2 Meter EPP Swift S-1

[Wayne]

We received some new planes in from Causemann and going to try and get this one built in time for Sunset. Not much free time, so don't know if it will make it or not.

These kits are pretty neat, basically CNC milled EPP, so you don't have to do a ton of sanding. Just clean up the fuzz a bit.These kits are just the foam, and no instructions. So this will serve as instructions for future builds.

Got a start on it last night. Here are the parts included, not shown are the EPP wing panels. (We will probably offer a deluxe version with all the carbon and such in the future.)

First step is to clean up the tail joint for a nice clean fit. I used a little sanding block. Does not need much sanding.

Then we can glue the front and rear together. II'm using Foam Cure, but you could use just about decent glue here. Some pins to hold it nice ans tight while the glue cures.

Probably don't need the weights, but I had them handy. We can also glue the canopy together.

 

[Wayne]

A bit about this current kit.

First off, I love this thing, please keep this in mind. With this said I will be making a number of changes to the kit for my build. Here is a video of a stock version flying with some added lead:

I do like the fuselage and size of this model. I personally do not care for the wing airfoil or the planform and will be making a new wing and it will use a balsa trailing edge and will add flaps.

Since a one piece 2 meter glider would be a major pain in the butt to transport I will be making the wing removable. This may be a bolt on wing, or I if I am adventurous I could make the wings 2 piece with a wing joiner. Due to time constraints I will probably go with the bolt on option as it is a quicker process.

I also plan to replace the EPP tail with Balsa tail. A buddy has a DAW KA that has been around for many years and it has a 1/4" balsa tail. I'm sold on that. I'll be adding a ton of carbon to the wing and fuselage as I am wanting to greatly increase the AUW for our California slopes.

I'm going to see if I can incorporate a ballast tube into the fuselage.

Those are my current thoughts.

 

[Wayne]

On with the build!
I started off with double checking that the tail is parallel to the wing, this is what I like on my slope ships. I just used the carbon strip I'll be using to stiffen this fuselage in the vertical axis. Yep, looks good.

The plan is to use the beefy 0.8mm X 25.4mm x 1000mm Carbon Strip to stiffen the fuselage in the vertical axis as I like the vertical axis to be very strong. And I'll use a 1mm X 3mm x 1000mm Carbo Strip for the horizontal axis as I do not mind a little waggle on this axis (rudder) and the tail gets rather thin on this Fox Swift. These will be carved into and glued inside the foam. Here is where I'll be placing the 25.4, and I have carved it down to fit and rounded the corners:

I marked out the outline with a pen and then worked out placement for the rest of the items that will be getting buried. (I should have marked the battery location at this time as I ended up forgetting to cut out my pocket for it! Don't build when you are tired. Anyhow, here are the pushrods, battery and smaller carbon placements.

Time to start carving. I put some masking tape on the outer edge of my cut and set up the rotary tool to remove just enough material to to make the carbon strip flush with the foam. And carved it out.

Then marked out where the elevator pushrod would go and carved that out freestyle with the rotary tool.

Then did the same basic operations on the other fuselage side. You can see how all of these will end up being glued in contact with one another.

Not the gentle arch of the smaller carbon strip, I wanted it up close to the tail group for strength and up into the nose area. I hold the arch with some push pins some I can mark it with a pen.

Now it is easy to carve with a rotary tool:

 

[Wayne]

Here is a test fit of everything. I wanted everything flush so the glue is not stressed and I would not have any open joints.

Time to glue - I used a slower curing foam glue and lots of tape. Basically glue in the pushrods, then glue in the carbon, then glue both sides together. Think this was about a a small bottle of glue. LOL

And then let it cure.

(I'm writing this a couple of days later and she is perfect! Stiff and strong!)

 

[Haoyang Wang]

Time to glue - I used a slower curing foam glue and lots of tape. Basically glue in the pushrods, then glue in the carbon, then glue both sides together. Think this was about a a small bottle of glue. LOL

Wow, clean and neat!

What foam glue did you use to glue the 2 halves?

For me, often the cut-open EPP cells would be soaked in the glue and swell up at the seam (at least temporarily). Maybe I had applied the glue too thick at places? For my current build, I am thinking about using 3M 77 spray glue.

 

[thenated0g]

My goto for epp is either expanding Gorilla glue (brown or white) or e6000, shoogoo, welders, etc.
Hot glue also works really well and is fast setting so ill use that when i am in a hurry.

 

[Wayne]

We tend to use Foam Cure a lot at the shop:

Foam-Cure 4oz

Foam-Cure 4oz

alofthobbies.com

It is easy to work with and works well.

I also like E6000 and Foam Tac a lot, but the Foam Cure was out on the table, so I grabbed it.

3M Super 77 works well for some things, but I need the carbon firmly glued into the fuselage, not sure Super 77 would have worked well here. I also wanted some work time to get things correctly aligned.

Nate - Is my new wing ready yet. LOL

 

[thenated0g]

Read your PM's!

 

[Haoyang Wang]

I usually use E6000 and Goop. Gorilla glue to fill up the cavities.

