Nuts are driving me nuts! TO-204 Package - Page 1
Forum section: electronics / repair

author: NivagSwerdna
author_rank: Super Contributor
timestamp: February 19, 2021, 08:09:35 pm
content: I'm trying to remove a TO-204 transistor and in the end I gave up trying to disassemble it in place because I couldn't unscrew the nuts!They seem to be between 5 and 6mm in size... Is 5.5mm a standard size?Do you get spanners or box spanners in 5.5mm sizes?Sorry if this is trivial question but this size eludes me!!

author: jpanhalt
author_rank: Super Contributor
timestamp: February 19, 2021, 08:20:29 pm
content: 5.5 mm (0.216") is pretty big for that purpose. Was the that major diameter of the bolt or between faces of the nut?Anyway, there is green thread locker on them. If LocTite, that is one of the stronger versions, but heating (hot air or with a soldering iron) will help. They also appear to have internal toothed lock washers under them. Actually quite typical, except for the ambiguity on size.Rather than a spanner, I would suggest a set of small socket wrenches in a screwdriver handle, aka "nut drivers."Edit: Like this set, but I almost never get HF tools:https://www.harborfreight.com/hollow-shaft-metric-nut-driver-set-7-pc-69238.html?cid=paid_google|||69238&utm_source=google&utm_medium=cpc&utm_campaign=&utm_content=&gclid=EAIaIQobChMIqI7Pt-P27gIVsvLACh1V8wAHEAQYAyABEgK4GPD_BwE

author: Tomorokoshi
author_rank: Super Contributor
timestamp: February 19, 2021, 08:21:56 pm
content: I have 5.5 mm socket drivers. 5.5 mm works out very close to 7/32".

author: rvalente
author_rank: Frequent Contributor
timestamp: February 19, 2021, 08:23:50 pm
content: By the looks of it seems to be imperial,|O not metric.Get a vise pliers, they should do the trick

author: NivagSwerdna
author_rank: Super Contributor
timestamp: February 19, 2021, 08:32:02 pm
content: Actually now I measure it again... maybe somewhere between 5.2mm and 5.4mm between the flat faces... ?It's from a Japanese CRT... I assumed it had to be metric... ?I can brute force it but it would be nice to have the right tool for the job.

author: langwadt
author_rank: Super Contributor
timestamp: February 19, 2021, 09:26:58 pm
content: 5.5mm is the standard size for M3 nuts

author: Monkeh
author_rank: Super Contributor
timestamp: February 19, 2021, 09:28:15 pm
content: 5.5mm is the standard A/F measurement for an M3 nut. Typically slightly undersized, add measurement error and..I have spanners, sockets, and nut-drivers in 5.5mm - pretty hard to work without them.

author: rvalente
author_rank: Frequent Contributor
timestamp: February 19, 2021, 10:35:06 pm
content: If they're DIN 934 then M3 is 5.5mm hexagon..I usually use 6 and can tight them fine.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: February 19, 2021, 10:45:31 pm
content: Thanks all. I have ordered a 5.5mm nut driver... I think it will make my life better.

author: Gregg
author_rank: Super Contributor
timestamp: February 19, 2021, 11:08:44 pm
content: This set of screwdrivers also has both a 5.5M socket and open end spanner:https://www.amazon.com/ORIA-Screwdriver-Precision-Electronics-Smartphone/dp/B07281FT78This set also has the hard S-2 steel bits and a handle with a decent grip

author: Audiorepair
author_rank: Frequent Contributor
timestamp: February 19, 2021, 11:16:03 pm
content: I regularly find a metric nut, usually M3 thread, that doesn't seem to be a metric size.But if I go to my Imperial nut spinners I find the perfect fit.Never made much sense to me.