1844 replies to this topic

[Andy_]

This is a good inspiration for me to start 

[Petrol]

 

By the way, is anyone else interested In Bilt Hambers offer of 10% discount on Electrox aerosols? It's not worth it to set a discount code up for 1 member

 

 

I could stick a thread on TMF+ they love a bargain discount

 

BM

 

Good idea, if you can send me a linky I would appreciate it. Might be worth pointing out that after some long conversations with the guy that developed their range of products, I can offer quite a bit of tech support. Just to add, I don't work for the company and have no financial gain from their sales. I am just grateful I can speak to someone and get straight answers about rust and how to deal with it.

With a Mini, it comes in abundance!

 

We all need inspiration Andy_ Sometimes I despair at the amount of work involved

 

Pete

[BishopMaverick]

Topic posted in TMF+: http://www.theminifo...ount/?p=2789813

 

I think TMF+ posts will only display for TMF+ subscribers... Always worth the subscription though, only a fiver and the list of discounts is very respectable. You could get your fiver back on one order to M-Machine or Mini Spares who both offer discounts amongst many others, including insurance companies and the popular Mini Magazine. (I think that was a plug )

 

In my post a stuck a link to this topic but any interest from the tread I'll PM you if thats okay, just to avoid it hijacking this thread.

 

Lets hope there is some more interest in this discount... will be useful to me in my rebuild.

BM

 

 

[Petrol]

BM, drop me a PM if a few are interested   I buy most of my stuff from J&K supplies (maybe that was another plug )

 

The bottom of Mini doors are unusual as they are pretty flat. The downside to this is any imperfections can easily be seen. When I fitted the skins, there was some slight rippling which I filled with stopper. The problem with panels in the primer / stopper stage is that it's hard to see what's going on since the finish is matt. The best way around this is to use gloss paint to fill any imperfections. It's quite time consuming but the last thing I want is ripples at the bottom of the doors.

This is what I am doing.

 

Door sprayed in gloss then flatted back by hand with a large block

 

 

This reveals high and low spots like this

 

 

The way to get it absolutely flat is to sand until all the low spots are gone. If you go to bare metal then it needs spot priming with etch and more gloss. The goal is to end up with with this

 

 

A totally matt finish in gloss paint.

 

There are many pitfalls spraying gloss over primer, stopper & filler but to get it absolutely right, this is the best way

 

Hope that was useful

 

Pete

 

 

 

 

[jackgreen91]

Mate this is the best thread I've read in terms of paint and prep.

 

Really love the results you're getting and help you're giving to all on here. Much of the results seem better than original or new, so good one.

 

I've done a bit of painting with not much success so reading your tips is helpful. I find that I always have rust coming back through so I might try that Deox gel.

 

I am also the new owner of a pot blaster for which I'm going to build a cabinet and have a similar result hopefully. Just need the money to buy all the paint now!

 

All the best with the mini, looks great.

 

Cheers, Jack

[Petrol]

Thanks for the kind words Jack, that's what forums are all about - sharing info

Rust is a right pain to deal with, it's hard to get out and it's hard to stop it coming back. The carbon deposits I mentioned earlier in the thread are the biggest pain. If you can get rid of this and get some proper zinc primer in the seams then it's about the best you can do. Whilst Bilt Hamber's zinc is "self sealing" I am planning on adding some extra protection. I guess only time will tell if it works

 

Pete

[jackgreen91]

Thanks for the reply, the dreaded tin worms! There seem to be a lot more types of rust to what I thought! I have had a look on the discount thread and would be up for a discount on the bilt hamler but I'm not ready for paint yet so I'll keep it in the list.

 

What words of advice could you give on chipping paint. I recently sprayed a bicycle frame from bare metal (nitromors) with white upol primer, not etch. Then 'colourmatch' 1K rattle can, then flatted it and 2K lacquer. I did the 2K at uni and don't know what ratio he did it or whether he used just thinners. I don't think he used hardener when mixing, I gave it about 3 coats of clear coat. My suspicions are that maybe the nitromors has stopped the primer holding, or that the primer wasn't etch primer, (I didn't know much about it then), or that it was rather chilly when I was painting. Other than that I'm not too sure. To describe the chipping, if you give it a knock with something by accident like a spanner it will go to bare metal, and on the contact points for axles etc it will just chip off to bare metal, seems a little odd. I just wanted to know the cause before attacking the mini and having the same effect!!

 

Next, you advise against powdercoating subframes, I'm a bit unsure of how to paint mine at the minute. I was going to go for blast and powdercoat but your suggestion of chassis black over powder coating has changed my mind.

 

Sorry to hijack this helpful thread but you seem to hold a vast knowledge that I'd like to dig into!

 

Cheers, Jack

[rally515]

 

Next, you advise against powdercoating subframes, I'm a bit unsure of how to paint mine at the minute. I was going to go for blast and powdercoat but your suggestion of chassis black over powder coating has changed my mind.

 

 

 

I galved mine if thats any help against rust to you ?

Cost a bit but its hot dipped & pretty hefty coating (sandblasted before dipping).

 

Cliff

[Petrol]

I have paid my subscription so I can see whats going on with the group buy.

 

Jack, I will post more info on surface prep, primer, filler & paint when I get chance. Please bear with me but as always things are not quick and easy. Sounds like poor prep on you bike frame Jack, that's why the paint chipped. When I get some time, I will post up some more info if it helps

 

Pete

[sonikk4]

Going along the what to coat the subframes with route, if its a show car then powdercoat will work fine, if however its going to be a daily or more frequent use then galvanising followed by paint would be the route to go.

