Do you put the filler on the bear metal ( as I was always taught )
or do you put an etch primer on the car first then fill eg filler on the paint?
here's an interesting question about filler
Moderator: Bootsy
Re: here's an interesting question about filler
Why do metal bears need filler ?912uk wrote:Do you put the filler on the bear metal ( as I was always taught )
or do you put an etch primer on the car first then fill eg filler on the paint?
I know I shouldn't take the p155 Mark, but that one was too easy
James
1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster
Its not how fast you go, but how you go fast
1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster
Its not how fast you go, but how you go fast
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Graham
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Do not use a wash/etch primer then fill over it!,I used to use a yellow wash primer but just to stop the metal tarnishing,I would then clean it all off then key up and apply bondo!
I always go for bare metal,if you can try to get some aluminium filler,it is a great subsitute for lead and hard as nails,a pain to rub down,but perfect for shuts/edges because its so tough.
Modern quality fillers are really good,lead is great but no really practical in certain areas,I stripped a 356 door that had no filler in it,a bottom skin had been fitted and they had leaded the whole thing up,1/4 inch thick in places,it weighed a ton,the panel was distorted to hell,a real mess!!
the whole car is the same!!
I always go for bare metal,if you can try to get some aluminium filler,it is a great subsitute for lead and hard as nails,a pain to rub down,but perfect for shuts/edges because its so tough.
Modern quality fillers are really good,lead is great but no really practical in certain areas,I stripped a 356 door that had no filler in it,a bottom skin had been fitted and they had leaded the whole thing up,1/4 inch thick in places,it weighed a ton,the panel was distorted to hell,a real mess!!
the whole car is the same!!
1985 MZ Simson/KH 125 Sprint bike
1302s one family owner
1963 AMC 660 Classic
1957 Peugeot TC4 race bike
Sadly gone:
74' 914/4 2.0
68' SWB 911
1302s one family owner
1963 AMC 660 Classic
1957 Peugeot TC4 race bike
Sadly gone:
74' 914/4 2.0
68' SWB 911
filler
both are acceptable.
if you etch prime or epoxy prime as a base the metal will be sealed against rusting, you can then use filler at your leisure. scuff the surface with some 80 grit
if you fill bare metal you have to spray sealer or epoxy fairly quickly to prevent moisture from flash rusting, you can't use a metal conditioner on the filler.
each has its advantages, your choice
bob
if you etch prime or epoxy prime as a base the metal will be sealed against rusting, you can then use filler at your leisure. scuff the surface with some 80 grit
if you fill bare metal you have to spray sealer or epoxy fairly quickly to prevent moisture from flash rusting, you can't use a metal conditioner on the filler.
each has its advantages, your choice
bob
bob
1972 911E
in over my head
1972 911E
in over my head
Hello all.
Caveat: I did research this some years ago, so this may be a little out of date....
The problem is that polyester fillers are all readily permeable to water vapour.
Epoxy fillers much less so: and a thick enough coat of solvent free pure epoxy ideally, or epoxy solvented paint with high enough build will be as near to impermeable as we need..
Most etch primers applied at normal thickness are still permeable enough to allow rusting..only after top coating does the film attain sufficint thickenss .
Interestingly enough non-silicone wax polishes can be a significant help.
In conclusion, solvent free epoxy based systems from the metal up are the currently best for adhesion, rustproofing, and mechanical strength.
An excellent hard surface finish can be obtained, ready for paint with minimal or no surfacer, and there is no shrinkage even with deep filling.
They are more costly, somewhat toxic, fiddly to use unless you are very familiar with the process, and slower.
I like it....have used masses of it, but have yet to find anyone in the trade who agrees with me!
Back to work now..
Kind regards
David
Caveat: I did research this some years ago, so this may be a little out of date....
The problem is that polyester fillers are all readily permeable to water vapour.
Epoxy fillers much less so: and a thick enough coat of solvent free pure epoxy ideally, or epoxy solvented paint with high enough build will be as near to impermeable as we need..
