front fender rust - near sill.

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garyinwestoz
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front fender rust - near sill.

Post by garyinwestoz »

One of the issues with this car - and all my others actually - is rust about the front fenders, at the sill level - this is where road muck gets caught against the inner wheel well liner, creating a nice spot for this muck to accumulate, and with constant wetting eventually it causes rust from the inside out to the fender.

If you are smart enough to catch it + clean out the inner liner, then you can prevent the sill corner from rusting too.

Well I took the fender off today ( Right side)

and lucky me the sill corner has signs of rust

Image

so I wire brushed, grinded and sanded the surface to see how bad it was. - its got holes

Image

Image

I also attacked the fender with the abrasives to see how bad it is.
Image

I suppose its not too bad, maybe a bit of metal patching is all it needs
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nope - back side is very rusty and part of the support fame has completely gone
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My options I suppose are;
1. to fill the area with fibreglass, then sand and paint over
2. cut out the rusty areas and replace with new metal

Im favouring cutting out rust and replacing with new metal

I have another fender thats got a reasonable support pieces, so I'l take a template off to make a duplicate.

So I started.

card clamped to metal, marked then cut out, then repeated.
Image

2 pieces laid out
Image

Im wondering if a flexible shape pattern maybe the way to go?

Metal Fabrication: How to make a Flexible Shape Pattern and Gauges by Wray Schelin's ProShaper Workshop

"https://www.youtube.com/embed/y-JQgPm4_7s"
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
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79 528i auto parts car
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garyinwestoz
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Re: front fender rust - near sill.

Post by garyinwestoz »

This morning , I thought I would remove the LF fender and see how that fared. - ( before going to church)

Image

a bit of a hole in the underside of the panel

Image[/url]

a bit of rust on the sill, but mainly surface - looks like I may be attending to this just in time,. Figuring clean up with wire disk, sanding , rust treat then repaint.

Image

The panel though needs a metal patch. Thankfully the support piece is not damaged at all.

Image
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
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keehn
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Re: front fender rust - near sill.

Post by keehn »

Gary,

You might have another option: if you didn't want to cut out the rusty sections (after cleaning, of course), you could use lead as a body filler instead of fiberglass or bondo.

The distinction with lead is that it's not just a filler, but it contributes to the structure of the piece, effectively becoming fresh metal that can be sanded, formed and treated like a normal piece of metal.

There's a rusty section on Eleanor's right-side fender hood sill that I plan to use lead for. It will be a learning experience for me, but I do know how to solder, and this is kind of like the same, only on a bigger scale.

Or, you could always cut out the piece and weld on a fresh piece from a donor, or custom formed.

Mike
garyinwestoz
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Re: front fender rust - near sill.

Post by garyinwestoz »

For the sill, I made a flexible shape pattern

Image

I taped over this area with 2 layers of masking tape - 1st @ 45 degrees then 2nd 90 degrees to each other . Quite a few folds were created in the tape, but that might not matter. I dont have any fibreglass tape, so hopefully the 2 layers will be okay.

Image

I have a piece a of metal from a rear quarter panel that I have kept which I can use - here is the shape pattern over the piece showing how much shape needs to be created.

Image

I cleaned it up and trimmed it to size

ImageImageImage

after a bit of hammering on a my hollow block I started to get some shape
Image

I also trimmed the piece a bit more to fit the shape pattern, bit more banging, on both log and my steel anvil ( cut off 150 UB) and was starting to get pretty close.
Here it is test fitted - Im finding it difficult to get a really tight fit and get the bend sharper.

Image

Image

view form underside - here can see quite a gap still - wher there is too much shape
Image

My shape pattern is loosing a bits of its firmness - I think the fibreglass tape layer would have helped quite a bit for it to keep its integrity. I also think I ought to have started with the major bend first- it may have resulted in a tighter bend.
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
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Joined: Thu Jan 29, 2009 9:05 pm
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Re: front fender rust - near sill.

Post by garyinwestoz »

keehn wrote: Mon Oct 19, 2020 8:54 am Gary,

You might have another option: if you didn't want to cut out the rusty sections (after cleaning, of course), you could use lead as a body filler instead of fiberglass or bondo.

The distinction with lead is that it's not just a filler, but it contributes to the structure of the piece, effectively becoming fresh metal that can be sanded, formed and treated like a normal piece of metal.

<snip>

Mike
good idea - I was considering running off and getting some fake filler!! but lead would be way better. We have a sheet of lead (roof flashing) at my inlaws I can have..hmmm or do I need to used proper automotive stuff.

Is brazing an option too?

I've recently received David Gardiners metalshaping DVD - he has a bit on led filling on it. Its a very good DVD.

https://www.classicmetalshaping.co.uk/dvd/
watching that has given me the confidence to " have a go ya mug" - thats an Aussie saying.
Last edited by garyinwestoz on Tue Oct 20, 2020 11:46 pm, edited 1 time in total.
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
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keehn
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Location: Clear Spring, MD

Re: front fender rust - near sill.

