Clean fasteners without damaging protective plating?

[WildCoast]

Almost always when working on vehicles you need to clean the threads of an old fastener, especially if you're re-applying loctite.

Using a bench grinder with a steel wire wheel works real good but the steel very quickly strips off the protective zinc or nickle plating on the fastener - the bolt looks clean and nice but not for long! Without the plating the raw steel will corrode super quickly, so you've actually done more harm than good.

Any advice on how to clean fasteners without damaging the protective coating? I've been using a brass wire brush, but not sure if that's ideal. Brass is technically a mix of zinc and copper, and copper is super soft, so I'm assuming it would be softer vs the electroplated zinc or nickle coating and won't damage it while still removing dried old loctite, rust, etc?

I know you can get a full on zinc plating set up to refresh the protective coating and there are youtube vids showing how to do that, but there is a ton of prep involved and would be far far too time consuming for general vehicle work! I'm not restoring an antique to shiny ocd perfection, I just want to avoid doing damage to high quality OEM plated fasteners while doing general work.

 

[atikovi]

Any thread lock or anti-seize you put on the threads will prevent future corrosion. My bench grinder wheel is not steel so I don't worry about it.

 

[tnt_motorsports]

I never wire wheel a bolt. Sometimes I wire brush or nylon brush a bolt, but usually I just spray them with brake cleaner and then add the anti-seize or thread locker and put them back in.

Just my $0.02

 

[Dave9]

Depends... if it's really bad and I can (and not cost prohibitive for the situation), I just get a new bolt.

I don't encounter many that are nickel or zinc coated, usually black oxide, or a few (and moreso in aftermarket) zinc chromate... okay that's zinc but I think of it as chromate since there's also the dull grey, soft zinc coating you'd find on certain bolts like on fences.

Otherwise, sometimes I'll use phosphoric acid and a toothbrush (and wear gloves!) to get rust off, but this embrittles the surface a bit, so not good for very fine threads. With old threadlock, sometimes I'll just run the bolt through a die (from a tap & die set) if I have that size. Wire wheel... I've done that a few times on very coarse pitched bolts, and more often to clean up the bolt head itself, but more often it is not convenient to stop what I'm going and go over to the bench grinder so I'd just touch up the bolt head faces with a file instead, just make them true, not make them 100% rust free.

You're not restoring an antique so I don't see the issue. Are these bolts you plan to have to take off and put back on, often? If not, might it be a case where the work you did, may not need redone for a very long time if ever again during the life of the vehicle, so it's not those bolts you have to worry about in the future but rather, the others that have not ever come off since the factory?

As someone already mentioned, you can use threadlock if you feel it's important for that reason, rather than that the application calls for it, then reduce the torque value used a little bit. I'll sometimes coat the head of bolts with silicone brake paste.

If it's not an antique, I don't feel like it is all that important to preserve the OEM fasteners, that while they are usually fair quality, it is not as though you can't find "almost" any standard sized bolt/nut/etc in good quality to replace it, without even leaving your home. The internet is wonderful. It helps to own calipers.

 

[WildCoast]

My bench grinder wheel is not steel so I don't worry about it.

Curious what you use instead? Nylon abrasive brushes?

 

[WildCoast]

Sometimes I wire brush or nylon brush a bolt

Do you use a nylon bristle brush on the bench grinder? Looks like Nyalox and a few other brands make nylon abrasive brushes (nylon bristles with aluminum oxide friction impregnation). I'm guessing if I use the finer (240 or 120 grit) then it would clean up bolts nicely and not damage the plating... also seems cheaper vs true brass wire brushes!

 

[97prizm]

I never wire wheel a bolt. Sometimes I wire brush or nylon brush a bolt, but usually I just spray them with brake cleaner and then add the anti-seize or thread locker and put them back in.

Just my $0.02

Nylon brush or if you want a blowtorch will melt the old thread locker off.

 

[atikovi]

Curious what you use instead? Nylon abrasive brushes?

