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Top 10 Ways to Drop Weight. I'll be waiting.


Crazycanuck

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I am getting near to building my Cozy MKIV. Within a few short months I should have an appropriate workshop. I am starting to get more serious about building my tool inventory and mapping out the project. After reading lots of material, reading the plans cover to cover twice, and getting the mod fever out of my system, I have come to agree that keeping the aircraft as light as possible is the best mod that one can do. Therefore, I am going to stick close to the plans but look for places to reduce the weight of my Cozy. Therefore, I would like to here everybody’s top ten list of weight saving ideas. What are the top ten legitimate ways to save weight on the aircraft?

 

Please note that I am already a skinny guy, so telling me to go on a diet is not productive. I am also a horsepower nut, so I am not interested in an 0-320 or anything of that sort.

Crazy Canuck

Toronto, Ontario, Canada

Cozy MKIV #MK1536

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Build it EXACTLY to plans. No electric noselift, minimal VFR instruments and stack, etc. etc. No Cozygoirrrls strakes or heavier matco 3 puck brakes. All this is if you are wanting the absolute minimal weight.

If you want to start adding 'comforts' like a elec noselift etc...you are making weight concessions.

Not many people have managed to duplicate Nats original empty weight of 1050#'s.

Self confessed Wingnut.

Now think about it...wouldn't you rather LIVE your life, rather than watch someone else's, on Reality T.V.?

Get up off that couch!!! =)

 

Progress; Fuselage on all three, with outside and inside nearly complete. 8 inch extended nose. FHC done. Canard finished. ERacer wings done with blended winglets. IO540 starting rebuild. Mounting Spar. Starting strake ribs.

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If anything, I need the extra weight in the nose (like electric nose gear) because I am also "skinny" and fly the plane solo a lot (or with wife and baby in back). This makes the nose real heavy---and thankfully, I do have electric nose gear.

 

I read that Ken Miller did a mod on someones Cozy to move the battery from the spar to the nose using quick disconnects when switching from solo to having someone sit up front with you----that will keep you from carrying quite a bit of lead with you.

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I am not an engineer but I wonder if Putting large lightening holes in the seats and lots of other areas like arm rest and covers and stuff like that could save a few pounds. I drill lightening holes in almost all the aluminum pieces I put in the plane. I have a manual nose crank and a straite mount 0360 they are lighter. Maybe if I leave the starter off and hand prop like I did on the old Longeze. My goal is to beat 1050 lbs but it is going to be tough I put Matco brakes in and they are heavy. I need to loose some weight but that is easier to loose than weight in the plane. STeve build on

Steve Harmon

Lovin Life in Idaho

Cozy IV Plans #1466 N232CZ

http://websites.expercraft.com/bigsteve/

Working on Chapter 19,21

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I called Nat about 8 years ago. The "1,050 pounds" was the weight of the prototype Cozy IV he built to prove out the plans. That weight was with minimal instrument panel; minimal filler and primer, (no paint); no interior paint; no consoles, rear seats, covers, and upholstery. No wheelpants. It also had the 4-sided, pointy nose.

 

I think I remember him saying the conformal Cozy IV -- the one he flew and displayed for years until he sold it -- was 75 pounds heavier. 1,125 pounds.

 

Here's my recipe for a light plane (not that I follow my own recipe)

 

1. Build as light as possible. This means remaining extremely disciplined about stippling, squeegeeing, and vac bagging (if you're THAT person) every_single_layup even when you're dog-assed tired after a 12-hour fab in a hot hangar in the middle of a hot summer.

 

2. Build as accurate as possible. A straight plane requires less filler. (Although the difference between "alot of filler" and "not alot of filler" may not be as much, or weigh as much as you think.)

 

3. Be realistic about your paint job. A gorgeous paint job probably weighs tens of pounds more than a minimal paint job.

 

4. Engine -- here's where you can achieve the single most weight savings. An O-320 weighs less than an O-360, which weighs less than an IO-360, etc. I have a friend of mine who started with an O-320 core and added some after-market parts and electronic ignition to it. That engine produces almost the same horsepower as a stock O-360, but weighs 45 pounds less!

 

5. Electronic Ignition, B&C Starter, B&C Alternator -- they all weigh MUCHO less than the stuff engine normally comes with.