Closing the 2 halves is a complicated operation which needs extra work time. While I was trying to align the 2 halves, I would find the foam swelling up at the edges. The swell will mostly subside as the glue cures, but in the meantime it makes the alignment and taping up difficult. Maybe I should apply less glue in the areas close to the edge.

 

[Wayne]

I set the glue about 3mm from the edge. I keep a paper towel handy and wipe off any the comes out.

After tapping I left it over night. It did make some glue bubbles on the bottom. The bad news is this glue had passed through some of the ink I had marked on the inside so I have some ugly seam line, but it is on the bottom so no big deal.

Question for you all. I'm not sure what I want to cover the fuselage in. I'm thinking goop. I did this many years ago on my Slope Monkey and it has been a great result. As I recall on that one you tape the fuselage and then iron the tape smooth, then goop it several times with thinned goop. I think this will look better and last longer than any iron on covering.

Thoughts? is there something else you would suggest? I expect this plane to last 10 years before it needs a rebuild. (if no massive crash occurs)

 

[Wayne]

Nate is it done now?? I's been 5 minutes already.

 

[Hawaii Sloper]

We received some new planes in from Causemann and going to try and get this one built in time for Sunset. Not much free time, so don't know if it will make it or not.

These kits are pretty neat, basically CNC milled EPP, so you don't have to do a ton of sanding. Just clean up the fuzz a bit.These kits are just the foam, and no instructions. So this will serve as instructions for future builds.

Got a start on it last night. Here are the parts included, not shown are the EPP wing panels. (We will probably offer a deluxe version with all the carbon and such in the future.)
View attachment 14905
First step is to clean up the tail joint for a nice clean fit. I used a little sanding block. Does not need much sanding.
View attachment 14906

Then we can glue the front and rear together. II'm using Foam Cure, but you could use just about decent glue here. Some pins to hold it nice ans tight while the glue cures.
View attachment 14902

Probably don't need the weights, but I had them handy. We can also glue the canopy together.
View attachment 14904

View attachment 14903

Hey @Wayne are you gonna have any of these kits available for/at Sunset?

 

[Wayne]

We have one more in stock, I have asked Nate to cut an extra set of wings for you.

We also have a 1.2 meter version. They just arrived yesterday.

 

[Hawaii Sloper]

We have one more in stock, I have asked Nate to cut an extra set of wings for you.

We also have a 1.2 meter version. They just arrived yesterday.

Thanks!

 

[Hill Hobbit]

Er, that’s a Swift, not a Fox. The Fox is very similar but the fin and rudder are swept back…

 

[thenated0g]

Heres another fox without the swept back:

Causemann's FOX EPP 120cm span glider - RC Groups

Mini-Review Causemann's FOX EPP 120cm span glider Slope Soaring

www.rcgroups.com

 

[Wayne]

Yeah, I'd say it is a Swift also. Either that or it is a very poor scale job on the Fox.

I have been building this and thinking it was a Swift S-1 but never bothered to compare - Yep, for sure is a Swift, but they sell them as Fox. LOL I'm going to update the title of this thread.

All fixed LOL.

 

[thenated0g]

Cut out my first wing core this morning out of EPP in prep for doing those Fox wings. As seen below in the video, this outer core of a Starfire plank with not much sweep came out perfect. When I tried doing the next piece next to it, which actually has quite a lot of sweep, it's about a 30° angle I found that I had a much larger kerf on the wingtip side so the parts actually didn't match up. So I made up some new cutting files adjusting for the different kerf and I'll try cutting that piece out again. But pretty happy with how EPP cuts.

 

[Wayne]

That looks really good! Impressed with that trailing edge too! Thought the bigger sweep might give you some issues. I have seen other EPP cores with a lot of sweep have issues, usually one end of the cores looks and feels great, and the slow side of the cut is rather crusty. A little sanding sorts it out.

Thought I'd share what Nate will be cutting for this plane. The spar placement is my shade tree designing. Here is the overall planform. The wing will be 4 different panels as Nate can not cut a 1 meter panel, so I thought I could use this to my advantage.

Planform:

Here is the inner panel, what we have here is 5 carbon spars and a wire channel between the front and rear spars for the flaps and ailerons. The front spar (built from 4 pieces of carbon strips) goes from tip to tip for the completed wing. Yes, this will be a one piece 2 meter wing. While the strips may look tiny, they nearly touch out at the wing tips. At the center of the wing I will be removing the foam between the spars and adding a carbon joiner that glues to the 4 spars making them a single structure. Should be light and strong. As I recall we are using 1mmx3mm and 1mmx6mm strips.

Here is the outer panel, no wire channel as the aileron servo will be in the other panel. And no rear spar. Don't think we will need it.

A look from the wing tip:

 

[thenated0g]

devwing foam 2 has kerf compensation settings you can enter for the root and tip side. On insulation foam, cutting twice the speed, the kerf was not that bad on the wingtip. Going to EPP and dropping to half the speed it is sitting longer on the shorter wingtip side so i guess it makes sense that the kerf would be bigger. This is also why i like to cut out 2x one inch pieces of foam and place them where the 2 roots are (each end of the wing) and than you get real world results of what the wing will look like without wasting half a meter of foam.