jroth

My Feedback: (60)

I spent Saturday driving to the closest F-9F-2 that I could find, it has been repainted several times with what looks like latex house paint, but all I was looking for was structure detail. I took over 250 photos.
Here are some pictures:

jofunk

Mr. Fun came over yesterday to work on the oven for the canopy making process. It is a little hokey looking being made or warming trays. but as John said it only needs to reflect and focus the heat on the material. I know he didn't want to make a 24"x36" commercial heating element that he would then have to store somewhere. I hung everything I had finished on my plane and took a few pix. everything is there except the top of the rudder and a canopy.

smokinwoody

nice job guys....what are you going to use for engines..

jofunk

John...... you spent all day Saturday driving to take pictures of a f9f-5 and not a -2. But that's ok most of the lines will be in the same place. Ziroli has a mish mosh of 2 and 5 details on his plans. I saw a good pic. of a 2 exhaust I'll see if I can find it again and put it up here.

jofunk

here it is.

jofunk

maybe

owl182

One of my goals was to try to fabricate as much of my project as I could. When it came time to form a canopy I began accumulating various components in the hope of pulling my own. Vladimir and Hal had already put substantial time in completing the plug- my small contribution being the application and buildup of Bondo. Hal did an excellent job shaping and finish sanding the plug as it is quite smooth with nice symmetry. One of the first things you need is a frame into which you can mount a sheet of PetG plastic. This will be heated in an oven until it literally sags under its own weight. Here's the frame which I constructed from select pine boards from Menard's .

owl182

Then you need an oven to heat the plastic mounted onto the frame. The plastic is stapled every inch around the perimeter of the frame . Since my kitchen oven was too small I had to construct something which could heat a 36" sheet of PetG plastic. I'd seen an interesting and inexpensive home made oven with 2 electric hot plates on a vacuum forming site. Their oven used stacked aluminum throw away grilling pans. My only problem was that they were only 16" long and I needed 36"! I do some work at a bowling center which has a banquet hall attached to it. Fortunately for me I kept a keen eye on their dumpster and what do you know-a bunch of free aluminum pans(I did have to wash the sauce and beef and chicken residue from them before use but no big deal as they were FREE). Must have had a big banquet.

I then went about cutting and splicing them together using scissors and sheet metal screws. That took a bit of time as it is a rather delicate device and flimsy, and it needed to be fit to the frame I'd made. For heat I shopped the Goodwill stores, coming up with a large electric dual bar hot plate for $8. Another small single one for $4 and one single burner which I had already in my possession. During the heating process I had to run the chords to different rooms as I didn't want to blow all the circuit breakers when everything lit up. I'm doing this in my dining room (no basement).

Here's a photo of the oven:
It is 3 levels high, and I used 12 aluminum pans to achieve the required length and width. It gets hot quickly and the .040" PetG sags 3-4" in 4 minutes. I don't use a lid on it because the plastic began sagging really quickly-too quick for my reflexes. Total cost for materials was around $20. I had to buy some grill toppers (aluminum single use flat pans with holes in them) to cover the burner coils and redistribute the infrared heat out to the edges, eliminating any large hot spots in the plastic. It seems to work.

owl182

The next thing I had to do was to build the vacuum platen. I utilized a synthetic bowling lane panel I had on hand-it is very rigid and smooth. I bored a hole in it and attached some plumbing pipe along with a one way sump pump valve ($7). I then attach a shop vac to the end of the line. I was planning on adding an additional high vacuum source to the valve but it seems it is not needed. There are a couple of frame guides attached to the board, which aid in alignment during the mad dash to press the hot plastic on the plug. You can also see the black foam weatherstripping ,which the hot plastic and frame is pressed against to make an airtight seal. I've also carved a riser block (pine wood) to raise the plug higher during molding-I couldn't get a sharp edge without it. Popsickle sticks are CA'd onto the riser both top and bottom, as we need to channel suction around the perimeter of the plug.

