Thanks, I actually have made a newer version since I made this video, but it is still the same concept. The next time I set it up to cut some cores I will make a video of how it was built. It might be a while though I am having surgery and will layed up for a while.

@@donolson6335 Good luck with the surgery - I look forward to more engineering elegance!

I'm still waiting for your reply

I think you are confusing dollar tree foam with hot wire cut wing cores. the idea here is to cover hot wire cut wing cores with paper not to remove paper from dollar tree foam.

@@donolson6335 yes you're right, my mistake.

Well the 3 boxes he did is equivalent to 33%. I'm not sure if that will work for swept wing. I will only believe if he flies 3 different wings with that set up

Totally agree , there's no way that this method is correct. CG will be further back than that.

If this worked, why would you even need to make a box. Just use the square from tip of root to bottom of wingtip and divide by three.. Of course this is wrong and the CG would be nearer the center of the root chord.

I assure you this is correct. Used it many times. It is a way to do the math by drawing it out. Makes it simple.

@@donolson6335 So if the wing is swept the center of aerodynamic forces shifts proportionally backward so the projection on the root chord is not 33% anymore, it's more that - is that correct?

It is not correct.

It the panel is thin it will sometimes warp but most wings are thick enough that there is no wrap. I do both sides at once for elevators and rudders.

I bought the paper from U haul. It is un-printed newsprint. It is used for wrapping glass when moving. I have heard that it is also available at Walmart but I haven't looked for it there. A box from U haul cost about $11. But there is enough in it to last forever.

Some thin hairs on the surface is normal and can't really be avoided. If it is more than that I would try either a little more heat if no improvement then try less heat. The speed is limited by how fast the wire can melt the foam across the length of the wire so I would use a rate that doesn't put too much tension on the wire.

Sorry I haven't checked the comments in a long time. I use primer and spray paint from a can. Be sure to sand most of the primer off it can add weight.

Yes the router speed control will let you turn down the current. That way you can fine tune how hot the wire gets. I like this system best of all the ways I've tired.

If you go longer than 55" I would and a spar.

Yes, it is Owens Corning pink foam board insulation. I use 2" thick for my cores. It is available at most big home improvement stores.

Wall paper paste sounds like it would work well but the beauty of diluting the wood glue with water and wetting the paper is that in the end there is a small amount of glue absorbed by the paper and on the surface of the foam. This makes the covering as light as possible while still adding a lot of strength. There are a lot of other methods around that are probably a little stiffer than this method but the trade off is quite a bit more weight. The way I've shown it here is the best I've come across to be as strong and light as possible. Also remember the paper is important because the paper fibers are what add the tensile strength. If the wall paper paste is what you are used to using it will probably work best for you. The only thing I would add is to get it as thin as possible. The paper adds the most strength so the thinner the better on the adhesive.

After rolling hundreds of rocket tubes and water based glue tubes for sure the paste like when applied to wall paper gives a strength not to be compared with. Most who use this method never go back to water based as it leaves ans uneven amount of glue around. The paste is just more effecient but as you have said to each its won me I live outside the box and when i begin any endeavor I check out all the methods of doing something as in firework making I created an uproar in the field and the experts went after me for,"how dare you we have used wheat paste for centuries,",all i could do is say ,"ya know new things are always being improved on due to new chemistry. One guy it took 5 years for him to come around and say the masters were right but that was then this is now.He loved the paste and swore by it. As in construction I sure my techniques in this field will shake things up abit but thats me Mr OTB !!!!!!!!!!!!!!!!!! ps; I wasnt knocking your method just speaking to another alternative. The weight to performance might mean just installing a more powerful engine which isnt a big deal.

Thanks for the reply. I didn't take it as a knock at all. I am also always looking for new ideas and improvements. I think the paste is well worth a look. As you sound a lot like me I experiment with all types of building methods. If you want to get more techniques on building RC planes I would suggest RC Groups. It's a good form and you can pick up a lot of info on building RC planes. Thanks

I will thanks!

The paper does a lot of things. It adds a lot of strength and stiffness to the foam cores. It also protects the foam from abrasion. It makes a good surface to paint and you can use any type of paint and it will not eat the foam. Many paints sprayed directly on the foam will eat into the surface. The biggest reason is the stiffness it adds. You usually don't need a spar in a wing covered in paper where without it a foam wing will bend or break without a spar.

The paper does a lot. It provides strength and stiffness. Foam wings without the paper require a spar to be added. With the paper on the wing core is stiff enough without one. It also protects the foam from abrasion and dings. the paper also gives a good surface to pain. Many paints will eat the bear foam but with the paper on you can use any kind of paint without damaginge to wing core.

This is a brushed speed controller. They only have a positive and a negative output. The three wire speed controllers you are you mention are for brush-less motors. Brush-less speed controllers will not work for this system. Brushed speed controller are less common now because brushed motors are not as common anymore. Brushed motor controllers (ESC) can still be found at sites like hobby king and banggood etc. Just be sure you if you buy one it is for a brushed motor. Also be sure it can handle the amount of amps the power supply you are using puts out. I hope this clears up any confusion. If you have any other questions please let me know I will answer them if I can.

Yea I am not the best video producer/directer/spokesman/instructor. Hope the message gets across.

Lol, very informative nonetheless

You can use the power switch to turn on and off the unit, or you can just leave it turned on and wire up the other switch as in the video.

Thanks for the reply, do I still need to paperclip the black and green together or ignore that step?

The black and green still need to be jumped or switched. That makes the power supply turn on as it the computer was turned on.

Thank you.

Thanks. It's good to hear that the video helped out someone with the same interest in scratch building.

Bought a hanger 9 iron and a roll of thin laminating film. Works so easy and it comes out smooth and tight. This method is messy and think about it. Paper isn't going to add any strength.

Thanks