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Hi friends,
Let me share my experience how to force a pylon to match the wing perfectly quite easy and quickly.I used this technique assembling my engines PW and GE.
I show this by the example of my PW’s pylon and the wing of Revell 744 kit, but it can be used to attach any engine to any wing.The Revell 744 wing has humps for mounting engines.
In my opinion they are done in not quite correct areas.
The pencil lines show my vision of where they engines should be.
I cut off the bumps, drilled two small holes along the line of the engine, drew two more control lines and applied masking tape.
And the main trick, I put two small pins in the holes.
That’s all you have to do with the wing.
Now proceed to pylon.
I cut off the thin part completely, as it’s only for purpose of transportation so that the pylon does not lose its shape and not break.
Taking into account that the wings are V–shaped you need to cut off the part of the pylon that is closer to the fuselage at an angle of about 5 degrees.
That is the right side of the pylons on the left wing and
the left side on the right wing
Then I put the pylon to the wing in the right place and pressed it.
The pins remained in the pylon.
As you remember, I always mentioned them in my posts for good reason
I applied A LOT of putty on the wing. (BTW I never use a modelling putty
I use only finishing putty with hardener for cars!)
And put the pins of the pylon in the holes of the wing.
As a result I got the upper surface of the pylon completely corresponding to the surface of the wing.
When the putty was dry but had not yet become solid (10-15 min) I just cut the edges with a sharp lancet and slightly sanded in 30 min.
That’s all folks
The result
Thank for your attention
Sergey
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Amazing work! Very smart.
Thanks,
ahmed
KSFOI do something similar. Instead of tape I use bare aluminum foil. I also use sprue mixed with MEK instead of putty. Sometimes (or with resin) I’ll use CA glue mixed with dental acrylic. Both work well!
I’ll have to try the trick with the pins! Thanks for sharing!!
Chris
"Sorry Goose... But it's time to buzz the Tower."
I’m not sure I understand what you mean when you say “Taking into account that the wings are V–shaped you need to cut off the part of the pylon that is closer to the fuselage at an angle of about 5 degrees. That is the right side of the pylons on the left wing and
the left side on the right wing.”If the intent of this step is to make the pylons perpendicular to the ground, I think you are incorrect. I was under the impression that most big jetliners have their engines mounted so that the pylon is perpendicular to the wing, not the ground.
Aside from this, the technique appears sound. I’ve done something similar mounting fins to vac-form models.
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Same for Airbus ( here A340), druzz is right:
https://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Virgin_Atlantic_%28G-VWKD%29_Airbus_A340-642_at_Sydney_Airport.jpg/1024px-Virgin_Atlantic_%28G-VWKD%29_Airbus_A340-642_at_Sydney_Airport.jpgGérard
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I guess Airbus has a different design philosophy.
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I think the forces would be enormous to keep an engine of that size tilted like that. Hanging straight down makes more sense to me.
Thanks,
ahmed
KSFOGreat work druz.
I always look for a reference photo for mounting engines.
I think zvezda has engineered engine mounting on wings very nicely.
Cheers
Andrew
CYYZHello friends,
I would venture to suggest to your attention one more magic simple way 🙂
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Thanks for demonstrating your technique, Sergey. It seems that a few of us have run into variations on the same problem and arrived at different ways to fix it.
-d-
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What I don’t get is how the pins are transferred to the pylon. If you press the pylon down on the wing with the pins mounted to the wing. Pressing down would push the pins farther into the wing. Could this step be explained a little clearer.
Thank you
Jaime Diaz
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Hello Jaime,
The pins should be of such a length that they touch the plastic of the upper half of the wing.
In this case they will not fall through farther but will remain in the pylon.
I’m using dental reamers.
First I insert them where it is necessary,
then cut down with cutters to the desired length
and turn upside down
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I recently tried this method on my latest project and created a colossal mess. I’m not understanding several steps that maybe any of you may be able to help with. I used small parts of brass rod and when trying to press the engines down onto the wing to get the pins to stick into the engines, they went through the bottom of the wing. Not good. As for the putty, I’m using the 3M blue automotive putty and used a fair amount as detailed in the above posts but could not get the putty to fill the necessary gaps that need filled. So basically I’m back to square one with pins in now the bottom half of the wing. Wish there was a video on this site so as to see this method as it’s done and maybe that will help me with this. Any input and or help you all can provide is much appreciated.
Mark
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I recently tried this method on my latest project and created a colossal mess. I’m not understanding several steps that maybe any of you may be able to help with. I used small parts of brass rod and when trying to press the engines down onto the wing to get the pins to stick into the engines, they went through the bottom of the wing. Not good. As for the putty, I’m using the 3M blue automotive putty and used a fair amount as detailed in the above posts but could not get the putty to fill the necessary gaps that need filled. So basically I’m back to square one with pins in now the bottom half of the wing. Wish there was a video on this site so as to see this method as it’s done and maybe that will help me with this. Any input and or help you all can provide is much appreciated.
Mark
Hi Mark,
When you say they went through the bottom of the wing, do you mean they fell in, and are now making baby rattle sounds? It sounds like the rods were not long enough to “bottom out” against the inside of the upper wing surface.
It’s worth pointing out too that while the idea of more locator pins sounds better, a new problem arises in the form of being able to hold tolerances close enough to where 4 holes will match up exactly. Usually this is not the case and at least one hole would normally need to be opened out a bit to allow for some “wiggle room”. Not saying this is a bad idea, but i am saying this is a contingency to be aware of.
Unless i’m missing something here, whether the pins remain in the lower wing plank, or the top of the pylon, or if they come out at some point in the evolution i think is irrelevant. I’d say what matters first and foremost is that the locating points are correctly located on both the wing and pylon, so the engine can be repeatedly installed, fit checked, removed, adjusted, re-installed, etc. during the gap filling and clean up process. Personally i want the locating pins in the pylon….or be fully removable because i don’t want them in the way during the sanding or painting phases. I build and paint my engine nacelles separate from the rest of my model if i can.
Brass rod is a good material to use for the pins. If a pin gets stuck in either the wing or the pylon it can usually be pulled out with a needle nose pliers or a vise grip.
3M Blue Putty is great stuff, but IMHO not well suited to this application since its kinda thick and it doesn’t really “flow” into gaps. Druz’ new posting from June 11 more closely resembles my technique, the main difference being that i use clear plastic packing tape instead of masking tape (it’s thinner). For the gap filler, he suggests CA and Baking Soda. Over time Baking Soda can turn black and possibly do other crazy things i don’t know about. My suggestion would be to use CA, but instead mix in either talcum powder or acrylic dental resin, and i let it air dry for a while (perhaps an hour) before i hit it with accelerator.
It’s important to get the pylons off the wing and sand away the excess CA promptly, because the stuff usually gets harder with time. I don’t let mine sit longer than a couple of hours before i sand on mine. You also need to use rigid backed sanding sticks of sufficient coarseness to take away the hardened CA, yet not accidentally chamfer the mating surface where pylon meets wing.
I can elaborate on my technique if necessary, but i don’t wish to upstage Druz’ efforts here.
david
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