Model Merchant F-4 Phantom 1/2A Powered
09-01-2014, 06:11 AM
#1
Model Merchant F-4 Phantom 1/2A Powered
This plane is a styrofoam wing and vacuum formed fuselage. I have never built this type, but would like to do a good job on it. Airbrushing and all. The kit is a great start to something that wouldn't take much to make a really nice plane.
I've already studied up on how to treat the plain styrofoam wing. Vacuum bagging is out, so probably glass and expoxy over balsa skins.
Is there a better method than what they suggest as far as joining the two vacuum formed fuselage halves? Does it need to be polyester resin (fiberglass resin) and fiberglass? Would microballoons help with the forming and sanding of the seam if they are added before the tape is laid down?
I'll have to look into foam cutters to add lights? maybe pushrod channels cut for retracts?
PS as of todays date there is another kit of this for sale on eBay which i have no association with. I figured it was kind of rare that would happen, these kits arent around that much. The last picture I uploaded is from that auction. I do not have retracts for this plane as the one being offered has included with it. I looked at Robart prices and think I'll have to make my own so another aspect has to be learned how to do. http://cgi.ebay.com/ws/eBayISAPI.dll...E:B:SS:US:1123.
It's a worthy kit to put in some building time. I just don't know how to picture all the best routes to go with building it and thats where I could use some help.
I've already studied up on how to treat the plain styrofoam wing. Vacuum bagging is out, so probably glass and expoxy over balsa skins.
Is there a better method than what they suggest as far as joining the two vacuum formed fuselage halves? Does it need to be polyester resin (fiberglass resin) and fiberglass? Would microballoons help with the forming and sanding of the seam if they are added before the tape is laid down?
I'll have to look into foam cutters to add lights? maybe pushrod channels cut for retracts?
PS as of todays date there is another kit of this for sale on eBay which i have no association with. I figured it was kind of rare that would happen, these kits arent around that much. The last picture I uploaded is from that auction. I do not have retracts for this plane as the one being offered has included with it. I looked at Robart prices and think I'll have to make my own so another aspect has to be learned how to do. http://cgi.ebay.com/ws/eBayISAPI.dll...E:B:SS:US:1123.
It's a worthy kit to put in some building time. I just don't know how to picture all the best routes to go with building it and thats where I could use some help.
Last edited by jetpack; 09-01-2014 at 06:17 AM.
09-08-2014, 02:00 PM
#2
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Hmmm... Interesting kit.
I think I remember seeing the Hobby-Lobby ads in the magazines for this. My first question would be what do the instructions say for putting the fuse together?
My second question is what engine do they call for and/or what are you planning to put in it? When I think of 1/2A that means .049 size. You start putting retracts, epoxy finishes and fancy paint jobs and you can easily make it unflyable. So figure out how much power your going to have and start from there.
Without further information my first inclination would be to keep it as light as possible. If the plans or instructions don't call for sheeting the wing then your in for some redesign to account for the thickness of the balsa you use. That can get old quick if your just winging it or have to design around something you didn't account for.
Are the fuse halfs ABS plastic? If so, I would use plastic model building techniques. I recall using MEK and a very small fine tipped paint brush to apply it to the seams. You have to be patient as the MEK actually melts the plastic together. Check with a shop that carries supplies for plastic models. Also, I would avoid Microballons on plastic. Sometimes it works but sometimes epoxy doesn't stick well. In any case it always requires alot of sanding. Plastic models show every scratch the sand paper gouges out so you have to use very fine grades. I would use the filler the plastic modelers use. And like plastic models try to get the seams as small as you can before you glue it up.
For making channels in foam I just use a soldering gun. Take out the soldering element they provide and bend up the shape you want using K&N copper wire. A well stocked hobby shop should have the wire in different thicknesses. Use the thinnest you can get away with. use a couple pieces of spruce or bass clamped/bolted/screwed together across the wires to control your depth. Also bend your shape slightly smaller than what you need to allow for the heat "Kerf". When finished you can use different sizes of spruce or plywood to make sanding tools to clean up the channel.
Hope some of this helps,
Mike
I think I remember seeing the Hobby-Lobby ads in the magazines for this. My first question would be what do the instructions say for putting the fuse together?
My second question is what engine do they call for and/or what are you planning to put in it? When I think of 1/2A that means .049 size. You start putting retracts, epoxy finishes and fancy paint jobs and you can easily make it unflyable. So figure out how much power your going to have and start from there.
Without further information my first inclination would be to keep it as light as possible. If the plans or instructions don't call for sheeting the wing then your in for some redesign to account for the thickness of the balsa you use. That can get old quick if your just winging it or have to design around something you didn't account for.
Are the fuse halfs ABS plastic? If so, I would use plastic model building techniques. I recall using MEK and a very small fine tipped paint brush to apply it to the seams. You have to be patient as the MEK actually melts the plastic together. Check with a shop that carries supplies for plastic models. Also, I would avoid Microballons on plastic. Sometimes it works but sometimes epoxy doesn't stick well. In any case it always requires alot of sanding. Plastic models show every scratch the sand paper gouges out so you have to use very fine grades. I would use the filler the plastic modelers use. And like plastic models try to get the seams as small as you can before you glue it up.
