Lynn Erickson

I just discovered that Fisheries Supply in Seattle sells Pro-Set epoxies. I have a commercial acct there which gives me a pretty good discount so it's $93/gal for 125 lo-viscosity resin, $74 for 135 med-viscosity (but they're backorderd on that), and $50 ea 229 med or 226 fast hardeners. You can blend these.

 

The 135 is back-ordered but the 125 is on the shelf. On the shelf is good.

 

Also - Just bought 3ea 48x96" sheets of 3lb Divinycell for $223+tax.

Thats a good deal.

If you are going to use 125 resin, stay away from the 229 hardener because it requires a post cure to get a complete cure. the 125/226 will room temperature cure. the 125/226 has a 3 hour gel time and you do not need any longer then that.

This might be a trivial point, but given the surface areas we are discussing here, what is the weight difference between both techniques? I recognise that Lynn's approach requires less effort (you get flying sooner) with no difference on quality of finish, but is the trade-off an increase in weigh, and if so, how much? How much heavier are these hi-build primers compared to dry'ish micro?

Merry Christmas all,

 

Bruce.

they are not heavy and the idea is to use dry micro and get the surface as true as you can with a course sand paper. meaning the surface is true but has 60 grit scratches and pinholes. use the high build to fill the scratches and pin holes leaving a smooth uniform layer of the primer. most of the new two part epoxy primers come in a high build and regular formula.

Hmm, I've never found it that hard to do: When the surface is relatively flat, rub it with an 18" (or so) aluminum bar. It will leave smuges on the high points (the same high points left after completing your 60-G sanding). Gently sand the high points and rub with the bar again until the smudging is uniform. Now you'll have a flat 320G surface ready for pinhole-killing.

Its not hard to do on the relatively flat surfaces with a straight edge. I want to see that 18" straight used to do the compound curves, or better yet the inside curves. my point is that it is not necessary to go to 320G to get a true flat surface when using the high build primer, they recommend only go to 220G so there will be good tooth for it to adhere. sanding the surface down to 320, adding epoxy and then sanding it again before primmer is adding extra steps that are not needed. this all happens in one step with the high build primer

So Lynn, you don't subscribe to the Cory Bird method at any stage of the finishing process?

no. it is just not necessary with the new high build epoxy primers. the problem with the method is that the surface needs to be really true before you put on the raw epoxy. if it is not true and you will not know until you prime and then what do you do ? add more filler or try to sand through the coated filler and then coat it again. I developed a similar process long before Cory was born and it does work. used it on my canard and then did the rest of the plane with high build. the new stuff just cuts out the extra step and it sands a lot faster with no pinholes. the stuff is designed to go over molded carbon/epoxy parts and you can't have more pin holes than that.

Sanding is sanding. Either "waste time" sanding filler or waste time sanding high-build primer.

 

Sanding the filled surface from 40G to 320G also requires less high-build primer and results in a lighter airplane.

 

What's the logic in purposely leaving deep scratches in a surface so you have to use high-build primer to fill them?

first I said to sand to 60 grit not 40. 60 grit scratches are not very deep and will fill with one coat of high build.

second high build primer does not weigh any more than micro

And who said anything about leaving deep scratches in the surface.

If you try to sand the micro to 320 you will have a very hard time keeping the surface true. the soft micro will sand away much faster then the hard glass and you will leave a wavy surface. sand the micro with the course paper until you start to see glass and stop. fill any low spots and repeat. when all the low spots are gone, apply high build and sand to 220. then prime and paint.