I think it's brass, or it looks like it.

 

[tnt_motorsports]

Do you use a nylon bristle brush on the bench grinder? Looks like Nyalox and a few other brands make nylon abrasive brushes (nylon bristles with aluminum oxide friction impregnation). I'm guessing if I use the finer (240 or 120 grit) then it would clean up bolts nicely and not damage the plating... also seems cheaper vs true brass wire brushes!

Just a hand held nylon brush.

Just my $0.02

 

[WildCoast]

Just a hand held nylon brush.

Just my $0.02

That's what I've been doing but it takes forever if you're doing a big job and literally hand brushing 50 fasteners... have a bench grinder sitting there which would take seconds, so trying to figure out how to speed up my workflow

 

[tnt_motorsports]

That's what I've been doing but it takes forever if you're doing a big job and literally hand brushing 50 fasteners... have a bench grinder sitting there which would take seconds, so trying to figure out how to speed up my workflow

A strainer in a bucket of purple power or super clean might be better.

Just my $0.02

 

[xmanjeff]

just screw them back in the hole and move on to the next problem in life

 

[MSCH]

run em thru on a tap or die

 

[KrisZ]

If you’re that anal, get new fasteners. Otherwise the threads don’t need to be like brand new again. A wire brush done by hand will suffice in most cases and will not remove any plating.

 

[TurboTravis]

Evaporust

 

[64bawagon]

The plating that I encounter these days doesnt do much more than keeping the parts shiny on the showroom floor. Once they enter the cold cruel world they are of little value.
I worked for a major fastener distributor in the late 70's. We had a local place that did plating (long gone) and their yellow zinc dichromate plating really stood up. I dont think it helped the planet much though.

 

[goingplacesanddoingstuff]

Almost always when working on vehicles you need to clean the threads of an old fastener, especially if you're re-applying loctite.

Using a bench grinder with a steel wire wheel works real good but the steel very quickly strips off the protective zinc or nickle plating on the fastener - the bolt looks clean and nice but not for long! Without the plating the raw steel will corrode super quickly, so you've actually done more harm than good.

Any advice on how to clean fasteners without damaging the protective coating? I've been using a brass wire brush, but not sure if that's ideal. Brass is technically a mix of zinc and copper, and copper is super soft, so I'm assuming it would be softer vs the electroplated zinc or nickle coating and won't damage it while still removing dried old loctite, rust, etc?

I know you can get a full on zinc plating set up to refresh the protective coating and there are youtube vids showing how to do that, but there is a ton of prep involved and would be far far too time consuming for general vehicle work! I'm not restoring an antique to shiny ocd perfection, I just want to avoid doing damage to high quality OEM plated fasteners while doing general work.

Water and dish detergent work pretty well for this kind of thing, followed by paper towels. Don’t overthink it.

 

[Astro14]

I run most fasteners under the wire wheel for a bit - if they’re going back in, I want clean threads. A dab of Loctite or antisieze will keep them from corroding. If they get neither, then I hit them with a shot of Rustoleum paint, either black or pure zinc primer. I want a clean feel for torque and a bolt that I can disassemble again in the future.

Overly meticulous?

Yep. But I work on my cars, at my pace, and don’t have hard deadlines or waiting customers, well, except for Mrs. Astro, who has her choice of two cars, and is welcome to drive one of mine if she chooses.

My wire wheel setup is much more sophisticated than it once was. Bigger grinder. Dust collection.

Front view in the new tool thread, linked, but shown here with the shop vac hookup. I used heat resistant silicone ducting, because metal bits coming off a grinding wheel can be hot.

Post in thread 'New tool thread'
https://bobistheoilguy.com/forums/threads/new-tool-thread.328515/post-6559275

 

[Soft Cars]

NAPA 7771048

I clamp the bolt head in the jaws of locking pliers and clean the threads manually with a wire brush.

I'm very meticulous about fastener threads.