Acid dipping advice
Discussion
Mk1 capri, heavily modified in the 70's to a dire standard and subsequently repaired and further modded by myself in an even worse way..
Got a few areas remaining that will need professional attention namely the scuttle panel, rh a panel, small section of rear floor pan. And I'm sure that there will be more revealed..
these parts are beyond me so someone who knows what they are doing can do then. Beforehand though I am considering getting the car dipped to derust everywhere (including the repairs that I've carried out and haven't treated properly )
Questions are, how should I prep the shell prior to sending it away, thinking of welding a couple of bars under the sills to allow it to be lifted easier, but then this would make repairs harder?
How much metal is removed in the acid? Surface rust should disappear but then how much steel would be left?
After dipping the car then goes to the bodyshop and then presumably goes back to be galvanised/e-coated, would it not rust heavily in this interim period?
I know to drill holes in all the trap areas to allow liquid in and out again.
Got a few areas remaining that will need professional attention namely the scuttle panel, rh a panel, small section of rear floor pan. And I'm sure that there will be more revealed..
these parts are beyond me so someone who knows what they are doing can do then. Beforehand though I am considering getting the car dipped to derust everywhere (including the repairs that I've carried out and haven't treated properly )
Questions are, how should I prep the shell prior to sending it away, thinking of welding a couple of bars under the sills to allow it to be lifted easier, but then this would make repairs harder?
How much metal is removed in the acid? Surface rust should disappear but then how much steel would be left?
After dipping the car then goes to the bodyshop and then presumably goes back to be galvanised/e-coated, would it not rust heavily in this interim period?
I know to drill holes in all the trap areas to allow liquid in and out again.
In theory, the acid should not remove any solid metal, it just dissolves the rust - if you have surface rust, that would go but the metal underneath would remain, and you would need to assess whether the remainder has thinned to a point where it should be replaced.
My concern is that something with an internal panel (for example, sill section on MGB has inner, castle and outer) where the inner and outer are good (or have been replaced) but the centre is not, might lead to the internal piece dissolving and you wouldn't know it. I guess it depends on whether your car has any areas like that.
My understanding of the process, which is not first hand, is that you have the dip followed by the e-coat, then go for repairs, then go back for e-coat again. Or get lots of surface rust on the bare metal in the interim, as you noted.
At the current cost of the dip and e-coat process, do you think you'll gain enough from it to make it worthwhile? And if it's just small areas that are affected, have you considered one of the blasting options instead?
My concern is that something with an internal panel (for example, sill section on MGB has inner, castle and outer) where the inner and outer are good (or have been replaced) but the centre is not, might lead to the internal piece dissolving and you wouldn't know it. I guess it depends on whether your car has any areas like that.
My understanding of the process, which is not first hand, is that you have the dip followed by the e-coat, then go for repairs, then go back for e-coat again. Or get lots of surface rust on the bare metal in the interim, as you noted.
At the current cost of the dip and e-coat process, do you think you'll gain enough from it to make it worthwhile? And if it's just small areas that are affected, have you considered one of the blasting options instead?
itannum990 said:
I have considered blasting, it would be far cheaper (which is welcome) but I'd forever be worried about the inside of box sections. How good is dinitrol and similar rust converters? I have been liberally applying/throwing it at everything as i go around?
I'm not convinced rust convertors are a cure-all for anything, though I have used some as a belt-and-braces approach when I think I've cleaned it up well enough but not completely sure. Keep in mind that if you go for acid-dipping, all the stuff you've been applying will be gone as well of course.The only way you'll be sure about the inside of box sections, whether you blast (which won't affect them) or dip (which might, and might cause a hidden part to disappear) is to have a look. There's some very small "spy" cameras with long leads on eBay for not much money, might be worth getting one and feeding it into your box sections to see what they're like.
droopsnoot said:
I'm not convinced rust convertors are a cure-all for anything, though I have used some as a belt-and-braces approach when I think I've cleaned it up well enough but not completely sure. Keep in mind that if you go for acid-dipping, all the stuff you've been applying will be gone as well of course.
The only way you'll be sure about the inside of box sections, whether you blast (which won't affect them) or dip (which might, and might cause a hidden part to disappear) is to have a look. There's some very small "spy" cameras with long leads on eBay for not much money, might be worth getting one and feeding it into your box sections to see what they're like.
Ooh camera is a good idea. Good call young man. I could even use it on the car when I've finished playing SAS spy perving gamesThe only way you'll be sure about the inside of box sections, whether you blast (which won't affect them) or dip (which might, and might cause a hidden part to disappear) is to have a look. There's some very small "spy" cameras with long leads on eBay for not much money, might be worth getting one and feeding it into your box sections to see what they're like.
The whole idea is to get rid of all the underseal, filler and rust before any repairs are undertaken. It makes it a lot easier for the guy that's going to be welding your fresh metalwork in if it's dipped then left bare.
Don't worry about it going rusty again, it will, but you'll send the shell back to get re-dipped then e-coated very soon afterwards to preserve the whole thing after all the repairs are done.
Regarding preparation: I don't think you'll really need a jig or a stand for the shell. Most people get away with manhandling the shell onto a few old tyres on the bed of a trailer. The dipping firms can assist with a forklift at the other end.
Make sure you take off any aluminium components from the shell before it goes for dipping - the chemicals will eat it.
Don't worry about it going rusty again, it will, but you'll send the shell back to get re-dipped then e-coated very soon afterwards to preserve the whole thing after all the repairs are done.
