Thread Tools
Aug 06, 2007, 12:13 PM
RC 4 Life
sparks's Avatar

Plastic detail


Since my fuselage frame went together like Pats I see no point in posting it.
It's plenty strong enough to put up with the forces shrinking Ultra Cote will do. I feel that Ultra Coat is sort of a compromise between the Nelson stuff and Monocote. ( thickness and weight)
I'll detail the plastic assembly though.
I started with the cockpit. Trim right up to the combing (SP?) and sand the edge smooth.
Retain as much material as you can around the outer edges. Place the cockpit cover on the frame and center it using the lower stringers with the pilots combing. pull it back until the ends of the aft stringers are covered. Tape it down and mark the inside of the cover with a pencil along the bottom. Keep the forward material.
Use the forward top edge of the frame side( pencil point ) to locate the side panels position. (Marked on the panel) The aft upper step in the side panel goes under the cockpit cover. Note the notch cut in the cover to accept the side panels thickness. tape it down and mark it for trimming. . . .keep the forward edge plastic for now.
More tomorrow.
Sign up now
to remove ads between posts
Aug 06, 2007, 08:05 PM
Neophyte hacker
portablevcb's Avatar
Sparky,

Have you looked at Solarfilm? Wondered how much different it was than UltraCote.

charlie
Aug 07, 2007, 06:52 AM
"Have Glue - Will Travel"
dawnron1's Avatar
Quote:
Originally Posted by portablevcb
Sparky,

Have you looked at Solarfilm? Wondered how much different it was than UltraCote.

charlie
Thanks guys for all the nice comments, I absolutely loved shooting this one. The Jenny is such a photogenic model that it makes it hard to take a bad picture

Charlie, I was going to suggest the same thing. It's lighter than Ultracote but a whole lot easier to work with than Solite or Nelson. Hard to find it here, but I know that Horizon Hobby and Stevens Aero carry it.

Ronnie
Aug 07, 2007, 07:43 AM
Neophyte hacker
portablevcb's Avatar
Ronnie,

These slower airplanes are nice to take photos of. Even with my cheap camera I get good pics.

Yeah, I get it from Stevens. Hobby Lobby also sells it under another label, but, I forgot what it is But, I think they might have discontinued it because I can't find it on their web site anymore.

I do still like Solite for a lot of my planes though. I actually like working with it best, as long as I remember to change blades in the knife often enough

charlie
Aug 07, 2007, 10:39 AM
RC 4 Life
sparks's Avatar

cowl


Lets call the cowl top area just the cowl... . . . .
The front of the cowl is the end with the step molded in . This step is to be placed with it's inner edge over the F-1 former. Slide the cowl in place until the step it is butted against F-1 carefully trim the aft end until the edge mates with the step in the cockpit cover.
Cut the holes for the cylinders, I used a rotary file to do the rough cut and Dremmel sanding drum to take it to final trim. From there a few strokes with rolled up 180 grit sand paper will knock off the melted plastic buggers. Yes buggers, Find a better name and I'll change it.
Use the cylinder holes and the underlying stringers to center the cowl left to right.. Trim the cowl so the lower edges match the side panel steps.
Last edited by sparks; Aug 07, 2007 at 11:09 AM. Reason: photo
Aug 07, 2007, 10:55 AM
RC 4 Life
sparks's Avatar

trimming the plastic for assembly


Sand paper trimming. . . .again Find a better name and I'll change it.
A few parts will require precision trimming, the cylinder head is not one of them but we will use it for practice.
Place a sheet of 180 wet dry sandpaper on a flat surface. Give it a shot of water with a spray bottle. Wet sand the back of the cylinder head Appling even pressure until it becomes thin.
You can track your progress by holding it up to a bright light. As the material becomes thinner apply less pressure. Give the scrap a tug from time to time to check if it has broken through, It can trick you. if you have a spot being stubborn, a nick with a hobby knife will finish it off.
OK now you are checked out on sandpaper trimming. Do the rocker arms next , you will see how well it works on detailed trim jobs.
The exhaust manifolds are tougher because they have to mate up to bond them together. do your best to have them break through evenly. When I form them I use three pairs of tools. There is a chance that the halves are not interchangeable. They are formed as perfectly matched mates so mark the inside with a pencil so they can be paired up after they are trimmed.
To apply model cement to the edges I squeeze out some on the table top and spread it with a card. Then dip the edges in the thin puddle of cement. Do your best not to make a mess with glue on your fingers. Changing hands while adjustments are made and wiping off your fingers will do fine. Allow the manifolds to dry over night. This is a solvent bond, trying to sand the seam early will only produce solvent melted buggers. Ha, I worked it in again. Johnny Fever would be proud.
BTW the pilot assembles like the Manifold. Align him at the head first, Match the goggle straps and the rest should fall in place.
Aug 07, 2007, 10:57 AM
RC 4 Life
sparks's Avatar

Assembling the motor.


