airbatik

Hello everyone,

I have been out of the hobby for a few years. Just got back into it and decided before spending money on AMA and fuel i would make a Fast Little Parkflyer.

So here goes nothing, I started last night after printing plans i worked on a few months ago. The plans were originally for a larger electric made from balsa, but i found this depron and couldn't resist. I have built a few scratch balsa planes but this will be my first built up depron plane.

I will be back with more information but it will be 34in wingspan, 193 sq/in, 350 sized motor. Should be fast and small.

Thanks
Alex




Alex Reigle NO AMA Flagstaff

CastorTroy2150

My Feedback: (10)

2 things...
Looks GREAT! Its nice to see someone building something other than a profile plane from Depron. Second, what plans are you using, or did you design them in CAD yourself? Tell me you aren't freehand/braining this, otherwise I will hang up my building tools and quit right now, feeling that inferior, haha Will be following closely on this one, so hurry up!

airbatik

I am building from plans i nearly finished a few months ago. I am about to get started again so i should have some more pictures this evening. Thanks for watching!

Alex Reigle No AMA

FlyDave

Interesting build ! i'm curious to see how it becomes when finished.

Did you've already choosen the final colors ?

Greetings !
Dave

Tsavah

Dang, still no pictures or response to the last post. Waiting with baited breath to see if this is a Hellcat, or another model. Looks like something Iwould want to do.

airbatik

Sorry guys, school hit me hard last week. Got some new pictures to show though. It's coming together some. The nose seems too wavy for me so i'm hoping some light weight filler will fix it. I'm uploading pictures now.

So far the fuse weighs 2.5oz's so i think the 26-28oz final weight is very doable.


Alex Reigle No AMA

airbatik

Here are some pictures. I have a couple paint schemes i am considering. Does anyone have advice on a filler to use? I've never really scratch built something so small. Micro bubbles in the filler right?

airbatik

The retro paint scheme is really cool in my opinion. It is not a hellcat, it's a Pilatus pc-9

Alex Reigle No AMA

BigP38Lightning

Which version will you build?

In the picture you post you have the main versions PC9-A on the side and the PC9-M in the middle.
You can see the triangle added on the rudder on the M version, other little details have changed between the two versions, their was a bump on the right hand side on the A version that has disapeared on the M version, and Karman has been added on the M version also.

FlyDave

In USA you have many choices, try to find on your hobby stores this product or any similar, it's very good for foam or depron !!

DAP® Fast 'n Final® Lightweight Spackling

[link]http://www.dap.com/product_details.aspx?product_id=61[/link]

Or any other lightweight spackle work fine.

airbatik

BigP38Lightning. Those pictures are just for paint scheme ideas.

Thanks Dave, With some heavy sanding it actually flattened out nicely. I will still need a touch of filler but this foam is amazing. Has anyone seen a real stellar paint job on depron around RCuniverse? I'm curious as my airbrush is long gone and i am planning on using water based spray cans. Maybe i will need an airbrush though.

Thanks Everyone for watching.
Alex

airbatik

Well the fuse is nearly done. I guess it's time to start cutting pieces. The "hobby Shop" in this city let me down for the last time today. It is hands down the worst hobby shop i have ever seen. Unless you want to spend your pay check on some 1/19 scale rc car then there is nothing there, including foam-safe CA glue. The airplanes on the ceiling are not for sale.. I will get all the pieces cut and ready to go so after i go to the city i can start again.

I am still looking for a filler that will work. Can someone tell me about the micro bubbles?

Thanks all,
Alex

Alex Reigle No AMA

Tsavah

Ihaven't used a product like micro-bubbles for a very long time. I think the same thing is called micro speres and other names for round objects. What I have used is talc powder that comes under many names, but normally mixes in well with just about anything. I normally mix a bit of talc with expoxy or water based, or water thin-able products Iuse as fillers or a primer. Not sure of your planned use for the micro-bubbles, which could be tiny glass beads, so I cannot say if talc will work just as well for you and save a lot of money over the years. Talc is sold as baby powder and other body soothing products with or without prefume.

airbatik

Well after sanding there are a couple places that need risen. There are not many spots but i would like a rock solid base to prime sand and paint. The goal would be a paint job without the classic apperance of painted foam. So a primer and filler are my basic needs. I have heard the micro bubbles make the filler lighter and i may try the baby powder idea on a test piece.

airbatik

As you can see in the second picture, I need a small bit of filler to sand down so it will look right.

