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hurddawg
03-18-2018, 04:37 PM
While I wait to get my stuff to together to starting working on the frame of my car, my mind has been drifting to other parts of the car...most complex being the floor pan and the firewall.

Here is what i have and my skill level:
I do have a 220v MIG welder(Lincoln) and TIG welder (Miller MaxStar150 and small argon bottle), but only have real basic knowledge of welding.

Firewall wise, I'm really interested in one of these...
http://realdealsteel.com/i-20900998-1957-chevy-4-recessed-smoothie-steel-firewall.html
http://realdealsteel.com/i-20145067-1957-smoothie-firewall.html

I guess my question here is doing a replacement of the whole firewall vs trying to fill in the holes is a better way to go for a beginner fabricator. This started to come up in my mind when thinking about how to mount the steering column & replace the master cylinder. It seems many need to fill in the steering column hole in the firewall from the tear drop shape to a circle for the mounting. My car also had a treadlevac so I have a Star Trek symbol like outline of bolts on the firewall from the backing plate (not to mention the firewall was rattle bombed black years ago and peeling). The intention is to later install raingear and have hidden A/C / heater lines so there are more parts to fill in or have holes.

I really like the recessed smoothie firewall, but wonder how easy it would be to screw up as well...I really want to do this myself as well but wonder if this is a job is too advanced to try to tackle. Being the fact that this would be so visible is another concern...

The other firewall they make sounds "easier" as they mentions installs at factory spot welds.

The floor pan, from what I remember is primarily the bad area under the rear seat.
This is the part I'm looking at...
http://realdealsteel.com/i-20145093-1956-57-chevy-4-door-hardtop-full-floor-with-braces.html

I guess I'm thinking how to go about this. Mounted to the frame? then cut out the old floor, brace the door jambs then weld the new floor in? Writing it out like that makes it sound easy....Being a beginner I really have no clue on the details of putting something like this in. Can someone fill me in?

Exhaust -
I will be working with 304 stainless. I was planning to fusion weld it only where I needed to. Ie flanges for the header, hangers and some of the bends needed to go up and over the differential. Would fusion welding be sufficient? The piping I have is 16 gauge. Should I use filler rod?

What's everyone's thoughts/suggestions?

chevynut
03-18-2018, 05:03 PM
Here is what i have and my skill level:
I do have a 220v MIG welder(Lincoln) and TIG welder (Miller MaxStar150 and small argon bottle), but only have real basic knowledge of welding.

I think you'll do best by sticking to the MIG for sheetmetal work. I recommend that if you haven't yet done so, start practicing butt welding and plug welding with the MIG until you're comfortable with it.


I guess my question here is doing a replacement of the whole firewall vs trying to fill in the holes is a better way to go for a beginner fabricator.

Personally, if you're wanting to keep a stock-looking firewall and yours is in good shape, I would just plug the holes you don't want. It'll save you $650 and the new stock firewall is probably harder to install than it looks. You can use small round plugs for anything over about 1/4" and it makes it easier to plug them. If you prefer the looks of a smooth aftermarket firewall, just go that route. It's not that hard to install one if you can master the welder.



The floor pan, from what I remember is primarily the bad area under the rear seat.
This is the part I'm looking at...
http://realdealsteel.com/i-20145093-1956-57-chevy-4-door-hardtop-full-floor-with-braces.html

(http://realdealsteel.com/i-20145093-1956-57-chevy-4-door-hardtop-full-floor-with-braces.html)
I didn't know they made a floor for a 4DHT...that's a good thing. You're smart going with a whole floor imo.


I guess I'm thinking how to go about this. Mounted to the frame? then cut out the old floor, brace the door jambs then weld the new floor in? Writing it out like that makes it sound easy....Being a beginner I really have no clue on the details of putting something like this in. Can someone fill me in?

I would use the frame as a jig and bolt the floor to it. I would brace the body, and leave the outer rockers on if you can. Remove the inner rockers and clean everything up as good as you can for welding. Repair anything else that needs to be repaired. Drill plug weld holes where you need to, being careful to make sure you can weld from that side. Deburr the weld holes. Set the body on the floor and check for fit everywhere. Once you have it where you want it put some screws, clamps, and vise grips in strategic locations to hold everything in place. When you're satisfied with the fit, start plug welding and keep going til done. :)

That's probably over-simplified but it gives you an idea. You're lucky that you have these assembled floors to use.


