DIY: plastic rear wheel skirts (Geo Metro)
 

plastic wheel skirts, attached with velcro. (EDIT: see update, June 21, 2008: now attached with brackets. Not because they fell off, but because they were too hard to remove.)

why plastic: lightweight, non-rusting, easy to work with.

why velcro: i didn't want to drill any part of the sheet metal in the wheel well, because it's one of the most rust-prone areas on a car, and ontario is in the rust belt.

that said, drilling and using some other kind of fasteners would definitely be faster and probably easier. also, metal would be fine, or if you're good with fiberglass. the basic layout/planning steps will be similar.

supplies:

http://ecomodder.com/forum/attachmen...1&d=1325541394

- black krazy karpet ($2 ea., 1 per wheel)
- 1 in. wide velcro strips (free - junk drawer)
- tube of sticky silicone-type glue/sealant ($4)
- newspaper
- cardboard
- scissors
- duct tape
- aluminum strip ... the thing that goes across a doorway to trim the transition between different flooring materials (free, in workshop - 1 per wheel)
- not shown: heat gun

btw, for those not familiar, this is what krazy karpets are usually used for! crazy ***, psycho-slipperly fast, unsteerable fun on snowy hills.

many an injury has been caused by these things, including yours truly, whose karpet ended up in front of me in a childhood crash, and its thin edge jammed into my face between my lip and nose and carved a nice gash. krazy!

http://www.youtube.com/watch?v=hYhEsQekd9Q

step 1:

tape newspaper over wheel well. try to make it taut and wrinkle free. trace wheel arch outline.

http://ecomodder.com/forum/attachmen...1&d=1325541394

step 2:

use the arch tracing to make up a cardboard prototype. when cutting the cardboard, don't cut right to the edge of the tracing. you need extra material to fashion the curves to get around the tires and leave space from the wheel. and depending on your attachment method, you may be forming a 90 degree lip as i did, to mate to the lip in the wheel arch.

take your time getting the cardboard shaped right. probably the most important area is the lower part of the arch. the length of the skirt material here determines how much room you'll have to fashion the right curves and leave enough room to clear the tire & wheel/cover.

http://ecomodder.com/forum/attachmen...1&d=1325541503

step 3:

making the plastic version...

- i cut the velcro into 1/2 in. strips, lengthwise, glued one strip to the wheel arch lip (inboard as much as possible), and the other in sections to the corresponding "tabs" which make up the lip i cut & formed in the plastic

http://ecomodder.com/forum/attachmen...1&d=1325541659

step 4:

making the plastic version, continued...

- to give the plastic some rigidity and to hold the proper shape to clear the tires/wheel covers, i taped, then drilled and attached 3 screws through a strip of flat aluminum trim on the back of the skirt. (the trim is what you find on the floor in a doorway at the transition between different flooring types.)

i dremeled off the extra length of the middle screw to keep it from touching the tire/wheel cover. (the side screws are ok like that

http://ecomodder.com/forum/attachmen...1&d=1325541765

step 5:

that's it. i didn't have to paint my skirts because the black plastic is a fair match for the paint (a coulple of shades lighter). fyi, the skirts don't look quite as nice as the pics suggest, but i'm happy overall.

the only thing that needs paint are the screw heads. a couple of dabs of black will hide those.

i used the heat gun to soften the plastic enough to form a character line at the bottom of the skirts that continues a line above the rocker panels.

http://ecomodder.com/forum/attachmen...1&d=1325542162

time to complete:

4 to 6 hours.

velcro notes:

i'm confident the velcro is going to hold the skirts in place in all normal situations. the only thing i wouldn't do is subject the gap between skirt & wheel well to the blast of a pressure washer.

the velcro is tricky to get into place when finally installing the skirt without it sticking where you don't want it to. one way to get it done is stick tape loosely in sections on the velcro - so you can get stuff into position, then pull the tape out and press the velcro together.

there's just enough room beween the wheel and the skirt that i can reach my skinny arm up behind and press the "tabs" firmly in place.

the adhesive i chose to stick the velcro to the car and the skirts wasn't the best - it's not strong enough. i won't be able to remove and re-install the skirts frequently or i'll be pulling the velcro off. one way around this is using a thin putty knife or screwdriver to separate the velcro, rather than just pulling on it when taking the skirt off.

Feedback from the wild...

Sitting at a stop light, a guy in a purolator van pulled up in the next lane and yelled over "what's that cover over your rear wheel for?" i told him, and he said "so you burn less fuel? cool!" and he drove off.

Made me wonder if he's looking for ideas to save fuel. Companies sometimes reward employees who suggest ways to reduce costs. i guess if we start seeing wheel skirts on purolator vans, we'll know the answer.

Update:

In retrospect I learned: the plastic I used is too light. It wasn't an issue when I made them when it was cool outside (and the plastic was stiffer), but in the peak summer temps it got much softer and the skirts were pretty ... wobbly. I need to glue something on the backside to stiffen them.