I need a flexible filler and a water based primer. Help me out folks!

Tsavah

A water thin-able primer and filler is a good way to go, as long as the weight gain is minimal and tuff enough to handle the flex of the foam. A while back I came across a mixture for foam aircraft projectsyou might want to experiment with. The basic ingredient is Lite Weight spackling compound available in all sorts of stores where wall board, plaster board and other like supplies are sold. I bought my last tub in Wally World (another name for Wal-mart) and the stuff is so light you swear there is nothing in the plastic tub, even the larger quart size. It is also water thin-able and water clean up as long as you do so before the stuff cures. Read the warning label so you know the risks and don't add much water to the paste or it might dry with cracks or unacceptable weakness. What you can do is thin it a bit, or a bunch with other water thin-able and clean up products that won't harm foam either. It is always best to test any product you think will work, and after curing over night, stress test the sample. Give it any sort of test you think will prove the stuff will stay put, not crack under stress, or chip off in the future. Any other test criteria is valid if it can prove your product mixture needs improvement to preserve your work.

One of the products Ihave used to thin the spackling compound to make it more flexible and easy to paint on in very thin layers is called Polycrylic (water-based) produced by Minwax. It is a protective finish, durable and fast-drying, which makes it very compatible with the spackling compound characteristics. So far Ihaven't found a foam it will harm, and it protects the foam from all sorts of paints or primers that will damage various types of foam either a little, or more so. Of course you have to take care not to sand the protective coating away, or all bets are off if you later apply a paint or filler that will damage the foam. As with any productread the warning label and wonder if mixing the spackling compound with the Polycrylic might produce an unknown hazard. I don't know of any problems and have had a great deal of success with the two products complimenting each other in a variety of recipes and applications on foams from more than a few makers or sources. As one would guess, you don't want to use any more of the product or of a mixture (recipe) than is needed and you want to apply in thin coats if more than one coat is necessary.

When ever more than one coat of anything is applied, the general rule is to lightly sand in a gentle matter between coats, but only enough to remove any hint of wax or a shine on the surface of the prior coat. The idea being not to remove a noticeable amount of the prior coat, but enough to allow the next to "bite" in. In one of my recipes I added a bit of talc powder to stiffen the mixture and applied it a tiny bit thicker than Inormally would. One foam I haven't played with much is EPP board, which is very damage resistant and a target foam for future experiments and model RC airplane projects. I may find it necessary to use very little spackling compound or talc in future recipes with the EPP foam. Imay even discover Polycrylic won't stick to EPP because of the foams ability to be crushed (withinlimits)without a noticeable damage mark after a short rest period. The damage resistance of EPP foam makes it a wonder product for RC flyers, but it also can be too flexible to hold the desired shape needed to be air worthy without stiffening materials like carbon fiber rod, tube, sheet, or flat stock. So finding a good recipe for priming and spackling EPP can be a challenge, but it can also provide a "skin" for EPP that might make it more air worthy with less need for carbon fiber parts or a fiber glass and epoxy skin.

Maybe someone else has already come up with a solution for EPP foam, but I have no knowledge of another thread about this as of yet. There are many places a person might find the opinions and notes of others experimenting with EPP foam primers, fillers and coatings and Imay never come across them. There is little to no reason someone with this knowledge would look for others seeking the information in a thread subject of; "Scratch Build Thread, PC9 Parkflyer", but they might investigate and comment in a thread with a more on topic subject heading. Think about that when you have a specific question others might seek answers for or find interest. It may be time to think of a very narrow subject and start a new thread. Maybe if we can think of a better way to word the subject heading we might stir up some information from others already gone down the road and are willing to talk about it. I will also give this some thought and try to come up with a subject heading for a new thread that is better than; Primer and filler for EPP (or another)foam. If not, Iwill use or you can use it for a new thread, but it may be better to follow the subject with a question mark as a good way to capture the interest of someone with an answer or two.

airbatik

Thank you Tsavah. As to making a new thread it seams to me that you have answered my question in enough detail for me to start experimenting. Alas I have run out of glue and so until next week i will have to stick to cutting foam. It is actually for the better as i am preparing to take my Private Pilot exam and should be studying instead of building. Next week will bring new pictures and hopefully a flying model.

