Fabricating a cowel panel cover
#34
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There are two more versions of the Shell Sticker that I see in this thread--more than I have been able to see in my thread about these or that I have seen elsewhere. One is on Bruce's cowl cover and it's difference is in having a border around it. The other one is on the airbox in an early 928 with the partial cover and it is the three-line version, but is black on white with a yellow border.
I have studied these cowls quite a bit and have reached some conclusions about them that are probably obvious to the rest of you. One is that the purpose of the cowl cover is to provide some protection for the stuff inside the cowl area from the elements, particularly the water. Too, it is only the water that comes into that area from off the windshield and in back of the hood. It seems to be designed to drain that water foreward and both left and right away from the stuff that in in the cowl area. That, of course, was pointed out in this thread already.
However, I see a design flaw in this cover; and that is that the water coming in from the back of the hood and draining down toward the cowl area has to pass the gap between the cowl cover and the narrow metal cowl strip just below the windshield. There is no seal there for the water to pass over, so it appears that much of the water will simply drain between those components; and then the ledge or flange below there which slips into the three metal clips to hold the back up is not really designed to drain water, and in fact has the center area slightly recessed from the outer ends so that water is likely to puddle there.
Someone here is right that this cowl cover is a complex design.
Of the two covers that I took out of my cars to study, one is in pretty good shape but the other is in bad shape. What I decided to do was to try to correct the flimsy nature of this cover and make one that is stiff as a board. So, that is what I am doing--making myself one out of that--wood, and some other stuff that I had laying around in the shop. When some glue sets up and I do a little more trimming I'll post a picture of it.
I wonder what ever happend to the aluminum one the OP was trying to make.
Jerry Feather
I have studied these cowls quite a bit and have reached some conclusions about them that are probably obvious to the rest of you. One is that the purpose of the cowl cover is to provide some protection for the stuff inside the cowl area from the elements, particularly the water. Too, it is only the water that comes into that area from off the windshield and in back of the hood. It seems to be designed to drain that water foreward and both left and right away from the stuff that in in the cowl area. That, of course, was pointed out in this thread already.
However, I see a design flaw in this cover; and that is that the water coming in from the back of the hood and draining down toward the cowl area has to pass the gap between the cowl cover and the narrow metal cowl strip just below the windshield. There is no seal there for the water to pass over, so it appears that much of the water will simply drain between those components; and then the ledge or flange below there which slips into the three metal clips to hold the back up is not really designed to drain water, and in fact has the center area slightly recessed from the outer ends so that water is likely to puddle there.
Someone here is right that this cowl cover is a complex design.
Of the two covers that I took out of my cars to study, one is in pretty good shape but the other is in bad shape. What I decided to do was to try to correct the flimsy nature of this cover and make one that is stiff as a board. So, that is what I am doing--making myself one out of that--wood, and some other stuff that I had laying around in the shop. When some glue sets up and I do a little more trimming I'll post a picture of it.
I wonder what ever happend to the aluminum one the OP was trying to make.
Jerry Feather
Last edited by Jerry Feather; 01-22-2012 at 01:08 PM. Reason: typos
#35
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I'll bet you thought I was just kidding. Well, here it is in all of its minimal glory.
I still have to do some trimming and cut out the two openings plus cut out the front corners for the plumbing and wiring, Then all I have to do is figure out how to mount it.
I know that it doesn't look like much right now, but when I paint it black and maybe give it the Tony77 speckled finish with some undercoat, I'll bet you will not be able to tell it from the original. I'll have to wait for the sticker since I don't have that in the works right yet; or I might just get one from the guy on eBay in UK.
Pretty neat, Huh?
Jerry Feather
I still have to do some trimming and cut out the two openings plus cut out the front corners for the plumbing and wiring, Then all I have to do is figure out how to mount it.
I know that it doesn't look like much right now, but when I paint it black and maybe give it the Tony77 speckled finish with some undercoat, I'll bet you will not be able to tell it from the original. I'll have to wait for the sticker since I don't have that in the works right yet; or I might just get one from the guy on eBay in UK.
Pretty neat, Huh?
Jerry Feather
#38
Race Car
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I....did NOT....see that coming....
Well, what the heck looks better than the factory fuse panel cover....
FIngers crossed that IMo0o is on the right track...
Well, what the heck looks better than the factory fuse panel cover....
FIngers crossed that IMo0o is on the right track...
#40
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That's a real good question. With it, I, too, wonder if the early cars with the partial cover had all three clips for the cover in the back. I also still wonder how long the early short version was used; or when did the full length cover come in, and what did it look like?