If I were making another set (still haven't done my front wheel tests http://www.gassavers.org/images/smilies/smile.gif ), I believe I'd go with fiberglass.

Update 2:

My beloved wheel skirts have been off the car for most of the summer.

When I took them off late last fall to have the car rust treated, a lot of the velcro came off too, despite trying to be careful. I duct taped them back on for the rest of the winter, but pulled them off entirely once the tape started disintegrating this year.

I need to:

1) add a coroplast backing to stiffen them (the krazy karpet plastic is too soft in hot - ie. 25+ C - weather

2) make clips / fasteners to replace the velcro

I got a good start on "1" over the weekend.

Ya Might Try
 

For a Glue for your velcro you might try some 3M weatherstrip Cement. It ought to do the trick. And have ya thought of just applying some fiberglass to the back of your plastic? And maybe laying a small dowel rod on the plastic first as a strengthening girder? And as for drilling and rust... drill, and then dip your screws in paint before you thread them in, that ought to keep the rust out. Just a thought. John

Why not drill the required holes then spray with underbody coating(entire wheel well) the dip screw in the same stuff and then attach. It'll be a b!tch to remove but it'll hold like nobodies business. I agree with you about inserting small metal rods shaped like the skirt and then plastered there with fiberglass, the only problem it would possibly cause is if it detaches due to flex, maybe using some sort of harder plastic strips to secure to the back for support without the possible tire puncture issue.

hot????
 

hot - ie. 25+ C Now that's crazy talk! we rarely drop below that on a cold winters day, a hot Summers day here is more like 40+ C. I guess I can't use krazy karpet then.

Thanks for the ideas though, I will have to come up with something else for my plastic stock.

Dave.

Well, considering you need SNOW to be able to buy Krazy Karpets anyway, it's looking like a moot point! ;)

You might want to look at AndrewJ's method. He used thicker ABS for his skirts, if I'm not mistaken. http://forum.ecomodder.com/showthread.php?t=312

Actually that was the first post I read in this site, also very inspirational, I especially liked his mounting method, been thinking that over....

Snow, I've heard of that, it's that white stuff on Christmas cards from way up north :-D
Seriously though I have seen snow, I just choose to move to a warmer climate for health reasons.

After this season, I've been thinking of moving to a warmer climate for mental health reasons.

Yeah me too.. Actually i recently bought land in Texas.. rarely gets below 32 degrees.. :)

I have a late model car ('06 Civic) and I just can't see me putting anything on this car that I made myself.

I'm waiting for a quality-made kit I can buy that has:

1) 2 rear wheel skirts (preferably painted to match)
2) solid wheel covers (at least 2 for the front)
3) a better / lower front splitter (the rubber piece that goes under the front bumper.

The DIYer part comes in when I fasten the bits on. ;)

I just finished Rear Wheel Skirts v. 1.5

Skirts have coroplast backing for added stiffness (think I mentioned that somewhere up the thread already).

And they're now attached to the wheel arch with 5 home made brackets that were installed without drilling into metal. The skirts can be removed/reinstalled in about 30 seconds. The downside is there are now 5 screw heads around the rim of the skirt - which don't look too bad.

I'll post new pics tomorrow.

Pics, pics, pics:

First of all, here's the back of the skirt with the coroplast attached (contact/rubber cement) to stiffen it more for those hot summer days (when the black plastic was getting pretty soft & wobbly):

http://ecomodder.com/forum/attachmen...1&d=1214175313

Next, on to the new non-drilling-the-car attachment method. A crummy shot of the DIY bracket. It's made from flattened copper pipe, stainless nut, bolt & washers:

http://ecomodder.com/forum/attachmen...1&d=1214175313


Next, the same bracket, shown installed. Another crummy shot - sorry:

http://ecomodder.com/forum/attachmen...1&d=1214175313

I made 6 of those special brackets in total, 3 per side. Once tightened, they're well clamped down and very solid.

The other two brackets per side attach to the lip of the plastic bumper, so I just made simple 90 degree bends in the copper pipe, drilled & bolted them on:

http://ecomodder.com/forum/attachmen...1&d=1214175313

And here's the skirt installed. I'll probably paint the screw heads black:

http://ecomodder.com/forum/attachmen...1&d=1214175313

YES, those are mud flaps on the back wheels. (*hangsheadinshame*)

They serve as a mounting point for the aft end of the skirts (without them the curvature to bring them all the way to the bumper would be so much that I believe flow would detach anyway).

I'll probably trim the excess off now that the final skirt installation is done.

http://ecomodder.com/forum/attachmen...1&d=1214175983

Did you trim off those flaps?
 

I took my rear flaps down to my shop so I could use the belt sander to clean off the edges I cut with a Stanly knife.

http://ecomodder.com/forum/36034-post25.html

I think they are going to be a good mounting point, if I ever decide my CRV should be wearing skirts. :cool:

I really like the copper clips you made. Does that type of clip have a name? Can you buy clips like that anywhere? My tools are not cooperating with me right now, and I could really use clips like that!