Alex

Tsavah

Best of luck on the exam and I will be looking forward to continued progress on the RC plane after you are certified as a pilot, or a tad sooner if you have the spare time. I do hope your dream of becoming a pilot in the 1:1 scale planes works out better than expected.

airbatik

I was doing a little research last night on forming lexan. I have always wanted to try it and this time i think i will. The Canopy will look much better if it is made that way. I will have access to a shop vac this weekend so i think i'll give it a go.

About EPP foam, it is very interesting. It would seem best to use it in conjunction with another type of foam, much like the ZAGI uses it for the Leading Edge of the wing. I wish i had access to it because i think that is the best application for it and i will have to try it in the future.

Tsavah

EPP foam is sold by a number of foam plane makers and suppliers of RC materials (new or independent small operations) in sheets for scratch builders. You can look up a few in here and other RC group sites by searching on EPP, or foam. Ithink I read at least one of the web site owners that sells EPP foam sheetsis a member of this group and has left his .com addy with a statement he sells the foam board. You can also find the foam used to ship furniture to stores and I am told dumpster diving can yield a significant find during holiday sales and other days. I bought an EPP foam kit from Budget RC to build the "Nutball" parkflyer and am in the process of attaching the electronics and motor. The foam is very spongy and can be twisted within limits without noticeable damage, but some glues don't hold onto it very well. The other primary reason few use it is a lack of stiffness under load. You have to remember it likes to flex and place stiffening reinforcement and carbon fiber rod, tube, or flat stock are the most common ways.

The Nutball has carbon fiber flat stock in the front, rear and in the tail/rudder and the stripsare around 3mm by 1mm. It isn't much in the way of stiffener, but it works well enough to make the EPP stiff were it needs to be. A search on the web will yield a few pictures of what the sheet flyer looks like, but there are other sheet, or flat flyers just like it by other names; snowball is another example. They all look like pancakes with a motor, tail and RC electronics glued on. They are what you might call a trainer type of RC fun flyer since you can crash them many times and keep going unless you break a propeller or some other significant part. It isn't likely you will break the foam, but it can be cut or torn by obsticles, even though it is resistant to both types of damage. With the right kind of flexible glue the cut or tear can be repaired quickly andRC pilotflight training can continue as if nothing happened. Hot glue is a common construction and repair glue for EPP foam, but you do need to be as sparing as possible to keep the weight down.

highfly3D

I am thinking thinking making this plane out of a foam block & using hot wire is easy than making it in a built up way.

airbatik

Yeah that may be true but i am really happy with how the fuse turned out. I will have some more pictures soon, school has been killing me and i ran away to Sanfran this weekend, time to dust out the cobwebs and finish this wing. I am getting excited to hope it flies!

wingnutzster

Consider using what i consider to be the best modern scheme on the pilatus, that of the SAAF(South African Airforce) Silver Falcons display team. Whilst it is true that our aircraft are specially built PC-7 'Astra's' - a cross but essentially a PC-9 with some of the simpler systems of the 7 and the lower rated Pratt&Whitney.

Externally it is the PC-9M with the added dorsal fillet on the fin as well as a higher canopy profile and longer spinner and other small details. A beautiful bird we are very proud to fly in the pilot training role before moving on to the frontline fighter trainer -the Hawk 100.

Even prettier than the standard red and white trainer scheme is that of the falcons. They originally wore the same livery as the trainers in the fleet but have a new shiny speciality scheme in which they perform at airshows all over the world.

http://aerobaticteams.net/silver-falcons-gallery.html

wingnutzster

excellent build btw!