flyingagin

For tacking down the corners and edges of the fabric how does Titebond thinned with water sound? I can apply it with an acid brush and work it into the wood. Dope just ain't going to get as I have fairly bad asthma, and react badly to chemicals.

Oberst

That I can't answer. If no one answers you here, I'd PM a few Moderators that might know the answer to your question. Your build is looking good so far my friend. Keep up the good work!



Pete

flyingagin

Thanks Oberst. Do you have a current build going?
I did not get much done last week. So many things seemed to eat my building time. Did a lot of research and just thinking about options. Also visualizing steps and the exact sequence I need to do things in.
The wife and I spent several hours measuring for the different pieces of material to do the wing, fuse and tail feathers plus all the control surfaces, fuel tank hatch. Trying to figure out the exact sequence to cover the wing (to have minimum seams showing or at least be hid) made our heads hurt. Can't say the fuse was much easier. But now I have a exact plan.
So set up the card table to cut fabric on. I am basically going to make a covering kit.
I guess I will go Thur much of the same process with the fiber glass for the cowl.
I use a rotary knife to cut cloth with (both fabric and glass).
I spray hairspray on the material were I intend to cut. I also use 2 pieces of paper on about a 1/4" either side of my cut line. This keeps the material from fraying , but the downside is it also makes it a little stiff, thus the narrow strip of hairspray.
I think I will use water thinned Titebond to tack the fabric down, Then take the card table outside to the porch area when there is some breeze or light wind and use nitrate dope to seal every thing down. That keeps smell outside and hopefully will not affect my asthma. Then I can shrink the fabric by misting with hot water, and my covering iron and hot air gun. Then 1 light coat of nitrate dope to further shrink the fabric.
Well at least this is my plan, lets see if it works.

flyingagin

This week was ate up other things. I am working on a card table on the porch, outside. Doping down the fabric, just doing all the little details and cut ins right now. slight breeze out there so my asthma is not bothered by the nitrate dope.
This is very tedious work.

flyingagin

Again this week Other things have ate my build time (much better things than last week), but I am try to get done what I can. For the near term I fully expect my time to be taken up, but that actually is a good thing.
Continuing to cover, concentrating on the wing. The tips are a PITA.
Starting to get ready to fiber glass the cowl mold. I realized after the mold was don that I should have put a piece of ply on the back of it were the screws hold it to the fire wall. I had just ran sheet rock screws through the motor mount bolt holes into the foam. Way to soft for that. You really need very solid anchor points. Insert some ply were the screws go. So I put a fat lag screw through the big (1") hole for the fuel plumbing into the foam. That's got her down tight.
The fit between the mold and fuse could have been better so I filled the joint with light spackling and sanded for a perfect match.
Next step, I ran a piece of fabric about 2 inches wide around the fuse exactly at the fire wall mold junction. I did not want to chance that the glass cowl was a tad smaller than the fuse and the fuse is going to be fabric covered. That piece of fabric is not doped down or attached in any way.
After the fabric I have ran a 2" strip of packing tape. This is just plain scotch tape. It will be waxed so I have some chance of parting the glass cowl from the fuse.


Unable to upload pics at this time

flyingagin

I have not been able to upload pics. Will as soon as RCU lets me.
I worked on the glass cowl doing as I last posted. The fiber glass I am using is 4.25 ounce Four Harness Satin (Crowfoot).
http://www.fiberglasswarehouse.com/weave2.php see 3rd paragraph
Very pliable and follows curves great. From my understanding of the thread configuration it should provide a great deal of torsional rigidity. not really necacary for a cowl but great for a wing. I originally bought it for vacuum bagging foam/glass glider wings.
I cut multiple pieces of cloth and laid the on the mold smoothing and stretching as I went. I used a mist coat of Scotch Super 77 contact spray adhesive to hold the glass fabric to the foam and for the successive layers of fabric. Lay the cloth down in swatches that are not to big to manage and add more in over lapping patterns. I made sure to get each and every on as smooth and even as possible before adding next fabric swatch.
After I had put on three layers of cloth (a little more in areas because of overlapping) I started applying the finishing resin, using an acid brush to spread it on. I also tried to work the resin in by additionally brushing what was already there and pushing (stabbing motion? poking?). I also used a plastic spreader to help work the resin in.
The fabric became more translucent as I worked the resin.
Still there are some areas were it is not as translucent and I wonder if maybe I did not get those areas whetted out sufficiently?
I had my wife take pics while I was doing the glass work so as to demonstrate how I did this job.

