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endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

Any body know of some way of "rust proofing" bolt heads after cleaning them? Seems like some bolts just don't take kindly to wire brushing and want to rust. Is there some sort of home plating method I can use? Not really concerned with the color but I hate it when they rust!

Todd
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'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

!tom · Posted: Fri Apr 06, 2007 2:57 am Post subject:

Paint.
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78 924 NA
5-lug

Dagwood928 · Joined: 22 Nov 2003 Posts: 65

Eastwood has a cheap zinc plating kit that looks good. I'm with you though, I hate rusty bolts!
Darren

Smoothie · Posted: Fri Apr 06, 2007 3:24 am Post subject:

Eastwoods' electroplating and spray "plating" stuff -
http://eastwood.resultspage.com/search?p=Q&ts=custom&w=plating&submit.x=21&submit.y=9

PPG and other manufacturers make metal treatment chems that you can apply either by dipping or brushing. These leave a zinc phosphate coating, but are meant to be primed and painted over. Maybe something like that with a zinc paint used over top - but some of the paint will come off when you tighten the bolts.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

I do the paint thing now but as mentioned it usually chipps off in service making things kinda ugly. May try the PPG zinc phosphate coating. The zinc kit from Eastwood looks good but a little costly. I may have to go that rout though.

Todd
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'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

Replace them with stainless!

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1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet

Smoothie · Posted: Fri Apr 06, 2007 5:40 am Post subject:

<click for pic>
PPG would have you using the first 2 there - DX579 metal cleaner and DX520 metal conditioner. The DX503 is for aluminum. They were in the range of $12-$16 per quart bottle as I recall.

http://www.ppg.com/refinishftpsite/docs/P-226_DX_Metal_Treatment.pdf

-But they really mean for the treated surface to be topcoated. I'd expect the zinc phosphate coating to go longer than bare metal without rusting of course, but I suspect you'll still get rust sooner than you'd like.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Smoothie · Posted: Fri Apr 06, 2007 5:47 am Post subject:

Actually, I have that stuff here already. I could run a little homemade corrosion test on a scrap piece of sheet metal and some bolts.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

Ya, stainless. I just love paying $2.00 a piece for stuff in those little drawers at the hardware store

Smoothie, that would be great if you could plate up half of something and let it sit out under that wonderful NJ sky for a few weeks! Would be a great experiment if you woudn't mind.

Todd
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'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

Smoothie · Posted: Fri Apr 06, 2007 7:55 am Post subject:

Well I'm south-west of the main industrial areas with the refineries etc., so don't get much of that unless the wind blows the wrong way. -But there's enough happening west of us to put some acid in the rain. You show-off with your clear "big sky" and all...

But seriously, yeah I'm most of the way through setting it up already. Will apply several different rust treatments to sheet metal and bolt heads, then hang it in a tree for a while - might even get some squirrel pee on it.

_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Smoothie · Posted: Fri Apr 06, 2007 11:08 am Post subject:

Here's the beginning of the "great experiment" (4 pics) -
http://pg.photos.yahoo.com/ph/smoothies931pics/detail?.dir=/34d0&.dnm=750ascd.jpg&.src=ph

In the fourth pic - http://pg.photos.yahoo.com/ph/smoothies931pics/detail?.dir=/34d0&.dnm=63bcscd.jpg&.src=ph
, the upper bolt head (in the second hole) goes with the upper sheet metal section and was treated with Oxi-Solv. Likewise the lower bolt head (in the fourth hole) goes with the middle sheet metal section and was treated with the un-named rust converter/metal prep (un-named because the label from that bottle is long gone).
You can see a few spots of dull grey on those bolt heads - thats zinc plating that didn't come off while sanding, but was invisible until the metal treatments were applied.
The Dupli-Color Rust Fix spray at bottom goes on clear, then turns black, but it seems it's only the paint (a lacquer) that turns black. -But you wouldn't be interested in that anyway for use on bolts because it comes off too easily.

The contraption's hanging in a tree in the backyard now. I'll start spritzing it with water tomorrow to move the process along.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

20v924 · Joined: 24 Jan 2007 Posts: 205 Location: Phoenix,AZ

If you wire wheel all the stuff you want to plate, you can have a bucket-load of stuff done at your local plater for really cheap. the coatings sound temporary from a can or spray.
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A person is smart. People are stupid

endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

Hey, this is great!! I like the looks of the Oxi-solve and rust converter. They look to be more of a "treatment" rather than a "coating" like paint. Hope one or both work out. Thanks for the effort on this and keep us posted.

Todd
_________________
'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

Smoothie · Posted: Fri Apr 06, 2007 3:16 pm Post subject:

No prob., I'm curious myself because my whole car got treated with the PPG DX579 and DX520 before painting.
Actually, I'm gonna guess that that DX579-DX520 treatment does best. It's the grey-looking section at the bottom of this one -
http://pg.photos.yahoo.com/ph/smoothies931pics/detail?.dir=/34d0&.dnm=e4ccscd.jpg&.src=ph
I'm also going to grind clean a section and apply the DX520 by itself to see if it's really necessary to use DX579 beforehand.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Smoothie · Posted: Sat Apr 07, 2007 11:48 am Post subject:

Hey, who wants to see me make a bolt an Alka-Seltzer? -
http://pg.photos.yahoo.com/ph/smoothies931pics/detail?.dir=/34d0&.dnm=e016scd.jpg&.src=ph

The test piece developed no visible rust from hanging in the tree overnight - no rain obviously.. It didn't even collect any condensation.

Here I ground clean a new section at left and treated it with DX520 alone -
http://pg.photos.yahoo.com/ph/smoothies931pics/detail?.dir=/34d0&.dnm=7aacscd.jpg&.src=ph
After spritzing with water, it along with the top two right side sections developed some rust. That's the bare metal at top and DX579 alone at middle. The only section that hasn't shown rust yet is the DX579+DX520 treated section at bottom-right. That slotted bolt, second from right at bottom is the one that got the dunk treatment in both DX579 and DX520.

On the flip-side at top we have the OxiSolv showing some rust, and the no-name section below it looks a bit worse -
http://pg.photos.yahoo.com/ph/smoothies931pics/detail?.dir=/34d0&.dnm=f457scd.jpg&.src=ph
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox