Need help with finishing a model...
 

Hi Guys,
I've finished building a balsa P-38 and I used .6 oz. glass cloth and epoxy to lay the cloth on. I'm ready to prim the model and plan on using Varathane, Polyurethane-water based clear-fast drying, and want to use talcum powder with the Polyurethane, to fill in the weave. How much talcum powder do you add to the Polurethane...? I already have the Polyurethane and want to get my model ready for the color coat.

Any advice will be nice...

Soft Landings Always,
Bobby of Maui

RE: Need help with finishing a model...
 

Bobby,

What I did when using the water based poly is to apply two coats of the poly over the fiber glass cloth. I then used an automotive filler primer paint like what you can get from Duplicolor. Spray on a heavy coat and try to avoid runs. Sand this down. Be careful not to sand through the fiberglass cloth. Then apply a second coat of primer. Wet sand this down and check the weave. If you sand through and rough up the fiberglass just apply some poly over it again and repeat the primer. You can then use some auto body spot putty to fill any areas you might want to smooth out.

After I did the two coats of primer I applied my panel line tape and used a soldering iron with a brass tube to lightly burn in rivets. This part seemed like it took forever. Spray the primer over the entire plane. When the primer is dry lightly wet sand until you can see the just see the back of the tape. Carefully remove the tape. Lightly wet sand any rough edges. This gives it a nice scale appearance if this is what you want to accomplish.

If you don't need panel lines, etc, you can paint after the first steps when you get the smooth finish you want.

I need to do the weathering now to complete the R4D-1.

Thanks...rotoman

RE: Need help with finishing a model...
 

Hi buddy,
Nice looking R4D-1...I've the Top Flight kit myself and its on the list of builds for me.

I've already have one to two good coats of sanding finishing epoxy over the glass cloth now. What I need to do is fill in the weave. A friend of mine here on RCU suggested I use water based poly...with talcum powder added...but failed to tell me how much talcum powder to add to the water based poly. I would like to use the water based poly with talcum powder...but if I can't find the right mix...I'll do my best and experiment a bit.

Thanks for the help,
Bob Paris

RE: Need help with finishing a model...
 

Is one of those things that you will have to go through trial and error. What you are looking for is to add until its the consistency of lets say pancake syrup. Use a good brush and go to work.

RE: Need help with finishing a model...
 

Watch for adhesion problems. You plan to switch from epoxy to waterborne poly.

You started with epoxy, why not continue with an epoxy primer ?

RE: Need help with finishing a model...
 

I don't understand the use of powder "over" cloth.

We originally used powder mixed with clear dope to fill the wood grain. We would apply silk over that and just use clear dope.

That process still works well today, especially if you elect to have colored silk as part of the design.

I've said this before and I'll say it again. I use no water base anything. I don't care if there's 1000 modelers, all of who have received awards for their finishing, agree it's the best thing since chopped liver.

I use no Epoxy on my glass cloth. Just Polyester resin. Couple of thinned coats does it, Scuffing in between coats. Automotive primers after that, and some are available in aerosol cans, and so is automotive paint.

You can detail the primed surface, till your eyes pop out, or just apply paint, for those that don't have spray equipment.

I apply all my paint lightly, just enough to cover, dust it on, because I finish in automotive clear.

Here's an award winning model I scratch built in the 80's. Took best finish at the WRAM show, and it still looks as good as new!

I'll never change my winning game.

RE: Need help with finishing a model...
 

Ok how many flights is on that bird? Look too good to not be a hanger queen. No fuel stains, wing tip scratches..chips..what gives?

RE: Need help with finishing a model...
 

[X(]:D

RE: Need help with finishing a model...
 

Hanger queen.

RE: Need help with finishing a model...
 

Rotoman,

Great looking model. Windows look real? Really real.

Could you detail how you acomplished this?

Good looking windows or is that some photo illusion?

Thanks,

Charles

RE: Need help with finishing a model...
 

I am curious about the brass tube and solder iron for rivets.  Ive never heard of that method.

RE: Need help with finishing a model...
 

Hi Everyone,
I wasn't sure if the reference of a "Hangar Queen" was about my R4D-1. I have been breaking in the new OS 35AX engines before she gets maidened this fall. The last thing I want to happen is have a one engine out situation on a new twin. I don't have Hangar Queens in my Squadron. I will video the maiden and get that up as-soon-as-possible. Don't know for sure when.

How to do rivets with a soldering iron is explained here: http: //www.strictlyscale.com/StrictlyScale/Tips.html Look under "Experiments in Detail and Finishing". This site has some great information.

At RCSCALEBUILDER.COM in the "General Section" under "Finishing" the most complete detailed information about all aspects of using and finishing fiber glass is there. This is where I learned the method I used on the R4D-1. You must register to get access to the forum subjects. It is well worth it. http://www.rcscalebuilder.com/default.asp

Reference to the windows on the R4D-1. I had a local graphics company print up new window decals to match those that come in the Top Flite DC-3 kit. They applied them for me, but they didn't look real enough so I took some of the small solder used for electronics soldering and cut and glued those around the windows to give the look of window moulding. I think it turned out good enough.

Up here in Minnesota we are blessed to have a great group of guys located in MN and up in the Twin Cities: Scale Flyers of Minnesota and MN BigBirds. http://www.mnbigbirds.com/ They only meet during the winter but their meetings a full of great show and tell and instruction. In Southeast MN we have the Northen Alliance Military Fly In sponsered by the Tim Johnson, his wife and the great guys at SMMAC located in Owatonna, MN. Well worth the trip. http://www.smmac.com/Southern_Minnes...b/Welcome.html

I think I've covered enough. If you have more questions go ahead and list them.

rotoman

RE: Need help with finishing a model...
 

WPBrown,

The "Hanger Queen," was directed towards my model, not yours.

Great job with the window effort, clever also.

Please keep us informed.

Charles