So you smashed a copper pipe? Is that 1/2"? How did you drill the holes in it? (I mean what kind of bit?) I tried using copper pipe straps, but it was a lot of work, and they weren't tough enough to hold anything.

Not sure if there's a name, or if you can buy them.

Yes, I flattened a 1/2 inch copper pipe with a hammer and drilled it with a regular bit (copper is pretty soft).

PS - aside from the exposed screw heads offending some people's aesthetic sensibilities, the clips are great. I had the car rust treated earlier this month, and the skirts come off / go back on in less than a minute with this setup.

Did you see much of a diffrence in MPG? By that I mean not a 10 or 15 mile trip, I mean a 200 mile tankfull compared to a 200 mile tankfull?

That is a very good looking rear skirt. I may just have to try that project. I see your rims have the slots filled. How was that done? Have you made a post on the steps for doing that? I think my Fiero rims would be a good candidate for that.

HA! I figured out last night why my "copper" clips were such a hassle to make... when a magnet grabbed one (DOH!) Yeah, I never remembered copper being so uncooperative before...

Really, I just think those clips are the best thing ever. They would solve so many problems I run into.

I'm considering other schemes... like maybe magnets. Or those snap-in things that hold mud flaps on. All seem to come with hassles, but I'm hopeful.

Speaking of magnets, I highly recommend experimenting with neodymiums as an absurdly easy way to attach pizza pan wheel covers. I tried it, and it would totally work if the pans fit better on my rims. (I'm like a millimeter off) That would be a $5-and-5-second racing wheel install, if you're lucky.

I measured a 2.9% improvement @ 59 mph / 95 km/h. Though it wasn't very rigorous: Testing grille blocking & wheel skirts: +5.7% improvement - MetroMPG.com

Also see: http://ecomodder.com/forum/showthrea...skirts-87.html

FYI, rear skirt effectiveness won't be consistent across different cars. It depends a lot on how close the rear arch is to the rear of the car (my opinion is that the closer the wheel is to the corner, the more a skirt will help); the size of the tire/arch gap, wheel cover style & other factors.

I just cut out some thin plastic shapes and glued them to the wheel cover. 2 of the shapes have since come off (wrong kind of glue).

I'd be very worried about having the steel near the copper disappear from galvanic corrosion, especially if any road salt is present.

The stainless bolts that squeeze the brackets onto the wheel arch lip may be subject to corrosion, but the car itself should be OK (I didn't break the paint to use this attachment method, which was the original goal after all).

The skirts do come off at least once per year for inspection and pre-winter rustproofing.

I just went back through the list of mods to get here (I do this every so often, to keep them fresh in my mind... lest we forget...)

If you took those clips back off, and put some shrink wrap over the sections that touch the car's sheet metal, it would prevent any chance of galvanic corrosion, and help prevent the copper from wearing through the paint due to vibration. Plus, they'd have that much more of a friction coefficient against the sheet metal, which might promote an even better hold. And it would only take like 30 seconds per side.

I need more posts so I can see the pictures on here. I have a 1999 Metro and have done a grille block and a lower front spoiler. I had initially completely blocked the grille but have since removed just the one small section in front of the radiator. Since I had only recently just got the car I can't determine exactly how much my mileage has improved. My last two tanks I got 49.1 and 48.9 average. Next up are rear fender skirts and belly pan.

This is really a awesome mod, going to do this over the weekend now :) Working my areo now that I went with a XFI trans/cam and 13" wheels :D

Did you get a chance to work on your skirts?

I wish I had seen this before I started installing my wheel covers. The adhesive backed velcro did not hold mine on very well. There are two on the side of I-44 between here and Oklahoma City. :( Now parachute cord (550 cord) has worked very well holding corroplast covers on. I also made some partial front wheel skirts from corroplast and used the factory screws that hold the wheel well liners in place. They held just fine. The pictures from page 1 aren't showing up for me, but my full skirt plans involved using some small L brackets to hold some plexiglas/LEXAN in place, using the same wheel well liner mount points.

how do your screw stay in place in the DIY copper thing (the screw that keep the skirt in place) ?

The copper is fairly thick - lots of material for the threads of the screws to hold.

Darin-Is there a chance you could post or re-post close up pics of your wheel skirts? The pics won't show up on the first page and I've been dying to see them.
Thank you!
Barna

Reposted the pics in the first post of the thread.

Let that be a warning to you folks: don't use a 3rd party image hosting service. Some of them disappear... with your photos!

Upload your images to your EcoModder album, or as attachments.

thanks for the re-upload!

where do you pick up your c-plast?

Home Depot here (only carry white).

I got some at Regal Plastics in Oklahoma City. I've also ordered LEXAN from Rid Out plastics online... Found both using Google.

Yikes! I'd thought of that, and my account on Imgur is an unsorted mess. That's good to know—I'll look into this Ecomodder album thing. Can I redirect old links into it?

Not sure what you mean by "redirect old links".

If you mean go back and edit old posts to replace the image links with links to moved images, then "yes". That's what I had to do in this thread after the image hosting service nuked my pics.