91-95 rear fender liners - how to fix cracks?
10-23-2008, 02:41 AM
#31
Burning Brakes
sherwin williams auto paint suppliers have repair kits for plastic pannels like this if a decent one can be found i'm thinking thermal form abs plastic would be the ticket it can be done in a house oven and a small hand press mould would work fine i made canoe endcaps like this for yrs when i worked in the boat factory
10-23-2008, 11:32 PM
#33
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We have been working on a replacement but as of todate got nothing to do the job.
On my GTS I sprayed the inner fender with "bed liner" spray on stuff to act as a sound proofer.
Then I will add the front and rear splash shields from the pre 91 cars. The rear shield from the left side will fit the right side with a smal mod at the top of the shield.
Have not driven my car much but it appears to have done the job and for a lot less money.
On my GTS I sprayed the inner fender with "bed liner" spray on stuff to act as a sound proofer.
Then I will add the front and rear splash shields from the pre 91 cars. The rear shield from the left side will fit the right side with a smal mod at the top of the shield.
Have not driven my car much but it appears to have done the job and for a lot less money.
go to Walmart and get that puffy nylon stuff they use in pillows and artys fartsy stuff. Get a couplle of black garbage bags and smaller plastic bags and start stuffing them with various amounts of filler. The stuff teh bags up in the wheel archs and wheel wheels...spare tire area etc etc. Amazing what it does! The pillars aft of the doors are the worse! Next to nothing in weight and made a great improvement on my S4
10-24-2008, 10:01 AM
#34
Can someone post up a picture of these things?
I have a roll of 1/8 x 24" wide black polypro that I had custom made for a project years back. I only needed a 3rd of what I had to buy so the rest has been sitting on a shelf.
Is this part something that could be cut from a flat sheet?
I have a roll of 1/8 x 24" wide black polypro that I had custom made for a project years back. I only needed a 3rd of what I had to buy so the rest has been sitting on a shelf.
Is this part something that could be cut from a flat sheet?
10-25-2008, 05:15 PM
#37
Racer
I can reach in and just crumble mine with my hands they are so brittle.
Seems to me that the companies that mold bedliners should be able to mold these.
I thought about fiberglassing the liners in place. It would have to be done in at least two sections to be able to remove them.
Another crazy idea was Vycor, the adhesive backed rubber material used for flashing in construction.
But part of all of this is that some of us want to have our cars remain original, or as close as possible.
Greg
Seems to me that the companies that mold bedliners should be able to mold these.
I thought about fiberglassing the liners in place. It would have to be done in at least two sections to be able to remove them.
Another crazy idea was Vycor, the adhesive backed rubber material used for flashing in construction.
But part of all of this is that some of us want to have our cars remain original, or as close as possible.
Greg
10-25-2008, 05:49 PM
#38
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Nicole,
Your liner cracks would be easier to repair than mine were. You wouldn't believe the repairs I had to make to one of my liners strong again. This kind of repair worked for seven years on my '85S and two years on the S4 without problems. I use this technique to repair fender liners, rubber front spoilers, composite underbelly pans, and other parts that are not easily seen. I don't have pics but here's what I did.
1) Cut out two thin sheet metal "patches" that extend about 1-1/2 inches around all sides of the crack with the crack centered.
2) Clamp the two sheet metal pieces together and drill holes through both pieces simultaneously so the holes line up on both sheet metal pieces. Hole placement should be at least 3/4" from the edge of the crack/hole/weak spot.
3) Use a pencil to mark around edge of the metal pieces in place over the crack, marking the liner so you can line up the metal pieces when you go to put them on.
4) Take one of sheet metal pieces, put it into place on the liner, using the pencil marks to line it up.