Man O Man I sure hope I can get the cowl off the fuse when it is dry.[sm=drowning.gif] I will cut a parting line about 3/4 inch behind the fire wall.

flyingagin

OH NUTS.[X(] The screws and lag screw that hold the mold to the fuse now really buried in the fuse. I installed them with the fuel tank hatch off and then fastened it on (two dowel pins in front and a recessed bolt in back under the wing). Well with the cowl glassed and overlaping the hatch I cant release the hatch[sm=drowning.gif][sm=angry_smile.gif].

flyingagin

I marked and cut my parting line for the cowl carefully cutting just through the glass. Removed the waste end (back).I can get my hand down inside the nose and feel the screws, but can't turn them with my fingers. Gotta get the lag screw out, use a socket. Don't know what size it is.
Wife said 9/16. Tried that and it is 9/16s. Boy is she smart.

flyingagin

Got the screws out using a socket, ratchet and long extension. Along screw driver did it for the smaller sheet rock screws.
What a relieve.
I had two layers of covering fabric (polyester dress lining) wrapped around the front from the fire wall back about 3". Grapped a corner of 1 layer and started tugging,. Took a lot of force but it started to slide, so I just kept working my way around and around till I had it all out. Then I did the same thing with the scotch tape. Only some of it came out. I gave the cowl a couple of open handed slaps (gentle) around it, then grapped it and pulled. WOW it just popped off. WAY COOL
Parted the tank hatch and removed the rest of the tape.
I HAVE A COWL
It slides on nice and easy.

flyingagin

I used a soldering iron to dig out the foam. Also a wide flat blade screw driver to scrape it off the glass

flyingagin

The circle will be cut out for the cylinder. I still have all my openings to cut out. That will be done just about last. I need to sand the outside, remove defects, and apply several coats of thinned resin to get this cowl real smooth.
Also I need to clean the inside a little better.
I will mount the cowl to the fuse with some real small button head Allen screws

Oberst

Yes, but I'm not doing another build thread right now. Kind of need a break from doing the Fokker Dr1. Right now I'm redoing and customizing a very early League Models Neptune Seaplane. I'm modifying it to have a seperate flap function and its going to have retracts. If it all works out it will be a true amphibian. Last Spring I had a "Deadstick" too many and pancaked it in the water when I tried landing down wind. I busted up the wing pretty good, and broke the main spar in half.

I've been posting a few pics, but I've been keeping most of the build under wraps because this is experimental. I'm not sure if it will work, even though I think I can make it work if you know what I mean.

The first few pictures is this plane I'm rebuilding before the crash. The later photo's is what It looks like now. I'm making it a " What If " Luftwaffe 46.


http://www.rcgroups.com/forums/showthread.php?t=1413244


It's good to watch how you did the fiberglass cowl. I heard about how you make it, but to see the pictures on how it's done makes a big difference. Fantastic job! And thank you!



Pete

flyingagin

Hey thanks Osbert
Made some mistakes that I will not make next time.
#1 Got to thin the resin out good so it really penetrates and wets out the fabric. I will be doing some experiments on some throw away dummy parts.
#2 See #1

Not yet satisfied with the inside of the cowl much less with outside. It aint got to be perfect but I sure don't mind if it at least looks like it is. Will strive for that.

Down the road for this bird are wheel pants and FLOATS. When I first acquired this plane I had a kit for wooded floats given to me. I thought they were a bit heavy and the extra fiber glass landing gear strut only compounded that. But the plane just did not seem to notice although I made sure to keep it a little hotter than normal on landing. I had added a sub fin to the bottom and that kept it well behaved in yaw. I had a total blast flying off of water. Now the vertical stabilizer area is significantly greater and taller, so I hope that is all it will take.
I will look and see if they are suitable wheel pants (for not much $), or I will just build some. I have been brain storming them already.
Floats and struts I am definitely going to craft myself. Aluminum struts. And fiber glassed foam floats.
Still a lot to do on this plane.

flyingagin

I used some thinner on a acid brush to finish cleaning out the inside of the cowl. It got the job done but fast an easy.
I can definitely see places were I did not get proper wet out of the fiber glass fabric with resin.
and once again the site is having technical problems, can't post pics.
I intend to put 1 layer of glass on the inside of the cowl starting from the fire wall line forward. I WILL USE THINNED RESIN LIBERALLY. That I hope will get the areas that did not get whetted out right the first time. Then I will seal the inside with non thinned resin to avoid any oil soaking or penetrating.

MetallicaJunkie

looks sweet flying again.... the reason i ask is because i have a plane that needs a cowl, the red plane in the pic......and i will eventually use your thread as a guide.....

flyingagin

I had intended to add 1 more layer of cloth to to the inside of the cowl. But I just don't see that it is needed. The cowl is plenty strong as is. And just coating with thinned resin wet out the areas that did not get properly whetted out the first time.
I have opened up the nose ply ring and chamfered it.
more pics to post but not till the site is working correct. seeing references all over the site about that.

flyingagin

Hey MetallicaJunkie go for it. Good looking bird will only look better with a cowl. I have found it is not that difficult, but is time consuming.
I will post an addendum on experiences on making a glass cowl a little later. Sort of a lessons learned, adding a " kind of should have done " to it.
Next cowl (oh yeah there will be more) will use a balloon over the lay up, should produce a much better outer finish.