For making channels in foam I just use a soldering gun. Take out the soldering element they provide and bend up the shape you want using K&N copper wire. A well stocked hobby shop should have the wire in different thicknesses. Use the thinnest you can get away with. use a couple pieces of spruce or bass clamped/bolted/screwed together across the wires to control your depth. Also bend your shape slightly smaller than what you need to allow for the heat "Kerf". When finished you can use different sizes of spruce or plywood to make sanding tools to clean up the channel.
Hope some of this helps,
Mike
Last edited by optech; 09-08-2014 at 02:08 PM.
09-10-2014, 05:44 PM
#3
What a disappointment. At least I got to check out the kit before it all gets sent back. False description in the listing. The two fuse halves have been joined together and the engine mounted. No instructions.
I would have not built the fuse the way it is done, that is for sure. It's very weak how it is done, plus the fiberglass resin heated up and deformed every inch of the seam. The two fuse halves were joined before trimming, then resin and glass tape used on the inside then the excess plastic was trimmed flush leaving just a small bead of resin and 1/2" tape holding it together. I heard it crack when I picked it up the first time.
I got a no hassle return, full amount plus shipping. I still hate being lied to and having to spend my time and energy to send it back plus the let-down of not owning it.
The pics will show everything thats in the kit. Without the directions I still dont know its wingspan or anything. The previous owner left a Cox TeeDee .051 crankcase assembly with it. It's damaged, wont turn over and there is a piston skirt dent on the backplate.
The foam wing turns out to be small skins of 1/8" or so meat tray type foam all packaged in the brown paper. Theres balsa ribs which they are formed around and a dowel is used as a spar. The trailing edges are balsa stock. Leading edges for inboard and outboard wing panels are there along with the tips.
The tail is all balsa sheet, nothing fancy there. It looks like the rudder and elevators are all designed to just be glued and an elevon type control used on the wing. Not sure what surfaces are controlled.
There's a couple of clear wind cheaters to place in front of the intakes I thought were kinda neat. The decals are still snow white and look usable. The engraving was all done on the male plug which the plastic is pulled down on. Just enough there for a detail pen to follow, but carefully. The surface detail is really nice on it. The nose cone comes right up to the prop plate perfectly when slipped on but the engine has alignment problems. I love the trick little motor mount stamping. I would like to know who made those and who has more.
If the fuselage and the instructions were not a problem, I would be happy with the kit and probably will be sorry I returned it later on.
I would have not built the fuse the way it is done, that is for sure. It's very weak how it is done, plus the fiberglass resin heated up and deformed every inch of the seam. The two fuse halves were joined before trimming, then resin and glass tape used on the inside then the excess plastic was trimmed flush leaving just a small bead of resin and 1/2" tape holding it together. I heard it crack when I picked it up the first time.
I got a no hassle return, full amount plus shipping. I still hate being lied to and having to spend my time and energy to send it back plus the let-down of not owning it.
The pics will show everything thats in the kit. Without the directions I still dont know its wingspan or anything. The previous owner left a Cox TeeDee .051 crankcase assembly with it. It's damaged, wont turn over and there is a piston skirt dent on the backplate.
The foam wing turns out to be small skins of 1/8" or so meat tray type foam all packaged in the brown paper. Theres balsa ribs which they are formed around and a dowel is used as a spar. The trailing edges are balsa stock. Leading edges for inboard and outboard wing panels are there along with the tips.
The tail is all balsa sheet, nothing fancy there. It looks like the rudder and elevators are all designed to just be glued and an elevon type control used on the wing. Not sure what surfaces are controlled.
There's a couple of clear wind cheaters to place in front of the intakes I thought were kinda neat. The decals are still snow white and look usable. The engraving was all done on the male plug which the plastic is pulled down on. Just enough there for a detail pen to follow, but carefully. The surface detail is really nice on it. The nose cone comes right up to the prop plate perfectly when slipped on but the engine has alignment problems. I love the trick little motor mount stamping. I would like to know who made those and who has more.
If the fuselage and the instructions were not a problem, I would be happy with the kit and probably will be sorry I returned it later on.
Last edited by jetpack; 09-10-2014 at 06:00 PM.
09-10-2014, 05:53 PM
#4
Mike I certainly appreciate all your advice. Thank you! I've read a few articles on how to properly make a scale vacuformed plastic model airplane. There's a couple tricks about doing it properly. This kit is a fun project because of the multi-media materials. After looking at the kit, if it were acceptable to swap out the foam with balsa I certainly wouldn't think twice about it. There isnt much wing area there plus all the weight savings needs to be done with the fuselage. I would go thinner with the plastic and add a balsa bulkhead here or there where needed instead.