I will be working with 304 stainless. I was planning to fusion weld it only where I needed to. Ie flanges for the header, hangers and some of the bends needed to go up and over the differential. Would fusion welding be sufficient? The piping I have is 16 gauge. Should I use filler rod?

Unless you can do all your fitting to PERFECTION, you won't be able to fusion weld it all. I would use some small 1/16" or smaller 308 filler rod with a 1/16" TIG electrode. Some guys use .040" rod and electrodes. Keep the heat low.....like 40A or less. Be sure to practice a lot before trying to weld your exhaust.

Rick_L
03-18-2018, 05:12 PM
Lots of questions to answer from your post.

Let's start simple. Do you have rust damage to the entire floor? You say it's "primarily" just under the rear seat. How is the rest? I wouldn't replace the whole floor to only repair under the rear seat. Or is the rear floor just the worst of it?

Same question with the firewall. Is what you have in good shape, just needing holes filled and some modifications? You may just want to fill holes and modify what you have.

Your mig welder will work well for the floor and firewall no matter what you choose to do.

Tig or mig will work on the exhaust, tig would be preferred there for the stainless. You'll need need filler rod for tig (mig by definition uses filler).

Sounds like your welding skill level is low. You need to practice by doing. I'd avoid welding any panels that cost hundreds of $ until you get some practice. So start with the simplest stuff and work up from there.

Edit: looks like Cnut tree'd me. He didn't say anything that I'd disagree with, except that I'd underscore that if the floor isn't damaged everywhere, you can just repair what's wrong.

55chevysedanX4
03-18-2018, 05:32 PM
I would sandblast the floors first to see the extent of the true damage. If it is anything like mine it might look good until blasted then you could have a Swiss cheese floor which would require more than a patch here and there. If you do the full floor brace the heck out of the body before removing the floor. Ask me how I know. Then raise the body up after bracing and cutting out floor and mount the new floor to the frame and move it back under the body and reassemble. I would probably do the floor before anything else. Good luck.

chevynut
03-18-2018, 06:27 PM
I would sandblast the floors first to see the extent of the true damage.

Even then you may not see it. The rear long brace is often the first thing to rust out. These floors had nothing to protect the sheetmetal inside the braces. You could blast the floor and the braces may look good, but be on the verge of rusting out. IMO I would replace the entire floor in all but very few cases where you know everything is solid. Plus, it's often hard to make a good-looking butt-weld when replacing a floor pan, and I would not do a lap weld. I don't know, but to me a floor is cheap insurance so you don't have to mess with it again. All my braces are coated inside with Rust Bullet. Personally I'd get a floor with e-coat on it if possible since it will be inside the braces too.

55chevysedanX4
03-19-2018, 08:24 AM
where to buy rust bullet and can e-coat that is on my new floor board be welded through or do I need to clean the area to be welded when I get to that point? I am sure the originator of the thread will want to know as well.

chevynut
03-19-2018, 08:58 AM
I don't know where you can buy Rust Bullet now but you can probably do a search. However, I'm not sure how you'd use it on an assembled floor. When I did mine assembled floors were $2700 plus shipping and were only available in two halves from one source so I put mine together myself (still cost over $2000), and I was able to put the Rust Bullet inside the braces.

Rustaddict
03-19-2018, 05:09 PM
I'd think the most challenging part of putting a new one piece floor in a 4 door hard top would be getting the rear door mounting post back in the correct position.

Rick_L
03-19-2018, 07:13 PM
Amen to that on the 4 door hardtop.

Isn't Rust Bullet just a competing product equivalent to POR15? Personally I'd stay away and go with epoxy primer.

You can't weld through POR15, Rust Bullet, e-coat, or most anything but "weld through primer". And I'm suspicious of the results of that. Just my opinion.

