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Hi, can anyone recommend the best temperature to set a desoldering iron at for removing components from classic series logic boards ? I am finding that I need 400 Celcius but that sounds a little high to me.

Thanks
John

Never needed more than 310 C. Perhaps you're just out of calibration?

The Classics were manufactured with tin-lead solder alloys (way before the age of lead-free soldering!) which have a low melting point. Start with lower temperatures first, like 290 or 300C which should be OK. Be very careful, as the 5-digit LED displays are VERY sensitive to heat!

I hope this helps,

Joel Setton

I typically use about 600-650F (315-340C) when soldering, which is probably higher than needed. I highly recommend a desoldering gun such as a Hakko 880 when desoldering the chips. The heat is applied only for about 2 seconds each connection and it's clean enough to fall right out.

F to C conversion thanks to my handy HP-55. Now if I could just find some use for the timer. ;)

Quote:
F to C conversion thanks to my handy HP-55.

Interesting. I hadn't realized unit conversions (English-Metric, that is) had been built in to calculators that early. Looking at the HP-55 features, I was surprised to learn that it included BTU-Joules and LBF-Newtons, whereas most calcs lesser than say, the 28 series, limit themselves to length, mass, volume, and temperature, and only one of each of the aforementioned.

Quote:

Interesting. I hadn't realized unit conversions (English-Metric, that is) had been built in to calculators that early. Looking at the HP-55 features, I was surprised to learn that it included BTU-Joules and LBF-Newtons, whereas most calcs lesser than say, the 28 series, limit themselves to length, mass, volume, and temperature, and only one of each of the aforementioned.


The HP-45 also had a few conversions: cm/in, kg/lb, ltr/gal. But in this case it offered the conversion factors only, one still had to multiply or divide appropriately. The 55 did the math at the push of the button.

Thanks for the feedback all !! Might be a calibration issue.

Dan, my Hakko 808 "chinese clone" has a minimum temp of 350, but I think the Hakko has a minimum of 380 - is that what you use ?

Thanks
John

Hi John,

Ah! Now I know who you are - wasn't paying attention.

Anyway I am using whatever the default is from the factory. I haven't tried to measure it.

-- Dan