Sealant?

[kikets]

Hi!!

It's time to rivet all the panels, but I have some questions about how did you guys applied the sealant.

Did you applied sealant on boths sides of the chassis holes? ("copckit/outside")

Also, did you rivet just after aplying the sealant?

not really "high tech" questions... but would great to know!

Thanks!

[Steve_D]

I applied a healthy bead of sealant down the line of the rivet holes so that it could spread over the whole contact area.
Place your panel and hold in place with skin pins. Put all the rivets in their holes so that the panel cannot get out of line as you rivet preventing you from getting the last ones in. Dive around with your air rivet gun (you do have an air riveter don't you?).
Once all the rivets are popped start wiping away the sealant that has oozed out using paper towels and brake cleaner.

Don't forget to use your rubber gloves as the sealant is impossible to get of your hands...you have to wait until it wears away.

Steve

[Pb3]

I put the sealant down, avoiding the holes. You are trying to bond the panel to the chassis, if you put it over the holes you will most likely push the sealant into the hole with the rivit thus effectively wasting it. One you do the panels that have to be formed around the round section keep the sealant below the line of rivits. If it is above it will make the forming process very difficult as the sealant acts as a cushion when you hit it! You also want to avoid sealant being pushed through the rivit holes and in some cases even the centre of the rivit, it just makes more mess to clear up afterwards.

[kikets]

yess!! I have an air riveter!!

Thank you!!

[ezakimak]

is the sealant a structural glue? or something else, could it be used without the riverts.
I would think that a good glue would be stronger than riverts

thanks for the tip about being below the curved top pannel, thats a good tip to file away for latter.

[Pb3]

I found unleaded very effective at removing sealant, something less dangerous is metholated spirit.

[738 driver]

A silicone only really produces a sealant/gasket to prevent ingress (although the factory do imply it bonds the skins to the powder coating) its not 'body adhesive' which is several times stronger and usually involves an etch-primer/activator coat. Sikaflex is sort off half-way-house stuff but couldn't really be classed as structural when bonded to powder coating!
As Steve I ran down the rivet line to help reduce chassis member ingress.
Petrolium based products will swell/soften/remove silicone sealers and also rot silicone hose over a few hours, cured body sealer is resistant to most chemicals. HTH

Edited by 738 driver on Thursday 1st October 10:04

[k wright]

You should fit the panel, temporarily fasten it with Kleco pins and then bend the top of the panel around the chassis tube. After this is done you can remove it and apply sealant and rivet it in.

[Crazy of Cookham]

WD40 is very good at removing sealant. Not sure if recognised hand treatment

[Steve_D]

738 driver said:

A silicone only really produces a sealant/gasket to prevent ingress (although the factory do imply it bonds the skins to the powder coating) its not 'body adhesive' which is several times stronger and usually involves an etch-primer/activator coat. Sikaflex is sort off half-way-house stuff but couldn't really be classed as structural when bonded to powder coating!
As Steve I ran down the rivet line to help reduce chassis member ingress.
Petrolium based products will swell/soften/remove silicone sealers and also rot silicone hose over a few hours, cured body sealer is resistant to most chemicals. HTH

Edited by 738 driver on Thursday 1st October 10:04

The sealant used is not a silicone it is a polysulphide. Sikaflex is a common trade name for polysulphide. It is intended to be structural but as you say is only as strong as the surface it is bonding to.

The skin rolled around the chassis rail should be formed first then bonded and riveted with sealant round the roll otherwise it will vibrate.

Another reason for running the sealant down the line of the rivets is so that sealant goes ito and semi seals the rivet hole and more importantly comes up under the rivet head and seals that. For those who have driven an Ultima without carpet on the side and top of the side pod will know that you keep catching the hairs on the underside of your forearm under the heads of the rivets.

