I'm a production sculptor for making props for miniature golf and have access to huge amounts of foam, and a 8ft wide cnc hotwire And have started to cut wing profiles airfoils gliders and such out of scrap for my own amusement. it's l moderate density "one pound" EPS foam just the basic white styrofoam, not perfectly ideal for airplanes i am thinking a bit more rigidity might come from a skin, and started experimenting with vinyl tape and strapping tape with the fiberglass strings in it. I like the idea of basically a full sheet papier mache as you've done. properties of certain foams prohibit interaction with certain types of glue that contain solvent. it's compatible with wood glue and water based craft glues and pastes and decoupage there's a lot of foam coating products out there and ways to do it but for something cheap paper is really smart. I'd like to find a paper that has fibers embedded in it straight lines and I could use those intentionally. I would mention that the less water in your adhesive of choice creates less problems with warping wrinkling and degradation of the material. The best foam adhesives are sprays applied onto both surfaces and allowed to dry then bonded. there's no repositioning, 😅 So it's a little challenging to work with. but if you encounter a spray adhesive specifically for foam you might try it out😊

@RC-Dorigas

26 күн бұрын

Thanks for your comment! Unfortunately, I have not tried other cheap methods to cover wings other than paper and (as you already tried) packaging tape. The spray glue seems interesting because of the faster application and cure time, however, I believe that since the paper expands once it has come in contact with the water/glue mixture and during curing it contracts back, the level of "tightness" achieved by this method is far superior to the one get with non-water based glues. Also, I add water because if not done so the glue would be almost impossible to spread out evenly quickly. Anyway, I encourage you to try every method that might seem better because maybe it really is! I will try the spray glue method on a test sample next time I power up the foam cutter to see the results. Cheers!

Excellent.

Thanks - good vid...will try it!

@RC-Dorigas

Жыл бұрын

You are welcome! Let me know if it works!

One of the best results I've seen so far. Is Elmer's OK. It seems Vinavil is not as popular in the US. Also You don't seem to use the negatives to sandwich the wing before curing, don't you get unwanted twist? Thanks!

@RC-Dorigas

Жыл бұрын

Thank you! I do not know if Elmer's will work, the glue I use is more specific for wood and paper, as long as it is a vinilic glue and you can diluite it in water i think it can be used after some testing. I do not use the negatives of the wing because doing that will affect the drying of the glue and the shape of the wing will not benefit from that. As long as the wing is covered in one take on both top and bottom and it's placed straight verrical not too close to walls it will dry uniformly and without bend or twist. A helping factor is the thikness of the wing: more thik = less possibility to bend/twist. I have managed to cover wings with one cm of thikness at the root and 50 cm long without noticeable warps but a bit of know how of the process is needed.

@EngineeringFun

Жыл бұрын

@@RC-Dorigas It certainly works, others are using it. However, your wing surface looks smoother than anything I've seen, without using using a light weight filler.

@RC-Dorigas

Жыл бұрын

@@EngineeringFun Good to know that! The material I use is an extruded insulating foam, once hotwire cutted the surface has a texture similar to orange skin. I think that the key is to sand very gently the surface (I use a 120 grit sandpaper) in order to smooth it out but more important to help the glue stick to the plastic because the surface gets less hydrophobic and the mixture of water and glue wets it out better. I think that without sanding I won't be able to get the same results. Be warned that while sanding the wing will bend because of the surface stresses on the skin, the sanding must be very light and uniform on all the wing otherwise you will have a banana before starting the covering process. Be sure to wear a respirator while sanding because the dust is very fine.

@EngineeringFun

Жыл бұрын

@@RC-Dorigas Thanks!

Looks very good! Does anyone know a water resistant alternative to this?

@RC-Dorigas

4 ай бұрын

Thanks! If you mean to use it on planes that land on moisty fields I can say that spray painting cured paper covered wings creates a very light waterproof skin that prevents water to be absorbed, I suggest to spray more light coats and let them dry between each other in order to prevent solvent buildup with the risk of damaging the foam. If your intention is to use it fully underwater like on the floats for a floatplane maybe a very light coat of epoxy can be used in order to create a fully waterproof skin around the paper. but at that point maybe fiberglassing the entire component might be a better idea. Let me know!

@eeropehkonen2370

4 ай бұрын

@@RC-Dorigas thanks for the tip. I've been thinking about doing quite a big wing. Ive done fiberglassing before but i find the process nasty and tedious. So im just thinking alternatives to to fiberglassing

@RC-Dorigas

4 ай бұрын

@@eeropehkonen2370 Well, if it's only for the wings I think the best option (also in terms of weight) would be to paint them. Keep in mind that if you feel the wing is too big for only one layer of paper, once the first one has dryed you can add a second one using the same technique, this in orderto not use carbon or plywood reinforcement spar into the wing.

What paper is used? Can this be used on a solid balsa wing? I can then find the equivalent in the UK.

@RC-Dorigas

10 ай бұрын

This type of paper can be found over packages in order to protect them during shipping. I find it in stationary store, usually cutted in big sheets and folded, but it can be also found in rolls. It is a fairy light but very stiff paper and as long as it has these proprieties it should be ok to use. I never tried it on balsa but I think that it could help a bit with the stiffness (making some test samples should help determining if it is a good choice and gain experience with the process). I think also that another option on solid balsa could be very light fiberglass laminated with epoxy. Let me know if you need more help!

I had to put mine back in the phone beds with weights overnight I'm not sure why but I kept getting warps... Maybe the paper or

@RC-Dorigas

Жыл бұрын

I have tryed several types of paper obtaining very good results but, with variations in the strenght of the final wing caused by the difference in the paper (weight and post treatments). From what I understand it seems that you have a different rate of drying between the top and bottom of the wing (try to hang it vertical from the root in an open area) or your paper has not been wetted out evenly ( it takes some time to do that and try to not rush the process ) Do not keep the wing inside the foam cores (beds / shells) during the drying process that is usually a good 8 hours but depends on temperature and humidity. Let me know !

Veiwed july 22

Laminating film is a better option.

@RC-Dorigas

2 жыл бұрын

For sure there are better ways to give foam wings more strenght, i found out that this method is easy and gives a good result.

@newventure4747

2 жыл бұрын

How about using a product called TYVEK ? It is crazy strong. Thanks for the idea. 💡

@RC-Dorigas

2 жыл бұрын

@@newventure4747 It's worth a try! unfortunatelly I do not know where I could find it but, if its relatively cheap it could be a nice substitute to paper. Let me know if you test it!

@newventure4747

2 жыл бұрын

@@RC-Dorigas Tyvek is usually what they make those non-rip fedex envelopes out of.

@newventure4747

2 жыл бұрын

@@RC-Dorigas Tips: The paper comes off much easier if you mist it with a water spray. The paper should be removed from both sides, then the tape applied, then bend. The results are better. If you leave the paper on, it will NOT be waterproof and even high humidity could cause it to peel off.