HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Mar 17, 2012, 01:08 AM
Addicted to building...
Freddie B's Avatar
Omaha Nebraska
Joined Feb 2006
5,992 Posts
Quote:
Originally Posted by gmwahl View Post
Just cover the plug with brown paper and 50/50 carpenter glue and water, one layer works ok , two is almost overkill, and they hold up for several pulls.
Learned this from Mintie on one of his build logs. I tried it and it is super easy, and quite resilient. You can really sand it well too.

Mike
That is a wonderful way to do it. I usually give a couple layers of fiberglass using 5 minute epoxy because it is fast and easy. The Paper glue is much cheaper I'm sure. I have been playing with using the newsprint, and also tried silkspan with the glue. Newsprint is by far super strong, but more than one layer would be needed to equal brown paper. Thanks again, next time it's paper/glue for me!

Fred
Freddie B is offline Find More Posts by Freddie B
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 17, 2012, 06:42 AM
Now in TN!
J Morgan's Avatar
Chapel Hill, TN USA
Joined Apr 2001
24,337 Posts
The brown paper sounds interesting. May have to try it.
Hersch,
The way I do it is here on page two of my blog:
http://www.rcgroups.com/forums/showt...+canopy+making

I had several requests on canopies so I did a build thread on it. This is pretty well how I still do them. I still use foam, protect with epoxy and then a bondo covering. And you can get the bondo real smooth. Unless you get the plastic too hot these will hold up for several pulls. But eventually they will break down from the heat. But how many canopies of the same plane will you need to pull? So it works for most uses.

J
J Morgan is online now Find More Posts by J Morgan
RCG Plus Member
Latest blog entry: OV-10A Bronco from Palmer Plans
Reply With Quote
Old Mar 17, 2012, 09:32 AM
Now in TN!
J Morgan's Avatar
Chapel Hill, TN USA
Joined Apr 2001
24,337 Posts
If I don't know much about fiberglassing, I know even less about retracts. I've never had a flying field that would support gear unless it was 1/4 scale bush tires.
So I'm leaning heavily on a friend for support on these, much as I did on the A-26K ad the B-24J. Those worked so hopefully these will too.
Problem with the Able Dog is that the gear is so far forward. All the way up by the LE, doesn't leave a lot of room even with this thick wing.
I'm using the FMS Corsair rotating retracts, supposedly good for ~ 10 lbs. Got them from pw-rc along with struts.
Here is the way I'm setting them up. A front plate of 1/8th ply with cutouts that accept tabs from the 1/4" gear plate. Then a 6" long 1/4" rear spar. The slots for the spars are cut through the wing so when it comes time to glue them in I can slide the spars up or down, and angle them sideways to get whatever angle I need for the gear.
I made a channel to glue in a plastic tube for the gear servo wire.
Also made a paper pattern so I can sheet the wing and then remove whatever skin I need to glue in the gear assembly.
That's about it, all I need to do now is decide where I will place the wing servos and cut the channel for them to glue in plastic tube for the servo wires. Then I can sheet the wing.
Planning on single torque tubes for the flaps and a single servo.

J
J Morgan is online now Find More Posts by J Morgan
RCG Plus Member
Latest blog entry: OV-10A Bronco from Palmer Plans
Reply With Quote
Old Mar 17, 2012, 10:02 AM
michigan jet guy
mrshea's Avatar
USA, MI, Caledonia
Joined Jul 2007
1,083 Posts
j i have to ask , what are you using to sand that white foam without it chunking? I've tried sanding it at a certain point it just starts to chunck instead of sand. Phil
mrshea is online now Find More Posts by mrshea
Reply With Quote
Old Mar 17, 2012, 11:20 AM
Now in TN!
J Morgan's Avatar
Chapel Hill, TN USA
Joined Apr 2001
24,337 Posts
Hey Phil,
Correct, it is difficult to sand. Light pressure, sanding blocks with 120 grit and finish with 400 grit. You have to clean the surface all the time to keep particles from building up. They will build up and that's where the chunking occurs.
This is really bad white foam, I think it was made before they got it right. I've found numerous pieces of hard plastic in it that leave a hole when you pull them out. But once sanded and skinned you'll never know it.

