A Quick Tutorial for Iron-On Masking Approach

I’ve been protecting RC fashions for about 35 years. I picked up on Monokote again within the mid-80’s and tried it for the primary time. It took a little bit of studying curve however I bought the cling of it. Through the years I refined my method to incorporate fixing errors I made at first and saved enhancing issues as much as the current day. A few years in the past I attempted SolarTex and LOVED utilizing it. I thought of it my favourite protecting of all. However sadly, 2 years in the past SolarTex determined to hold it up and closed their store. This left a BIG void in the very best iron-on protecting on the market till OraTex got here out with a really appropriate substitute. They don’t have as many “flavors” as SolarTex did, however hopefully they may proceed to increase their line with extra colours.

I’ve seen numerous protecting jobs on the subject and a few are good and a few not. As all the time, there are often a couple of good builders who do nice protecting work. However as a rule, I discover most ARF’ers merely don’t “get it!” One drawback appears to be that these doing the protecting need to get in an enormous hurry to complete and their works present it. Masking correctly takes TIME and many it. One can not rush through this job. I’ll try to point out how I do the iron-on protecting job with OraTex Orange on a few items of the Prime Flite Hellcat Prepared-To-Cowl mannequin. My remaining coloration scheme is a post-WW II drone. Some say that the Orange depicted in some drone photographs from that period are incorrect and the actual coloration of the drones was Crimson. However there have been clearly some variations on the Hellcats that may additionally embrace a couple of Orange “Cats” as effectively. However that’s actually inappropriate right here.

As regular, my articles are primarily written for the newer RC pilots and builders. I understand many phrases have been spent on this topic, however like Western, Warfare, and Sci Fi films that preserve getting made and remade, there may be all the time a brand new viewers coming into view.

I’d additionally add that having a relatively LARGE provide of #11 blades is a superb thought. I purchase them by the 1,000 blade unit to verify I don’t run out. It solely takes a couple of cuts to boring a blade. So don’t make your self work more durable over the price of a couple of blades. You’re employed will seem MUCH SHARPER when altering blades out after a couple of cuts. It sounds wasteful nevertheless it’s vital.

Very first thing to have for any protecting job is an efficient protecting iron that may be adjusted from low to excessive warmth settings. OraTex tends to love decrease warmth settings so I had to purchase a brand new iron to exchange the one I’ve had 35 years and solely provides HIGH warmth!

Determine 1. Outdated and new irons. Outdated TF MonoKote iron on the left and new Hangar 9 iron on the suitable. I actually like the brand new iron! Notice the warmth setting about halfway on the dimensions. Good place to start out for OraTex.

After getting the iron set and whereas ready for it to heat-up, you could start slicing you protecting materials. On this article I’m protecting the horizontal tails and elevators, after which the middle wing part.

Determine 2. Horizontal tail and elevator of the Hellcat. That is the Prepared-to-Cowl instance which is nice for individuals who need one thing completely different from the group! Workmanship on these is very nice. They arrive able to hinge with Robart pin hinges.

Determine 3. Step one is to cowl the trailing edge to incorporate and overlap on each the higher and decrease surfaces. This overlap is vital so as to add because it retains the protecting from pulling off the balsa if the protecting is solely ironed on the balsa with butt joints. You will note how the overlap comes into play in a bit. Step one is to iron the protecting to the trailing edge.

Determine 4. A pleasant 1/4 inch overlap is usually recommended. Too little overlap and also you gained’t get the strong attachment to the protecting on the higher and decrease surfaces. It is best to calculate the full width of the strip to incorporate the overlap and minimize it on the work desk FIRST after which iron it on the piece. That manner, there may be little or no extra slicing to be executed and most vital, you gained’t be slicing into the balsa to trim the overlap.

Determine 5. Take the iron and press down on the overlap all the way in which across the floor. Be sure to not enable any wrinkles whenever you do that. When you get a wrinkle they’re laborious to erase!

