floor pan now or later?

[ben1272]

My floor pan is drilled and cleco'd. I have not painted it (inside or out) and was wondering what you guys think:

- Is it worth it to paint it or does it get wrecked (on the underside) anyways and stays better looking without paint? (I'll probably paint inside black to match steel floors)

- Should I rivet on or leave off til later for easier access? I was thinking that by putting it on permanently now, it forces me to approach the build in the same way I will have to service the car, i.e. with the floor in place. Future serviceability might be improved if I build it with floor 'in the way' and work around its presence?

I've seen some approaches on build threads, but was thinking some of you might have changed mind on order of operations, finish, etc., after getting further into build.

Thanks in advance for any replies!

-Ben

[billjr212]

Make sure you are 100% happy with your seat mounts and seat belts. At that point, I would say you can go ahead and rivet in place.

I used rubberized undercoating on the bottom and top of that pan. Holding up fine over 2,000 miles.

[ben1272]

Thanks for those suggestions. Did you undercoat the aluminum directly or did you prime it first?

[Wayne Presley]

The floor pan is the last thing I put on the cars, everything can be put on before and no reason to put it on until its done.

[billjr212]

I scuffed with steel wool, cleaned, and undercoated. Primer would give you more resistance to abrasion, as the stuff will come off easily if you catch it with a tool in a sweeping motion. Good thing about the rubberized undercoating is that it is easy to touch up if you feel the need (I haven't yet).

Wayne is right though. You technically can wait on that panel until just before you put the body on and even then you can do both essentially in tandem.

[AZPete]

I agree it is best to rivet the floor pan after everything above it is done, but I like the new way Factory Five says you can tip the chassis up at the start of the build. So, do the best of both methods: tip the chassis on its side, clamp the floor pan in place and drill all the rivet holes and then use a few #8 screws to hold it in place. Then, after you have mounted the seats, wiring, and everything else, rivet the floor pan in place. For a coating, its hard to beat powder coating.

[redfogo]

Yes save this for last. When I got my kit I was so excited and followed the manual step by step, then noticed my mistake of putting on the floor pan before I had welded in my seat brackets. Lots of rivets to remove after that! Hold off tell your done and ready to go not worth jumping on early. That's when I noticed I shouldn't follow the manual step by step..

[longislandwrx]

I haven't done mine yet either, I was worried I would drop a heavy tool like a hammer on it and dent it. I will wait until the end, jack up one side of the car and silicone and rivet.

[Hindsight]

It seems everyone is talking about riveting the panel in place. Did anyone use rivnuts with bolts instead? That is what I've been planning on doing because I know I will need to remove the floor pan to remove the seats and harnesses from time to time and I don't want to have to drill out rivets to do it.

[billjr212]

It seems everyone is talking about riveting the panel in place. Did anyone use rivnuts with bolts instead? That is what I've been planning on doing because I know I will need to remove the floor pan to remove the seats and harnesses from time to time and I don't want to have to drill out rivets to do it.

You would also have to re engineer the panel a bit because it ends up sandwiched between the body and frame on each side.

[Bob_n_Cincy]

I had 100 autocross runs on my car before I put on the floor pan. I love having easy access to everything.
It has been on for the last year with 1/8" pop rivets & silicon. (no coating). I do not foresee a need to ever take it off.
I did drill about (20) 1/4" holes in it to drain water.
Bob

[RetroRacing]

the way they do it on most tube frame cars is to not pre drill any holes, use a 70 series aluminum, use a high temp silicone, turn the car upside down, heat the aluminum up with a torch, drill and rivet while keeping the aluminum hot. When it cools, and shrinks, it's tight like a drum and adds some structural elements to the frame.
Of course, we did not do that, we got excited and glued and riveted cold.

[Wayne Presley]

You can put the panel in a competed car, slide the panel deep on one side then slide it back under the opposite body side. I drill and tap the frame and use 10/32 screws.

[Hindsight]

Thanks for the input all.

Wayne, that's a great idea. When you do it this way, do you add any kind of gasket to help with water proofing? I was thinking about adding some sort of thin foam adhesive weather strip tape to the frame or pan, then adding the bolts as you mentioned. I was going to do rivnuts but I like your 10/32 screw idea better.

[Wayne Presley]

I carpet the panel and then screw it in, no rattles.

