Just finishing up covering my Kadet, and was wondering if a person shrinks up the covering to the low shrink temp initially, or leave it. I have it applied to the glue temp, then went up just enough to get the wrinkles out and I'm still a good 60-70 deg F below the lower shrink temp.

thanks

flynte

I use only enough heat to pull out the wrinkles. Save the rest for later when it starts to loosen up again.

Thanks for the help, the best highlight in the build I got so far ( first plane) was finding the sweet spot on the iron for putting on the covering.

flynte

You will get 10 different stories probably, but keep this in mind...

You want some shrinkage initially....

The shrinking pulls everything together and gives the wing rigidity (i couldnt belive the diffence on my first build, i could flex the wing 20ish or so degress twisting it before i covered it, and none at all after it was covered)

Thats why alot of wings are built so light these days...you couldnt do that with fabric or anything other than the covering we use today..

The way I do covering is to tack down the edges of the piece with an iron, poke a few pin holes to let out air (this is on a solid foam wing, with a built up wing you dont really need the pinholes) then shrink the covering with a heat gun 3-5 times (let it cool between shrinking), on the last shrinking I press it down with a glove/cloth working any bubbles to the pinholes(careful it will be hot) this results in a smooth finish that will not need additional shrinking through the year.

That is a nice looking plane. At this point I set the plane outside in direct sunlight. Let it set a half hour or more. Iron any areas that wrinkle until they are smooth again. I don't use a heat gun now because it covers too large of an area. Set the plane in the sun again and repeat until there are no more wrinkles. Your plane should stay tight for a long time and won't look like a prune it's first day on the flight line.

You've done a great job, that's a pretty looking airplane![sm=thumbup.gif][sm=thumbup.gif][sm=thumbup.gif]

I can't give you any advice, it allready looks much nicer than anything I've covered.[&:]

I understand that a lot of you want to get a tight covering job, but some of the things listed above are actually making more work for yourselves than is needed. Getting monokote tight the first time through is actually a pretty easy thing to do, although it's easy it can be a bit time consuming. And on that note let me say this, don't ever be in a hurry when covering a plane. I've had lots of people ask me if they are doing something wrong because it takes them so long to cover the plane. Nope, not at all. Covering takes a long time. There are no short cuts or work arounds, you just need to take the time to get it done properly.

A couple of points first. On wings that have open bays. You will want to create a pathway from each bay out to the "open air". Look at each wing bay and see if there is a way for air to escape from that bay. You want to make sure that there is a path all the way from each wing bay out to the edge of the wing. If there isn't an open use a pin to create a small hole. It doesn't need much. Why are we doing this? Because trapped air is one of the biggest causes of your covering being loose. If the bay is completely sealed off what happens when you try to cover it is that the air in that bay will heat up and expand, and then when it cools down and deflates the covering will be loose again. If you have a hole in that bay the air in that bay will simply expand out and equalize letting you shrink your covering with no problems.

It was mentioned above that they poke holes in the covering when covering over sheeted or foam wings. Try to use this as a last resort. Trust me, it's possible to put down your covering without having to poke holes in it. Like I said above, it takes some patience.

Here's how I do my covering. First put down your covering on the panel that you want to cover (we'll discuss a wing here). First tack down one corner of the covering. Go to the other corner on the same side and tack it down. Before you tack down the covering in this corner you will want to pull the covering tight before you tack it down. When you pull it tight you will want to make sure that you pull straight so that you don't add any weird creases into the covering. One note here, don't worry if there are wrinkles in the covering at this time because they will work out (trust me, they will). Once you have this corner tacked down go to the next corner and once again pull it snug and tack. And finally do the same for the last corner. Is it important to pull it tight and snug right now?? Only if you want a tight covering job when you are finished. While it's true that the covering material will shrink when you heat it there is a limit to the amount it will shrink. The tighter you can get it now, the less shrinking it will take. One note here, as you are stretching the covering you don't want to warp your wing as you do it. This comes with practice on how much you can tug on it right now. With all 4 corners tacked down now we want to continue tacking down the edges. First go to the top of the wing in the middle of the covering and tack it down. Go to the bottom of the wing opposite of the last tack we made, pull the covering tight, and tack it down. Continue in the method until you have the covering fairly secure in position, and it's pretty tight. Now use your covering iron and go completely around the outside of the covering are and seal the edge down. This is very important that you do this because so that the covering has an anchor to stretch against. If you have a portion not sealed when the the covering starts shrinking it will just pull the covering out of position, and make a mess.