Go light on the cement after all it bonds by melting the plastic.
I don't recommend CA adhesive.
I don't recommend CA adhesive.
It's brittle and kicker will react with the plastic and cause surface cracks. Try it on scrap while it is bent. Bending it will simulate light stress on the plastic, 100 times less than a formed part has.
Trim the cylinders at the base, get it close along the cylinder side that faces the bottom edge of the cowl or it will interfear with the cowl fit. Bond them to the cowl. Bond the rocker arms to the head so the tips align with the pushrod cut outs. Drill holes in the cowl so you can put the rocker arms in place. I used small aluminum tubeing.
To trim the radiator, lay a pencil on the table and make a line around the bottom. There you go, sissors will work fine here.
Last edited by sparks; Aug 07, 2007 at 11:04 AM. Reason: Photos
Aug 07, 2007, 05:33 PM
Registered User
SKY KING's Avatar
Sparks,

Having just read about another E-zoner using his fingers to apply Balsaloc, can't help but wonder if your doing the same with the silver paint..
Aug 07, 2007, 06:06 PM
Neophyte hacker
portablevcb's Avatar
And I thought he just got sloppy with the fingernail polish

charlie
Aug 08, 2007, 10:11 AM
RC 4 Life
sparks's Avatar
That's primer on the thumb nail guys the Automotive type. It's no secret, I'm rough on equipment that goes for my hands too. It seems that with each model I build a little of it gets on me and it carries away a little DNA too. Normally blood but on good days just a drop of sweat or two.
So tell me, do you guys use those little dainty micro mark part holders when you paint small parts? I don't have time to look for shop gadgets. Shoot it, set it down to dry and move on.
You are a daisy if you don't.

Lets attach the panels. . . . . . . . .
If I cant use CA to attach the plastic to the frame then what?
Epoxy will work but it would be very messy. I'm not sure what Pat used, Hopefully he has an alternate for you. I used sylicone. I put some in a sanwitch bag, cut off the corner makeing a very small hole in the bag and applied it like decorating a cake along the stringers and formers. It takes a while to set and buys time for adjustments. It holds firm but the plastic can be pealed off without damagging the part or frame. I know because I had to remove the radiator once already.
Tape every thing in place and allow it to dry.
Dont forget to scrape off the paint where the Exhaust manifold attaches. model cement does not bond paint well
Aug 08, 2007, 12:07 PM
Gravity is a harsh mistress.
Tim Wolff's Avatar
Canopy glue ought to work for holding the plastic in place. Debonds with water too.
Aug 08, 2007, 12:14 PM
Neophyte hacker
portablevcb's Avatar
Yep, I use canopy glue and silicone for attaching things like this. Silicone when I want to take it off, like cowls, or when I want a lot of flexibility, like wheel pants.

charlie
Aug 08, 2007, 10:44 PM
Registered User
P. Tritle's Avatar
Thread OP
That's primer on the thumb nail guys the Automotive type.

Sparky, I do the same thing. Who's got times for allot of fooling around. Besides, it keeps your thumb nail from rusting when you're doing a lot of wet sanding.

I tack glued all the plastic on mine with small drops of medium Cya. You can get it apart if necessary, but it won't fall off -- and it's quick. I did glue the windshields in place with canopy 560 though. Getting them positioned properly is a bit tricky, and can clean up the smears with plain water.

I do use a good bit of silicone too. The aileron servos are always siliconed in, and it also makes a good glue for motor mounting from time to time. But for gluing in hinges, my personal favorite is still Canopy 560.

PAT
Aug 09, 2007, 03:29 PM
RC 4 Life
sparks's Avatar

cooling the old girl


This is as good a place as any to show where I started drawing outside the lines.
I wanted the radiator to be opened up for air flow so I attached window screen to the back of the plastic radiator.

I cut the center out of the radiator and used the "hole" to make a light ply pattern.
The screen was cut 1/4 inch larger than the Light ply pattern and was marked.
I used the marks to align the screen with the radiator and motor installed.
Then marked the motor shaft location.
I made a ply wood washer with my dremel motor and used CA to attach it to the screen material.
Aligning the "radiator hole" marks on the pattern My light ply piece became a bending tool.
With the screen in place I used the pattern as a clamp plate now to hold the screen flat against the radiator inner edge.
30 min. epoxy is poured into the plastic radiator frame and allowed to flow around with a little help from a stick. You only need enough to catch the wires.
A little flat black paint and the job was done.
Aug 09, 2007, 04:27 PM
Neophyte hacker
portablevcb's Avatar
I love all these building lessons. I always learn something I had not known before. Now if only I can remember it for next time

I also learned why I have a box of nitrile gloves too. Don't really like picking spray paint off my fingers

charlie


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Curtiss Jenny plans PROACE Fuel Plane Talk 1 Feb 28, 2008 10:13 PM
Question Looking at 60" racers; Nemesis and Mini Dragon e-sailpilot86 Slope 1 Dec 15, 2002 05:01 AM
FS- Curtiss Jenny kit CAWayne Aircraft - Electric - Airplanes (FS/W) 2 Oct 14, 2002 03:12 PM
Anybody built/flown the Dare Curtiss Jenny? Pork Tornado Scale Kit/Scratch Built 37 Oct 13, 2002 08:53 AM
TM maiden flight ends at 60' robs Parkflyers 16 Jul 18, 2002 08:52 AM