Honda Insight Tail Extension Project

[Weather Spotter]

I learned this a long time ago:

Water always wins. We just hold it back for a while.

[COcyclist]

Jim, Thanks for the updates, even the setbacks you have suffered. We are all here to learn from each other. You proved that the concept works and I am sure we will see the improved v1.2 in the near future.

I hurriedly left a small gap on both sides of my belly pan ahead of the rear tires and it filled with snow and ice that I had to dig out by midwinter. We do have to build for real world conditions.

[orbywan]

Hi Jim,
I just read your thread on your belly pan and your boat tail. I’ve been fabricating ‘things’ for about 45 years now I have to say when I first saw all the foam and wood I thought this guy doesn’t know what the hell he’s doing. Reading further reveals some of most incredible patience and craftsmanship I’ve seen in a long time. I just got into aero mods about six months ago so I’m miles from experienced or expert, but your craftsmanship on these two threads shows skill beyond everything else I’ve seen.
I just built a boat tail for my 25 foot RV. I was slightly annoyed it took three weeks to build, mainly because of the 110 degree heat in the shop in the afternoons. Now I feel like an impatient idiot, but that’s OK, the point is I took the bull by the horns and did it. Next up is the belly pan, which will not come close to what you did on your Insight, but it will be an improvement over nothing hopefully.
Keep up the good work, I can’t wait to see the final product. I did show quality paint jobs and restorations in a former life, OK, decade, and I know how time consuming and painstaking doing a quality paint job is.
When I get the shape of my boat tail finalized, I was going to skin it with aluminum, but you’ve got me thinking about fiberglass. When you have some spare time (Ha!), could you look at my ‘Aero RV’ thread photos and see what you would recommend if I was going to cover that with fiberglass? The steel cage is necessary for strength because it so big, but a friend suggested smoothing out the pop rivet divots, covering it with mold release and shooting it with fiberglass shot to make a mold. That sounds way expensive and time consuming. Could you take a look and see what you think? Thanks in advance.
I also have a suggestion. When you reach the point where you are happy with the boat tail, finish and all, why not send several photos to Honda, tell them what a great car they build, and suggest they build them like yours! When a little guy like you can tell a behemoth like Honda that you have truly improved their product in a major way… I can’t think of a better complement to your skill and labor, other than inspiring other clods like me to give some of these things a try. Great work!

[3-Wheeler]

Originally Posted by orbywan

.....Keep up the good work, I can’t wait to see the final product. I did show quality paint jobs and restorations in a former life, OK, decade, and I know how time consuming and painstaking doing a quality paint job is.

Your tail is one of the more impressive projects that I've seen on EM, so very nice work.

Yes, getting all the smooth surfaces takes a lot of time, and that's basically what I have right now over the summer. My shoulder is still pretty sore from the bike/dog accident and I limit myself to microballoning and sanding surfaces on the tail.

Originally Posted by orbywan

.....When I get the shape of my boat tail finalized, I was going to skin it with aluminum, but you’ve got me thinking about fiberglass. When you have some spare time (Ha!), could you look at my ‘Aero RV’ thread photos and see what you would recommend if I was going to cover that with fiberglass?

Well to be honest, I would not cover coroplast with epoxy and glass cloth because I'm really not sure about the adhesion qualities between the two. I know Coroplast is a plastic product, but if it is anything close to the Polypropylene line of plastics, hardly anything sticks to it. If Coroplast is closer to the Nylon line of plastics, then you may have a better chance of things working long-term.

I have noticed over the years, that epoxy sticks very well to wood and itself (epoxy), but most plastics can bend enough to allow the epoxy to easily delaminate.

Originally Posted by orbywan

.....The steel cage is necessary for strength because it so big, but a friend suggested smoothing out the pop rivet divots, covering it with mold release and shooting it with fiberglass shot to make a mold. That sounds way expensive and time consuming. Could you take a look and see what you think? Thanks in advance.

Covering the entire surface of your tail with epoxy/fiberglass in multiple layers thick enough to support itself, would as you suspected, be very costly and heavy.

At this point I think a better approach would be to make the entire tail shape in 2 inch thick foam and fiberglass it as you build the shape further from the back of the RV. This would be similar to what I did on the car.

I would think that you would want to build the entire tail in such a way as to make essentially four panels that can be unbolted and removed from the rear of the RV, one at a time, so that you can *easily* assemble/disassemble the tail for final fiberglassing/sanding/priming/painting and any maintenance that might be needed. Just my thoughts.

If you happen to take this approach, I would also consult the AeroHead Streamlining Template for a smoothly curving arch that follows that overall shape for the most aero efficiency.

You would end up with a very smooth surface, very light and strong, and *assuming* it's sealed properly from the elements, last a very long time as my motorcycle fairing has over the years.

As for working with foam/fiberglass, I would highly recommend purchasing the Mike Arnold DVD for construction of his AR-5 airplane. Mike is even more of a artist than I am. Truly inspiring work! And he gets into many details of working with foam/fiberglass systems.