Jerry Feather
Jerry Feather
#41
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I guess I also wonder how the OB guys before the Hi intensity washer system would like a full length cowl cover that didn't have the provision for the bottle cutout; in other words the driver's end looks just like the other end (and that kind of cover would work with the RHD cars, also without the washer bottle cutout).
For that matter, I wonder how the GTS guys would like such a cowl cover, especially if it looked a lot like the original except for the absence of a place to cut the washer bottle hole.
(I don't mean out of wood.)
Jerry Feather
For that matter, I wonder how the GTS guys would like such a cowl cover, especially if it looked a lot like the original except for the absence of a place to cut the washer bottle hole.
(I don't mean out of wood.)
Jerry Feather
#42
Rest in Peace
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I guess I also wonder how the OB guys before the Hi intensity washer system would like a full length cowl cover that didn't have the provision for the bottle cutout; in other words the driver's end looks just like the other end (and that kind of cover would work with the RHD cars, also without the washer bottle cutout).
For that matter, I wonder how the GTS guys would like such a cowl cover, especially if it looked a lot like the original except for the absence of a place to cut the washer bottle hole.
(I don't mean out of wood.)
Jerry Feather
For that matter, I wonder how the GTS guys would like such a cowl cover, especially if it looked a lot like the original except for the absence of a place to cut the washer bottle hole.
(I don't mean out of wood.)
Jerry Feather
#43
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Thanks for the responses about my cowl cover. Of course it is a spoof! Not the existense of the supposed cover made out of wood that I showed, but the fact that I would try to put that in the car.
I had thought I might get a rise out of more of you about this and perhaps stimulate some more feedback about the history of these cowl liners and maybe about the Shell Stickers they had on or near them.
Imo000 is close to right about his guess about what the wooden cover really is. However, true to one of my natures it is not for fiberglass but is in fact a form to vacu-form ABS plastic into the desired shape to replicate these covers, or one version of them.
I was challenged earlier in this thread about a month ago to take this on as a project, I think, and I was also challenged by the suggestion that they cannot be reproduced for less tha a hundred bucks. Depending on how much it actually costs to have these formed by my plastics guy (since I don't have a vacuum table up and going at this point) I think they might have been right about the cost, However, in order to try to minimize the forming cost I have made five of these forms, or am nearly finished making them, and he will be able to form 4 of them at a time.
The form shown above is a fair replication of the original out of my S4. The center hump is a little narrower, but the spacing of the fins is pretty close. I am also changing the rear ledge that goes into the three clips both to stiffen it up some and to provide for a closed cell foam seal that I plan to put on these in order to eliminate what I think is the design flaw in these covers. I hope to channel the water over the back edge and into the drainage aspec of the cover to the left and right front. I am also making the cut-outs for the hoses and wires slightly smaller, and I hope that doesn't cause a problem with installation.
However, out of the five forms I am making I have made two for the washer bottle cut-out and two without any provision for it. Those second two are the same left and right so the GTS guys and the early car guys without the bottle wont have to have a cover with the cut-out provision but that is not cut out. The provision will simply not be there in at least half of these that get formed.
Finally, for some odd reason I felt the need to try to sort of replicate what I think is the first version of this cover that provided for the washer bottle and that I think came out with the washer provision, maybe with the S3 cars. Mine is not as accurate a replication of that cover as the first is of the S4, but it has similar little raised flat areas in the back corners and the cut-out for the bottle is a little larger and without the raised "fence" around part of it.
There may not be much interest in this third version, but if not I can either leave it out of production or I may even form a few of them and then change that form to perhaps have the washer bottle opening at the other end like for the RHD cars. That may make a lot more sense, now that I think about it.
I think that four of these can be formed at a time in the vacuum table using half a sheet of plastic. I think I am going to make these out of .040 ABS and these should finish out at least .030, except perhaps inside the air vent provision. If that part comes out too thin I think I can glue a stiffener on the back of it underneath to help keep it in shape in service. I have seen so many installed in pictures that are deformed in this area that it concerns me.
Depending on the cost of that actual forming and of the plastic I hope to make these available at around $60 each plus likely about $15 for domestic shipping. With the stickers if I get them done that will possibly add about another $5. I'll be posting the final listing for these when they are done in my Vendor handle. This is not an offer to sell at this point.
Jerry Feather
I had thought I might get a rise out of more of you about this and perhaps stimulate some more feedback about the history of these cowl liners and maybe about the Shell Stickers they had on or near them.
Imo000 is close to right about his guess about what the wooden cover really is. However, true to one of my natures it is not for fiberglass but is in fact a form to vacu-form ABS plastic into the desired shape to replicate these covers, or one version of them.