 

6. Go Glass Panel Day VFR. EFiS systems are very light compared to the heavier 6-pack of gyros and instruments.

 

7. Avoid the add-ons for creature comforts. Electric noselifts, autopilots, trim systems, full radio stack, heaters, blowers, electronic fuel indicators, leather upholstery, pee-tubes.

 

Now, my PERSONAL opinions are that 1, 2, and 3 are mirages. A person will always TRY to build as best they can with the skills God gave them. Your SECOND airframe will weigh less than the first one you build. :) And everybody likes a pretty plane. 4, 5, and 6 are where you'll achieve the largest weight savings.

 

Item 7 -- ahh, the dreaded creature comforts. Some of us understand that this is (or will be) the only plane we ever build. We want to THOROUGHLY enjoy the plane, which for many of us means having those creature comforts that the rental planes we flew didn't have. Some of us feel that autopilots and full radio stacks help us fly safer. And after 5 hours in the plane, you're gonna wish you had leather upholstery and a pee-tube.

 

We also understand that a plane with all the creature comforts will be SLOWER than the lighter plane. So what? Go ahead and get there a minute or two before I get there. That way you can radio back to me and give me a PIREP of what the wind conditions are and what runway to use. (Wait, I already know that because I monitored your position reports with my high $$$ stack of radios. :D )

Wayne Hicks

Cozy IV Plans #678

http://www.ez.org/pages/waynehicks

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I am getting near to building my Cozy MKIV. Within a few short months I should have an appropriate workshop. I am starting to get more serious about building my tool inventory and mapping out the project. After reading lots of material, reading the plans cover to cover twice, and getting the mod fever out of my system, I have come to agree that keeping the aircraft as light as possible is the best mod that one can do. Therefore, I am going to stick close to the plans but look for places to reduce the weight of my Cozy. Therefore, I would like to here everybody’s top ten list of weight saving ideas. What are the top ten legitimate ways to save weight on the aircraft?

 

Please note that I am already a skinny guy, so telling me to go on a diet is not productive. I am also a horsepower nut, so I am not interested in an 0-320 or anything of that sort.

After reading the various suggestions for building a light weight plane, it does not appear that anyone has mentioned the temperature. I built my wings during the summer in my garage in So.Calif. The epoxy flowed like water and I know that resulted in very light weight wings. This was back in the late 1970's that the wings were built. This was using the slow epoxy hardnener on my Varieze. I recall that the temperature was at least 90 deg F.

 

After moving up to Washington state, many Variezes and Longs were built in a much cooler environment and suffered with higher weights. So if Mother Nature does not provide the heat, I would suggest that you turn the thermostat way up.

W.Johnson..........Varieze N725EZ

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Im with Wayne. Mines is a bit heavy but its comfortable and its a joy to sit in for 4 or 5 hrs on a long flight.

What makes it so!

 

Temperfoam in all seats. I could save 10lbs there

Two AP servos. 5lbs

Steel roll over protection 7lbs

Injection Pump and filter for IO360 4lbs

Fuel sump 3lbs

Forward hinged canopy (est) 8lbs

Electric nose gear 4lbs

Gear Fairings 2lbs

2nd Alternator 3lbs

 

And I probably have a bit of extra filler that I shouldnt as well.

 

Thats close to 50lbs. I could but wont take it out. Mine tips the scales at 1254lbs as it is.

 

That weight will allow a 4 hr flight with IFR reserves with 365lbs in the front 90lbs of kids in the back and 70lbs of bagage (if it fits) and still be 100lbs below MTOW. We are very comfortable, (as long as the bagage is well stowed), the AP flies, I listen to music and the kids watch videos.

 

Its a cruising machine and the extra items (weight ) makes it a great cruising machine. And its still not to shabby with one up and a light fuel load.

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Has anybody considered swapping out some of the steel nuts and bolts with titanium nut and bolts? Particularly I was thinking about the 6 bolts on the prop pressure plate. As a skinny guy any weight off the back would equal less ballast in the front which is a win on both ends. There are many websites that I have found that sell titanium fasteners and such for what looks like reasonable prices.

Crazy Canuck

Toronto, Ontario, Canada

Cozy MKIV #MK1536

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I'd definately go along with the idea of shifting things around so that with max front seat weight you have no lead in the nose, anything extra means you have useless lead as a passenger all of the time, what can you move forward?

...Chrissi

CG Products

www.CozyGirrrl.com

Cozy Mk-IV RG 13B Turbo

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For those of you who have or are planning on using the Infinity Retracts, you could swap out the heavy steel trunion pins with 7075 Aluminum pins.