It's way more work to finish a 36-grit surface rather than something like 320-grit surface. Epoxy will stick just as well to either one but 36-G scratches are the Grand Canyon of scratches. Even 120-G sounds too coarse to me as a final surface before to starting to fill pinholes. I'd try to get it to at least 220-G if you can do that without sanding into the glass. For my next paint job, I will try to get to a 320-G surface before going to the straight epoxy pinhole filling.

thats a waste of time to sand the filler more than 60 grit. The epoxy is to fill the pinholes and then use high build primer to fill everything else. actually the epoxy is also a waste of time the new epoxy high build primers are the way to go. fills the 36 grit and you end up with no pinholes. we did a Lancair IV with a carbon fuselage this way and did not have any pinholes

I'm planning to use this technique on a surface which I have filled & sanded to the shape I want, and it is quite smooth (maybe 120 grit or better). If I try to rough it up with coarse grit at this point, the sandpaper will take more out of the filled areas than the glass areas, and that would change the shape.

 

Is the 36 grit finish intended to avoid unnecessary fine sanding since the epoxy will fill the grooves anyway, or is it required in order to provide more surface area for improved adhesion?

 

Joe Polenek

the 36 grit finish intended to avoid unnecessary fine sanding since the epoxy will fill the grooves anyway

mm and a 4 blade? I have a MT 4 blade on my newest toy (a cosy classic) the MT is white and the soot looks especially nasty on it, any idea how I could clock that one (classic 4 exhaust end of cowling)??

wolf.

Anything with that may blades will always get some of the blades very dirty. paint it black. why did you go to a four blade prop?

is there washout in the cozy wing ?

if you order a flat wing will the washout still be there ?

what is washout in a wing ? and is it twist ?

will i have it in my cozy and how do i check it ?

is there other places to look for my answer's ?

Yes, the water line on the templets take the wing twist or washout into account. when you level the water lines when fastening them on the foam blocks you are building the washout into the wing. if you want to see how much, lay the templets on top of each other with the water lines lined up and you will see the angle change. the more outboard, the more the leading edge is twisted down. as the angle of attack becomes higher the inboard section will stall first because it is at a higher angle of attack then the outboard section. this keeps the ailerons flying while the inboard section stalls, making the plane more stable and controllable during the approaching stall. not sure what a flat wing is but if you mean a straight trailing edge, yes there is still is the same amount of washout or maybe even a little more twist to the overall wing.

I just passed the stupidity-test and did the same thing - i.e. mounting the aft landing-gear bulkhead with the plies facing backwards. Just curious to know - before I hack them loose again - why does it matter what side the 8 plies are?

Yes, the extra plys take the shear load of the bolt. if there is space between the landing gear tab and the extra plys there will be a bending load on the bolt. not good

Hi DanPilot91 and Snoopy,

 

Thank you very much for your reply. I would very much like to have the original seller's information. Snoopy, sadly enough I already traded for the plane this past weekend. You guys are right it is VERY rough, but I didn't have much money in the gyrocopter. As long as the plane IS repairable, I'm not too disappointed. The wing mounts didn't show any corrosion, but the fiberglass is not very good at all. I expect I will have to replace significant portions of the fiberglass on the fuselage and wings. Do any of you guys know anyone with a set of used plans I could purchase, or information on reskinning one of these planes? Also, do you guys recognize the engine mount from the ebay pictures and have any idea what kind of engine it might have had?? Any and all help will be greatly appreciated!

 

Sincerely,

 

Robert

Looks a bit rough but many variezes did and flew fine. some of the building techniques in the olden days were not as refined as today. looks as if it did fly.

before you panic and tear off a lot of glass you should have it looked at by someone who has built and flies one. it may not be all that bad, some time they just look bad because of the paint. We just completed a repair on a vari old Vari that was crashed landed for the second time back in april where the all the landing gear was torn out, the nose broken off and the canopy broken. it will fly again this weekend. any thing on these plans is fixable and will take a lot less time then starting from scratch. good luck on the project. and a smart trade by the way

So basiclly I just fill out the 8130-12, submit it and if they ask any questions explain that I regret the fact the the movers seem to have lost the box that contained my photos and logs for project.:cool:I think I'm starting to understand the process. They would like to have them, but If I can't produce them due to circumstances out of my control all they have is my notarized statement and that will work.

What an Plane? did someone say Airplane? Does that guy really thinks he can build his own plane that flys?