5) Drill holes through the existing holes in the sheet metal that has been dummied into place and drill through the liner. You may want to clamp the sheet metal into place or do a temporary pop rivet to make sure the sheet metal patch doesn't shift while you're drilling the holes. If you use a pop rivit to hold it into place, use aluminum and fortify the other end on the other side of the liner with a larger washer so it doesn't break/crack your liner. You're right, old liners are fragile. I don't use large rivits, just enough to get the job done. I also, rivit in such a way that the "back side" protrudes where it can't be seen.
6) Drill out the temporary pop rivit and gob on a liberal coating of really thick Automotive Glue (cousin to Shoe Goo) on both pieces of sheet metal, put one pre-drilled sheet metal piece into place using the pre-drilled holes in the liner to line it up. Then, put two (aluminum) pop rivits into place (to assure alignment), with the other glue-gooed metal piece sandwiched on the other side of the liner, and once the sandwich is in place, "pop" the rivits into place. This will force out excess glue and the repair will be much stronger than the original liner material once it hardens. Plus the patch will not flex and break more liner as the glue not only secures but also cushions the two metal patches. Make sense? In review, the sandwich is as follows: sheet metal patch, goo glue, cracked liner, goo glue, and the backing sheet metal patch.
Also, to repair holes in the liner where the securing bolts have broken away the liner, the same technique can be used, after which you can drill a new hole through the metal patch.
It's fairly simple and the repair can be painted over or you can spray black sound deadner over the patch and it hides it well. For me, the worst part of this kind of repair was removing glue from my hands since I didn't use gloves. You want really agressive and very durable glue. If you can't get the very similar Automotive Glue from an auto parts store, I'm sure that Shoe Goo would work also.
For broken fins on non-metal undertrays, I've drilled tiny holes, then "laced" the broken piece back into place with tiny copper wire, then coated the repair with "Automotive Glue." If you don't wish to buy new or the part is NLA this technique works. Of course, new is always nicer although one works as well as the other.
I think it would be difficult to fabricate replacement liners from other material given all the curves, etc.
Harvey
Your liner cracks would be easier to repair than mine were. You wouldn't believe the repairs I had to make to one of my liners strong again. This kind of repair worked for seven years on my '85S and two years on the S4 without problems. I use this technique to repair fender liners, rubber front spoilers, composite underbelly pans, and other parts that are not easily seen. I don't have pics but here's what I did.
1) Cut out two thin sheet metal "patches" that extend about 1-1/2 inches around all sides of the crack with the crack centered.
2) Clamp the two sheet metal pieces together and drill holes through both pieces simultaneously so the holes line up on both sheet metal pieces. Hole placement should be at least 3/4" from the edge of the crack/hole/weak spot.
3) Use a pencil to mark around edge of the metal pieces in place over the crack, marking the liner so you can line up the metal pieces when you go to put them on.
4) Take one of sheet metal pieces, put it into place on the liner, using the pencil marks to line it up.
5) Drill holes through the existing holes in the sheet metal that has been dummied into place and drill through the liner. You may want to clamp the sheet metal into place or do a temporary pop rivet to make sure the sheet metal patch doesn't shift while you're drilling the holes. If you use a pop rivit to hold it into place, use aluminum and fortify the other end on the other side of the liner with a larger washer so it doesn't break/crack your liner. You're right, old liners are fragile. I don't use large rivits, just enough to get the job done. I also, rivit in such a way that the "back side" protrudes where it can't be seen.
6) Drill out the temporary pop rivit and gob on a liberal coating of really thick Automotive Glue (cousin to Shoe Goo) on both pieces of sheet metal, put one pre-drilled sheet metal piece into place using the pre-drilled holes in the liner to line it up. Then, put two (aluminum) pop rivits into place (to assure alignment), with the other glue-gooed metal piece sandwiched on the other side of the liner, and once the sandwich is in place, "pop" the rivits into place. This will force out excess glue and the repair will be much stronger than the original liner material once it hardens. Plus the patch will not flex and break more liner as the glue not only secures but also cushions the two metal patches. Make sense? In review, the sandwich is as follows: sheet metal patch, goo glue, cracked liner, goo glue, and the backing sheet metal patch.