[Hindsight]

Cool, thanks Wayne.

[DSR-3]

I went with the "now" option, after figuring out & making seat/belts mounting, and before installing anything too heavy on the chassis. With the chassis on the dolly-stands, I positioned both panels and marked tube locations from above. Then removed, drilled and sanded the panels. Tipped the chassis, did the drilling, cleco'ing, gooping, and riveting all by myself. Finished (underside only) with herculiner. Tipping the car on it's side (or top) is the way to go (I think). I would not enjoy all that upside-down work on my back under the chassis!54501

[ben1272]

Did you paint entire underside with herculiner? Have a picture by any chance?

[ben1272]

I carpet the panel and then screw it in, no rattles.

Wait, so you carpet the entire panel and then screw it to the frame, sandwiching the carpet between the aluminum sheet and the tube frame?

[DSR-3]

Did you paint entire underside with herculiner? Have a picture by any chance?
I was worried about not having enough herculiner, and did only the aluminum panels, which came out good, but the whole underside would "look" better- if you're looking. No pictures I can find. It's a heavy coating filled with chunks of rubber(?), and part of the trick is keeping the chunks evenly applied. It's a messy process, and definitely one not to do on your back under the car if possible.

[ssssly]

I also did mine first. I have not coated it yet since I haven't put in the seats and harness etc (Magnet paint Chassis Saver, more impact resistant than por 15, UV stable and bendable so it won't crack if the aluminum flexes).

Figured that way if it needs access points, I can cut or drill exactly where the access points will need to be and then install plugs or access panels for future maintenance.

With my back, laying on the ground to do all those rivets isn't really an option.

[redfogo]

I installed mine alone from under that car. I really didn't find it very hard. I used wood blocks and some jacks to hold the panel in place while I installed. I am sure if you had the whole frame flipped it woudl be more easy. But I would have no problem doing it from under the car. I plan to do the same thing again when I reinstall.

[Bob_n_Cincy]

First go kart mode, then cockpit aluminum and body install last. we put the car up on blocks for easy aluminum and body install. It worked out great for us.
Bob

54513 54510 54512 54511

[TX-Lou]

It seems everyone is talking about riveting the panel in place. Did anyone use rivnuts with bolts instead? That is what I've been planning on doing because I know I will need to remove the floor pan to remove the seats and harnesses from time to time and I don't want to have to drill out rivets to do it.

We put the frame on its side first thing and went the rivnut route in our build. When we are done with the seats and harness we plan silicone it and screw it on.

- Lou

[Roy]

Has anyone put aluminum panels under the seats to cover all the tubing? It would be easier to carpet under the seats that way and not so many spots for junk to get caught in.
That's the way I look at it.

[AZPete]

Roy, I did.
http://i210.photobucket.com/albums/bb180/AZPeteCobra/seat%20floor%20covered.jpg (http://s210.photobucket.com/user/AZPeteCobra/media/seat%20floor%20covered.jpg.html)

[mikeinatlanta]

Hint for those wanting to use 10/32 screws. Rather than tapping each hole, just drill and use high quality self tappers (not home depot stuff). They will do a better job of making clean close tolerance threads than a tap. After the self tapper is in an out a couple of times you will have very clean threads.
Just make sure and use a good thread lube.

54568

[flynntuna]

Hint for those wanting to use 10/32 screws. Rather than tapping each hole, just drill and use high quality self tappers (not home depot stuff). They will do a better job of making clean close tolerance threads than a tap. After the self tapper is in an out a couple of times you will have very clean threads.
Just make sure and use a good thread lube.

54568

Were did you find those screws? McMaster didn't have them in that style.

[mikeinatlanta]

Local bolt supplier. What's more important is that you get quality American made. Cheap ones will break.

[UnhipPopano]

Putting a self taping screw back in can end up with a bad result. It is just as easy to replace the self tapping screws with regular screws if you need to take it apart. You can always use the self tapping ones somewhere else when the need arises.

[mikeinatlanta]

Putting a self taping screw back in can end up with a bad result. It is just as easy to replace the self tapping screws with regular screws if you need to take it apart. You can always use the self tapping ones somewhere else when the need arises.

Yep. I always replace the self tappers with 160,000 psi aircraft screws and a little anti-seize.