Now you are getting it. all you want to do is fly your plane. and you would think they would want to help. its their job. The FAA guys get paid one way or another. but the DAR takes your money so you can fly. Besides not everyone building an airplane can afford to own their own camera and take pictures of their project. you have to make choices when building, a used Brownie camera or a new Lightspeed Zulu one headset. That, any airplane guy will understand. I like, they got buried with my grandmother. no one would want you not to fly just because the pictures of the plane lay in piece with Granny. now that I think about it, maybe it was the camera thats buried with Granny.

Ok everyone, I went to visit the faa today to find out about registering my Varieze and was not happy with what I found out. As stated before I have an airplane that was abonded and no info came with the plane ie.. data plate, n number, paperwork, or plans. It has been determained that I have a rebuildable project by other Eaa members and builders. #1 one I need some sort of prof of ownership and apparently receipts for any building materials is not sufficient. #2 I need a builders logs and pictures and possibly video of the the bulid, now I have been recording what I have done to the plane and Its going to need quite a bit of work to get it done. But I was told that it wont qualify for the 51% rule in which I will be the ultimate builder and able to perform all work and maintenance myself. They told me that I have to be the one that built the fuse, wings ect. I told the FAA well if I did all of that, then I would be 100% builder. After all according to FAR 21.191(g) "Operating amateur-built aircraft. Operating an aircraft the major portion of which has been fabricated and assembled by persons who undertook the construction project solely for their own education or recreation."I am mearly another particapant in the build of this airplane and there for, I feel that with as much that is is left to do I deserve to be the reg. builder if I finish it. Some of the builder assist programs do not require as much participation as what I will have put in this plane when it is finally complete. So whats your take on the the subject? Am I missing some loop hole here?

first mistake you talked to the FAA. but you know that now. and those pictures that you had of the beginning of the build. you know the ones that got burned up in the fire. and the others that were looted from the house after the fire. with the receipts. the only way they know it was not owned by you is because someone told them. to bad you don't remember the name of your partner on this project. you know the one that you have known all your life and is now deceased. the same one that they would not know about unless someone tells them. so the local FAA knows about a vari eze that has no owner and some guy is trying to get it registered. I don't think they know about the new plane that someone and their wife build over 51% of called a eze vari. the one that they are trying to register in their wifes name with the help of an out of state DAR .

Yeah, I knew that would stir the pot. I wasn't planning to use bolts from Home Depot.

 

Mcmaster-Carr sells Mil-spec 150,000psi bolts with an "Ultra corrosion resistant" coating that's supposedly many times more corrosion resistant than cadmium plating. They are 1/3 the price of the same size AN bolt at Wicks.

 

Grade 8 bolts are used in high-load applications. They bolt flywheels onto crankshafts for example, bolt the reciprocating internal parts of an engine together, and are used extensively in automobile suspension systems, which routinely see shock loads way in excess what an aircraft will experience in flight.

 

Any system is only as strong as its weakest link...and I'll submit that the 150,000 psi bolt that is holding together your PLASTIC airplane aint gonna be it.

 

But...to each his own. Thats why you have to paint that word on your plane. (the X word)

yes they do have bolts that are stronger in there own way. but try to buy only one of those bolts from Mc master. if you have to but ten to get one it won't be that cheap. and try to get bolts in 1/8" increments with the short threads that AN bolts have. and they don't tell you the grip length of the bolts and they don't have bolts that come in 1/8" grip length increments. without the correct grip length you will have threads in shear or a lot of thread sticking out of the end of the nut and thats not the way it is done in aircraft for structural reasons. do the bolts come with safety wire and cotter pin holes drilled in a bolt with the correct fine pitch thread, NO. yes you could drill the holes yourself but then you loose the ultra corrosion coating. there are not that many bolts in our plastic airplanes to make it worth going the cheap route, you might save $100 on a $ 60,000 aircraft and most of them hold on things I do not want to loose during a flight. but if you have a better and cheaper way then anyone has discovered in the last 100 years of aviation have at it.