Also, to repair holes in the liner where the securing bolts have broken away the liner, the same technique can be used, after which you can drill a new hole through the metal patch.
It's fairly simple and the repair can be painted over or you can spray black sound deadner over the patch and it hides it well. For me, the worst part of this kind of repair was removing glue from my hands since I didn't use gloves. You want really agressive and very durable glue. If you can't get the very similar Automotive Glue from an auto parts store, I'm sure that Shoe Goo would work also.
For broken fins on non-metal undertrays, I've drilled tiny holes, then "laced" the broken piece back into place with tiny copper wire, then coated the repair with "Automotive Glue." If you don't wish to buy new or the part is NLA this technique works. Of course, new is always nicer although one works as well as the other.
I think it would be difficult to fabricate replacement liners from other material given all the curves, etc.
Harvey
10-26-2008, 08:57 AM
#39
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+1, Harvey.
I've been doing this on various plastic bits, mounting tabs and so forth, for 40+ years. When the cracks are on edges, one can simply fold a single piece of sheet metal over the spot. Works well and lasts well. Less than elegant, but quite economical.
Not to mention the satisfaction of doing it rather than buying it - that secure feeling that you've defeated, or at least forestalled, the ravages of entropy, and may be able to do it again if necessary.
I've been doing this on various plastic bits, mounting tabs and so forth, for 40+ years. When the cracks are on edges, one can simply fold a single piece of sheet metal over the spot. Works well and lasts well. Less than elegant, but quite economical.
Not to mention the satisfaction of doing it rather than buying it - that secure feeling that you've defeated, or at least forestalled, the ravages of entropy, and may be able to do it again if necessary.
10-26-2008, 02:47 PM
#40
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Mine on the GTS are the same way. The problem with trying to fix the cracks is that the material that the fix is attached to just plain sucks!! As Greg said, I can literally reach back there and push on the plastic and it will break with ease.
Correct me if I'm wrong, but could we not come up with something like a fiberglass molded liner? I don't know too much about laying glass out, but I've seen it done at stereo shops, etc. Again, I don't claim to know **** from shinola on this, maybe I'm thinking it's easier than it really is???
Correct me if I'm wrong, but could we not come up with something like a fiberglass molded liner? I don't know too much about laying glass out, but I've seen it done at stereo shops, etc. Again, I don't claim to know **** from shinola on this, maybe I'm thinking it's easier than it really is???
10-26-2008, 06:00 PM
#41
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I reinstalled mine last night, so I can drive the car until I found the right solution. Of course, they cracked more during installation - it just can't be avoided.
The trouble with fiberglass would be that you could not install them in one piece - they have to flex quite a bit during installation. Ideally, there would be a front and a back piece, but then you'd have the challenge of keeping them sealed.
The trouble with fiberglass would be that you could not install them in one piece - they have to flex quite a bit during installation. Ideally, there would be a front and a back piece, but then you'd have the challenge of keeping them sealed.
10-26-2008, 10:44 PM
#43
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Herman - I think the GTS ones are still available - but at over $600 per side you end up with the same crappy material... a bit like the GTS intake tubes... what were they thinking....
How differently shaped are the rear wells from the fronts? - is there any possibility of adapting the front liners to the rear? - anyone ever checked this out? Adding the foam to the back of the front liner material would not be too hard...
Alan
How differently shaped are the rear wells from the fronts? - is there any possibility of adapting the front liners to the rear? - anyone ever checked this out? Adding the foam to the back of the front liner material would not be too hard...
Alan
10-27-2008, 09:52 AM
#44
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The GTS liners are all NLA.
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
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928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
10-27-2008, 11:38 AM
#45
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Thanks Roger - I would never have bought them anyway - The cost was high but its the material that convinces you this is a really bad idea...
Alan
Alan