Repair of $150k Phantom Flex 4k camera - advanced soldering

[rx8pilot]

This project saw some success today! I will say it was the most anxious I have ever been soldering anything. The cost of failure was rather extreme by my standards.

In the end, I elected to design and machine two special fixtures that would hold the PCB, provide thermal protection for the existing connectors, and provide a way to apply heat safely. Certainly the first time I have ever machined parts to solder a single connector. Lots of consideration and half a day at the CNC - it was game time.

I put all the parts in the convection batch oven and pre-heated at 100C for about an hour followed by 150C for 5min and 200C for 3min. At that point, I transferred the fixture to the bench where I had a special holder ready and 2 hot-air systems. One hot air was setup to heat from the bottom of the PCB, the other was handheld and focused on the work area. All was being watched with a microscope so I could see the moment the solder melted. Lots and lots of tacky flux was pumped in and I kept some motion on the hot air nozzle to avoid melting the connector.

Initially, I was planning to remove the connector, clean the pad/pins, stencil paste, and re-flow. Once the original solder flowed, I decided not to remove the connector and see how it looked. With all the flux, the solder wicked nicely on the connector pins leaving a nice fillet and a shiny finish. At that point, I decided not to remove it and examine the result more closely. After a clean-up and examination under the microscope - all pins flowed and looked great.

The fixture protected all the other connectors well and the end result looks like a brand new board. What a challenge. It was fun.

[Psi]

Out of interest, are you trying to fix for someone else or do you get to keep it

[rx8pilot]

I definitely do not get to keep it. The owner is paying for the effort so once it is back together and tested, it will go away. I should say that even after this part was repaired, the project is not out of the woods yet. The re-assembly is rather delicate with the image sensor being particularly so. I would estimate that the sensor PCB is worth $60-$80k or so.

Gotta be careful.

Typet purly on my fone.

[rx8pilot]

The camera is back together and appears to be working. Lots of tests need to be done, but this is solid progress.

[Bobertsawesome]

I would be shitting myself having to work on that thing being the cost. Good job on getting it running.

[rx8pilot]

I would be shitting myself having to work on that thing being the cost.

I am not saying that did not happen.........

[Psi]

I hope you billed them a sizable amount. The repair cost should carry a premium for something so expensive, even if the actual repair process wasn't that hard.

Lots of extra care and attention had to be taken and extra stress etc..

[Dubbie]

Nice work rx8!

Love to see some custom made tooling!

[Mr. Scram]

I hope you billed them a sizable amount. The repair cost should carry a premium for something so expensive, even if the actual repair process wasn't that hard.

Lots of extra care and attention had to be taken and extra stress etc..

Except that it was hard. Milling custom brackets on a CNC machine that you happened to have into your garage isn't everyday fare. Lots of high dollar investments and a highly varied skill set are required.

[rx8pilot]

I hope you billed them a sizable amount. The repair cost should carry a premium for something so expensive, even if the actual repair process wasn't that hard.

Lots of extra care and attention had to be taken and extra stress etc..

The agreement was fair, I think. Essentially I based the fee off of a bench technician and machine shop rate to cover the time and materials needed to attempt the repair. If the repair was not possible, that would be all I charge. If I fixed it, however, the rate tripled to cover the value of having a unique setup and skillset to make this happen.

That arrangement was great for me and the owner of the camera.

[Psi]

I hope you billed them a sizable amount. The repair cost should carry a premium for something so expensive, even if the actual repair process wasn't that hard.

Lots of extra care and attention had to be taken and extra stress etc..

Except that it was hard. Milling custom brackets on a CNC machine that you happened to have into your garage isn't everyday fare. Lots of high dollar investments and a highly varied skill set are required.

It sounded a lot more like a very careful and time consuming repair job than a hard repair job.

[rx8pilot]

It sounded a lot more like a very careful and time consuming repair job than a hard repair job.

Yes, exactly. It was all physical/visible failures so diagnostics were not a challenge. Just look through a microscope and that is it. This was all about being slow and methodical in the process of figuring out how to repair it.

The previous Phantoms I have worked on needed component level diagnostics and repairs. SDI drivers/receivers and numerous components related to power management and PDN.

[TiN]

Thanks to you and to owner for sharing the story. 

[rx8pilot]

Thanks to you and to owner for sharing the story. 

I recorded video of most everything and trying to cut a YouTube video for those that are curious how it all went.

[richnormand]

Excellent work there, interesting post indeed.

I have come across similar issues with bad geometries for the soldering iron or using hot air pencils that could damage other stuff around.

I rigged my stereo microscope with a micrometer x-y stage and z adjust to get a stable fix on the area. I keep around an old Pace SensaTemp PS90 soldering iron for these jobs.
This uses solid 1/8" diag (or so) tips that are held with a side set-screw. It is then easy to machine a soldering tip out of a solid copper rod with all the right bends, size, diameter and curves to reach the area to be repaired.
Flux and pre-tin the resultant tip, check temperature and apply to spot to be done. Used aluminium foils with one adhesive side and kapton tape on surrounding devices.

I have done this 8 or 9 times over the years with very good success and no collateral damage on LN2 IR detectors, EDX and microwave stuff.

[cgroen]

Thanks to you and to owner for sharing the story. 

I recorded video of most everything and trying to cut a YouTube video for those that are curious how it all went.

Nice! I'm often checking your channel for new stuff, will be looking forward to some more great stuff from your workshop!