Determine 6. When you get the Trailing Edge (TE) and overlap ironed on you could minimize materials for the higher or decrease floor. With a small overlap on the TE, iron the higher or decrease protecting on the TE ONLY and VERY CAREFULLY. The purpose right here is to get the protecting firmly glued on the TE and to not shrink the remainder of the protecting. Then lay the iron FLAT on the floor, however multi functional movement, sweep throughout the floor firmly. Do not forget that the iron is sizzling and when you depart it idle it’s going to start to shrink the protecting in an unpleasant method. KEEP the iron MOVING. This may glue the protecting right down to the balsa itself relatively than simply tacking the sides of the piece and shrinking the highest which isn’t a very robust protecting method. Do that sweeping movement all throughout the floor working towards the Main Edge (LE). It should take a number of brief passes to do the entire floor.

Determine 7. On the TE, take your #11 blade and punctiliously slide it down the TE and minimize away any extra high floor materials. However don’t let the blade dig into the TE protecting. It’s a good suggestion to do that with a brand new blade. With the overlap you created on the primary TE protecting, you now have a really robust bond between the 2 surfaces. Masking-to-covering bonding is significantly better than simply covering-to-balsa because the balsa is comparatively porous. Now, to not exclude ironing on the balsa as defined on the earlier step, as that may be a completely different state of affairs the place you don’t have any protecting to overlap.

Determine 8. After ironing the protecting down throughout the floor and across the LE, take the #11 blade and really flippantly minimize the protecting simply to at least one aspect of the height so you should have a small overlap. However DO NOT minimize with a lot strain! It’s possible you’ll be weakening the construction by doing so! It’s not so vital right here, however on different areas of the protecting job, it could be EXTREMELY damaging to construction.

Determine 9. The minimize is made and the protecting gently pulled off the floor.

Determine 10. The final half to trim is the rounded outboard edge. However first remember to iron the protecting PAST the centerline to the opposite aspect and THEN end the trim minimize.

Determine 11. Each Main and Trailing edges trimmed of extra protecting. These cuts don’t have to be picture-perfect as we nonetheless have extra to do.

Determine 12. Final trim minimize on this floor is the inboard edge. First, iron the protecting over the sting about 1/4 inch or so.

Determine 13. After which trim the protecting in a neat overlap. You don’t need to totally cowl this edge as it’s usually epoxied to the fuselage right here. So, by no means use epoxy over 100% protecting – recipe to catastrophe!

Determine 14. One aspect executed and one aspect to go!

Determine 15. With the other aspect coated like the primary aspect and trimmed, you possibly can (simply barely) see how the 2 coverings meet on the LE and mix collectively properly! However we aren’t executed but!

Determine 16. To maintain the 2 floor coverings from pulling aside within the warmth of the day on the subject, I add one other “overlap” of about 3/4 inch materials to maintain the 2 surfaces locked tight. Begin on the inboard edge and glue it down.

Determine 17. Ensuring you’ve got the overlap even on each side, proceed down the LE with the iron. The place the curved edge begins, watch out and slowly work the protecting across the curve. Small wrinkles might be smoothed out with the iron and gained’t present. I usually taper the final couple of inches of any curve with a small scissors to maintain the large wrinkles from forming.

Determine 18. Ultimate overlap is sort of invisible when you work slowly to maintain wrinkles out of there. Final trim is on the inboard edge. This remaining overlap additionally protects the LE from any gasoline that will get leaked out of the engine or gasoline tank. As soon as your protecting will get fuel or glow gasoline between it and the balsa, it’s going to begin to peel aside.

Determine 19. One horizontal tail is completed. Virtually seems prefer it’s painted when you work rigorously.

Determine 20. Now comes the elevator protecting. The elevator is finished barely completely different from the stab. First step is to cowl the LE with a big overlap!

Determine 21. Lower and add the highest or backside protecting to the LE first after which pull it tight and tack it over the TE. You don’t need it guitar-string tight right here, however attempt to preserve the fabric cosy as you possibly can with out warping the elevator. After getting it tacked to the TE, run the iron on high of the TE to safe it tight. Proceed across the curved finish of the elevator, pulling the protecting cosy as you go. DO NOT SHRINK the protecting presently! Wait until you’ve got each side coated and THEN shrink it rigorously. You possibly can nonetheless warp the piece by an excessive amount of shrinking.