With the edges completely sealed it's time to start shrinking the covering. Use your heat gun to shrink the covering. Start in the middle of your work area and start heating the covering. You'll be able to see it shrink as you go. Don't get in a hurry here and work your way towards the outside of the work area. If you are trying to pull out wrinkles in the covering you will want to start heating AWAY from the wrinkles. Start heating the covering and then work toward where your wrinkles are. This will start pulling the covering tight and start to pull the wrinkles out before you ever get to the wrinkles.

After you have the covering shrunk with your heat gun now it's time to use your covering iron to seal the covering down. Use a hot sock on your iron so that you don't scratch the covering was you do this. Set the iron to the temperature that is recommended by the manufacturer. Start heating the covering and apply pressure to seal the covering down the the surface of the wing. On open bays use the iron to heat the area and finish shrinking it. As you use the covering iron, if you develop an air bubble use the point of your hobby knife to poke a small hole in the bubble, and then use the iron to push the air out of the bubble.

Look at the attached pictures to see what I am talking about. If you do your covering like this you won't have hardly any problems with it wrinkling up at the field or while stored. I store my planes in my garage and with Oklahoma summers the temps out there are usually 100°+ during the summer, and I don't have any problems with the covering wrinkling back up.

Please feel free to PM me if you have any questions about this.

Ken

Ran out of room for pictures. Continued here.



Ken

Good grief, Ken! I have little to add! I can only reiterate the fact that it's very important to apply as much tension to the covering as you can and get as many of the wrinkles out as possible, before shrinking the covering. This goes along way to wards alleviating having to remove wrinkles at a later date. Also, I agree, covering is a labor of love, take your time and get it the best you can to start with.

Now, if someone would only explain how to get those really fancy covering jobs done!

Ken?

Which fancy covering jobs would you be referring to??? Let me know what you want to see and I'll be more than happy to put the info out as best as I can

Ken

Hey Ken, those pictures would look great in the PIF LT-40 build thread. Even looks like the same color, how convenient is that?

Mode One,
Before I discovered how good RCU is, Faye Stilley's books helped me understand some of the fancy stuff. I would buy them again today.

RCKen,
Thanks, great info.

Ken,

How bout a tutorial/advice on how to have multiple colors on wings where the color changes over an area that's not sheeted? What do you do then? Apply a base covering to the entire wing first, then add additional layers? Or is there a way to "join" pieces of covering before applying to the wing? How do you tackle these types of covering jobs?

Thanks!

Master Alex, I am in the process of doing a video "How To" that covers exactly what you are referring to. I would have had it up by now, but a few other projects got in the way.

As Mike said, those things are in the works.

But in case you can't wait. There are two ways to do what you ask. The first is to lay down a base layer of one color, and then to put the second layer over it. It's best to put the second layer on using the "Windex Method". Instead of me re-typing how to put on monokote with windex I'll put this link up. This is an excellent "how-to" on doing it with windex, [link=http://www.rcuniverse.com/forum/m_603331/anchors_603331/mpage_1/key_flag/anchor/tm.htm#603331]Applying monokote graphics with windex.[/link]

The second way is to actually join your two color pieces before you put them on the plane. Get a mirror or a sheet of glass to use to join your pieces. Lay down the first piece on the glass and then position the second piece overlapping the first (about 1/4" overlap) and then use a covering iron to seal the two pieces together. Then you can apply those to the plane as you normally would put monokote on.

Hope this helps

Ken

Video ... can't wait for that one! Thanks MinnFlyer.

RCKen -

Thanks for the direction. I'm leaning towards large LE to TE stripes on the bottom of my SSE to help with orientation. I was thinking that it would be a waste to cover the entire bottom surface and then "re-cover" 1/2 of it again with a different color.

However, from a "degree of difficulty" perspective, is there a big difference in the 2 methods? They both seem straightforward - but the "joining" method seems like it could be a bit difficult.

Thanks for your help!

-MA

MasterAlex,
Yes, joining the two prior to putting it on the plane is more difficult. This is because it's hard to keep the line between the two colors in the place where you want it. It's also possible to have the line "warp" as you heat it. If you're just starting to use monokote it might be easier to just lay down the second color using windex.

Ken

Thanks for taking the time for your good post Ken, very informative. The one step I didn't use was shrinking with the heat gun after sealing the edge. I went with using the iron to get the wrinkles out. I can see where the gun would have been an excellent tool for that. Had one sitting on the shelf and never thought of it. I also missed putting pin holes between the rib bays, hope it doesn't cause to much trouble. As this is my first trainer I'll probably have some work to do to it. I am semi satisfied with the turn out, one of those jobs that looks good from afar, but far from good. I did pick up some techniques from this first go at it and from the help from the group I look forward to the second plane.

flynte