Sent my elevators and ailerons to an experienced painter (didnt have the patience or shop to do it myself). Before painting all control surfaces balanced nose down per the plans.... Well when I retrieved them from the paint shop and checked them again.....all were tail heavy. NOT GOOD... a show stopper. TOO much paint.

 

Solution Options :

 

1. try adding the .3 pounds of lead to them

but if that fails I guess my options are to:

 

2. Sand off all the paint and filler and re-apply sparingly. (paint included) $$$

3. Build all new ones (Big bummer).

 

Is my logic sound .....???

 

Please help this poor 10+ year builder.

 

KS

many builders have had this problem. first try to rebalance by taping on some weight and see if it will work. the plans state how much is acceptable. do your ailerons have the 3/8" or 7/16" steel rod as a mass balance weight. the long ez plans used 3/8" rod and the cozy IV used 7/16" rod which is .6# heavier and they are the same size aileron. elevators can have extra weight added to the inboard balance arm. you can also move the weight forward on the arm making it longer with the same weight.

 

I mean - 75 cents for a 2.5" grade 8 bolt? Come on.

not sure what that is suppose to mean relative to these aircraft. we don't use grade 8 bolts in aircraft. if you mean aircraft bolts in the ACS or Wicks catalog are expensive, its because of the specs that these bolts are made to. much higher standards then the common grade 8 bolt. as for all the materials used in these aircraft you may find a substitute that seems suitable at first glance but if it is not you may not get a second glance. finding the plans spec materials at a better price is OK but you should be very careful that it is the same stuff and not just because a salesman said so.

The ripple effect would be pretty bad. I'd have to rework the engine intake, the oil cooler, and who knows what else. The ripple effect is BAD JUJU! I also feel the present plan gives a much cleaner appearance. I would hate to waste the drag created by the Plans NACA,(That's easy, close it off. Did I mention ripple?). Plus, another Cozy driver with DDC (and great cooling #'s) gave me some advice on what was wrong with my work. Hopefully, this attempt will be better.

 

Avg. EGT 425 degrees in cruise. Not out of spec, but I think I can do better with some cleaner work.

We know you meant CHT. keep at Jerry I know you will get it sorted out.

Weight is an issue with all planes, aspecially the canards carrying this heavy lump in the back.

 

An O-320 weighs about 30LB's (13.6kg) more than a O-235

 

Would it be possible to lighten a O-320 to the weight of a O-235. I.e. put it on a 15 kg diet.

 

Aren''t there parts, brackets and other stuff such ass covers that can be produced from light materal such as carbon fiber of titanium.

 

Thanks

Ronny

:D :D

not much that you could change on the engine itself. the parts that are removable only weigh about 5 lbs. total so even if you cut the weight of these in half you will only save 2.5 lbs. you could leave off the starter, alternator and vacuum pump. the best thing is to use the light weight starter, alternator and and no vacuum pump or magnetos and use electronics. you are worrying about the weight in the wrong place. the extra HP of the 320 more then makes up for the extra weight. This has been proven by the many planes that have converted to the 320s and they fly great. so much better it would be foolish to build a long ez any other way. resale value can be up to double. On a varieze it makes a rocket. the other thing that most do not know is that the center of gravity on a 320 is closer to the accessory case then it is in the 235. even though it is heavier the CG moves forward with the 320 installed.

Here is a link to west marine. It shows a couple of different kind of blowers.

http://ecatalog.westmarine.com/full.asp?page=442

The squirrel cage blowers are big bulky and probably heavy. I wonder if the ones they call Yellow tip would work. They seam to be smaller and lighter I could put them in line with the heat exchanger. They say they put out 120 cfm.