The first image shows the board top with riser and weatherstripping and guides. The oven sits next to it.
The second image shows the plug with plastic on it as well as the plumbing running under the board. The entire vacuum board is mounted onto a workmate.

owl182

Here's a view with the plug on the riser with a pulled canopy still in it's frame.

owl182

I had initially attempted to work alone one night. My first canopy was 95% good but I couldn't achieve a quick enough seal (the frame is 36") so the plastic didn't get pulled at the edge near the tallest area on the plug. I'd also used too few staples and the plastic pulled slightly from the frame-also losing vacuum. I also initially shimmed the plug with nickels BUT 3 of them got sucked into the plumbing and I lost more suction. I also experimented with directly heating the plastic without the grill topper aluminum inside the oven AND I put 3 cookie pans as lids on during heating. The plastic began to sag so rapidly I had a 7" sag before I could remove 3 hot lids and the plastic folded over on itself in a few places during the pull so the part was of no use. 2 down but not giving up I called Joe and asked that he come over to help out. I needed another pair of hands to help get the frame pressed against the seal more quickly. He also brought his larger shop vac along- I was hoping it would help with making a useful part. Dennis also wanted to see the process so Dennis and Joe had dinner at my home while we discussed the plan of action. I ran a couple of you tube videos on vacuum forming so they understood what we'd be doing.

So the process began:
I stapled the plastic to the frame while the oven heated up. We then placed the frame and plastic on the oven top and watched it carefully. It wrinkled a bit then tightened and slowly began to sag. I flipped it over once to heat the other side of the plastic but I'm not sure if it helped. Once the plastic drooped about 3-4" (taking about 4 minutes) I told Joe to turn on the vacuum. I quickly lifted the frame from the oven top and in one motion turned and pressed it down on the plug. Joe and Dennis quickly pressed the areas of the frame I wasn't able to grasp and we achieved a seal quickly. The plastic pulled tight and we had a useful canopy We let the vac run a couple of minutes while the plastic cooled. It came off of the plug with little resistance.

Here's a couple of photos of Men At Work: You can see Joe and Dennis inspecting the pull in the first image. I'm in the second image, just happy that we were able to make a couple of canopies

I have some minor imperfections to deal with, notably tiny specks of something getting into the plastic, almost looks like dust particles or something. I have a video of someone using an anti-static plastic cleaner spray. Perhaps this is something necessary which helps prevent this problem. Overall I'm satisfied that I can make the canopy without outsourcing -it's a pride thing. I'll be able to say I made the canopy along with the rest of the jet- after all that's what scratch building is all about. Thanks again to Vladimir and Hal for the plug work and Dennis and Joe for their muscles. This definitely requires a group effort. I'm going to experiment a bit with the plastic and see if I can refine the process to make some really good canopies for our use.

At least I didn't burn the house down!
Sincerely,
Mr Fun

owl182

Uh Ohhh! Drat!

owl182

Ok I had my fun with the last image. John Roth and Dennis came over and helped me pull some more canopies. This time we cleaned our vacuum cleaner inside and out and left the filter in it. We also used some compressed air to blow the plug down just before we pulled the canopy. I think dust was settling down onto the plug while we waited for the plastic to melt. It could have been that last night we circulated dust by not having the filter inside. As we pulled vacuum the exit on the shop vac was distributing the dust all over the room-I think. I never saw particles floating in front of me but they were evident in the canopy. I thought we'd lose some vacuum with it in(duh mistake). I bought some more PetG plastic, this time a sheet of .060". I was curious to see if this thickness could be formed using only a shop vac as a vacuum source on my same setup, but achieve a little stiffer part. It turns out if you wait 5-6 minutes and get a really nice droop in the plastic you can achieve some really nice results working at home. Using a soft cloth (no scratchy paper towels) and glass cleaner along with the compressed air we pulled 3 really nice ones. The little peck marks were nowhere to be found so they were indeed contaminants from the surroundings causing the problem. The home built oven handled the heavier plastic with ease. Again Dennis and this evening John R helped with the prep of the plastic and muscle to get a quick seal against the platen. You can tell by the smiling faces that we were successful.

vholis

On the Panther #4, rudder and elevator is attached and secured to the fuselage. - Vladimir Holis

vholis

Club meeting in February, all four Panthers was together in several stages of construction.

cmjets

Hi:

Vey cool 4 1/4 Panthers, look great.