 

There has been questions raised about warping etc but the general consensus is they will be fine. I will be getting a set done for Paddy. I am adding extra seam welds where possible to add extra strength.

[Petrol]

Powder coat is not the way to go really. The downfalls out weigh the benefits. Galv lasts a long time as long as it's done right but again there pitfalls...

Just watch this thread, I will post up a load of info as I go.

 

Cheres

Pete

[Petrol]

Sorry to hijack this helpful thread but you seem to hold a vast knowledge that I'd like to dig into!

 

Cheers, Jack

I started typing a bit of info....

 

As with any job, there’s many techniques and products to ultimately achieve the same goal. These are the technique’s I use.

Rust
I’m not a big fan of rust converters like kurust. The problem is, if doesn’t work for whatever reason – poor product / improper application, it’s just going to come back. I mentioned earlier in this thread about carbon particles within the rust and how hard it is to remove. If the rust converter doesn’t penetrate the carbon and convert the rust behind it, it’s only a matter of time before the dreaded stains re appear. On a big job like reconstructing a shell that takes hundreds of hours, I think it’s worth going the extra mile to try to mechanically remove it.

Chemical rust removers make life easy. I use Deox C for small parts. This is a liquid that dissolves the rust. For areas where immersion is not possible a Gel is available. It’s a good idea to scrub the parts with wire wool / scotchbright / toothbrush after a few hours / overnight before re dipping or reapplying the gel. Parts must have all paint removed and degreased before application. Once the rust has gone the part needs to be cleaned as Deox leaves a black deposit behind. The best thing I have found for this is turtle wax engine degreaser applied with a toothbrush. This is followed by a rinse in hot water and then dried.

I’m a big fan of shotblasting and I use a fine glass blast media. I blast everything – parts after deox application, seam welds after dressing basically as much as I can before paint. One of the benefits of shotblasting is it leaves a good key for primer.

Prep for primer.
It’s pretty simple, a blasted finish gives the best key especially for zinc primer. Just a quick one on new panels, most are finished black. This can be either ecoat (google that one it would take me hours to explain the process) or finished in chassis black. It’s easy to tell the difference, wipe some thinners on the panel, if paint comes off, it’s not ecoated and the chassis black needs to be removed and replaced with some proper primer. I do this with a rag and thinners. This one is important, paint thinners leaves a residue behind and it’s not good practice to use this as a degreaser for paint. The product to use is panel degreaser which is available from your local bodyshop supplier.

I mentioned a blasted finish is good especially when using a zinc primer, the reason for this is that you need good electrical contact between the steel and the zinc primer. When you have dissimilar metals in contact with each other, it creates a very small charge. This is how the zinc primer stops the steel rusting. Basically it sacrifices itself rather than the steel rusting. If you thought for example I will use every product available – kurust & zinc primer, it wouldn’t work as the kurust would create an electrical insulation between the steel and the zinc. Not simple this lot.

Took me a while to type that lot up. Is this info useful? If it is I will post up the next stage about various paints and protection methods

Best

Pete
 

[jackgreen91]

Great info. Will follow this thread when I get on a laptop. Thanks a lot for the effort to post too, really appreciated. I think before I get any more progress done to the mini I will build my cabinet for blasting as it will be a life saver and make parts look the bees knees.
What would you say in terms of painting moving parts such as the pedal box? For example, would they not rub the paint off again or is it a waiting game for the paint to harden. I suppose you would paint in one piece also so that the mating faces are not jeopardised by paint rather than painting in parts.

Thanks again, Jack

[Petrol]

Great info. Will follow this thread when I get on a laptop. Thanks a lot for the effort to post too, really appreciated. I think before I get any more progress done to the mini I will build my cabinet for blasting as it will be a life saver and make parts look the bees knees.
What would you say in terms of painting moving parts such as the pedal box? For example, would they not rub the paint off again or is it a waiting game for the paint to harden. I suppose you would paint in one piece also so that the mating faces are not jeopardised by paint rather than painting in parts.

Thanks again, Jack

 

Hi Jack,

I painted the pedal box in pieces. The best paint for something like this is 2K epoxy. It's also great on suspension components and subframes. 2K paint takes ages to fully cure at room temperature, depends on thickness but your looking at around a couple of months. This is one of the reasons I painted all the suspension parts early on so the paint will be fully cured.

 

Got the NS flitch panel on

 

 

Once dressed it was shot blasted

 

 

 

Then Zinc primed

 

 

I'm forcing as much zinc as I can into the seams. I thin it about 50% and It's surprising how far you can push it at 60 psi. There's runs and it's not pretty but that will easily be sorted out later.  Shell looks like this now

 

 

 

Pete

[Petrol]

Started prepping the new boot floor. I scuffed the ecoat with red scotch bright around the battery box seams then using 2k etch, spot primed it. It was then seam sealed.

 

 

This will eventually be stone chipped but it's better to seam seal first. The seam sealer also prevents the stone chip getting inside the box as some of the gaps were quite big.

 

The boot floor has a captive nut held in a pressed steel cage for the battery earth. I have no idea why it was designed like this as it's a very poor design and can lead to a poor battery earth connection. Decided to weld a nut onto a plate then spot weld the plate on. The strange dark patch is zinc primer where I forced it through the seams

 

 

I had to use the long arms on the spot welder to fit the plate

 

 

Spot welds are unsightly on the battery tray from inside the boot.

 

 

I appreciate this is covered but thought the best all round solution was to buy a liner

 

 

Pete