And just how long and under what conditions do you expect your restoration to last through? Most restorations won't ever be driven in the conditions that led to original rusting. Not even close.

chevynut
03-19-2018, 07:22 PM
Rust Bullet is a moisture curing urethane similar to POR-15. It's a super-hard and durable finish. POR-15 is supposedly not to be used on clean, bare metal but Rust Bullet can be, per their specifications. I don't typically like using rust converters but Rust Bullet works well inside doors, inside tailgates, and anywhere else you can't get all the rust off. I coated the inside of my doors and tailgate with it and let it run down into the pinch welds. Since I had it, I used it inside the braces too and just brushed it on. I think it's better inside the doors than epoxy.

hurddawg
03-19-2018, 09:16 PM
Thanks for all the replies, I really appreciate the feedback :)

Re the condition of the floor. I just know the floor is rusted through under where the rear seat cushion is located, on either side of the tunnel. If memory serves me, its about 2-3" wide or so. I would assume that whole area has an issue, but really never looked to deep into it...just knew that it would need to be addressed. SO to sum up, I just know I have a bad section of floor and not sure how much other rust I might have (floor wise).

Re firewall condition - outside of the peeling paint, it doesn't have rust. Its in good shape, just looks ugly.

Rustaddict brings up good point that I did not really think of. The rear post is just anchored to the floor.

Thanks for the welding tips Laszlo & Rick_L. I wanted to weld the seam of my 2 piece frame, so that would give me some practice welding so I can move onto practicing welding thinner metal.

After reading I'm feeling a bit encouraged to try to tackle this.

Love to hear more opinions, ideas, thoughts:)

hurddawg
03-19-2018, 09:20 PM
I would sandblast the floors first to see the extent of the true damage. If it is anything like mine it might look good until blasted then you could have a Swiss cheese floor which would require more than a patch here and there. If you do the full floor brace the heck out of the body before removing the floor. Ask me how I know. Then raise the body up after bracing and cutting out floor and mount the new floor to the frame and move it back under the body and reassemble. I would probably do the floor before anything else. Good luck.

Thanks for the tips. being a 4DHT, I'm sure its one of the most flexible bodies outside of the convertible...

55chevysedanX4
03-20-2018, 07:10 AM
I'd think the most challenging part of putting a new one piece floor in a 4 door hard top would be getting the rear door mounting post back in the correct position.
I would say that is the importance of leaving the doors on and supporting the heck out of the body with bracing to insure it is going to go back together the way that it came apart.

56Safari
03-20-2018, 10:36 AM
Firewall wise, I'm really interested in one of these...
http://realdealsteel.com/i-20900998-1957-chevy-4-recessed-smoothie-steel-firewall.html
http://realdealsteel.com/i-20145067-1957-smoothie-firewall.html


What's everyone's thoughts/suggestions?


For what its worth, I looked into Real Deal Steel sheetmetal before I purchased my Goldenstar floorpan. The guy I purchased my sheetmetal from told me that the Real Deal Steel stuff is just re-badged Goldenstar stuff (and Goldenstar is really just Muscle Car GT parts).

The RDS floorpan was ~$300 more than what I could buy the Goldenstar floorpan for locally (749 out the door). I also noticed the RDS stuff is shown in bare metal on the site, but delivered in black EDP coating (leading me to believe it was shipped from overseas). In addition he cut me a deal on outer rockers and various other parts for buying them all from him.

I can't 100% confirm this to be true, but I would look around before spending extra $$$ on the same product.

Maybe someone here has gone further down this rabbit hole than myself and can chime in here?

Rick_L
03-20-2018, 01:06 PM
I think you're correct on all of the above, though I'm not familiar with "Muscle Car GT". Regardless, it's all the same parts from the same tooling, and it's imported from Taiwan.

The Golden Star floor has been the best choice for a while. And with EMI getting out of the body panel business, they're the only game in town unless someone starts building panels from the old EMI tooling. CARS Inc. was rumored to be doing that, but I haven't seen any confirmation that they are actually building and shipping.

