Blast Cleaning

[andrewh]

I am about to blast clean a really really good California OTS. Most of the cars I have blast cleaned before have needed quite a bit of panel work, so I have been less bothered about the effects of the blast cleaning itself on the panels. I am sure my last bonnet was ruined by the cleaner, and I have certainly experienced blasters who have buckled panels by concentrating the heat too much in one area. Would be interested in peoples experience on this, particularly the bonnet which I really do not want to damage. I assume it would be best to strip the bonnet into its various parts before doing this, but I wonder whether soda blasting may be a better option? Anyway, all thoughts much appreciated.

[Alty Ian]

Andrew.
It would be most unwise to blast the bonnet centre section, boot lid or rear bulkhead above boot lid, they should all be stripped and sanded. I didnt risk blasting them and the blaster I used was very very careful to keep the pressure down and blast in layers to avoid heat build up generally, but many wouldnt be that careful. I know of others who have ended up with undulating panels after being blasted.

To flat panels it just isnt worth the risk, stripping and sanding is very tedious I know but its the way to go for such panels.

Ian

[andrewh]

thank you Ian, I think you are bang on right, and you really need someone who knows what he is doing and is prepared to take his time doing the job. I was wondering whether soda blasting was an option as it may produce less heat build up, but I really don't know if thats the case for sure.

[mgcjag]

Hi Andrew.....I have one of the small home use sandblasters that has a valve to use soda....i have used it for some small items and even tried removing the paint on a coke can it did this easy without denting the very thin metal......it does produce huge clouds of white powder but it disapears once it rains.........dont know about the comercial sode blasters, assume they would use much higher pressure and do larger areas at once so would not go there........if its a job you wanted yo do yourself you could set up a tarpaulin sheet tent and just take your time doing small areas, would be easier than sanding.....

[PeterCrespin]

The underside of my stolen 'immaculate-metal' FHC was ice blasted. This has the advantage of leaving soft trim untouched.

[mark10337]

dry ice blasting is highly recommended, very gentle and doesn't damage more fragile areas.

[71 V12]

Hi Andrew,

A long way from Kent but It would be worth talking to Marawise, Eden Street Coventry.

Very experienced at blast cleaning E Types for Robey, Rod Jay and many others. Also very competitive.

Kevin

[andrewh]

thanks chaps. I imagine he has sandblasted two of mine then already! I will give him a call and have a word. I am favouring on me doing the bonnet and boot, and taking the underseal off and then getting the rest done outside.

[Jeremy]

Hi Andrew

Martin Robey (who is rebuilding my shell) had it shotblasted by these guys a couple of weeks ago - here are a couple of pics. He has used them for a long time and they clearly know what they are doing. Although MR did mark the roof and the scuttle "NO SHOT" for the avoidance of any doubt - they will be stripped by hand.




Incidentally MR said he would not use acid dipping under any circumstances...

[Quattrofrank]

Why is acid dipping not recomended at all? With all of the hidden places around a body this will be the only way to clean everything. Except cutting off firewall, channels etc and then reassemble.

[andrewh]

thanks. Acid dipping is extremely difficult to remove from hidden voids and especially seams where it remains, regardless of the so called neutralisation process, and then leeches out for ever more, ruining paintwork. I imagine it can be used on flat panels with none of the above, but all I hear from those that have had it done is they would not do it again.

[Jeremy]

I've no experience of it so I'm only repeating what Martin told me. He said that, in his experience, it is impossible to get rid of all the acid in the seams and it can leach out and attack the new paint. Perhaps there are acid dippers out there who successfully neutralise it. I don't know.

[andrewh]

I don't think so. Its not possible .