Most etch primers applied at normal thickness are still permeable enough to allow rusting..only after top coating does the film attain sufficint thickenss .
Interestingly enough non-silicone wax polishes can be a significant help.
In conclusion, solvent free epoxy based systems from the metal up are the currently best for adhesion, rustproofing, and mechanical strength.
An excellent hard surface finish can be obtained, ready for paint with minimal or no surfacer, and there is no shrinkage even with deep filling.
They are more costly, somewhat toxic, fiddly to use unless you are very familiar with the process, and slower.
I like it....have used masses of it, but have yet to find anyone in the trade who agrees with me!
Back to work now..
Kind regards
David
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Barry
- Nurse, I think I need some assistance
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I've never heard of anyone going over etch primer, and can't see why you would want / need to. I use DC Coachworks as my guide as they put out as close to perfection as I've ever seen (and regularly work on 1/2 - 1 1/2 million pound cars), and they fill direct to metal, as does everyone else I know in the trade. The bottom line is that filler has been developed to go straight to metal, and if you think of the practicalities off going over etch: you could never do it without then rubbing through an area of etch around the filler anyway.
After cleaning up the car, hit it with the etch primer. Then at your leisure just sand back any areas for filling back to bare again and fill away. It's only a wash primer anyway, so has very little 'body' to sand through. Once finished, you can always flash another coat of etch on.
This all assumes that you are likely to be taking a load of leisure time on the filling, and that it's going to take many weeks or several months.
If you are going directly from cleaning back to bare metal straight onto filling, and you've got a bone-dry workshop (preferably de-humidified), you won't need to worry about etching until the filling is done. As has been mentioned, all of the fillers, poly's and primers are porous anyway, so you are better off concentrating on keeping humidiity to an absolute minimum.
Just before each of the next layers (filling / spray polyester if you need it, priming and finally the topcoat) the car needs to be warmed up as well as dehumidified (preferably overnight if you are DIY'ing it) to drive out as much moisture as possible.
One thing: if you go down the spray polyester route to finally fair in large panels with ripples too fine to fill, the poly does not like:
a) Being feathered out through part of a panel as it 'contours'* so you need to go right to the edge of a panel, and try not to rub back through to metal. If you do just use another dose of poly to blow it back in, and ...
b) It reacts to etch primer, but doesn't need to go over it, and doesn't need etch over it either.
*Contouring: where a filler or primer sinks at a different rate to the surrounding areas, leaving a visible contour line in the surface of the topcoat. Can sometimes be flatted and machined once settled (six months or so).
BTW, I think lead being used as an actual filler has had it's day, as the heat required to melt bodysolder (around 200DC + ) is plenty enough to distort large flat panels. It is still useful though around doorgap type areas though, if the correct precautions are used regarding heat spread and flux rinsing. On one of the Contour Autocraft course, this chap had done a lovely repair to the base of a Miget door, albeit a lapped joint which was then plug welded. Nevertheless, it looked very good. Proudly they gathered us around to watch the mystical powers of lead loading being demonstrated.
Before our very eyes, we watched in amazment as this perfectly nice repair was reduced to a blackened, distorted mess, complete with flux enbedded all of the way through his lap join. Just to add insult to injury, it was literally right at the end of the course, so he had no time to try to put it right
. A real shame, and simply the wrong place to use the prrocess.
After cleaning up the car, hit it with the etch primer. Then at your leisure just sand back any areas for filling back to bare again and fill away. It's only a wash primer anyway, so has very little 'body' to sand through. Once finished, you can always flash another coat of etch on.
This all assumes that you are likely to be taking a load of leisure time on the filling, and that it's going to take many weeks or several months.
If you are going directly from cleaning back to bare metal straight onto filling, and you've got a bone-dry workshop (preferably de-humidified), you won't need to worry about etching until the filling is done. As has been mentioned, all of the fillers, poly's and primers are porous anyway, so you are better off concentrating on keeping humidiity to an absolute minimum.