Regarding preparation: I don't think you'll really need a jig or a stand for the shell. Most people get away with manhandling the shell onto a few old tyres on the bed of a trailer. The dipping firms can assist with a forklift at the other end.
Make sure you take off any aluminium components from the shell before it goes for dipping - the chemicals will eat it.
xjsracer44 said:
I had an A35 race car dipped a few years ago & whilst it was really good at getting rid of the rust I wouldn't get another car dipped as the acid kept bleeding out of the bodywork seams for years afterwards & ruining the paint.
I'm hearing this repeatedly the more I research. Whislt final finish I do not care about, and I mean it, this car will be ratty as a ratty rat, I don't think I like the idea of acid getting pooled up in places for eternity. Had a slight change of thought. I need to buy a compressor, why don't I buy one, and a blaster, and do it myself?
Messy, yes, tume consuming yes, but my time is free and my garage is sweepupable so any reason why no?
Very time consuming with the kind of compressor you can run from domestic mains supply. I've been doing bits and pieces of my restoration, using a selection of large plastic bags as adaptable blast cabinets, and it works reasonably well except that I spend more time either waiting for the compressor to catch up, or unblocking the media pickup hose.
I guess it depends on how much of it needs to be blasted - you can get rid of a lot of surface rust using an appropriate disc in the angle grinder - twisted wire brushes and the hard sponge disc can get rid of paint quite quickly, and the twisted wire brush will also "highlight" any thin parts of the bodywork. And by "highlight", I mean "turn into holes". But that's better than painting over them and having them come back later.
I guess it depends on how much of it needs to be blasted - you can get rid of a lot of surface rust using an appropriate disc in the angle grinder - twisted wire brushes and the hard sponge disc can get rid of paint quite quickly, and the twisted wire brush will also "highlight" any thin parts of the bodywork. And by "highlight", I mean "turn into holes". But that's better than painting over them and having them come back later.
droopsnoot said:
Very time consuming with the kind of compressor you can run from domestic mains supply. I've been doing bits and pieces of my restoration, using a selection of large plastic bags as adaptable blast cabinets, and it works reasonably well except that I spend more time either waiting for the compressor to catch up, or unblocking the media pickup hose.
I guess it depends on how much of it needs to be blasted - you can get rid of a lot of surface rust using an appropriate disc in the angle grinder - twisted wire brushes and the hard sponge disc can get rid of paint quite quickly, and the twisted wire brush will also "highlight" any thin parts of the bodywork. And by "highlight", I mean "turn into holes". But that's better than painting over them and having them come back later.
Would a 150 litre tank be sufficient? I guess it depends on how much of it needs to be blasted - you can get rid of a lot of surface rust using an appropriate disc in the angle grinder - twisted wire brushes and the hard sponge disc can get rid of paint quite quickly, and the twisted wire brush will also "highlight" any thin parts of the bodywork. And by "highlight", I mean "turn into holes". But that's better than painting over them and having them come back later.
I don't know really. Mine's a 50 litre tank, which isn't really big enough for much but better than the cheapo 24l entry level ones, but it's got a 3hp motor which I believe is as big as I can go on 13A. I've considered upgrading, but I just figured that when the tank empties (which will take three times as long to happen) the same spec of motor will then take three times as long to pump it back up again. So I haven't done anything more about it.
Hard to say - a minute, perhaps? Next time I've got it set up I'll give it a go and post back. I also need to experiment with the pressure - I've been using it on maximum flow, but it struck me the other day it might be better to reduce the pressure, based on something I was reading elsewhere.
http://www.envirostripukltd.com/portfolio/auto-res...
The garage that are restoring my 61 Flat Floor E Type are using this company for the stripping.
They claim the following
No harsh chemicals are trapped in the seams & box section which can cause issues later in life
No indentation to the shell from shot blasting
No sand / grit trapped in seam joints
Saves time and money for the customer when the shell goes into the paint shop
The body shell stays on one secure process frame throughout the process eliminating any damage to the shell
The garage that are restoring my 61 Flat Floor E Type are using this company for the stripping.
They claim the following
No harsh chemicals are trapped in the seams & box section which can cause issues later in life
No indentation to the shell from shot blasting
No sand / grit trapped in seam joints
Saves time and money for the customer when the shell goes into the paint shop
The body shell stays on one secure process frame throughout the process eliminating any damage to the shell
There's a chap on the etypeuk forum that had his series 1 dipped
I suggest you search and look at the horrors dipping presented him with
I have similar experience with panels on the seems rusting right through even though the car hasn't seen a drop of water since the 80K resto...I feel sick just thinking about it
Acid not neutralised or extracted properly and carried on eating away at the metal. Mine was ecoated and everything
I suggest you search and look at the horrors dipping presented him with
I have similar experience with panels on the seems rusting right through even though the car hasn't seen a drop of water since the 80K resto...I feel sick just thinking about it
Acid not neutralised or extracted properly and carried on eating away at the metal. Mine was ecoated and everything
vpr said:
There's a chap on the etypeuk forum that had his series 1 dipped
I suggest you search and look at the horrors dipping presented him with
I have similar experience with panels on the seems rusting right through even though the car hasn't seen a drop of water since the 80K resto...I feel sick just thinking about it
Acid not neutralised or extracted properly and carried on eating away at the metal. Mine was ecoated and everything
Was it the same company that I posted above? I suggest you search and look at the horrors dipping presented him with
I have similar experience with panels on the seems rusting right through even though the car hasn't seen a drop of water since the 80K resto...I feel sick just thinking about it
Acid not neutralised or extracted properly and carried on eating away at the metal. Mine was ecoated and everything
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