ArdWrknTrk Posted March 21 Share Posted March 21 I often use acid to clean a part. it works amazingly. but then I have to smell it. neutralize and clean. it too is a process which take time and care. but when done right you have all of the available steel left to work with. too often we abrade the part and remove much of the good steel and still have rust pores. unless the rust is neutralized it can contain enough oxygen to continue to grow under a perfect seal. "Rust Never Sleeps".... It's mostly sulfuric or hydrochloric that are awful. Phosphoric acid, like Kleen-Strip Concrete and Metal Prep pretty much only needs rinsed off when it's done. Oxcylic or Citric acid don't smell too bad. Citric is REALLY cheap, in bulk Link to comment Share on other sites More sharing options...
viven44 Posted March 21 Author Share Posted March 21 You can remove all the rust with acid. It will eat all the iron oxide before it touches solid metal. Chemistry is fun! (and useful, sometimes) Yes chemistry is fun! 25% of my job is to come up with ways to prevent copper corrosion in metal traces used in electronics. With a fab, there are even other methods at disposal to clean metals such as plasma etch, reactive iron etch using oxygen, fluorine, etc aside from wet etch chemistries. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted March 21 Share Posted March 21 Yes agreed.. neutralizing has to be done to let the metal stop etching. The problem with neutralizing is that it is a basic solution (PH>>7) and oftentimes an oxidizer in-of-itself, and therefore needs a really good water rinse to rid of all the excess chemistry. Before it is removed it will do the job of forming a non-zero oxide layer (which is needed). Most paints/polymers rely on an oxide bond as native/bare metal doesn't have any good chains to bond to. The issue however is that the POR/paint, if and when it delaminates, you have almost fresh metal underneath that is a nice food source for trapped air/moisture that gets under the delaminations. Sounds like POR-15 is pretty robust in that department, but I assume it needs a good process of application to ensure no polymer cracking, etc. POR metal prep's MSDS shows to have phosphoric acid and alcoholic base both working in unison to etch and oxidize. I am leaning more and more towards physical removal, and I have always preferred that. I like that because it will remove any rust that is not adhered well and then whatever rust that is indeed still present is bonded well to the base metal really well and also a decent passivator. As mentioned, many of the paint over rust chemistries / polymers / primers do rely on a slightly oxidized metallurgy to form a good bond so some native rust/oxidation is preferred. My neighbor needs to deal with either chemical residues in the alleyway or maybe the sound of air compressor running!! Or..... just use an acid etch primer, like is sold just about everywhere. 💡 It certainly doesn't need any extra steps . Link to comment Share on other sites More sharing options...
viven44 Posted March 21 Author Share Posted March 21 Or..... just use an acid etch primer, like is sold just about everywhere. 💡 It certainly doesn't need any extra steps . I have always wondered about those. Let me see what I find after media blast ! Maybe media blast will thin-out the metal some more and now I need to beef it up by building it up with a fiberglass filler. I wish I had media blast while I was doing the cast iron intake manifold. It would have cleaned it up awesome!! Link to comment Share on other sites More sharing options...
viven44 Posted March 22 Author Share Posted March 22 I have always wondered about those. Let me see what I find after media blast ! Maybe media blast will thin-out the metal some more and now I need to beef it up by building it up with a fiberglass filler. I wish I had media blast while I was doing the cast iron intake manifold. It would have cleaned it up awesome!! Any ideas of what would cause that rust pattern? Trying to guess what kind of water leaks that may have to be addressed in the cab.. or if this is just from water from shoes that soaked the carpet Link to comment Share on other sites More sharing options...
Gary Lewis Posted March 22 Share Posted March 22 Any ideas of what would cause that rust pattern? Trying to guess what kind of water leaks that may have to be addressed in the cab.. or if this is just from water from shoes that soaked the carpet I would check the seal around the windshield. The mastic that was used dries and cracks and then leaks. So I'd put a hose on it and see if you have a leak. Link to comment Share on other sites More sharing options...
BigBrother-84 Posted March 22 Share Posted March 22 Any ideas of what would cause that rust pattern? Trying to guess what kind of water leaks that may have to be addressed in the cab.. or if this is just from water from shoes that soaked the carpet Water goes down… So in your pict, left part of the rust surely comes from the front retaining bolt for the seat railing. Silicon-seal it when you’ll put back your seat. For the right part, this could be water from windshield as Gary said, or from some free hole in the firewall. If it was from boots, well, the left side should be rusted same as right, unless the previous owner was a one-legged person. Link to comment Share on other sites More sharing options...
viven44 Posted March 22 Author Share Posted March 22 Water goes down… So in your pict, left part of the rust surely comes from the front retaining bolt for the seat railing. Silicon-seal it when you’ll put back your seat. For the right part, this could be water from windshield as Gary said, or from some free hole in the firewall. If it was from boots, well, the left side should be rusted same as right, unless the previous owner was a one-legged person. Lol. who knows maybe both sides were one-legged occupants and why they wanted an automatic transmission. Can you please expand a bit on "left part of the rust surely comes from the front retaining bolt for the seat railing.." not sure I follow. Link to comment Share on other sites More sharing options...
viven44 Posted March 22 Author Share Posted March 22 I would check the seal around the windshield. The mastic that was used dries and cracks and then leaks. So I'd put a hose on it and see if you have a leak. Yes good idea. I'll run a hose before installing new carpet. Link to comment Share on other sites More sharing options...
BigBrother-84 Posted March 22 Share Posted March 22 Water goes down… So in your pict, left part of the rust surely comes from the front retaining bolt for the seat railing. Silicon-seal it when you’ll put back your seat. For the right part, this could be water from windshield as Gary said, or from some free hole in the firewall. If it was from boots, well, the left side should be rusted same as right, unless the previous owner was a one-legged person. I suspect that this bolt lets water flow into the cab. Link to comment Share on other sites More sharing options...
Recommended Posts