Nuts and bolts Restoration

[Daniel H.]

Hi,
I am trying to reuse the bolts on the supension of my 1975. The NCRS judging book calls out for them to be a natural finish. What does that mean? Does it mean they have no Zinc/ phosphate at all on them? My other book (not NCRS book) calls out that they are gray phosphate. What is the right way to restore them?

Regards,
Danny

[Daniel H.]

Re: Nuts and bolts Restoration

The bolts are from the upper and lower A-arm assembly. If the NCRS is callimg them to be natual,can i just wire wheel them and protect them with a flat clear?

[Michael G.]

Re: Nuts and bolts Restoration

By 1975, very, very few GM fasteners were "natural" steel. Most bolts were phosphate and oil or zinc organic coated. Both of these finishes are grainy in appearance, coated with oil, and dark grey to black in color.

The clamp-load delivered by these parts on suspension components is extremely important; the proper finish affects this clamp-load significantly. Plain steel performs much differently than these other finishes, so, before you change anything to plain steel on a critical bolt, I'd verify the actual finish that was used on that particular bolt.

[Dennis O.]

Re: Nuts and bolts Restoration

I used to wire wheel bolts and other small parts. After several close calls with randomly launched missles and more than a few hours looking for small parts on the other side of the shop, I gave in and purchased a vibratory tumbler to clean up these sorts of things. I generally use the pyramid-shaped plastic media, and after several hours in the unit, things clean up nicely. It's also easier on the parts, not to mention your safety glasses. The first one I bought was from Eastwood. It didn't work out of the box, so I sent it back. I then went to Amazon.com, who had a much larger selection (including the Eastwood for less than it sold for from Eastwood itself). I ordered the one that looked best to me and had good reviews. I have been very satisfied with it. You can use a variety of media with it, from iron shot to walnut shells You can get just about any media you want from places like Grainger, etc. The only thing I would do different is buy a larger one so I could do more and larger parts. The one I have is (I believe) 2 quarts; about 10" in diameter and 6" high. Also, if I were going to be using different media types, I would purchase one where extra "bowls" are available and easily changed.

[Alan D.]

Re: Nuts and bolts Restoration

Know that "randomly launched missles" feeling only two well, still looking for one nut.
Word of caution, do not use an acid to clean any harden bolts - the word is the hardness will change.
(I've become convinced that such does happen) Even if that's wrong why take the chance?
The vibratory tumbler sounds like a nice setup, wish I had gotten one earlier.

[Mike E.]

Re: Nuts and bolts Restoration

I've media blasted bolts then used Eastwood Metal Blacking then treated with Boeshield for black phosphate.

For Zinc plate I used their Zinc/Tin Electroplating system. The plate nut in the last photo is just media blasted then treated with Boeshield, the '65 JM calls for it to be natural finish.

Here are a few before and after shots of the same part.









Mike

[Michael G.]

Re: Nuts and bolts Restoration

Alan, actually, the hardness won't change due to an acid cleaning. But its not a good idea to do it (unless you really know what you're doing), for some different reasons.

[Paul J.]

Re: Nuts and bolts Restoration

Danny, blasting them is the way to go. If you wish to wire wheel them, clamp them firmly in a vise. Let the wire wheel do the work and don't push it.

Dennis, I wanted a tumbler for years, but did'nt buy one becuse of the poor reviews on the web. One comment was particularly influencial. He said that he could do a better job in his blasting cabinet, although it required more work.

Paul

[Daniel H.]

Re: Nuts and bolts Restoration

Thanks guys, I had an analysis of the bolt done at work today with the result showing zinc plating on it. The bar nut as in Mike's picture came back with no coating on it as he stated, but, the steel is made out of low chromium steel which will help in preventing rust. So I guess I will wire brush and re-plate the bolts and just apply a sealer onthe natual parts.

[Dennis O.]

Re: Nuts and bolts Restoration

Paul,

My blast cabinet was $1099.00. The tunbler was about $60.00. I'd rather use the tumbler if I have something else in the shop to do that day. Also, it does make a little noise, but not nearly as bad as an adequate air compressor. Throw 'em in, check every couple of hours, and pretty soon they're done.

Amazon.com is starting to be my new best friend. The customer reviews are very helpful in separating the wheat from the chaff. I guess it comes down to personal choice.

[Troy P.]

Re: Nuts and bolts Restoration

Got my new in the box tumbler on ebay and the media at Harbor Freight.

I had hoped a tumbler was the answer. But I have been disappointed with the results. Even after leaving the parts in overnight. I first tried the green plastic pyramids. Little help. So I switched to a more aggressive ceramic cone. Still not great.

Suggest putting the tumbler on a rubber pad to help cut down the noise.

[Tom R.]

Re: Nuts and bolts Restoration

I've media blasted bolts then used Eastwood Metal Blacking then treated with Boeshield for black phosphate.

For Zinc plate I used their Zinc/Tin Electroplating system. The plate nut in the last photo is just media blasted then treated with Boeshield, the '65 JM calls for it to be natural finish.

Mike

I've used both of the Eastwood products you so well illustrate great results. The metal blackening did well initially but after a year, flush rust has taken over the surfaces. What's interesting about your method is the use of Boeshield...new product I'm not familiar. How has the metal blackening held up over time using Boshield. Interesting stuff! I could use it for the bike as well

The zinc plating I probably wasn't patient enough but was disappointed with its results.

[Grant W.]

Re: Nuts and bolts Restoration

Hi Daniel
Well to get it a natural finish!!!
This is what I did to the sway bar link. It supposed to be a natural finish. I took the rusted link. Bead blast it, then wire wheel it. Then boiled it in my zinc phosphate solution(which I have to last me another 20 years) which put a small coating on it. Then I experimented by using some steel wool and rubbed some of the phosphate off. Then I re torched the weld spots on the links. Looked like natural steel.
It came out pretty good. I also did that to my 1/2 shafts and drive shaft. Came out pretty good as to natural finish. If you search 1/2 shaft finish you can probably find the link and picture that I added.
So you may want to bead blast your bolts and use the method I did.
If you want to pm me then I can go in more detail
Hope this helps.
Grant

[Jeffrey S.]

Re: Nuts and bolts Restoration

I have posted this several times but the product is so good I will say it again- nothing removes rust as well as Evapo-Rust which is available all over. Parts go in like they were on the Titanic and come out like new. Of course it won't remove pitting, etc. but then nothing will. It is claimed that there is no acid in it (who knows) but after sticking my hand in to retrieve some parts with no effect I believe it to be very safe. If a part is not too rusty, only an hour or 2 will be satisfactory but most parts require an overnight stay. A gallon costs about $22 and is used over and over again. For plating I use the Caswell CopyCad for zinc, and Shooters Solution for black phosphate.
Jeff

[Dan D.]

Re: Nuts and bolts Restoration

I agree. There are so many rusty parts on my Corvette I do a lot of overnight soaks.

I put my hands in it a lot and don't see how it is any different than putting them in water. You can use it over and over, but I have found that once it gets dark and dirty it looses its effectiveness. Best price I have found is Tractor Supply. -Dan-