J
J Morgan is online now Find More Posts by J Morgan
RCG Plus Member
Latest blog entry: OV-10A Bronco from Palmer Plans
Reply With Quote
Old Mar 17, 2012, 11:34 AM
michigan jet guy
mrshea's Avatar
USA, MI, Caledonia
Joined Jul 2007
1,083 Posts
oh ok i've been using 60 grit to knock it down but haven't been cleaning it off. That would explain it. Thanks Phil
mrshea is online now Find More Posts by mrshea
Reply With Quote
Old Mar 17, 2012, 04:51 PM
Capt. Z
falcon5's Avatar
United States, NV, Las Vegas
Joined Dec 2004
2,568 Posts
Lookin great!
falcon5 is offline Find More Posts by falcon5
Reply With Quote
Old Mar 17, 2012, 06:57 PM
Member 120mph Club
ATIS's Avatar
New Bern, North Carolina, United States
Joined Oct 2004
12,445 Posts
I hate to say this now but make sur they have a little forward rack on them to help reduce nose overs.... my ARF Skyraider likes to nose over on the stock gear.
ATIS is offline Find More Posts by ATIS
RCG Plus Member
Latest blog entry: maxford Nieuport 1/5th Scale
Reply With Quote
Old Mar 18, 2012, 08:53 AM
Now in TN!
J Morgan's Avatar
Chapel Hill, TN USA
Joined Apr 2001
24,337 Posts
Bryan,
I'm trying for a scale position if possible. I've read that thread about the noseovers. Guess I'll let Nut worry about that.

Decided to skin the wings first. I don't feel too confident that w/o the wing together with proper dihedral that I can safely set the LG spars and plate. Probably more work this way but hey, it's building and that's what I do.
So here is my skinning process:
I've skinned a whole lot of wings. Years ago I did what I had read. Get the skins, sand them, true up each edge using a long metal straightedge and exacto. Tape them together, unfold the seams and lay a glue line down, lay flat again and wipe off excess glue, let dry and then use epoxy, sorghum, etc to glue the skins on.
Wow, what a ton of work to glue balsa to foam.
I like building but I'm as lazy as the next guy. So skip all that you just read and just try one time this way and see if it works for you.
I used 1/16"x3"x36" lightweight balsa sheets( took about 16 for both panels) . First I made a newspaper pattern of the skin. Make it about 1/2" bigger all around than the wing panel. Started by laying one balsa sheet along one edge of the pattern and butted up the next sheet. Use low tack painter's tape( I like 3M, you get what you pay for, too tacky a tape and it can pull balsa grain with it when you remove it) and tape the seam while holding them tightly together.
Lay tape all along the seam. Same thing for the next sheet and so on. Finally you have a bunch of balsa sheets taped together and you can take a straightedge and trim to the paper pattern shape. One is done. Now this is important, TURN THE PATTERN UPSIDE DOWN to create the other sheet for the wing panel. You need a top and bottom, remember? Don't ask how I know this.
So do the same thing for the second skin and you have skins for one panel done. Easy.
Repeat for the other panel and you're ready to glue them up.
It depends on what time of day it is on how I do the gluing. I use brown Gorilla glue and spread a LIGHT skim coat over the whole skin( reverse side of the taped side of course) and lay in it's wing bed. Remember, Gorilla glue expands qite a bit and too much glue will try to buckle the skins. Do the same for the other sheet.
Now if it is early in the day, I use a damp, not wet, rag to wipe over the wing core. We just want a hint of moisture to help the glue set. Once both sides of the foam wing has been wiped, lay it in one bed making sure you have the same overlap all around. Carefully, so you don't move anything, place a ton of weights on the beds. Try to distribute it all over the top of the bed. Make sure you have them on a flat surface so you don't induce any warps in the beds.
That one is done, do the same for the other and let dry.
Like I said, time of day depends on how I glue them. If it's late in the day, I will forget wiping the foam cores down with the wet rag. It's not needed if you let them set overnight. If early in the day, I wipe them down so the glue will speed up it's curing process.
It's important that you only wipe a damp rag across the cores. If you get them too wet the balsa loves to soak up that moisture and can swell leaving ridges. Again, don't ask how I know.
So that's it. After a few hours you have completely dried foam skinned wings that are ready to trim and apply LE & TE.
Now as far as how long it takes vs the process I described before? I started making the paper pattern and one hour later I had both of them skinned and curing. This afternoon( or before) I will take them out of the beds and trim for the balsa LE & TE.
Try it, I think you'll like it.

J
J Morgan is online now Find More Posts by J Morgan
RCG Plus Member
Latest blog entry: OV-10A Bronco from Palmer Plans
Reply With Quote
Old Mar 18, 2012, 10:28 AM
Capt. Z
falcon5's Avatar
United States, NV, Las Vegas
Joined Dec 2004
2,568 Posts
Quote:
Originally Posted by J Morgan View Post
Try it, I think you'll like it.