Florida 57
03-20-2018, 05:20 PM
Randy (RDS) has maintained that prior to paint (priming) he removes the coating.Most panels many would agree that is the best approach.Floor boards I guess would be subjective for the builder on coatings removal.

hurddawg
03-28-2018, 08:51 PM
For what its worth, I looked into Real Deal Steel sheetmetal before I purchased my Goldenstar floorpan. The guy I purchased my sheetmetal from told me that the Real Deal Steel stuff is just re-badged Goldenstar stuff (and Goldenstar is really just Muscle Car GT parts).

The RDS floorpan was ~$300 more than what I could buy the Goldenstar floorpan for locally (749 out the door). I also noticed the RDS stuff is shown in bare metal on the site, but delivered in black EDP coating (leading me to believe it was shipped from overseas). In addition he cut me a deal on outer rockers and various other parts for buying them all from him.

I can't 100% confirm this to be true, but I would look around before spending extra $$$ on the same product.

Maybe someone here has gone further down this rabbit hole than myself and can chime in here?

Thanks for the tip, I searched around and found a place called Classic 2 Current and picked up the goldenstar floor pan for about $1k shipped after a coupon. I was going to hold off, but too good to pass up. I was surprised to find that the 4 door hardtop seems to have the most expensive floorpan!

Wondering if anyone thought I was crazy to try this with my current skill level? In the meantime I've read up / watched some videos on butt welding and how to weld sheet metal. Still need to try practicing though. As Rick suggested, I plan on testing out my hand by trying to repair one of my front fenders as it has started to rust & bubble on the lower part of it before I jump in on the floor. But even before that, I need to work on the frame. So just academic for the moment.

As mentioned before, I'll have to get the body blasted. I'm pretty sure toe boards, rockers, etc are good, but never know until its checked out.

chevynut
03-28-2018, 09:03 PM
Still need to try practicing though. As Rick suggested, I plan on testing out my hand by trying to repair one of my front fenders as it has started to rust & bubble on the lower part of it before I jump in on the floor.

I wouldn't jump into the fender repair until you were good at making welds on scraps of sheetmetal, 19 or 20 gauge. Welding take practice so you should try doing a lot of it before tackling the car.


As mentioned before, I'll have to get the body blasted.

Be careful with blasting a body. IMO I wouldn't let sand touch anything but the window and door openings, and anything with a lot of structure. Sand, even fine sand, can easily warp flat panels. And it doesn't take much to do it.

If you soda blast the body, you can cause paint adhesion problems. Everything has its downside, it seems.

BamaNomad
03-28-2018, 09:44 PM
In my 'younger' years I sandblasted several complete bodies without damage using my TIP 99'er pressure blaster. I always chose DRY days (not too humid which is difficult in Alabama) and did the work during warm/hot daylight hours. Once blasted the body needs to cleaned of the sand, metal prepped, dried, and protected (epoxy primer is currently the best for bare metal). I don't think my 'old' body could stand up to the 6, 7 or 8 it would take to do a complete body today. PS. When I did this, I would strip every removable part from the body hull. Do the stripped body hull one day, and the fenders, doors, hood, etc on a separate day to make sure you can get the freshly sandblasted parts cleaned and protected before nightfall and dampness/rust occurs.

I think the KEYS to avoiding panel damage while sand blasting are:

1) Do not exceed 85-100 psi or so on a pressure blaster and adjust so that you get effective but low sand flow thru the nozzle.

2) Work the nozzle always at an angle (~ 45 deg) to the surface and not directly against the body (5-6 inches away seems to work for me and my system).

3) Keep the nozzle MOVING .. if the rust is not removed the first pass, then come back to it, but do not dwell in one spot with the blaster.

4) Understand that sandblasting at the pressure I'm speaking of quickly removes rust, but does NOT remove paint quickly! I suggest using a different method for removing any paint before the sandblasting operation. I have a large tank that I filled with a diluted sodium hydroxide which would accept full fenders and doors. that stripped the paint off quickly and cleanly!

(I think to do the above, you do NOT want to use one of those huge high pressure compressors mounted on a trailer like are used in the commercial world )

LEE T
03-29-2018, 02:47 AM
Re the condition of the floor. I just know the floor is rusted through under where the rear seat cushion is located, on either side of the tunnel.