I was challenged earlier in this thread about a month ago to take this on as a project, I think, and I was also challenged by the suggestion that they cannot be reproduced for less tha a hundred bucks. Depending on how much it actually costs to have these formed by my plastics guy (since I don't have a vacuum table up and going at this point) I think they might have been right about the cost, However, in order to try to minimize the forming cost I have made five of these forms, or am nearly finished making them, and he will be able to form 4 of them at a time.
The form shown above is a fair replication of the original out of my S4. The center hump is a little narrower, but the spacing of the fins is pretty close. I am also changing the rear ledge that goes into the three clips both to stiffen it up some and to provide for a closed cell foam seal that I plan to put on these in order to eliminate what I think is the design flaw in these covers. I hope to channel the water over the back edge and into the drainage aspec of the cover to the left and right front. I am also making the cut-outs for the hoses and wires slightly smaller, and I hope that doesn't cause a problem with installation.
However, out of the five forms I am making I have made two for the washer bottle cut-out and two without any provision for it. Those second two are the same left and right so the GTS guys and the early car guys without the bottle wont have to have a cover with the cut-out provision but that is not cut out. The provision will simply not be there in at least half of these that get formed.
Finally, for some odd reason I felt the need to try to sort of replicate what I think is the first version of this cover that provided for the washer bottle and that I think came out with the washer provision, maybe with the S3 cars. Mine is not as accurate a replication of that cover as the first is of the S4, but it has similar little raised flat areas in the back corners and the cut-out for the bottle is a little larger and without the raised "fence" around part of it.
There may not be much interest in this third version, but if not I can either leave it out of production or I may even form a few of them and then change that form to perhaps have the washer bottle opening at the other end like for the RHD cars. That may make a lot more sense, now that I think about it.
I think that four of these can be formed at a time in the vacuum table using half a sheet of plastic. I think I am going to make these out of .040 ABS and these should finish out at least .030, except perhaps inside the air vent provision. If that part comes out too thin I think I can glue a stiffener on the back of it underneath to help keep it in shape in service. I have seen so many installed in pictures that are deformed in this area that it concerns me.
Depending on the cost of that actual forming and of the plastic I hope to make these available at around $60 each plus likely about $15 for domestic shipping. With the stickers if I get them done that will possibly add about another $5. I'll be posting the final listing for these when they are done in my Vendor handle. This is not an offer to sell at this point.
Jerry Feather
#44
928 Collector
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That is - I have to say - BEAUTIFUL WORK
... You don't need all that detail, and in some cases it may be undesirable. I'd make it flat (no water channels) and change the holes (all you need is a small hole for the windshield washer cables, not that wide or the square one).
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I'll bet you thought I was just kidding. Well, here it is in all of its minimal glory.
I still have to do some trimming and cut out the two openings plus cut out the front corners for the plumbing and wiring, Then all I have to do is figure out how to mount it.
I know that it doesn't look like much right now, but when I paint it black and maybe give it the Tony77 speckled finish with some undercoat, I'll bet you will not be able to tell it from the original. I'll have to wait for the sticker since I don't have that in the works right yet; or I might just get one from the guy on eBay in UK.
Pretty neat, Huh?
Jerry Feather
I still have to do some trimming and cut out the two openings plus cut out the front corners for the plumbing and wiring, Then all I have to do is figure out how to mount it.
I know that it doesn't look like much right now, but when I paint it black and maybe give it the Tony77 speckled finish with some undercoat, I'll bet you will not be able to tell it from the original. I'll have to wait for the sticker since I don't have that in the works right yet; or I might just get one from the guy on eBay in UK.
Pretty neat, Huh?
Jerry Feather
#45
Electron Wrangler
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Jerry - wow - that should look great when done. Is that plastic choice heavier than the currently available cowls from Porsche?, different material properties?
I think making the cable/tube cut outs a little smaller is a great idea - ditto better sealing at the back
Assume you will keep the lip at the front somehow - can you do the U shaped lip at the front? I can see that being hard to fabricate along that curve?
Look great so far! Jerry - all it takes is a challenge thrown down huh?
Alan
PS Don't forget to finish the fender liners first - I'm ready to buy a GTS set....!!
I think making the cable/tube cut outs a little smaller is a great idea - ditto better sealing at the back
Assume you will keep the lip at the front somehow - can you do the U shaped lip at the front? I can see that being hard to fabricate along that curve?
Look great so far! Jerry - all it takes is a challenge thrown down huh?
Alan
PS Don't forget to finish the fender liners first - I'm ready to buy a GTS set....!!
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Last edited by Alan; 01-23-2012 at 12:41 PM.