Steve

[738 driver]

Sikaflex is indeed 'touted' as structural bonding adhesive but.........when guys start using it to bond screens (part of the structure on modern motors) and are fitting back quarter panels with it which later break loose, there exists huge over-expectation of its ability..it's is not true 'bonded body adhesive'. There are several car models which have stress members fully bonded and usually the manufacturer has an approved product......normally two-pack basis.
A few years back the owner of a large local repairer faced several months porridge due to one of his lads using a Sikka-type adhesive inappropriately....a policyholder and insurer where going after him full tilt for what was seemingly a common occurance. It changed the way large repairers dealt with any bonding processes during a repair.
The factory must approve their supplied sealants but they really could not ever be described as 'structural bonding' its merely a sealant in this instance.

[Steve_D]

738 driver said:

Sikaflex is indeed 'touted' as structural bonding adhesive but.........when guys start using it to bond screens (part of the structure on modern motors) and are fitting back quarter panels with it which later break loose, there exists huge over-expectation of its ability..it's is not true 'bonded body adhesive'. There are several car models which have stress members fully bonded and usually the manufacturer has an approved product......normally two-pack basis.
A few years back the owner of a large local repairer faced several months porridge due to one of his lads using a Sikka-type adhesive inappropriately....a policyholder and insurer where going after him full tilt for what was seemingly a common occurance. It changed the way large repairers dealt with any bonding processes during a repair.
The factory must approve their supplied sealants but they really could not ever be described as 'structural bonding' its merely a sealant in this instance.

In fairness to Sika they produce dozens if not hundreds of different types and grades with uses ranging from sealants to bonding including types specificly for windscreen and structural bonding.

Steve

[pilbeam_mp62]

Two builders, whose methods and opinions I respect, have said that you bend the panel round the tube BEFORE bonding and rivetting.

There is, presumably, more than one way to skin a cat (or should that be - a car)

I bonded and rivetted the panel and THEN whacked it with a rubber-headed hammer to form the curve.

Regards
Kelvin

[Stig]

Steve_D said:

738 driver said:

Sikaflex is indeed 'touted' as structural bonding adhesive but.........when guys start using it to bond screens (part of the structure on modern motors) and are fitting back quarter panels with it which later break loose, there exists huge over-expectation of its ability..it's is not true 'bonded body adhesive'. There are several car models which have stress members fully bonded and usually the manufacturer has an approved product......normally two-pack basis.
A few years back the owner of a large local repairer faced several months porridge due to one of his lads using a Sikka-type adhesive inappropriately....a policyholder and insurer where going after him full tilt for what was seemingly a common occurance. It changed the way large repairers dealt with any bonding processes during a repair.
The factory must approve their supplied sealants but they really could not ever be described as 'structural bonding' its merely a sealant in this instance.

In fairness to Sika they produce dozens if not hundreds of different types and grades with uses ranging from sealants to bonding including types specificly for windscreen and structural bonding.

Steve

Worth noting that the factory supply Wurth Bond'n'Seal - not Sika.

[738 driver]

Stig said:

Steve_D said:

738 driver said:

Sikaflex is indeed 'touted' as structural bonding adhesive but.........when guys start using it to bond screens (part of the structure on modern motors) and are fitting back quarter panels with it which later break loose, there exists huge over-expectation of its ability..it's is not true 'bonded body adhesive'. There are several car models which have stress members fully bonded and usually the manufacturer has an approved product......normally two-pack basis.
A few years back the owner of a large local repairer faced several months porridge due to one of his lads using a Sikka-type adhesive inappropriately....a policyholder and insurer where going after him full tilt for what was seemingly a common occurance. It changed the way large repairers dealt with any bonding processes during a repair.
The factory must approve their supplied sealants but they really could not ever be described as 'structural bonding' its merely a sealant in this instance.

In fairness to Sika they produce dozens if not hundreds of different types and grades with uses ranging from sealants to bonding including types specificly for windscreen and structural bonding.

Steve

Worth noting that the factory supply Wurth Bond'n'Seal - not Sika.

WURTH................hmm up market stuff price wise but their extremely tasty lady rep was 'well wurth it'!!

[Gulf -LS2]

mr w !!!! behave, especially at your age

[738 driver]

At least I dont lie about it !