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Rust Repair (The Correct Way) by DimeMachine
Started on: 01-23-2021 09:24 AM
Replies: 10 (499 views)
Last post by: theogre on 01-31-2021 07:01 PM
DimeMachine
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Report this Post01-23-2021 09:24 AM Click Here to See the Profile for DimeMachineSend a Private Message to DimeMachineEdit/Delete MessageReply w/QuoteDirect Link to This Post
If you have a Fiero, then chances are you have (or will) be dealing with RUST. It is a 37+ year old car - so if it has been driven, moisture - perhaps even salt have gotten to the space frame metal and worked their destruction. If you do find some rust through - here is how to deal with it correctly. No paint over B.S.... Lets repair it the right way.



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[This message has been edited by DimeMachine (edited 01-23-2021).]

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RWDPLZ
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Report this Post01-23-2021 10:26 AM Click Here to See the Profile for RWDPLZClick Here to visit RWDPLZ's HomePageSend a Private Message to RWDPLZEdit/Delete MessageReply w/QuoteDirect Link to This Post
If it's that bad at the base of the strut tower, what do the upper rails look like?
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DimeMachine
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Report this Post01-23-2021 11:43 AM Click Here to See the Profile for DimeMachineSend a Private Message to DimeMachineEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by RWDPLZ:

If it's that bad at the base of the strut tower, what do the upper rails look like?


They were shot!. I rebuilt 85% of them 15 years ago when I restored the chassis.

This is a "15 year tune up" as I spotted this newer rust thru and had to deal with it.
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liv4God
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Report this Post01-24-2021 07:46 PM Click Here to See the Profile for liv4GodSend a Private Message to liv4GodEdit/Delete MessageReply w/QuoteDirect Link to This Post
Nicely done video! I hadn't seen your channel before, watched some of the other videos and gave you a follow.

I do have a question about the repair, I noticed the sheet metal you are using to fill in is very thin, thinner than the original. Won't that decrease the structural integrity?
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DimeMachine
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Report this Post01-24-2021 11:46 PM Click Here to See the Profile for DimeMachineSend a Private Message to DimeMachineEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by liv4God:

Nicely done video! I hadn't seen your channel before, watched some of the other videos and gave you a follow.

I do have a question about the repair, I noticed the sheet metal you are using to fill in is very thin, thinner than the original. Won't that decrease the structural integrity?



Good eye, you are correct & thanks for the kind words!

That having been said, the replacement metal is a little thinner than the original metal - but I am not concerned about it. The metal in this part of the strut tower is mostly under tension (achieving maximum stress when the vehicle hits hard bumps) & little if any shear and certainly no compression. I am pretty certain it will not tear - in fact, I am kind of surprised at the relatively few spot welds that hold the tower to the lower frame rail from the factory...

Truth be told, this chassis was in quite rough shape 15 years ago when I first repaired a ton of rot - mostly rot to the upper rails (they were mostly gone). The space frame along the underside of the rockers was also in rough shape (not just the clamps holding the coolant tubes) and the rear subframe also has some spots that are probably quite thin compared to the day they rolled out of the factory (as well as couple of holes that needed to be patched ((damn MN Saltl!!)). I am almost surprised the strut tower stayed where it belongs back then - it was that bad!

Anyhow, patched up from 15 years this is a toy and no longer is exposed to any winter driving and little if any rainy days. I have over tripled the H.P. and the chassis (& strut towers) show no signs of moving.

[This message has been edited by DimeMachine (edited 01-25-2021).]

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olejoedad
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Report this Post01-25-2021 11:31 AM Click Here to See the Profile for olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Nice video and repair, but....

The steel in that area of the space frame is high strength.

You should use the proper thickness and type of steel - not tin-snip cut sheet metal.
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DimeMachine
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Report this Post01-25-2021 12:49 PM Click Here to See the Profile for DimeMachineSend a Private Message to DimeMachineEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by olejoedad:

Nice video and repair, but....

The steel in that area of the space frame is high strength.

You should use the proper thickness and type of steel - not tin-snip cut sheet metal.



Agreed - what you describe would indeed be better - and rust preventer (3M Cavity Wax) within the frame rail after the repair.

I will note these things in part 2. I have added some thicker metal (still mild steel) along the right edge of the shock tower to compensate for the thinner metal used. Main thing I want to relay is stay away from the P.O.R. (paint-over the-rust products), fiberglass jobs, pop rivets and scrap tin cans etc - if you have been around cars for a while - you have seen it!

Thanks!

Dime

[This message has been edited by DimeMachine (edited 01-25-2021).]

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olejoedad
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Report this Post01-26-2021 09:01 AM Click Here to See the Profile for olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Eastwood makes some super rust reformer for use inside cavities such as frame rails, etc.

The applicator has a nifty little tip that paints in a 360° pattern, covering the entire inside of the cavity.

Sadly, (or fortunately) I've done a lot of chassis rust repair on several Fieros (and other cars) over the years.

Looking forward to the next video.
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reinhart
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Report this Post01-31-2021 04:12 AM Click Here to See the Profile for reinhartSend a Private Message to reinhartEdit/Delete MessageReply w/QuoteDirect Link to This Post
Is this an 87 with "Formula" decal? It's not an 88 suspension obviously.
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DimeMachine
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Report this Post01-31-2021 09:50 AM Click Here to See the Profile for DimeMachineSend a Private Message to DimeMachineEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by reinhart:

Is this an 87 with "Formula" decal? It's not an 88 suspension obviously.


Yes - good eye!

Here is the story. I have had Fiero's most of the past 31 years. For a brief time (5 years) I took a break and had none.

Back in 2003, my dad had a real 88 White Formula (and still does) and he also had a couple of rusty old Fiero's (84 & 87) that had seen better days. One day he called me up ( late 2003 I believe) and said "I am getting rid of the two old Fieros - if you want them they are yours - or I am selling on craigslist.

It was fall in Minnesota and I thought - this would be a fun winter project. So I stripped them both down - all the way down to just spaceframes tipped upside down in my shop to inspect the extend of rust damage. I took the best of each car which (generally speaking) ended up being the 84 chassis and most of the 87 body panels and of course the superior 87 complete wiring harness and headlight system. I repaired the extensive rust damage and put everthing back together. The old blue (87) and black (84) paint did not look great so I thought I would make a White 87 Clone. So I did.

It was a fun day to pull into my dads driveway next to his real 88 White with my fake two scrap car restored into a White Formula clone. We both got a kick out of it. 18 years later we both still have them.

Sorry for the long story - but I think most of us Fiero guys have some crazy ones!!

Cheers!
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theogre
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Report this Post01-31-2021 07:01 PM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
Patching is good but metal should be same thickness and close to same type.
You won't want SS patch in cold rolled steel frame or the tower wall.
You cut a patch w/ hand cutters then metal is likely too thin and weak.

You should have use open hole to inspect the frame inside using mirrors, small camera or bore scope.

Missing Tower wall area should have overlapped patch that spans the frame patch and cut off tower.

Stick and TIG and other wire feed welding to frame might be ok, Not so much to weld on the struck tower. GM and others uses Spot welds for more reasons than just cheap. Spot welding won't heat a whole panel to screw up metal hardness etc. Even when have a lot of them.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)


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