Im after someone who can professionally underseal a car. im thinking a classic car place would be the best bet

if anyone knows of anything within say 40 miles of Barnsley south Yorkshire id rather give the money to someone that's recommended or a friends business .

please pass on details to me , thanks in advance

Can't help with a supplier, but I'm interested in the same subject.

I'm currently stripping my 205 GTI project shell of paint, underseal and seam sealer (of which Peugeot used an awful lot). Once stripped and welded it'll need resealing and I also think it might be better done professionally.

Not sure if this would do the job?

http://www.plowmanbrothers.com/speedliner.php

Not sure if this will help but I have a similar job to do on my Ford Anglia. The top/inside has been resprayed (told it was bare metal?) but underneath is very solid with a small amount of surface rust, I plan to wirebrush it off and then I plan to use the KBS products (similar to POR15 but can be used on clean metal) as I want a painted finish and they do a rust prevension paint in off-white to match the rest of the car.

My main experience of underseal is peeling it off in big chunks with floor pans and chassis rails attached. It used to crack and water would seep in between it and the metal work and be held there till it rotted out.

http://www.rust.co.uk/products/category/28117/epoxy-mastic-rust-proofing-chassis-paint/

Some very good products here, cant see why you need a professional to do it if your quite handy apart from access problems.
The MIL spec transparant wax they sell is good stuff too, waxoyl had a reputation for peeling but the newer stuff from dinitrol etc is much better.

Old underseal does eventually flake off. However, the worst stuff is when garages just wack it on over repairs, straight onto bare metal.
Metal needs to be clean, primed (etch best) and topcoated before underseal is applied. Better though is stonechip paint that can be overpainted. And then coated with a protective wax. Do all the cavities at the same time.

Just bought some dinitrol stuff, the thin MIL for boxes and seams, and the thick black stuff for arches and areas that take a hammering.

I believe dinitrol is what most oem use? it explains why cars don't go rusty any more. (fords excepted)

the car is an 04 monaro I just bought and they have very little underseal from new.

spoke to a few places who quote between 400 and 1000 quid .

due to not having a ramp and a steam cleaner I think it maybe a job for the pros.

although if I can find a ramp to rent out I may go for it.

I think it will be either dinitrol or bilt hamber I use.

I am certain you can get the underside steamed off for not too much cash. Then £100 for a few cans of whatever. Less if you have a compressor... (the aerosols contain less than half the material of the proper litre tins for the same cost approx)

Really difficult to remove underseal, horrible job, best way I have found is with a grinder and a wire wheel, for really thick stuff a heat gun and paint scraper gets the worst of it off then wire wheel off whats left. Hot underseal chunks go everywhere though, in your hair and clothes but once it's all off it's worth it.
I would not bother with getting a professional to put on new stuff though if it's just spraying a floor pan and no cavity protection, if you don't have an air compressor just hire one for the day and do it yourself. Dinitrol is good or 3M do a really good 2 pack epoxy underseal but it's very expensive .

Also far easier to turn the car over on a spit rather then tackle it from underneath on a ramp.

[Edited on 10/6/14 by Scuzzle]

best way to remove underseal is dry-ice blasting...another advantage: all other parts, like suspension, cables, calipers, brakes will get cleaned properly form all old dirt and llose rust by the dry ice...

dis-advantage: its not so cheap...but worth every penny..imo....