Wilk
Part of things
Posts: 528
|
|
Jun 13, 2016 19:46:41 GMT
|
Currently scraping the underseal from the underside of the car. Over the years there's a few areas of rust to the edges of the seams that need cleaning up and treating
Basically I've removed the underseal then either blasted the area or ground of the smal area of rust My issue now starts on where to go and in what order
The wheel arches are to be finished in paint to match the colour of the car. I'd like to also apply some smooth stone chip for protection. Do I first apply rust converter then epoxy primer then colour/stone chip then colour? Maybe apply zinc primer at some point?
For the underside I'm wanting to finish in black paint but what sort. I've already done the subframes springs etc in black POR15 and was looking to leave that as is without having to overpaint the bits. Will this be ok?
BTW, the car will be a fair weather drive only used for summer time runs.
|
|
Last Edit: Jun 13, 2016 19:47:41 GMT by Wilk
If it can be fixed with a hammer, then it must be an electrical fault
|
|
|
|
|
|
i don't really agree with rust convertors ....much better idea to crack on and remove all traces
once its clean choose one primer -epoxy being the best by far , no point in layering that with zinc or god knows what as it will sitting on top of the first product
then stonechip and some gloss
por15 doesnt need overcoating but may turn chalky if the sun gets at it
|
|
91 golf g60, 89 golf 16v , 88 polo breadvan
|
|
|
|
|
Removing all traces of rust isnt always possible. Say large sections of the underside have surface rust. Your not going to replace all the metal. If you cant get it blasted then you have to do something. Wire wheel the hell out of it, remove every single speck you can, but your never going to be able to remove every trace. I still wouldnt paint over that without treating it first.
Rust converters vary alot though. Ive been trying fertan at the moment, if you follow the pre wetting instructions it does seem to penetrate down to the base steel.
If I was to remove every trace of rust from my van id have to blast or dip the whole shell. Not possible. If I was to cut it all out I would literally have to remake every single panel from scratch and build a new van.
Even if you blast the shell there will be surface rust you cant see in nearly all seams too. Unless you un stitch every panel to blast inside every seam you need to do something else. I'm flooding every seam with rust converter then ill seam seal and wax oil to be sure.
Removing every trace is a nice idea but not always possible on stuff 40 years plus old.
|
|
|
|
at200
Part of things
Posts: 88
|
|
Jun 14, 2016 13:33:33 GMT
|
I would remove as much rust as you can. A Black and Decker powerfile is great for this. If you want to be really thorough you could use something like Bilt Hamber Deox gel to get into pitted rust. If you want to use a rust converter Bilt Hamber Hydrate 80 is good, but as said removal is better but not always possible. A good epoxy primer would be Lechler 29107 which is non iso and can be sprayed at home. Alternatively, you could use Bilt Hamber Electrox which can be sprayed or rolled. www.express-paints.co.uk/epoxy-primer-29107/You could then put on a stonechip like Gravitex and then top coat, or use something like Epoxy Mastic from Bilt Hamber, or epoxy mastic 12. Rust.co.uk have some products that I have often seen recommended and a good guide: www.rust.co.uk/3-treating-rust-the-rustbuster-way/t20/
|
|
|
|
|
|
Jun 14, 2016 14:06:29 GMT
|
Sandblast or whatever your best effort is to remove all rust and coatings from bellow.
Treat any suspect areas with POR or Chassis Saver. Be aware that POR and Chassis Saver will peel off smooth clean steel. Needs to be rough as it would be after rust is blasted away. I never just paint over rust: if I can see it, I will make an effort to get to clean metal with a wire wheel or blaster.
Spray everything in epoxy primer.
Coat the relevant bits in rocker-guard.
Paint over rocker guard.
Be aware that pebbled surfaces such as rocker quard and bed-liner collect dirt.
Myself? I stop at the rocker-guard stage for the underside. Unless it is a show car the underside is going to get dirty and paint just makes it worse.
|
|
|
|
slater
Club Retro Rides Member
Posts: 6,390
Club RR Member Number: 78
|
Underbody paint steps neededslater
@slater
Club Retro Rides Member 78
|
Jun 14, 2016 16:58:57 GMT
|
I use the por15 'metal ready' stuff to treat the underside. Even after blasting you need to do it as blasting won't get in the box sections or seams. Its phosphoric acid so reacts with the rust but not the steel I'm sure it helps.
Then primer. Epoxy is good but people tell me it's wrong to use it over anything other than bare metal. I'm not convinced, it works for me. Some people use etch primer first. Again not sure but I've never had problems with either method.
After primer do your stone chip and then go over with 2k colour
|
|
|
|
Wilk
Part of things
Posts: 528
|
|
Jun 14, 2016 20:03:12 GMT
|
Thanks for the replies folks
I have access to a blast pot to remove surface rust which is used in combination with grinders and flap discs. It's not excessive rust but as stated by someone earlier it's getting into seams that's the issue hence the rust converter idea just to make sure I've got to as much as possible without actually having to physically part the seam
|
|
If it can be fixed with a hammer, then it must be an electrical fault
|
|
|
|
Jun 14, 2016 20:09:54 GMT
|
That is why I used fertan in particular. Its thin so will creep.
You wet the rust first (scary!)
