Removing a display (intact) from a Datron 1071 - Page 1
Forum section: electronics / testgear

author: acts238willy
author_rank: Regular Contributor
timestamp: March 07, 2018, 06:16:07 pm
content: Need help figuring out how to desolder that row of pinson the top of the display... I've tried... (pic)solder wickHakko suction toolhot iron with air pressureNothing works. There must be a big heat sink/ RF noiseshield that's removing the heat.The Hakko does just fine on the shiny soldered jointson the other boards. (pic)Is this going to end up being a saw and Dremel tool nightmare?

author: 4thDoctorWhoFan
author_rank: Regular Contributor
timestamp: March 07, 2018, 06:21:47 pm
content: The Hakko 808 should do the job.Make sure you have the temperature control turned up and are using the correct size nozzle.

author: TheSteve
author_rank: Unknown
timestamp: March 07, 2018, 06:29:08 pm
content: Prewarming the board will also be a big help - hot plate, heat gun etc(don't get carried away).

author: acts238willy
author_rank: Regular Contributor
timestamp: March 07, 2018, 08:42:59 pm
content: There are 3 nozzles... 0.8, 1.0 and 1.6.The 1.6 was the one I was using and itcompletely sucked the solder out of thenormal pin-in-hole locations. The wireswould move easily with a nudge after theremoval and the solder left was like a thinplating.The display terminal solder hardly meltedand several terminals had the copper liftand stick to the Hakko. I had the adjustmentfor heat turned clockwise all the way to theright. Like I said, it instantly melted the shinysolder on the circuit boards and sucked themclean.Perhaps the 1.0 nozzle? Don't want too muchheat going down the leads to the glass sandwich!!!

author: acts238willy
author_rank: Regular Contributor
timestamp: March 07, 2018, 08:44:53 pm
content: I do have a temp controlled heat gun...What temp is not too hot for the pins?Don't want to destroy the display!

author: PaulAm
author_rank: Frequent Contributor
timestamp: March 07, 2018, 08:58:10 pm
content: You may want to add some low melting point alloy solder to help that flow at a lower temperature. If you want to save the board, it'd be worth it.

author: floobydust
author_rank: Super Contributor
timestamp: March 07, 2018, 08:59:57 pm
content: Use a soldering iron to heat up the display pins on the display side, while(at the same time)vacuum-desoldering on the other side of the PCB.It's a two-handed operation. It works great for high heat with the Kovar leads.So the PCB is vertical, and using both hands, soldering iron in one and vacuum-desoldering wand in the other hand, you heat up the lead on both sides and desolder.edit: less vague

author: splin
author_rank: Frequent Contributor
timestamp: March 07, 2018, 10:43:16 pm
content: Feedbackloop removed one in this video starting at 2:30He posts here, or at least he used to, so perhaps you could ask him directly if you need more advice.

author: acts238willy
author_rank: Regular Contributor
timestamp: March 08, 2018, 07:14:54 am
content: I watched part 1... 3/4 hour.Murphy's law - the thing I wantedto see was in part 2!Still doesn't show the removal in process.I'll try to message him tomorrow.

author: acts238willy
author_rank: Regular Contributor
timestamp: March 09, 2018, 06:44:08 am
content: Went to 350C with the heat gun, full temp on theHakko solder sucker...NUTIN'So, it's razor saw and Dremel time... got the first 2pins loose, the thru-holes came right off with justa touch of a 325C soldering iron. The pin in themiddle was one of the non-soldered ones...About 8 or 9 hours to go.

author: acts238willy
author_rank: Regular Contributor
timestamp: March 09, 2018, 06:45:33 am
content: Feedbackloop is nowhere to be found...

author: acts238willy
author_rank: Regular Contributor
timestamp: March 10, 2018, 03:58:49 am
content: Finally got it loose...