Just before each of the next layers (filling / spray polyester if you need it, priming and finally the topcoat) the car needs to be warmed up as well as dehumidified (preferably overnight if you are DIY'ing it) to drive out as much moisture as possible.
One thing: if you go down the spray polyester route to finally fair in large panels with ripples too fine to fill, the poly does not like:
a) Being feathered out through part of a panel as it 'contours'* so you need to go right to the edge of a panel, and try not to rub back through to metal. If you do just use another dose of poly to blow it back in, and ...
b) It reacts to etch primer, but doesn't need to go over it, and doesn't need etch over it either.
*Contouring: where a filler or primer sinks at a different rate to the surrounding areas, leaving a visible contour line in the surface of the topcoat. Can sometimes be flatted and machined once settled (six months or so).
BTW, I think lead being used as an actual filler has had it's day, as the heat required to melt bodysolder (around 200DC + ) is plenty enough to distort large flat panels. It is still useful though around doorgap type areas though, if the correct precautions are used regarding heat spread and flux rinsing. On one of the Contour Autocraft course, this chap had done a lovely repair to the base of a Miget door, albeit a lapped joint which was then plug welded. Nevertheless, it looked very good. Proudly they gathered us around to watch the mystical powers of lead loading being demonstrated.
Before our very eyes, we watched in amazment as this perfectly nice repair was reduced to a blackened, distorted mess, complete with flux enbedded all of the way through his lap join. Just to add insult to injury, it was literally right at the end of the course, so he had no time to try to put it right
. A real shame, and simply the wrong place to use the prrocess.DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
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Graham
- DDK forever
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I agree 100% with what Barry has said,the thing is because I do this for a living the car does not sit for weeks in bare metal,its done very quickly,in a dry enviroment,if your doing it at home,then flashing over with a primer to protect the metal is a good idea,the attack it in stages,I also like to do a section at a time,say 1/4 of the car shell,and not get carried away and miss little bits because your hopping from one bit to another,the key to great paint is the prep!
1985 MZ Simson/KH 125 Sprint bike
1302s one family owner
1963 AMC 660 Classic
1957 Peugeot TC4 race bike
Sadly gone:
74' 914/4 2.0
68' SWB 911
1302s one family owner
1963 AMC 660 Classic
1957 Peugeot TC4 race bike
Sadly gone:
74' 914/4 2.0
68' SWB 911
i stand corrected
after reading the above posts, i did a little research. and found this : http://www.autobodystore.com/filler_&_epoxy.shtml
pretty extreme test, but bare metal application is superior.
the question remains is it necessary.
i have always admired barry's work from afar, acknowledge his skill
and most importantly value his opinion
i did not be controversial with my very first post!
pretty extreme test, but bare metal application is superior.
the question remains is it necessary.
i have always admired barry's work from afar, acknowledge his skill
and most importantly value his opinion
i did not be controversial with my very first post!
bob
1972 911E
in over my head
1972 911E
in over my head
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Barry
- Nurse, I think I need some assistance
- Posts: 4319
- Joined: Tue Aug 24, 2004 8:50 pm
- Location: East Sussex
Aww, shucks 
.You're O.K. Bob, it's always good to float these views around as I don't suppose any of us would claim to know everything. After all, it wasn't that long ago that lead loading was King, and plastic filler was seen as a bodge.
Things keep moving on, and new views coming to the fore often helps drive things on, or at least make people think about why they do something, rather than just doing it out of habit.
Welcome to the forum
.DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
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Barry
- Nurse, I think I need some assistance
- Posts: 4319
- Joined: Tue Aug 24, 2004 8:50 pm
- Location: East Sussex
BTW, if someone had asked about that about test, I'd have been able to give them a good idea from my experience: I use Wurth metal filler spreaders (which are basically spring steel with a plastic grip).
The degree to which the filler adheres to these is truly amazing, and if the filler layer is fairly thin, you can bend the spreader / spatula through quite a bend before the filler bond fails.