Determine 22. Again aspect of the elevator after protecting one aspect.

Determine 23. Iron the fabric over the inboard finish after which trim as proven.

Determine 24. As with the horizontal stab, trim the surplus off the elevator with a brand new blade. Elevator ought to be as proven at this level. Notice that the protecting has not been shrunken. Proceed to cowl and trim the other aspect and THEN you could shrink the protecting on each side. However, don’t go loopy with the iron! Only a fast move or two on each side at first. Then enable to chill a minute and see if it has any sags. Contact it up as wanted with the iron. And I ought to have talked about on the first, use the iron for the entire protecting course of, not a warmth gun. Warmth weapons can burn through the coverings earlier than you realize it!

Determine 25. When you’ve got each components coated it ought to look “clear” just like the components within the photograph.

Determine 26. After which do the identical factor on the opposite horizontal tail!

Determine 26. Right here we’ve the middle wing part. Massive components are executed considerably the identical however with bigger strips of protecting. However there’s a restrict to how massive every strip ought to be as too massive a chunk will be laborious to deal with with out ruining it. First, cowl the cutouts for the flaps. Then transfer to the higher or decrease surfaces.

Determine 28. I laid out the fabric in 8 inch large strips. This makes protecting extra easy. As with the horizontal stabs, you iron the protecting on the naked balsa for a lot of the floor. You continue to have the overlaps across the edges. Ensure you have the protecting straight throughout the wing and never cock-eyed.

Determine 29. With one other 8 inch strip, add it on high of the earlier strip however with a 1/4 inch overlap. At all times transfer from aft to ahead with the protecting. Proceed to iron the protecting to the balsa as you go. Begin with ironing the overlap seam ensuring you might be straight throughout the wing after which iron the fabric to balsa.

Determine 30. With the final 8 inch strip, cowl the ahead a part of the wing with the identical overlap as earlier than. Trim out the openings rigorously and depart some extra protecting for use as proven within the photograph beneath.

Determine 31. Extra protecting left across the openings to iron onto the wheel wells, on this case. You possibly can return and trim these extra evenly when you like, however they gained’t probably be seen later. Or paint the wheel wells inexperienced Zinc Chromate to mix all of it in as one coloration. However the vital factor is to make sure that the ends are glued down effectively. You may additionally combine a little bit of Z-Poxy ending resin and paint it over the ends to actually lock them down.

Determine 32. Trim the sides like earlier than. Then transfer to protecting the other floor.

Determine 33. Prime aspect of the middle wing coated and executed. Prime aspect was executed precisely like the underside aspect in three sections utilized from aft to ahead.

The tip of the tour!

That’s the nickel tour of my iron-on protecting methods. There are all the time going to be completely different methods required when transferring to different components of your mannequin, particularly the fuselage. The fuselage is one space that you just DO NOT need to trim off protecting round sure areas over balsa utilizing a #11 blade! Chopping into balsa on sure fuselage components can result in structural failures. So, plan forward together with your coverings over delicate spots to complete with a straight minimize (made on the work desk) and finish with simply ironing it on with none trimming.

Maybe crucial characteristic of my protecting technique is all the time utilizing an overlap (the place doable and sensible) to maintain the items from pulling away from one another when the mannequin is within the warmth of the Solar. This may be with a easy 1/4 inch overlap of two sections of protecting or by including a separate overlap like I did on the main edges. Both technique works effectively.

When utilizing different coverings equivalent to Monokote, they have an inclination to require barely hotter iron settings, particularly going round curved surfaces. Regulate your warmth settings till you get one which works, however attempt to preserve from utilizing extra warmth than is definitely required.

Take your time. No have to be in a rush. This materials is pretty costly, so think-through every panel’s protecting utterly – measure twice and minimize as soon as. Additionally, take into account that craftsmanship is vital; NO, it’s EVERYTHING!