Best Regards from Spain.



Carlos Márquez.
_____________________________________
http://cmjets.blogspot.com/
http://picasaweb.google.com/cmjets2007

jofunk

Since flying season sorta started here in Chicago and our club had its first combat event the building parties may need to switch from Panthers to combat planes so Mr Fun can finish a gremlin........... I need to finish my vertical fairing above the exhaust and the rudder hinge cover so I can start laying some glass on the fuse. I took one of the not so good canopies we made to see how it fit on the fuse. It looks o.k. with just a few areas that need to be built up to meet the canopy. Once that is done that area can get hardened with some fiber glass and the hatch cut away. When I get the top all glassed then I will flip it over to glass the bottom.

Falcon29

My Feedback: (7)

Panther #4 showed up at my house today ! After barely getting it to fit down the stairs into the workshop here are a few pics of how huge this thing is compared to my Jetlegend F-4.
Even the Panther's JetCat P-180 looks tiny next to the fuselage. I'm going to start the glassing process here shortly while Vladimir works on the wings.
Needed to ask what oz cloth would be ideal for a plane of this size ? would 2 oz on the fuse be too much ?




Roman

Boomerang1

And the next project?

http://www.airplane-pictures.net/image14632.html

Good luck with your cats! - John.

jofunk

I Started glassing my fuse, stab,tip tanks, and control surfaces. It's a lot of area to glass. The front of the fuse hatch and the tops of the inlets took 4 pieces 14"x50". I then doubled up the line where the hatch will be cut out............ Roman you asked if 2 oz. is too much. Yes if you are just looking for a surface to finish. No if you are looking to add some strength. We blew these plans up from a 72" version with 1/8" lite ply bulkheads and 1/8th balsa sheeting. These 116" versions still have 1/8" lite ply bulkheads and 1/8"balsa sheeting. I'm going for adding a little strength. The stuff I am using is 2.6oz. and will be doubled in some areas. I've also used this weight cloth on some other normal sizes Ziroli war birds doubling and tripling it up in spar and retract areas and didn't have a weight issue. The planes balanced easily and seem to fly pretty good.

jofunk

Some pix. maybe.

jofunk

I was Mr. hatch blower yesterday. For friends of the The Right Stuff. no Mr. president, no Jackie, no parade.........IT WAS A GLITCH!!!!!!!!!!!!! Anyways here are some Pix. The next step I'll harden the area with some glass and resin.

smokinwoody

Joe...this is Jeff...the guy that worked for willow..

and use to be in the club...

anyways..very nice projects...what are you using for power

also..like I stated in another posting...if you guys like the Panther so well...why not use one of them as a plug and make a mold for fiberglass/carbon fiber planes...the entire thing..fuse, wings and tail feathers...you can then make at least 5 of them and sell them to finance the projects...bet the bird can be built at 40lbs all up and use one of those P200's or a P180 depending on the wet weight...

love the project guys..I'll be at the flying field to see the first flights..

Jeff

jroth

My Feedback: (60)

Mr. Fun, Joe and Dennis came over last night to do a little work.

We cut the Ailerons and Flaps out last week and we center hinged the Ailerons last night, the full scale had piano hinges on the top of the wing, we chose to center hinge like the elevator hinges that we made.

The Flaps will be next, they will be bottom hinged and then we will make the servo pockets in the wings.

Falcon29

My Feedback: (7)

Started the glassing process, thank youJoe for the advice. I think I used close to 5 yards of cloth for the entire fuse top and bottom !






Roman