J
Why yes I think I shall,

Good pics too, I see what you mean about the skim coat.

Thank you kind sir, great info.
falcon5 is offline Find More Posts by falcon5
Reply With Quote
Old Mar 18, 2012, 10:37 AM
Addicted to building...
Freddie B's Avatar
Omaha Nebraska
Joined Feb 2006
5,992 Posts
Very nice. Love the great explinations and photos give such great instruction. Back to the white foam issues. Since the white foams are made from beads that expand and stick together using steam, the beads will always somewhat pull out when sanding. Lots of airgaps form in between the beads too. So I like 60 or 80 grit to rough, and yes light pressure when sanding. The paper will cut the foam. I too try to wipe the block and blow or wipe off the foam often.seems no matter what it is very hard to get good finishes on white foam.

With all sanded foam lightweight filler is your friend, but still never perfect on the white foams. These foams are too soft and squishy. I do love blue and pink foam the best, but they do weigh a lot more. I can get a flawless finish on those foams, but they still need covering to keep it that way.

Guess we just have to deal with little problems since we are builders! Thanks again for all the great info and photos.

Fred
Freddie B is offline Find More Posts by Freddie B
Reply With Quote
Old Mar 18, 2012, 10:57 AM
Now in TN!
J Morgan's Avatar
Chapel Hill, TN USA
Joined Apr 2001
24,337 Posts
Your welcome Fred.
I will only use white foam if I am going to cover it with a harder finish. I don't like glassing bare white foam, to get a good finish requires a lot of work and it starts building up weight. But I love it for wing cores and some carved fuselages. With them I always skin with balsa and then you can easily get a great finish. Or carve a white foam fuse and then use it as a plug for a fiberglass fuse. I too prefer blue and pink foam but they are heavier and I don't like to use them for hot wired wing cores. Just have to pick and choose where to use it.

J
J Morgan is online now Find More Posts by J Morgan
RCG Plus Member
Latest blog entry: OV-10A Bronco from Palmer Plans
Reply With Quote
Old Mar 18, 2012, 12:01 PM
Now in TN!
J Morgan's Avatar
Chapel Hill, TN USA
Joined Apr 2001
24,337 Posts
So after three hours, I pulled the wings and trimmed up. They are both ready for LE & TE and it's not even lunch. Sweet!
You can see from the pics why I use low tack tape. It has pulled up some balsa grain "hairs".
So what do you do while waiting fro wing skins to dry. Start a canopy plug. Pics show the progress, still some shaping to do. I'll get back on the plug while the glue dries on the LE & TE.

J
J Morgan is online now Find More Posts by J Morgan
RCG Plus Member
Latest blog entry: OV-10A Bronco from Palmer Plans
Reply With Quote
Old Mar 18, 2012, 12:02 PM
michigan jet guy
mrshea's Avatar
USA, MI, Caledonia
Joined Jul 2007
1,083 Posts
i'm just using it to do a fuse plug and wing cores but was wondering if i was the only one having these problems. I'm gonna try this skinning method when i do the wings for my sabre. Thanks j. Phil
mrshea is online now Find More Posts by mrshea
Last edited by mrshea; Mar 18, 2012 at 12:03 PM. Reason: can't spell today
Reply With Quote
Old Mar 18, 2012, 05:44 PM
I don't do Normal
Pinky_d_brain's Avatar
Canada, NT, Yellowknife
Joined Dec 2011
453 Posts
Grate work J
About sanding foam don't no if any of you have tried this but the sanding screen used for drywall sanding works grate, You don't have to clean it as often. I use something like in the links, don't no if you can get this stuff but if you can give it a try.
http://www.homedepot.ca/product/hand-sander/903215
http://www.homedepot.ca/product/grit...5-yards/959659
Pinky_d_brain is offline Find More Posts by Pinky_d_brain
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Build Log TF 1/8th Scale P-47 Build; Going For Detail LuftM40 Fuel Warbirds 417 Nov 28, 2013 07:24 AM
Build Log Me-329 Build............ 1/8th scale J Morgan Pusher Prop Jet Models 1018 Aug 26, 2012 04:23 PM
Sold TMRC 1-26B NIB Kit - 1:8th Scale - $125 shipped CONUS John Walter Aircraft - Sailplanes (FS/W) 1 Jun 25, 2012 08:36 AM
A-1H Skyraider 60" by LEG - Build jcarstan Slope 64 Jul 22, 2005 12:43 AM