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cleaning paint off threads
peter030371 - 25/2/14 at 08:01 PM

So my car is slowly coming together but I am a little stuck on my Striker the lower front wishbones have a large threaded hole for a metro ball joint. This thread has very helpfully been powder coated...how do I clean the thread?

Not got it in front of me but its circa 35mm thread so I don't have a tap in my set that big

Does a magic tool I have never seen exist?

theprisioner - 25/2/14 at 08:19 PM

If it is a male thread use a Thread file typical example: ebay:181332259968

gremlin1234 - 25/2/14 at 08:20 PM

quote:
Does a magic tool I have never seen exist?
make one

for cleaning a thread, any old bolt/fitting with a saw cut or angle grind, should work.

similarly, a nut with cut through it will clean an external thread.

now ask why did I throw out that decrepit old metro ball joint...

gremlin1234 - 25/2/14 at 08:20 PM

quote:
Does a magic tool I have never seen exist?
make one

for cleaning a thread, any old bolt/fitting with a saw cut or angle grind, should work.

similarly, a nut with cut through it will clean an external thread.

now ask why did I throw out that decrepit old metro ball joint...

rusty nuts - 25/2/14 at 08:44 PM

If you have an old ball joint just file a flat or two on the threads before screwing it into the threads to clean them . Failing that use a small rotary wire brush in a die grinder or Dremel type tool,finish off using a new ball joint

nick205 - 25/2/14 at 10:16 PM

Assuming you need to clean a female thread (you mentioned not having a tap), then I would run a scalpel vertically around the thread to take the powder coat of to tops of the thread. Once you've broken through, then use a sharp scribe to run carefully around the bottoms of the thread. The powder coat should come out relatively easily.

Madinventions - 25/2/14 at 11:21 PM

I used a blob of Nitromors on a cotton bud for mine. I just waited for it to do it's thing then cleaned it out with a combination of cloths and brushes. Probably the least chance of any damage to the threads doing it like this?

loggyboy - 26/2/14 at 01:27 AM

Use a sharp knife to cut around the rim of the thread, then scrape a small amount away from the first thread or 2, enough to get a bolt to bite. Spray with wd40 and tighten and loosen bolt till it removes any powder coat. The cut edge will reduce chance of powdercoat cracking away from the thread hole.
If coating is really thick and deep in the hole, and you have a spare bolt you could try hack sawing a small cut against the thread direction to get it to bite into the coating. Turn it back and forth as if using a tap.

ashg - 26/2/14 at 06:01 AM

one of these on the end of a drill or buy the correct tap if you want to do a really good job

http://www.toolstation.com/shop/Power%20Tool%20Accessories/Wire%20Abrasives/Decarb%20Wire%20Brush%20Set/d80/sd1920/p53351


peter030371 - 26/2/14 at 09:26 AM

Thanks for all the suggestions, lots of good ideas for me to work through

40inches - 26/2/14 at 09:53 AM

quote:
Originally posted by Madinventions
I used a blob of Nitromors on a cotton bud for mine. I just waited for it to do it's thing then cleaned it out with a combination of cloths and brushes. Probably the least chance of any damage to the threads doing it like this?


This is what I would do, a 35mm dia hole gives plenty of working space. Wonder how much a tap would cost