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Removing the drip rails...


Guest Anonymous

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Guest Anonymous

I was going through a link Terry gave me from an earlier post, and I saw that he had removed the drip rails from the side windows. Now I had thought of the very same thing right after I bought my Z. Not only would it make the car look cleaner, it would noticeably reduce the coefficient of drag of the car (not to mention frontal area, but that's negligable. If you think this is hogwash, I've read a couple of books on automotive aerodynamics, and they deal with the very same issue, so I would venture to say that this would be good for between 0.02-0.04 improvement in the Cd of the car. How about that, a 10% reduction in drag? but I digress... Since I knew nothing about bodywork and such, I didn't think about it anymore, until I saw Terry's pics.

 

Now I'm hoping he won't mind, but here's the link:

 

http://albums.photopoint.com/j/AlbumIndex?u=1541023&a=13306335&f=0

 

Some of the pics are missing, but hopefully they will be posted soon.

 

So has anybody else done this before? I'd really appreciate it if somebody would fill us in on the hows, ifs, and whats of the modification. I'd really appreciate that.

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I am planning the same thing for my Z car (future plan WHEN I get the right car). I have not actually done it, but Terry's description makes it look relatively "easy." There is a picture on Eric Neyelin's site that has the "Black Temptress" or something like that, where the whole car has been smoothed. If he still has pictures up, it's worth looking at. Look carefully for all the details, though, because it was so well done, you may miss them.

 

Davy

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...And yes, this is VERY valid for aerodynamics... Removing Side mirrors and badges and emblems from the body helps as well. As was mentioned, the roof is a two piece sandwhich that you would have to weld when done with the cutting of the rails. That is on my schedule of mods to make!

 

Mike

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Guest Anonymous

Yeah, I searched around for previous posts on removing the drip rails, and it seems like its a pretty delicate procedure.

 

Lemme see if I got this straight, the base of the drip rail is what's used to connect the roof of the car to the body right? Seems pretty flimsy doesn't it? I know this was covered before, but I'm not sure I understood it right, why don't we just shave the rail till it is flush or nearly flush with the body? And what exactly is there to fill in/weld when we're done?

 

I'm hoping Terry or Frank will chime in soon and give us some insight on the matter and who knows, maybe do a little write up <wink wink> icon_wink.gif

 

One more thing, I've looked high and low (and everywhere in between) for pics of the "Goddess Z" or the "Black Temptress" you speak of with no avail, would one of you guys be nice enough to give me a link or something? Thanks

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First off, these rails are spot welded (about every inch to inch and a half if I remember correctly). The rail "strip" is sandwiched between the roof sheet, and the interior structure sheet. To grind the rail until close would not work because this would eliminate the spot welds completely once you got within about .120". So if you back off, and leave even half of the spot welds intact, then you are looking at quite a bit of filler to accomplish your aesthetic goal. I considered the process of simply cutting the vertical portions off only, and then bending the entire remaining portion down and in till flat and flush with the window framing, but was concerned about the distortion this would cause to the roof. I finally decided on the continuous bead wire welding method. The first side I did, I did the proceedure in sections, and there was no apparent pre-stressed seams. On the second side, I felt adventurous, and cut the entire rail off whole, at one time, and noticed NO separating or widening of the gap between the roof (was not pre-stressed at all), and structural member. At this point I tacked it every inch or so, and then came back with a continuous bead. Then ground the high spots down (and made sure I left about .030" to .050" of bead still exposed (did not grind the bead flush!!!!) to ensure a good weld. Then the bondo went on. This was the hardest part and will require many applications and sandings. Even with my long history of bodywork, the compound curve of this edge is tough to get "right". BUT, when it is right, it's beautiful. Why some of my photos are temporarily unavailable is a mystery to me. I guess I'll send off an Email about this to Photopoint. This is the first problem I've ever had with them.

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Guest Big Phil

I shaved off my rain gutters on my 78 280Z and it wasn't too difficult. The tools I used were a mig welder, grinder and a cut off wheel.

I cut off about a foot of the gutter at a time then I ground it down to until there was about 1/20 of a inch left then I welded the section together. If you do small section at a time you can keep the two pieces from separating. The welds penetrate deeper than 1/20 of a inch so you can grind the weld flush with the body so very very little bondo is needed. I also shaved off the side vents, side makers and keyholes. I changed my tailights to 89 300zx units and replaced the fuel door with a motorcycle gas cap.

http://communities.msn.com/Datsun280zClub/modsonbigphils280z.msnw

 

Phil

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Guest Big Phil

I tried a few other rear light combinations before I settled on 89 300zx models. Most taillights on newer cars wrap aroud the back so it would be difficult to mold them in. The 300zx taillights are nearly flat so they fit perfect. I got them at a local self service junk yard for 30 bucks. The middle section had to be cut down to fit an older Z because the 300zx is much wider.

 

I use the remote hatch release from a 280zx so I could shave hatch button. Eventually the doors and hatch will lock and unlock via remote control.