Post by keehn »

Gary,

That's a "bang up" job you're doing :lol: Seriously though, it looks great! I'd imagine you could get a perfectly smooth contour if you had an english wheel, since a beanbag and hammers can only go so far.

Also, concerning fillers, I'd imagine it would depend on the purity of the lead. I have researched the various types (e.g. tin/lead) and lead is the metal to use if you are concerned about heat (it has the lowest melting point of filler metals). Of course, be sure to wear gloves, don't touch, don't eat, blah, blah, blah. I'm not sure on brazing - this filler method is very much like brazing, and I wouldn't be surprised if the terms are used interchangeably when describing this process.

Here's a good video from Eastwood on using lead body filler I'd highly suggest anybody who's interested in trying this to watch:

https://www.youtube.com/watch?v=87fuTnB ... e=emb_logo

And the URL to the Eastwood site selling the lead tools and materials:

https://www.eastwood.com/autobody/leadi ... older.html

Like soldering, this looks like it could be perfected with practice. I have a rusty Ford F350 dually that I can experiment on before I go for the real thing, I would advise anyone else to practice as well.

But again, lead filler has the benefit of being structurally sound, and effectively becomes part of the sheet metal, unlike Bondo or non-metal fillers.

Mike
garyinwestoz
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Re: front fender rust - near sill.

Post by garyinwestoz »

Im not to sure if my bend it sharp enough, so I made a card template to check.

Image


as can see, still needs at bit of shape = probably stretching to match and its not very even. I'm surprised actually that I got it this close!

Image
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
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Re: front fender rust - near sill.

Post by garyinwestoz »

I remembered that I cut out his section form a car that was going to scrap. So I went and got it this evening

Image

Might make a nice form to bash against as its really quite stiff.

I need to use this piece for the 79 SA car, which has a rusty door frame and sill corner, which this piece is to replace.

It looks like this piece maybe even available new !

Image
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
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Re: front fender rust - near sill.

Post by garyinwestoz »

I sent and email to Wallothnesh and they replied saying
"sorry but the part you ask for is not available and we don´t have a new delivery date yet.

Best regards
Alexander Nesch
bugger - looks like I have to keep pounding away.
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: front fender rust - near sill.

Post by garyinwestoz »

I decided to move onto a fender and come back to the sill later

The right side fender looks like some had previously repaired it as it has a plate on the backside tak welded on and lots of filler, which I scraped off to reveal the extent of the damage, therefore its going to need a full replacement piece.

Image


Image

I've made one up but cant find it, so time to make another - good practise I suppose

Firstly I made a card template to get the basic shape and size of steel sheet I need. I have a 5 fenders here and this pattern is close to all of them - but there is a variation on each of them - just a few mm's.


Image


I transposed this template over some steel, putting in the required marks and denotations, then cut the steel out fairly close to the shape - allowing a bit extra to be trimmed off later.


then I made the first bend -by clamping the sheet to my mobile benchtop with a piece of angle and 2 clamps, then bend with hands to approx angle.
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Checked a couple of time until it was fairly close - I can adjust it later to get it spot on. I also did the bottom fold this way too.
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then checked this all against the fender pattern - taking shape nicely

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Then I had to attend to the funny shape at the bottom - its a bit like a flange , so referring to the metal shaping video, I made a combination of flat surface ( UB cutoff) , metal plate and clamps and hammered away with a flat bolster to get the metal to move.

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Not having not done it this way before, I was amazed that it actually worked.

Then I made the last bend over the edge of the UB. Because the underlying shape was not flat, but the fold line is straight, instead of bending with my fingers, I was going to have to hammer form it by small increments to make the metal move. So , clamping down the face thats not to move, then hammering the free edge along the fold line, starting at the ends and moving towards the middle, a little bit a tthe time, I got the metal to move where I wanted it to go, without causing any buckles or mishape.

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I noticed that the bottom edge had an unusual cut line, which is on all the fenders, so I traced the line onto the metal and cut with tin snips.
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There was have it. All that needs now is to fold over the edges, cut off the damaged fender part, trim the new part to size, gas weld the new part to the fender and finish of the edge, folding over the rib.- sounds easy !!!

Image
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
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Re: front fender rust - near sill.

Post by garyinwestoz »

The steel that I made this section with seems to be quite different to fender material - my test gas welding produced undesireable results ( melted at a high temp than the fender material - causing holes rather than fusion joins ) , so I went to a local coachbuilder and got some off cuts of the stuff they use and then following the sam process, made another then made the other side. So now I have a left and a right - both off the same pattern.

Image

All I have to do now is add the trim body line, do a final planishing then weld the new section in.

I also have to make a support rib for the Right side fender - which is rather rotted.

rotted out support rib

Image
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
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Re: front fender rust - near sill.

Post by garyinwestoz »

I got referred to this youtube video to create the bend in the rib.

https://www.youtube.com/watch?v=V-R_kVKKBEI
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: front fender rust - near sill.