On the Cozy I have a duct that runs all the way to the back seat of the plane. I wonder if there is enough room to stick the whole heater assembly similar to waiters 2nd unit behind the seat backs above the gear bow and blow into the stock duct hole that we make per plans??? Anybody else thought about that??? Lots of questions STeve

Nope, been there and tried that. you need about 250 CFM and a squirrel gage puts out more pressure then the axial fans do. you need the pressure to overcome the pressure differential that is in the cockpit. air pressure in the front of the cockpit is higher then the back by 1" wc, so you need to overcome that pressure before you can move any air . heaters mounted in the nose work much better then the ones in the back because they don't have to overcome this pressure and the hot air naturally moves from the front to the back. axial fans put out about 1.5 " wc max. Squirrel cages put out 2.2 to 5" wc.

I have a question for those of you with oil heat in your plane. I am in the process of building mine right now and would like to know what kind of fans you are using. Maybe more inportant than type how many cfm of air do they move. I was thinking of using a square type like they use in computors I just wondered if that would work. They are nice and light and eze to mount but I am not sure if they will blow enough nice hot air to keep my toes warm. STeve building on

the Jabsco marine blowers work the best the computer fans do not put out enough pressure to over come the ducting loses.

http://www.westmarine.com/webapp/wcs/stores/servlet/producte/10001/-1/10001/25694?&cid=chanintel&ci_src=14110944&ci_sku=25694

Foam Depot. Thats funny.

 

FiberglassSupply.com carries some Divinycell - I don't think they carry 3lb but maybe 5lb. However, the 5lb is alot stronger and the weight penalty vs the 3lb is like 8lbs in a fuse. Maybe a little more with the strakes included.

 

They carry one type of the Hexcell glass too...I think its the 7781.

I read in Hexcell's product literature that they came up with a new process which improved the strength properties of their 6781 S-2 glass so much that they started using this same process on their 7781 E-glass and improved the 7781 substantially.

 

I'm going to call these guys and see if they sell more than what they list on their site.

 

Re: Berkut wing plans - where can I get the info needed to do the glasswork properly. Also - its my understanding that Berkut wings are the same dimensions as Long-EZ wings and are interchangeble, no?

the wings are the same dimension except the for the trailing edge. the berkut has a straight trailing edge and the long ez cowling will not fit.

OK guys - I'm going to display my (vast) ignorance here. I presume the 703 tape is used to replace the UNI tape for the spar lay-ups. Since this tape is only .010, are you just replacing the lay-ups as called out, or are you filling the area by increasing plies for the final thickness?

this tape is used in the Berkut only and should not be used on any of the other types of canards. it is not a direct substitute if you are building to the plans.

Has anybody tried using pneumatic cylinders to actuate the front retractable gear and the speed brake? Intuitively is seems that it could be lighter because you could have a single motor that drives both. Anyway, I was just wondering if anybody has experimented with this.

the electric has many more advantages than Hydraulic or pneumatic. first it is the same weight as a pump. the gear can be used to raise and lower the nose with the pilot in the seat. the current E racer hydraulic nose gear can not lift the nose so it would require a redesign and a much bigger cylinder. the electric has a built in over center in that the ball screw will only move when you run the motor. hydraulic cylinder would be as big and weigh the same as the electric unit. the pneumatic would be even bigger and heavier. hydraulic and pneumatic requires complicated controls and valves plus it needs a back up method to keep it in overcenter if the main system fails. the electric requires you to install just one switch

Good point, answers in order are unknown,unknown,unknown,and no.

how can there be that many unknowns? did it just fall from the sky and land on your lawn?

Hey guys, I just attended an EAA meeting last night and learned a bit more about my plane, a topic came up that I had not thought much about untill now. My plane does not have a data plate and the history is unknown, It is rebuildable based on the opinion of some fellow canard builders, but how do I register an airplane that I have no info on.

first, was it ever registered? did it ever fly. if so is it still registered? does it have N numbers. if not then it is still a project until it is finished so it can be registered to who ever finishes it and registers it. you are suppose to build 51 % of it yourself but it does not say how many helper you can have and what and when those helpers helped you.