 

This would probably save about 7 lbs total. I talked to JD about it, and he was adamant that AL wouldn't be strong enough, you'd need to use Titanium.

 

On the other hand, Paul Lee (http://www.abri.net/sq2000/11.html) flys an SQ2000 with copies of the Infinity Gear. His gear originally used 2024 AL pins for weight savings, but they eventually bent. He replaced them with machined 7075 AL pins and has had no problems since.

 

I might eventually go this route if I get my own lathe some time in the future.

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A good rule of thumb is that it generally costs about $100 and/or 5 hrs work to save 1 lb of weight.

 

For example, those 5lbs saved by machining 7075 AL trunion pins -- easily $500 in material & labor.

 

Or swiching to magnesium wheels for 1-2 lbs weight saving -- probably $200-300 price increase.

 

I might save a pound or two on vacuum bagging my canard, but that'll take at least a couple more hrs and cost $20 more in disposable vac bag material. (I'll do it anyway to get a stronger, better bonded part).

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How about the best of both worlds; stay out of the drive up window and save dollars and weight? :D

Alternatively, staying single will result in both a huge weight savings and prevent a lot of expenditures as well as a huge time savings!

...Chrissi

CG Products

www.CozyGirrrl.com

Cozy Mk-IV RG 13B Turbo

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I am considering moving the battery to the nose also. Would that not add considerable weight in running the battery leads though?

Yes, large cable will be required to run from the battery in front to the engine in the rear. So it is a choice as to what is most important in each particular case........extra weight vs CG. However, you may want to research how to use lighter weight material vs heavy cables. I recall that an award winning Varieze had used copper tape, but I can not recommend it or tell you to avoid it.

Burt Rutan originally stated in his Varieze engine plans showed to use two 1/0 cables if using a starter on a C-85. He later changed and deleted the choice of a C-85 with starter. However, since I had my engine by that time and also the heavy cable I used it. I do NOT have any voltage drop from front to rear! I expect a much smaller cable can be used. One should probably check on the amp draw on starting with the starter manufacturer. The weight of the cables will also increase the nose weight since a majority of their run is forward of the CG.

WT Johnson

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Marc has always been a proponent of keeping ones battery on the firewall, near cg, and out of the nose, thus not infringing on the front seat capacity by having fixed battery weight in the nose, but have MOVABLE ballast weight up there so that if you want to load up the front seat you can. (Hows that for a run-on sentence?)

I like that way of thinking.

FWIW.

Self confessed Wingnut.

Now think about it...wouldn't you rather LIVE your life, rather than watch someone else's, on Reality T.V.?

Get up off that couch!!! =)

 

Progress; Fuselage on all three, with outside and inside nearly complete. 8 inch extended nose. FHC done. Canard finished. ERacer wings done with blended winglets. IO540 starting rebuild. Mounting Spar. Starting strake ribs.

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  • 5 weeks later...

Now that Nat's plane has been sold, it would be interesting if the new owner could weigh it and report results...

 

Done. The current empty weight of N14CZ is 1107lbs (with oil).

 

Some extras include: electric nose-lift & wheel pants.

 

Has minimal "upholstery".

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To build at minimum weight.

 

1. Build per plans with mandatory plans changes only.

2. Don't hotwire cores, sand them out with a alum extrusion straight edge.

3. Don't add plies, or overlap beyond requirements.

4. Make your own cowl.

 

To reduce weight

 

1 & only: If not mandatory, throw the item up in the air, if it comes back down, it's too heavy to go in your aeroplane.

 

Myth: Squeegee resin for weight... Nope, that's to give good fiber-volume-fraction, and for nesting of fibers more than weight reduction...

Cheers,

 

Wayne Blackler

IO-360 Long EZ

VH-WEZ (N360WZ)

Melbourne, AUSTRALIA

http://v2.ez.org/feature/F0411-1/F0411-1.htm

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Wayne,

 

How does that save weight? I can understand getting better cores.

I hotwire mine at about 3/16 oversize and sand to the templates. This is what they recommend at Berkut. I think you end up with a more accurate core which results in less fill.

T Mann - Loooong-EZ/20B Infinity R/G Chpts 18

Velocity/RG N951TM

Mann's Airplane Factory

We add rocket's to everything!

4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done

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