The degree to which the filler adheres to these is truly amazing, and if the filler layer is fairly thin, you can bend the spreader / spatula through quite a bend before the filler bond fails.
DDK Member1243 07741 273865. Now booking Spring '24. Home of the RY Austin 7 Trophy's
All filling on a restoration should be done onto bright clean steel, however small amounts of stopper can be applied over paint to do patch repairs, say over minor car park door type marks that dont warrant the panel being stripped to put right.
To keep rust at bay on a long turm project, a wipe over with jenolite, and then dried off with a clean cloth will stop flash rusting, but clean the area with fine paper before continuing.
A spread of metal filler (UPOL D or equiverlent) over a lap joint will seal it and stop rust getting into the seam until you have time to finish the filling.
If you are doing it as a home resto, with the intension of getting someone else to finish and paint it, get them on board early on and work with products they recomend, and follow their advice, on processes.
UNLESS you are very good at bodywork, expect to pay them to do a final skim and flat down on all your repairs!
And finally remember there will be a time when all your hard work seams worthwhile, but its unlikly to be when you are knee deep in dust
To keep rust at bay on a long turm project, a wipe over with jenolite, and then dried off with a clean cloth will stop flash rusting, but clean the area with fine paper before continuing.
A spread of metal filler (UPOL D or equiverlent) over a lap joint will seal it and stop rust getting into the seam until you have time to finish the filling.
If you are doing it as a home resto, with the intension of getting someone else to finish and paint it, get them on board early on and work with products they recomend, and follow their advice, on processes.
UNLESS you are very good at bodywork, expect to pay them to do a final skim and flat down on all your repairs!
And finally remember there will be a time when all your hard work seams worthwhile, but its unlikly to be when you are knee deep in dust
Fenn Lane Motorsport 01455 213998
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1965 porsche 912
Interesting reading Cheers guys
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the etch primer has started to in places come though on the car.. poss due to some damp from the car port on the car over the years I am not worried as the etch primer was only ever a dust coat to keep it all at bay..
I will strip the paint off well wipe it off with a cloth and thinners to show the metal again and then i can start to fill it.. it's a shame it's coming on for winter I am very up set about this as I am about to start on the filler work and this will be difficult with all this damp weather I might have to hold off till next year and get on with other stuff or move the car to some where warmer to do the work.. I hope with in the month to be sealing and painting the underside of the Pre A. That will feel great progress!!!!
jenolite not ever been a fan of this... I rust rust.co.uk stuff and Hammerite Rust cure I think they are both the same infact I think the Rust cure is just a watered down version of it. This stuff works very well I only know this as this has been all I have used I had an apprentise with his boy racer Nova and he did all this repair work and then it come though useing jenolite I said to use Rust cure and it did the trick..
I have a small bottle I have tried it but it's free if you want it...
and your right I am knee deep in dust at the mo and underseal and it's not looking like I am going to be drving it any time soon I need a pick me up
I keep staring at the goal and this is the goal..same colour same tyres but painted cream and green wheels for me.
I will strip the paint off well wipe it off with a cloth and thinners to show the metal again and then i can start to fill it.. it's a shame it's coming on for winter I am very up set about this as I am about to start on the filler work and this will be difficult with all this damp weather I might have to hold off till next year and get on with other stuff or move the car to some where warmer to do the work..
I hope with in the month to be sealing and painting the underside of the Pre A. That will feel great progress!!!! jenolite not ever been a fan of this... I rust rust.co.uk stuff and Hammerite Rust cure I think they are both the same infact I think the Rust cure is just a watered down version of it. This stuff works very well I only know this as this has been all I have used I had an apprentise with his boy racer Nova and he did all this repair work and then it come though useing jenolite I said to use Rust cure and it did the trick..
I have a small bottle I have tried it but it's free if you want it...
and your right I am knee deep in dust at the mo and underseal and it's not looking like I am going to be drving it any time soon
I need a pick me up I keep staring at the goal and this is the goal..same colour same tyres but painted cream and green wheels for me.