Good day all, I searched around a bit and didn't really find much on front fenders. Lots on extending rear fenders of course....So I'm wondering about is extending the front fenders, say like on a 48 Lincoln(in blue below) where they stop abrupty before the door VS a 48 Chevy(in red below) where they flow back into the doors....yeah, I know, Chevy having a smoother design than the LIncoln, crazy..anywho....it seems that the cars that have the feder extensions into the door have the door extended further forward into the fender instead of the dividing line between the door and fender being right at the hinge line. This is obviously so the turnign radius of the front of the door will dive in quicker and not go into the fender as much....as well as your door gets thicker(from the hinge to outer surface) you need to move you hinge back further for this same reason .....is there a relationship that is used as a rule of thumb that is used like If the door is 6 inches thick, the hinge should be 3 inches back from the front of the door...etc etc....I guess I can draw up some simple geometry and figure this relationship out, but just thought I'd see if anybody has experience with this firsthand. I know you could buy "add on" fender extentions back in the day for customizing but I have never done this particular mod myself....Any info is appreciated..here are two examples form my above references...what we are trying to accomplish is to make the Lincoln flow into the door like the chevy does.... Thanks, hans
My 46 Olds has the door caps similar to the 'A' body Chevy convertible you posted, only longer being a 'B' body.. The door caps are not flush where they meet the fenders and are slightly recessed. As you open the door they tuck under the rear edge of the fender. The front fenders need to be pumped out considerably to achieve this and extend into the door. There is also an extension under the door cap that acts as a filler panels and follows the profile of the door cap so there is no gap to the sill panel. The hinges on my Olds don't appear to be different to the earlier '41 model without door caps and similar to the Lincoln.
I believe that was called "fade away fenders" back in the day. J.C Whitney and other companies sold kits to do that.
Also consider the positions of the hinges. The door hinges on my Morris Minor were designed for a fender-into-door scenario from the start, without reference to any foregoing geometry, and consequently the hinges are close to the outer skin of the fender (or wing, in this case). This did mean that the door hinges were close together in the lower part of the door, and therefore had to be fairly stout items (mine seem to have held up all right for 53 years); but it also meant a fairly simple cut line without a lot of compensating curvature. I'd think that this approach - moving the hinges further outboard - might also have some advantages for weathersealing as the front of the door window frame will more tuck in behind the A-pillar than simply drop into a rebate. Done right the door seal might compress in a more effective way.
Yeah, bringing the pivot point out would help as well, but you also have to consider the hinges have to be in the same plane, so the upper hinge has limited movement before they become extrenal hinges...Early cvars ahd external hinges because they had to with a simple hinge and a cowl that had no recess for the door to swing into. Hans
That's the thing. You'd have to move the top hinge down into the fender, which means that the hinges would hold the door over a narrower base and therefore have greater forces acting on them.
The "secret" is not in the hinges. Notice that the leading edge of the fender extension is not a 90 degree verticle drop but is sort of scalloped. The scallop will be different from car to car according to the shape and depth of the fender. Google up "How to fit Crown Moulding" to get a idea of how figure out the shape of the front edge of the fender extension. It is much the same as "coping" a crown moulding joint. Also note that the front edge of the extension is not chopped off, but has a lip to under lap the trailing edge of the fender. The hinges have the proper geometry all ready to clear the cowl when opening and shouldn't need any changes.
This is kind of opposite of what you want , I guess. My fenders were part of the door but I wanted to open the doors the other way, so i fabbbed the door fender pcs. to the fender and cut the door to fit
If it was my car, I would make 2 mock ups using resin to make a cast of the rear portion of the front fender and figure it out. I don't think you need to change the hinge geometry, but would consider the added weight to the hinges.
As you already noticed the rear part of the fender has to taper down so it can tuck inside the front part. And the cut line needs to be contoured to allow this. Why not make mockups out of stiff cardboard and practice opening the doors? When you get the fender line you want, and the door will open without anything hitting, use the cardboard as patterns for the steel parts.
it's not fundamentally much different from what guys were doing building IMSA cars and having to adapt widened/lengthened fenders to existing bodyshells, and this done with unibody cars that would be very difficult to change the geometry of the door hinging on. even the tuner craze a few years back of adding "strakes" to everything... it's a matter of finding the curvature needed to allow the door part to clear the fender part. look at how the GM cars from the era managed it to get the idea. several lines would use the same basic bodyshell but the "look" of the car came from what Buick could add that Chevy did not, per se.... ads for these were in the car mags for years... they had to work fairly well and be easy to install if they sold well enough to warrant continued advertising!
I do have a ton of photos and 5,200 + hours in it so far but have not really took the time to organize any of the pics., someday maybe.
That's where this goes, but I decided to 2 tone the car so the engine gets stripped again and the block gets a bright yellow on it.
Hans, Gerry Burger did a tech article in the August 1997 issue of Rodders Digest on extending the front fenders on a 1948 Chevy. The name of the article is "Fade Away Quarters". It may not be exactly what you are looking for but it may spark a couple of ideas.
It's fairly easy as on the gm cars mentioned. The headache comes when the fender is peaked, and goes down from the peak to the body, if thats the case, make a template of the fender shape, then turn it 90 degrees and draw your cut line. (I learned this on my Zephyr) I'm to dumb to put pictures on , but on my lincoln the stock fender was like yours. I added a rear fender to it, made the template, turned it 90* cut with a die grinder the boxed,braced and cleaned it up. Roger
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