Rust

[Thudman]

The dealer failed to wash the chassis upon deliv from Winnie in the winter. Rust showed up after about a year, but not bad. Became progressively worse.

After a fun time of preparation (scraping, wire brush, etc) I sprayed phosphoric acid (Ospho) thanks to this forum. Seemed to work well. Put a coat of black paint over it. Hope it holds up. Regretfully, did not take before/after pix.

Thanks to all who contributed to the "rust" forums!

Thudman

[Thudman]

The dealer failed to wash the chassis upon deliv from Winnie in the winter. Rust showed up after about a year, but not bad. Became progressively worse.

After a fun time of preparation (scraping, wire brush, etc) I sprayed phosphoric acid (Ospho) thanks to this forum. Seemed to work well. Put a coat of black paint over it. Hope it holds up. Regretfully, did not take before/after pix.

Thanks to all who contributed to the "rust" forums!

Thudman

[John_Canfield]

Don't be surprised if the rust reappears at some point in the future unless you got every speck of it with sanding and wire brush. Even if it does reappear, you're on the right track to keep it under control.

One project I want to tackle when we get back to the ranch is to build a sandblaster for the express purpose of de-rusting some areas of my coach.

Also been thinking about replacing the steel facade in the plumbing bay with aluminum.

[smlranger]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by John_Canfield:
Don't be surprised if the rust reappears at some point in the future unless you got every speck of it with sanding and wire brush. Even if it does reappear, you're on the right track to keep it under control.

One project I want to tackle when we get back to the ranch is to build a sandblaster for the express purpose of de-rusting some areas of my coach.

Also been thinking about replacing the steel facade in the plumbing bay with aluminum. </div></BLOCKQUOTE>

John,

I got a pretty good media blasing gizmo from Sears for less than $100. If you've got a good air compressor, it works just fine. I got my blasting media from Northern Tool and it very quickly removes all rust.

[Thudman]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Don't be surprised if the rust reappears at some point in the future unless you got every speck of it with sanding and wire brush. </div></BLOCKQUOTE>

John: I thought the Phosphoric Acid (Ospho) was supposed to make the rust turn into primer, by changing negative electrons to positive (or some such magic).

Thudman

[John_Canfield]

Gary - buying a cheap Harbor Freight or Northern Tool sandblaster is absolutely under consideration.

Thud - my opinion is that everywhere the phosphoric acid actually is in contact with will convert chemically to something inert as far as rust is concerned, but the rust that is not contacted by the acid might still be active.

This is just an opinion - I am not a chemist or a metallurgist. I do know rust is extremely difficult to completely eradicate unless you prepare down to pristine and bare metal and then immediately prime or coat.

In any case, your action will either stop or slow down any further rusting, so you did good

[Pubtym]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by smlranger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by John_Canfield:
Don't be surprised if the rust reappears at some point in the future unless you got every speck of it with sanding and wire brush. Even if it does reappear, you're on the right track to keep it under control.

One project I want to tackle when we get back to the ranch is to build a sandblaster for the express purpose of de-rusting some areas of my coach.

Also been thinking about replacing the steel facade in the plumbing bay with aluminum. </div></BLOCKQUOTE>

John,

I got a pretty good media blasing gizmo from Sears for less than $100. If you've got a good air compressor, it works just fine. I got my blasting media from Northern Tool and it very quickly removes all rust. </div></BLOCKQUOTE>

Be sure to get safety face plate shield and nasal mask...

[NeilV]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Pubtym:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by smlranger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by John_Canfield:
Don't be surprised if the rust reappears at some point in the future unless you got every speck of it with sanding and wire brush. Even if it does reappear, you're on the right track to keep it under control.

One project I want to tackle when we get back to the ranch is to build a sandblaster for the express purpose of de-rusting some areas of my coach.

Also been thinking about replacing the steel facade in the plumbing bay with aluminum. </div></BLOCKQUOTE>

John,

I got a pretty good media blasing gizmo from Sears for less than $100. If you've got a good air compressor, it works just fine. I got my blasting media from Northern Tool and it very quickly removes all rust. </div></BLOCKQUOTE>

Be sure to get safety face plate shield and nasal mask... </div></BLOCKQUOTE>

One with vacuum recovery would be very tempting if not for the price.


See:

http://www.northerntool.com/webapp/wcs/stores/servlet/p...t_6970_138744_138744

[John_Canfield]

Neil - that's a new model from a less than a month ago when I looking around there. I think it would be fun to try to build one - they aren't at all complicated.

[NeilV]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by John_Canfield:
Neil - that's a new model from a less than a month ago when I looking around there. I think it would be fun to try to build one - they aren't at all complicated. </div></BLOCKQUOTE>

I have been tempted for about 20 years since I saw one in the WWGraingers showroom in Boston.

I has got to be one great vaccuum to deal with the volume/velocity of the air and dust comming out of the nozzle.

[WALLY NJ]

Hi
Let me tell you about Sand Blasting.
1st of all.......... IT GETS EVERYWHERE.....EVERYWHERE!
no matter how great you mask off an area ,, it will get in somewhere...***
Unless you take the part off and blast it somewhere not near the coach...
2nd you need gloves HOOD... turtle neck mask again,it gets everywhere,if you know what I mean.
3rd DO NOT USE BEACH&lt; POOL OR CEMENT SAND. you will be wondering why you have a raspy cough later, also this little thing called silicosis , but I have only seen that in bridge painters shipyard sandblasters.
Get your self some black diamond or equivalent...manufactured abrasives for sand blasting..........BUT.....
I would seriously look into power washing then hand brusing if the piece is question is still on the coach
The edges of my Adventurer by the compartments was getting flaky , I pressure washed it, then wire brushed them . then sprayed it with that rustoleum that supposedly converts rust to an inert coating ( Seems to be holding up, 5 months or so, but the jury is still out on it)

I have sand blasted quite few things ,,,,,, it does make short work of getting rid of rust,,,but its truly a dirty job,,,, consider the alternatives first.

[rgrstndgby]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I sprayed phosphoric acid </div></BLOCKQUOTE>

Thudman, we may have talked about phosphoric acid before, so I'll try to be brief. I had an Ornamental Iron contracting business for 30 years. When we prepared our products for paint, we wiped it thoroughly with a dilute phosphoric acid. That did 2 things for us. It removed any oil, and also any light rust from the surface. It also left an "Iron Phosphate" coating on the raw steel. ( so I am told by my supplier).. The IP deposit was a "binder" for the paint that was applied, and indeed it do so, BUT, if any surface that was cleaned with the PA was not thoroughly coated with paint, it would rust that afternoon.. and thats in "Its a DRY heat" Tucson. In fact, when we got a customer that wanted the product to rust, we washed it with PA, and nothing else, and RUST it would..So, if you are using PA to clean away old rust etc., make certain you get those areas covered completely with new paint..or you will have more rust than ever. Still not very brief, best I can do... ..rgr... On edit, another result of using PA, is that it slightly etches the surface of the treated material, giving the material some "tooth", a better surface for paint adhearance. Probably not a factor in your application.

[peter griffin]

John you are correct. If you don't get all the rust off it will come back. I used a walmart brand of rust stop/preventer and then primed and painted. The rust came back a year later but not as bad.

[porscheracer]

I've had good luck by power washing, wire brushing away any scale, and primering with Rustoleum Rust Converter (a paint that has phoosphoric acid in it). After 24 hours paint with whatever you want; but make sure the entire area is sealed with the Rustoleum and final coat.