Underseal

[Storer]

I have now got my chassis upside down and thought this would be the ideal opportunity to under-seal the underside. I am planning to do the floor pan and alloy panels with something when I have finished riveting.

What product have other here used?

Did you paint it afterwards (if it was the type that would take paint)?

Or did you leave it until the car was complete?

Paul

[738 driver]

I think most leave them bare!
Maybe thinking ahead, what about a good quality cavity wax, it should protect whatever is underneath (floor/panelled area's) and could be removed relatively easily should you or a later owner choose to.

'Painting' the combination of alloy and various steels successfully requires careful preparation and specialist primers.

Edited by 738 driver on Wednesday 13th January 23:31

[Gulf LS3]

IF i was going to protect the underside of the car i would use a product called rubbercoat which 1 protects and 2 cuts down the noise of stones etc hitting the ali, i would definately use it under the front and rear inner arches to stop stones cracking the grp. If you use grippy tyres ie kumhos or toyos they pick up a lot of small stones and its not nice listening to them all hitting the inside of the clips.

i dont think i would protect the underside myself but thats just my view.

[pilbeam_mp62]

This is the stuff I used on the inside of the rear wheel arches - Isoflex Liquid Rubber :-

http://www.screwfix.com/search.do?_dyncharset=UTF-...

On the inside of the front wheel arches, I decided to try something different and I have stuck thin rubber sheeting on with contact adhesive, and then the edges tidied up with aluminium tape.

It looks the dogs b***ox, and I expect it to be very effective as well

Regards

[Steve_D]

On mine I used 'Hammerite Stonechip' aerosol to both coat the insides of panels and do the whole underside. Each time it goes for its MOT test I keep meaning to take a can along and touch it up but it does not seem to have faired too bad over 17K miles.
We now have a car lift in the workshop so it will soon go up and get a proper treatment.

The wheel arches do have a protective matting bonded into the glass to prevent stone damage but it would be a good idea to add the rubber paint. Previous kits I've built I treated with a product call 'Rubberoid' but it had gone from the market when I built my Ultima so mine does not have it. It does however have three coats of Stonechip.

Steve

[Storer]

Thanks for all the replies guys.

The idea of leaving the underside unprotected does not appeal to me. The powder coat looks to be at it's thinnest on the sheet metal of the underside of the floor pan and as I have a stone drive I think it will need all the extra protection it can get.

Steve
Your experience with the Ultima carries a lot of weight on this forum with the fact that you have owned the car for so long and put quite a few miles on it. I will take a good look into Hammerite Stonechip.

I do not discount using Rubbercoat or Isoflex Liquid Rubber as these may be better products that have only recently been released.

Adhesion to the alloy shouldn't be a problem as I already have some etching primer which I use in my businesses. I will giver the manufacturer a call to check compatibility with my chosen product.

Paul

[pilbeam_mp62]

Storer said:

I do not discount using Rubbercoat or Isoflex Liquid Rubber as these may be better products that have only recently been released.

Just one more thing to tell you about the Isoflex Liquid Rubber - you need to apply it with the
clip OFF the car, because the best way to do it is to just tip it out of the tin and smooth it around a bit till it finds a level - a bit like a floor screed.

It won't work very weill (IMO) if you try to paint it on with the clip vertically attached to the car.

Regards

[CMB123]

Hi

Sorry to chime in here. I am a bit of an Ultima lurker (still doing my homework before a potential plunge) and often frequent the Lotus side (ex-owner Esprit).
I know a number of people swear by POR15 for these underside applications and for Hight temp painting. I have used this on some of my bikes and it has faired much better than hammerite or powdercoat.

Cheers

CMB123

[CMB123]

Hi

Sorry to chime in here. I am a bit of an Ultima lurker (still doing my homework before a potential plunge) and often frequent the Lotus side (ex-owner Esprit).
I know a number of people swear by POR15 for these underside applications and for Hight temp painting. I have used this on some of my bikes and it has faired much better than hammerite or powdercoat.

Cheers

CMB123

[Steve_D]

CMB123 said:

Hi

Sorry to chime in here. I am a bit of an Ultima lurker (still doing my homework before a potential plunge) and often frequent the Lotus side (ex-owner Esprit).
I know a number of people swear by POR15 for these underside applications and for Hight temp painting. I have used this on some of my bikes and it has faired much better than hammerite or powdercoat.

Cheers

CMB123

I agree POR15 is better than Hamerite paint on hard surfaces.
What we are talking about here is something with flexibility to deal with 'gravel rash' on the underskin and inside the wheel arches.

IMHO POR15 is not right for this job.

Steve

[TangoGTR]

pilbeam_mp62 said:

This is the stuff I used on the inside of the rear wheel arches - Isoflex Liquid Rubber :-

Steve_D said:

On mine I used 'Hammerite Stonechip' aerosol to both coat the insides of panels and do the whole underside. Each time it goes for its MOT test I keep meaning to take a can along and touch it up but it does not seem to have faired too bad over 17K miles.
We now have a car lift in the workshop so it will soon go up and get a proper treatment.

The wheel arches do have a protective matting bonded into the glass to prevent stone damage but it would be a good idea to add the rubber paint. Previous kits I've built I treated with a product call 'Rubberoid' but it had gone from the market when I built my Ultima so mine does not have it. It does however have three coats of Stonechip.

Steve

Dragging this thread back up from a search, as looking to coat inside of front & rear clams. Have both Isoflex Liquid Rubber & Hammerite Stone chip.

Can I assume the isoflex is ok in wheel arches, including rear & not effected by heat of engine ? My thoughts were to use the Hammerite Stonechip for the clam area above engine. Does this cope OK with heat from engine ?

Edited by TangoGTR on Sunday 4th September 21:25

[Steve_D]

TangoGTR said:

.....Can I assume the isoflex is ok in wheel arches, including rear & not effected by heat of engine ? My thoughts were to use the Hammerite Stonechip for the clam area above engine. Does this cope OK with heat from engine ?

Stonechip has been in my engine bay for 7 years and is fine. I would bond the heat mat inside the rear clip first then spray the remaining areas. I bonded onto the stonechip but would not do it that way again...waste of paint if nothing else.

Isoflex would be good in the arches. The later clips have a protective pad bonded in but it is not a very large area and stones would ricochet around and hit almost any surface.

Steve

[TangoGTR]

Thanks Steve