So the water will soak into any rust in the seam and the fertan will soak in properly. You need to wipe it off with water after 24hrs+ before you paint though, which means even more waiting for stuff to dry.
|
|
|
|
|
|
|
Removing all traces of rust isnt always possible. Say large sections of the underside have surface rust. Your not going to replace all the metal. If you cant get it blasted then you have to do something. Wire wheel the hell out of it, remove every single speck you can, but your never going to be able to remove every trace. I still wouldnt paint over that without treating it first. Rust converters vary alot though. Ive been trying fertan at the moment, if you follow the pre wetting instructions it does seem to penetrate down to the base steel. If I was to remove every trace of rust from my van id have to blast or dip the whole shell. Not possible. If I was to cut it all out I would literally have to remake every single panel from scratch and build a new van. Even if you blast the shell there will be surface rust you cant see in nearly all seams too. Unless you un stitch every panel to blast inside every seam you need to do something else. I'm flooding every seam with rust converter then ill seam seal and wax oil to be sure. Removing every trace is a nice idea but not always possible on stuff 40 years plus old. Holy thread revival! Just doing some research on this process. I'm about to finish off now with my underbody rust cleaning. I have Fertan ready to apply but looking for a suitable primer to paint over it. I would prefer a primer if available that can be brushed on given I'm working from underneath the car with limited access. I have 2k paint to match finish and intend a clear coat waxoyl over it. The Primer is the one I need advice on or recommendation. Be good to hear from someone who has experienced working with the Fertan. Thanks
|
|
1993 Mitsubishi Lancer Evolution 1 RS 1989 Mitsubishi Galant VR4
|
|
|
|
|
Removing all traces of rust isnt always possible. Say large sections of the underside have surface rust. Your not going to replace all the metal. If you cant get it blasted then you have to do something. Wire wheel the hell out of it, remove every single speck you can, but your never going to be able to remove every trace. I still wouldnt paint over that without treating it first. Rust converters vary alot though. Ive been trying fertan at the moment, if you follow the pre wetting instructions it does seem to penetrate down to the base steel. If I was to remove every trace of rust from my van id have to blast or dip the whole shell. Not possible. If I was to cut it all out I would literally have to remake every single panel from scratch and build a new van. Even if you blast the shell there will be surface rust you cant see in nearly all seams too. Unless you un stitch every panel to blast inside every seam you need to do something else. I'm flooding every seam with rust converter then ill seam seal and wax oil to be sure. Removing every trace is a nice idea but not always possible on stuff 40 years plus old. Holy thread revival! Just doing some research on this process. I'm about to finish off now with my underbody rust cleaning. I have Fertan ready to apply but looking for a suitable primer to paint over it. I would prefer a primer if available that can be brushed on given I'm working from underneath the car with limited access. I have 2k paint to match finish and intend a clear coat waxoyl over it. The Primer is the one I need advice on or recommendation. Be good to hear from someone who has experienced working with the Fertan. Thanks You can use a 2 pack primer - some forum readers like to call it an epoxy primer - it's the same thing - essentially a primer that is mixed with a catalyst to make it cure - depending on the product you may have to thin it slightly to get it sprayable - correct PPE is critical so gloves, cover all bare skin - ideally one of the disposable paper suits for spraying in, a decent air fed mask and plenty of ventilation through the workshop / garage - you can brush it on if required and best thing for the larger areas is a mini gloss roller - you still need the correct PPE but you could replace the air fed mask with a suitable face mask - you can purchase online but you are probably better off seeking out a good independent automotive paint supplier that is local to you. You may well get the odd forum reader that raves on about applying an epoxy mastic to the undersides of vehicles - this is an industrial product mainly utilised within the marine industry and completely the wrong product to apply on the underside of a car you are just storing up problems for the years to come by applying this. I would highly recommend applying a good quality seam sealer to any open seams / flanges once you have applied the primer. Bilt Hamber & Dintrol rust proofing products are far superior to that of the Waxoil brand variety and have been laboratory proven. Let me know if you need any further advice - good luck Chris
|
|
Last Edit: Feb 8, 2018 15:39:14 GMT by Deleted
|
|
hario
Part of things
S202 C300STD
Posts: 421
|
|
|
Don't underestimate the importance of protecting the cavities iwth Waxoil or equivalent.
never had any luck with rust converters, or wire wheels for that matter, I'd consider a soft flappy paddle wheel after wire wheel-ing
|
|
*S202 C300TD Wagon* Installed: OM606 & 722.6, Evo6 IC, S600AMG callipers & 345mm rotors. No catz. Leatherish seats.. Rust.. Future: DIY manifolds & turbo compound build. Built IP, & some kind of software. Less rust..
|
|
|
|
|
|
|
1993 Mitsubishi Lancer Evolution 1 RS 1989 Mitsubishi Galant VR4
|
|
at200
Part of things
Posts: 88
|
|
|
That's a high build primer, not an epoxy primer, isn't it? As I understand it, epoxy primers are more moisture resistant. I would think a high build primer is more intended for flat panels - doors and bonnets etc - where the purpose is to even out panel imperfections and sand it to get a flat surface for a top coat.I guess if the car is inside and you will be top coating fairly quickly high build would be ok.
|
|
Last Edit: Feb 9, 2018 9:45:49 GMT by at200
|
|
|
|
|
That's a high build primer, not an epoxy primer, isn't it? As I understand it, epoxy primers are more moisture resistant. I would think a high build primer is more intended for flat panels - doors and bonnets etc - where the purpose is to even out panel imperfections and sand it to get a flat surface for a top coat.I guess if the car is inside and you will be top coating fairly quickly high build would be ok. Its a 2 pack primer or has some would state an 'epoxy primer' - a primer that is cured by a hardener / catalyst and is completely suitable for the OP's intended uses - it cures to form a moisture resistant base that once keyed / sanded will provide a suitable base to accept final / top coats - confusion arises when owners apply a single pack / air drying primer which are moisture absorbent so unless the work is undertaken within a completely dry environment and within a small space of time of applying the single pack primer to the application of the final / top coat can cause endless problems by the primer absorbing moisture - when the top coat is applied the moisture is trapped underneath within the primer and therefore can cause paint interface / reaction problems where has 2 pack primers eliminate this problem.
|
|
|
|