Love to hear more opinions, ideas, thoughts:)
You're not located in the rust belt, so it could be that the floor rust started on the inside of the car. Maybe a child wet his pants in the seat, or spilled a coke, both are acidic. I would suggest a thorogh inspection before tackling this.

I agree with Laslo on not blasting any outer sheet metal.

chevynut
03-29-2018, 07:44 AM
I learned a lesson about sandblasting on my Nomad. I chemically stripped the body panels, but the window and door openings with all their tight bends, etc. were difficult to do. Plus I didn't want any chemical stripper left in any nooks and crannies. So I blasted those areas.

After blasting the edges of my hood I decided to blast the rear hood brace. I should have put a sheetmetal protector between the brace and the outer skin, but I tried to be careful not to blast the underside of the skin. I was using pretty low pressure....probably 80 PSI or less at the blaster, and 80 grit silica sand (don't lecture me on the health effects please :)). My hood was virtually perfect.

Here's a pic of the underside after blasting:

8593

8595

I also did the same with the roof brace....notice I barely hit the roof skin:


8594

After priming I started blocking the parts some time later. I was baffled as to why I had a big dip at the back of the hood. It was literally 1/16" deep and I had to bodywork it and use Slicksand to get it back to where it should be. I couldn't figure out why it was low there for quite a while.....I think it was when we were discussing a trunk lid that got ruined by sandblasting on the other site. Then it hit me. Also, when I blocked out the roof there was a slight low spot in front of the brace. I'm convinced that you should NEVER touch flat sheetmetal with a sandblaster, no matter how "careful" you are.

Here's the hood after blocking Slicksand:

8596

Bodyworking:

8597

Finished:

8598

BamaNomad
03-29-2018, 07:51 AM
It seems you were removing Paint rather than rust, Laszlo?? Rust comes off quickly with the sand blasting, but paint is VERY SLOW to be removed, and I suspect that is where the warpage is coming from... I would not use a sandblaster to remove PAINT... I only use sandblaster to remove RUST...

Gary

bigblock
03-29-2018, 08:13 AM
So is it best to remove the paint first or the rust?

chevynut
03-29-2018, 08:18 AM
It seems you were removing Paint rather than rust, Laszlo?? Rust comes off quickly with the sand blasting, but paint is VERY SLOW to be removed, and I suspect that is where the warpage is coming from... I would not use a sandblaster to remove PAINT... I only use sandblaster to remove RUST...Gary

I find paint comes off easy with a sandblaster.....easier than rust. The paint on my hood brace was very thin and I don't even remember if there was any on the roof brace. I don't think there was any rust, or very little. If you're only blasting paint, you won't warp the metal. It occurs when you actually HIT the metal. Warpage from sandblasting is caused by the sharp particles "peening" the metal on one side, thereby stretching it only on that side. That's why I had a dip in those places....when the metal stretched it moved TOWARD the blaster nozzle.

On the other site a guy has his car sandblasted. He showed pics of a "ruined" trunk lid that had dips at every opening in the underside brace. What happened is the blaster blasted the underside of the lid, and hit the outer skin, stretching the metal. You can prove this to yourself with a blast cabinet. Take a flat piece of sheetmetal and blast one side. It will "cup" toward the blaster nozzle. Flip it over and blast the other side....it will straighten out. I've actually used my blast cabinet to fix oilcanning of some smaller parts like covers, etc. by blasting them and stretching where needed. I use glass beads in the cabinet.

This is the car after stripping pretty much all the paint I removed with stripper:

8599

This is after blasting (I replaced both quarter panels):

8600

bigblock
03-29-2018, 08:30 AM
Thanks CN I hope to be able to start on my body soon, I'll try to post before and during pictures. Thanks to all you guys!!!:)

LEE T
03-29-2018, 09:04 AM
All paints are not the same, some are easy some are not, and the same is true of rust. Pitted rust is hard to remove, depending on the depth of the pits. Blasting sheet metal with a radius is safer than blasting a hood.

Blasting media is also deferent, sand is hard and sharp, crushed glass is not so hard but it is still sharp, glass beads are not hard and not sharp, but they don't work well for this application, so I don't think its a good idea to recommend that anyone can blast sheet metal without any problems. JMO