 

The motorcycle fuel door is off of a 90 Honda CBR. I bought the entire gas tank at a motorcycle salvage yard for 80 bucks and then I cut off the fuel door mount and welded it in. Then you just rebolt the door to the mount. This is much easier than trying to fabricate a mount from scratch.

 

Originally I had completely shaved off the stock fuel door and relocated the fuel cap behind the license plate. I add some more pictures so you guys can check it out.

 

I am new to this internet thing so if the page doesn't link to my message I apologize

 

Phil

 

web page

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Guest Anonymous

Holy Shiznit Batman! That looks Zweeeet! Love the shaved look, very clean. Was it simple hooking up the filler hose to the M/C filler? What was involved there? Also how do you fill in the holes left in by the sidemarkers, rear bumper mountings, etc? I've never done an ounce of bodywork in my life, however I'd be very open to learning. Are there any books available at Borders or B&N that you'd recommend I start with? I would really like to be able to do all this stuff myself as I would imagine a bodyshop would rape you sideways ugg.gif

 

P.S. How does $80 sound for a brand new Bullit Mustang fuel door? Would that fit right in?

http://www.telusplanet.net/public/btaylor2/Auctions/Graphics/bullitt_fueldoor.jpg

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Guest Big Phil

I thought about using one of those fuel doors from a Mustang Bullet or a Mitsubishi Eclipse but they alot cost more and they require just as much labor. My fuel door has a satin finish but you could easily polish it if you want a shiny finish. The mounting piece that I cut off the old motorcycle tank plugs directly into my fuel hose. The fuel cap mount also has a vent connection so the fuel tank's vent line can also be connected.

 

I filled in all the side makers, vents, keyholes, bumper mounting holes and antenna hole using a Mig welder. I was going to pay someone to do it but it cost so much it was cheaper to buy a welder, a couple of books and some scrap metal and teach myself. Mig welding is very easy and you have to be careful not to warp the sheetmetal but anyone could learn in a couple of days.

 

Phil

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  • 2 weeks later...
Guest Anonymous

Just wanted to let everybody know that Terry's pics of the step-by-step drip rail removal are up. Mad mad props to you Terry, that really does look terrific...

 

Could you just tell us a little bit more about the final sanding process, and getting everything to look right? Perhaps you can give us a couple pointers to make things easier for a novice... Thanks a million!

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I wish I could give pointers on the bondo part. It took me several wipes to get it right. I guess my biggest problem was the bumps in the weld bead. I did not get them perfectly smooth when I did the grinding. Thus I would sand through the bondo into the weld bead bump(s), which in turn caused this to be a high spot, so I would have to wipe again. Use a long idiot stick (not a short hand sander) to keep the broad curve smooth and even, take you time and be very patient. Site along the edge from the front and the back to make sure you are creating a smooth curve in both dimesions (up and down, left and right). Bondo work is more of a learned process that I feel can't be taught in text. The more you do, the better you will do it.

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Guest Anonymous

Hi, All

 

Pretty interesting thread here. I like what Big Phil has been doing to his project, especially his tail light treatment. When I have more time, I am gonna come back and review it all more closely and hopefully join in with a few comments.

 

Some have asked about links to the "Black Goddess Z" on my website that features such beautiful custom seam weld ups, fenching and drip rail removal by master body man Luciano Sara.

 

Haven't got that full photo display published yet, but you can see a preview at Jim Darnell's project page

 

As Phil mentioned, Luciano told me that the key to clean drip rail removal is in not removing all the sheet metal tension between the roof and sides all at once. If you cut through the factory stamped and crimpted/spot welded panels all at once, you will be in big trouble. All the roof lines will become distorted and not repairable visually afterwards, no matter how good you are with a mig/tig welder. Luciano told me that he removed small sections one at a time and carefully welded up those small slices first before moving onto more short slices until he had completed the entire removal. He told me that using this method it is possible to end up using virtually no bondo to finish the job before painting if one works with great care.

 

I just happened to dropping by today to mention a preview link to some new photos of the Silver Shadow Roadster I am planning to publish in January 'cause I have been seeing so many hits to the old Silver Shadow display at Silver Shadow I

 

True to my visual idiosyncracies, you have to scroll my SideBar Photo Pages to the right to see all the photos. At the far right of the page you will find the the link to a new photo of the car never seen before on the internet.

 

Enjoy,

 

Eric Neyerlin - owner of ZPARTS.COM

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There may be a construction difference between different models of Z cars. I did the 4" at a time method on one side, and the "cut entire rail off at once" on the other side. There was absolutely no separation or distortion what-so-ever when I cut the entire rail off with no spotwelds during the removal. BUT, again, there may be different circumstances with differing models. I very well could have used a very mininum of bondo by grinding the weld flush, but I felt that this seam needed a somewhat "full" bead for strength, and with that in mind, I left about .060" of bead exposed above the flush sheetmetal after smoothing the bead out with a grinder. This was also done to cover any inadaquacies in my welding skills being I did not want this seam to separate 10 years down the road due to flexing and vibration.

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