Originally Posted by orbywan

.....I also have a suggestion. When you reach the point where you are happy with the boat tail, finish and all, why not send several photos to Honda, tell them what a great car they build, and suggest they build them like yours! When a little guy like you can tell a behemoth like Honda that you have truly improved their product in a major way… I can’t think of a better complement to your skill and labor, other than inspiring other clods like me to give some of these things a try. Great work!

That sounds like a great idea!

Jim.

[orbywan]

[QUOTE=3-Wheeler;251710]Your tail is one of the more impressive projects that I've seen on EM, so very nice work.

" Well to be honest, I would not cover coroplast with epoxy and glass cloth because I'm really not sure about the adhesion qualities between the two. I know Coroplast is a plastic product, but if it is anything close to the Polypropylene line of plastics, hardly anything sticks to it. If Coroplast is closer to the Nylon line of plastics, then you may have a better chance of things working long-term."

First of all I’m not sure how you do the multiple quotes within the same text so bear with me please. The suggestion was to use the coroplast as a base for making a mold, not being a permanent part of the structure. I'm not real keen on that anyway. As far as using foam and glass to build the whole structure I'll have to give that some thought.

The next thing I need to do is finish the belly pan and find out how accurate my first results were. If the results are as good as first indicated I’m not sure if I should change the shape of the tail or not, why mess with success? How positive are you that following ‘the template’ would improve the results and would you hazard a guess as to how much? I would drop the bottom ramp area for sure, that area is not flowing well at all. Everything I’ve read indicates that the bottom will not flow properly unless the belly pan is complete but the angle on the bottom is way too steep regardless.

That is a pretty large area, if I did rebuild it from foam and glass I would still build either a steel substructure or brace the heck out of it. That would make it possible to put a factory grade finish on it, but unlike yourself, I’m not sure I have the time and patience to put in the man hours to achieve that, the actual surface area is about the size of a small car.

All of this brings up the quandary all ecomodders and builders face. How do I accomplish what I want to do in the most efficient way possible? I was serious about sending photos to Honda, and come to think of it, all the car manufacturers, and show them the numbers of people responding to your build, and maybe they will consider the fact that the public is finally ready for some serious aerodynamics on their vehicles. I think and hope that’s a true statement. Anyway, thanks for you input, it is greatly appreciated!

[jime57]

Visited with 3-Wheeler today in southern WI for a first hand tour of the boat-tail project, and some good conversation. He has produced a truly high quality result and soon as he irons out a few minor kinks, I think this is going to be a very impressive build. He is slowed up a bit right now by his injury, but his spirits are high and I think that he'll have the tail finished by summer's end. His technique, though more time consuming than some alternatives, produces a very strong and lightweight result. Thanks Jim!

[Cd]

Any new pictures of the car ?

[3-Wheeler]

Originally Posted by Cd

Any new pictures of the car ?

Hi Cd,

Almost.

About two months ago, I sanded off 95% of the Bondo Spackling Putty, as I have now found out that it's adhesive qualities are questionable on fiberglass. And there is a picture I took off a 1 inch diameter flake ready to fall off during the sanding operation.

Next came one month of adding epoxy/glass sphere mix to the entire surface and smoothing it out again. It took me about two weeks to figure out how to properly work with the stuff since it is so different than body putty.

Two weeks ago, I started adding gray primer paint. There are probably five coats applied, with most of it sanded back off.

I spent the entire day sanding two heavy coats of gray primer paint with 60 grit wet sand paper. A lot of work, but the finish is slowly getting smoother.

Just finished glassing the under side of the tail today as well.

The weather is quickly getting cooler so the tail should be "completed" for winter's driving.

No red paint yet, as several spots have already "bubbled" from the sun's heat on the gray paint, which I would guess, gets about 150F with direct sunlight on a hot summer day. Too hot to hold your hand on very long.

One bubbled section was about 2 inches in diameter and when I cut the fiberglass away, what did I see? A nice patch of spackling that swelled up!

Note to self: DO NOT USE WATER BASED PRODUCTS ON HIGH QUALITY AUTO BODY PANELS. Well to be honest I have never had bad luck with Elmers Glue on foam projects in the past, but the Spackling has kicked my butt twice now. Both times swelling up beyond it's normal "dried" dimensions.

At least the primer paint is automotive quality at $35 per quart. Don't forget the hardener ($35 per quart). The paint will take days to setup without it. Don't ask me how I know.

I can actually sand with my dislocated left shoulder now. It really helps to have almost two arms again.

I'm hoping to get the tail back on the car in about a week or so.

Jim.

[HighMPG]

3wheeler!
Great build and love the architecture on your rear end! lol
I was looking at a insight the other day on craigslist but I want to keep my budget under $4000. Again thanks for the pictures and story.

[eMax]

So how's the car looking these days? I just read through this whole thread and I'm craving more updates!!