MetallicaJunkie

do you think glazing putty would work for smoothing the finish? i have a couple of ubes

flyingagin

The way I see it the smoother you make the mold the smoother you make the INSIDE OF THE COWL. That's all fine and dandy but it is the outside that is of interest. I have not tried it yet but a balloon over the wet lay up should give a nice smooth even finish with no fabric swath lines, as well as squeezing out excess resin (wight). Inflate the balloon and the wax it or use silicon spray mold release. Heck you could even use some LARD, yes lard for cooking. Smear a thin , but not to thin ( about like what you would use for baking a cake or brownies in a glass pan ). The lard has no efect on the resin curing and smooths out under pressure. And it will release fantastic. I have actually used it
When you inflate the balloon ( get 1 that is pretty good size ) lard it up or wax it (Carnuba works good several waxings needed and barely wipe off the last coat) or spray with silicon mold release. As you press the balloon over the lay up let the air out as you go. balloon should just pop right off when the resin is dry.
I quess this would be sort of a poor mans vacuum bag. I have done that for glider wings, but they are not all compound curves. But the balloon will do compound curves nicely.
still can't post pics

flyingagin

By the way here are a couple of pictures of my last rebuild. I crashed my son's airplane, a scratch built form plans Kadet JR. O.S. .25 for power. Tried to force it off of grass and did not have the needed airspeed. Tipped stalled violently and DESTROYED the fuse. The wing and tail feather suffered nothing more than getting dirt and grass on them. So I made a new fuse and wooden cowl. Kept the original paint scheme. I finished that rebuild this past January and then started this current project.

Darn, I do not have any pics of him with the airplane.

Nuts still can't post pics

flyingagin

I applied a butter coat of resin to the cowl inside and out last night. That sealed and filled the last of the cowl except for 1 little patch that I must have missed. I sure miss having good lighting to work by.

I started sanding with a sanding block that has a foam pad on it I think I have either 180 sandpaper on the block. coarser would cut faster, but leave deeper scratches and maybe cut some glass threads. Patience and elbow grease is the order of the day here. Thankfully it sands pretty quick. It is very easy to see were more sanding is needed as those spots remain shining. I do have some small bumps to sand down and some places were the top layer of glass has a bubble in it. The fabric lifted above the underlying layer of cloth forming a bubble, may also have entrapped an air pocket when I applied the resin. Again using a balloon would have eliminated this problem and I would have a lot less sanding to do. I also think the cowl would ultimately weigh less. SO it is sand. sand, sand and more sanding. It is leveling out fairly quick. I am taking it almost down to the glass. A few spots are low but very small, so I will smear some thinned out resin on with my finger.

Will post pics when the site is working for that again.

flyingagin

Sanded the cowl down after applieing a second coat of resin. Man what a lot of sanding. Found a small area by the nose ring where the outside layer of glass was not bonded to the underlying layer. I tried to slit it and bond to theunderlying layer. At the same time I put a coat of really thinned out resin on the cowl. After it had dried the next day I found my attemp to bond the 2 laers did not work. OK fine, I cut the piece of glass off and mixed some resin and micro balloons (a lot of micro balloons) and a puttied it. This morning I saned it down to match. Looks fine and feels fine, will never see it after the sandable primer is on it. I am debating wether or not to use this cowl as a plug and make a mold from it or not. If I cut wrong or later dork the nose rather hard I could quickly make a second cowl.
At any rate I want to learn how, as that is how I intend to make my wheel pants.

flyingagin

I have restarted covering. I have gevin up on useing Nitrate Dope to glue the fabric down. I am now useing MINWAX water based Polycrylic. This is working very well. Cleans up in seconds with water. ZERO SMELL. I use a foam brush to paint the corners and an edge. Once dry I use my covering iron to iron the fabric down. The fabric sticks just like it had glue on the down side. This is easy and since I can do it in the house fast. You have to use razor blades to cut the fabric. An exacto just ain't sharp enough. Wintips, center wing and top of fuse covered.

Oberst

It's getting there!!!!


Bad news, I had a heavy shelf fall on the Neptune Amphibian. The plane is totally destroyed. I'm not going to even attempt to try to fix it. It's beyond repair and I've spent enough cash and time on it already. Plus they still make the original Neptune and I can always get another one for $100. Bumber!



Pete

flyingagin

Wow now that is areal bummer. the closest I have come to that kinda of thing is My younger son when he was a todler sat my 1929 Great Lakes 2T-1A trainer. Minor damage as I grabbed him and picked off in time. He still remembers that he broke it. I just remind it was not bad.
Oh I did catch a foam glass wing in a garrage door once. Garbage can stuffer.