Post by garyinwestoz »

Following this technique, I made up a follower piece form 5mm plate, then clamped the piece to a vice, and bent over the straight section approx 25 degrees, then hammered over the curved section sorta the same with my wood mallet.

I was quite please with this initial bending.
Image

Image


Maybe it was my vise, but the more I then tried to bend the materials, the more the bend started to move off line. I think the follower moved.
Also I noticed that the apex of the fold tended to flatten out which further moved the follower.

Image

Wacking of the the 'tuck' did nothing, but cause my good straight bend to become distorted and create movement else where ( along bend line)

Image


It was suggested to me to clamp the piece between 2 bits of shaped steel, so I shaped the end of a bit of structural angle I have. I then
remarked the line, unfolded the piece a bit then clamped the piece between the pieces of steel, and refolded with a hammer, which has worked much better at maintaining the correct folding line location.

Image

but

Its created an enormous pucker which I guess needs shrinking.

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well, in the absense of knowing what else to do, I just kept hammering away using various sorts of "dollies" to get some shrinking of the pucker ( shrinking, in the absence a fixed edge seems to be more like relocation or displacement).

my 2 hammers and various bits of steel used for dollies - the left end curved dolly was used most as it was fairly close to the required curve - and I could hold it in position, just above the clamp screws shafts

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I clamped the flat fold to stop that from deforming - which seemed to work well.

Image

The far left edge wanted to fold over the steel forms, so I measured how much I needed and cut off that excess ( about 10mm) , hoping that would stop the metal from moving over in that direction.


about 20 mintues later, the pucker reduced to almost nothing!!! Wow

Image

Image


It appears that the hammering of the pucker has displaced the metal to the outer edge, such that it now bulges instead of being straight - I guess I just trim the excess off.

Then a bit of little bit of fine tuning and add in the perpendicular ridge/panelline.

Perpedicular ridge now added, extra fold added to lip as per original

Image

then trim edge to size and

then test fitted to show how it matches - yippee pretty good - for a novice!

Image

To get teh reinforcing rib, as per the original and as per the suggestions on Metalmeet forum, I cut a small notch in a piece of angle,

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clamped the piece then using the end of the hammer, knocked the notch in - thank fully the piece did not deform
Image


and was able to test fit in place.

notch is not as big as the original - but ought to be okay I suppose.

Image

You can see in this last photo that I have welded in the fender patch panel.

before cutting any of the fender, I made some profiles - inside and outside lines. I think I heard peter tommassini say somewhere - "always make profiles"

Image

Using that as a guide, I trimmed the rib then welded that in place -

I have a Henrob/cobra 2000 torch , I used the tip no 1 ( 1-3.0mm) yesterday and think it was too big. so I swapped to no 0.5 ( ) which book says is for upto 1.5mm

Any way weld is much better and heat area is much smaller - A bit of planishing after the tacks kept the join reasonably flush.

I still blew a few holes, which I filled with bit of cut off.

Image

I think the original panel is thinner than my patch panel, as it tended with liquifiy much quicker.

Where the rib touched the fender, I put a stainless steel knife underneath, hoping that the weld would not go through - which seemed to have worked.
I also sprayed a bit of zinc primer under neath as wont be able to get to it later.

Image

anyway, I hope this will okay.

Putting up the inner guide suggested that I've got this reasonably spot on.

Image

Image
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
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Re: front fender rust - near sill.

Post by garyinwestoz »

following on form the earlier post
garyinwestoz wrote: Sat Oct 24, 2020 3:23 am <snip> So now I have a left and a right - both off the same pattern.

Image

All I have to do now is add the trim body line, do a final planishing then weld the new section in.

I also have to make a support rib for the Right side fender - which is rather rotted.

rotted out support rib

Image

so prior to installed the rib, I cut and removed the rust from the fender,
trimmed the piece I had made which now included the body line swage

then gas welded into place - this is my first attempt (ever) at gas welding, so it was very rough


Image


panel deformed a bit, but was able to knock it back into shape with hammer and dolly.

back side weld - not sure if fully penetrated can see join line after sanding extra filler off.

Image

my biggest problem was I kept blowing holes in the joint!

and maybe l I could have have made the joint a full straight line cross - but I was worried if I did that then the whole panel is relying on the quality of my welding ( which is poor) where as the stepped join allowed for a bit of structural overlapping - which ought help keep the fender in correct shape - despite my welding.
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
garyinwestoz
Posts: 321
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: front fender rust - near sill.

Post by garyinwestoz »

folded over fender lip
Image

kinda looks okay I suppose
Image

test fitted - not too bad
Image

sprayed some primer after cleaning up weld high spots - probably could do with a bit of filler -I had some fibreglass resin which I used along with bit of cloth to make smooth.

Image

this is the other side
Image

painted and installed - RHS
Image

LHS
Image

curve is slightly off

Image

As it sits this week - ready for re-inspection
Image
77 528i -4 speed manual getting rusty
76 525 - 4 speed, LPG and holley carb- restoring
81 528i - auto - to be relicensed with a 3.5 (83 735i)
80 528i auto - ready to relicense
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual- dd
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