....take it from the voice of experience....lol
 

gene french

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#7
Hello all. I just started on this project with my son. He's 15. He assembled all the boards. Let me know what you guys think. How does it look? I also took videos, I'll try to put it on YT.
keep coming with the pics on the build...many guys here will critique your work and look for mistakes....they worked diligently with me to produce an uneventful power up of my new wopl 400....now into my third day of listening pleasure...
 

Gepetto

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#9
Hello all. I just started on this project with my son. He's 15. He assembled all the boards. Let me know what you guys think. How does it look? I also took videos, I'll try to put it on YT.
The biggest thing I see on this build that needs addressing is the solder on TOP of the PEM nuts. That will prevent the board from sitting flat on the nylon shoulder washers which is essential. Clean that up with Soder WIck before proceeding much further...it looks like your son is doing fine for his age.

Did you remove the orange caps that come on top of the PEMs before soldering? The job of those is to keep the solder off the tops in addition to providing a vacuum surface for pick and place SMT machines. They are high temp Kynar shields and easily withstand the heat of soldering.
 

gene french

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#10
The biggest thing I see on this build that needs addressing is the solder on TOP of the PEM nuts. That will prevent the board from sitting flat on the nylon shoulder washers which is essential. Clean that up with Soder WIck before proceeding much further...it looks like your son is doing fine for his age.

Did you remove the orange caps that come on top of the PEMs before soldering? The job of those is to keep the solder off the tops in addition to providing a vacuum surface for pick and place SMT machines. They are high temp Kynar shields and easily withstand the heat of soldering.
glad to see you survived your vacation....
good to have you back...
 

plex

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#11
The biggest thing I see on this build that needs addressing is the solder on TOP of the PEM nuts. That will prevent the board from sitting flat on the nylon shoulder washers which is essential. Clean that up with Soder WIck before proceeding much further...it looks like your son is doing fine for his age.

Did you remove the orange caps that come on top of the PEMs before soldering? The job of those is to keep the solder off the tops in addition to providing a vacuum surface for pick and place SMT machines. They are high temp Kynar shields and easily withstand the heat of soldering.
Yes I will use the soder wick to clean that up thanks and yes the orange caps were removed before by mistake. He overlooked that part in the instructions. :eek:
 

mlucitt

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#15
The biggest thing I see on this build that needs addressing is the solder on TOP of the PEM nuts.
I always clamp my backplane boards in the Bridgeport and take a skim cut on the PEM nuts with a fly cutter to make sure I get all the solder that runs under the Kevlar shields. A quick stroke with the 8" mill file across the PEM nuts and they are good to go.

Not really, but I dream about stuff like this...
Oh, and I have used a small flat file to clean up some little traces of solder on top of the PEM nuts. It happens...
 

J!m

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#18
I don’t think you need 2000 for polishing aluminum. You can probably stop at 1000 and use compound from there due to softness. Hard steel might go to 1500 but cold rolled can probably get a shine from 1000.

If you are flattening, you should not use finer than 400 as it won’t take the high spots off finer; just glides along the existing surface.
 

Mohawk

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#19
The belt sander or mill is WAY overkill for taking off some stray solder.... imo

A small flat file or just wrap a sheet of light grit sandpaper around a chunk of flat wood like a piece of an old square table leg...

Then clean, clean and clean again !
 

George S.

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#20
I just glide a small fine cut file over the little bit of solder I invariably get on the top shoulder of the PEM nuts. Cuts it right off as it's so soft.
If I was to use solder wick I'd probably fire up the Weller Expert pistol grip gun and get it off quick without heating the whole nut.
I know proper way is to leave those amber Kynar shields on, but I like to spin the nuts in the holes so I get good even heating and solder penetration with a doughnut on the back side. Easier for me if the caps are off.
Have to admit I slightly over did it on the 700 backplanes. Once the parts are up to temp and that nuts floating on liquid solder it's easy to spin it and get even heating and penetration. Never had a issue with nut alignment on two 400s and the 700.
 

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