Build thread: NewWay Angled Invader

[neil_w]

I don't build a lot of kits, but I've been wanting to try a NewWay kit for a while. When I saw that the Angled Invader was introduced recently, I knew that was going to be the one. As with all my builds this will be leisurely but hopefully interesting.

This is of course a NewWay-ified version of the Estes Alien Invader, a classic Wayne Kellner design. The original is all curves, somehow it translates beautifully to angles (there is not a curve to be found in this kit other than the motor tube.)

When I first opened the package to look at the parts, I was frankly blown away. Look:

The quality here is a amazing. Rick at NewWay (aka @Bluegrass Rocket) clearly has put a lot of work into this, and evidently has a good working relationship with his bag sealer. Look at the form-fitted bag with the nose cone and pod tubes!

There's one sheet of laser-cut balsa, a whole sheet of cardstock jigs, and all the other usual stuff, neatly divided into small bags. The nose cone is 3D-printed, we'll get into that some more. Oh, and a little bag with sandpaper and some nice wood Q-tips. The instructions are comprehensive, well illustrated, and look great.

This should be fun.

 

[Bluegrass Rocket]

Thanks Neil for getting and building a kit. Hopefully it goes well and you enjoy it.

Rick
NewWay

 

[Back_at_it]

Picked up one of these when I was at ERockets a month ago. Looking forward to building it.

 

[BABAR]

Cool. Hard to tell from cover pic, are the outboard motor pods closed or open and painted red on inside?

 

[neil_w]

They're open and painted orange.

 

[neil_w]

PREP, PART 1

Before starting to build I always think through what my finishing strategy and sequence will be. CWF? Label paper? Will there be filler/primer, and if so before or after assembly? I confess this model had me a bit stumped (you'd think by now I'd have this all figured out). Filler/primer post-assembly seemed impossible due to the very fiddly wing assemblies, and papering the wings also seemed impractical. I also didn't think I really wanted to filler/primer all the fins individually.

After thinking about it way too long, I decided to just get started by CWFing everything, and would figure out the rest later. I thought I'd be clever and do the whole balsa sheet at once, to save me from needing to separately handle all the very small pieces. I applied a layer to the whole sheet using a chopstick:

The square body tubes are interesting. They're fairly thick-walled, necessary because they don't have the natural strength of a round tube. Also, on the outside of the tube, the consecutive wraps of paper overlap a bit, so instead of indented seams, you get spiral bumps about 1/8" wide (maybe a bit less). Normal seam filling strategy wouldn't work here; fortunately I don't use normal seam-filling strategy. Instead, I did my usual and slathered CWF over the entire tube. After sanding, there was still some evidence of the bumps in some places, but I wasn't going to pile on tons more CWF to get rid of them. We'll see how it all looks in the end.

Here is everything after being sanded down.

Those little guys in the upper left are the (square, natch) dual launch lugs, which were quite bumpy to start, and definitely benefited from a good layer of CWF.

While I was at it, I had a look at the nose cone. It comes as three pieces: the central nose, plus the two "bumps" that go on either side. All were cleanly 3D-printed in ABS.


The nose cone came mostly pre-sanded, which is very cool. I'm guessing that with its flat sides it is easy enough to whiz a sander over it. The little bump pieces still needed sanding, which turned out to be quick and easy. The ABS seems to sand much more easily than the PLA I've used before (which is like sanding concrete).

 

[Back_at_it]

Looking good. I like the idea of doing the the filler on the sheet. Any issues with warping?

 

[neil_w]

No warping, but other problems (some obvious in hindsight). I do not recommend this method. Will provide further details soon.

 

[Back_at_it]

No warping, but other problems (some obvious in hindsight). I do not recommend this method. Will provide further details soon.

Little hard getting them apart afterward?

 

[neil_w]

That's one problem.

 

[BABAR]

No warping, but other problems (some obvious in hindsight). I do not recommend this method. Will provide further details soon.

I had this presumably brilliant idea before and tried it. I had a hard time finding the original cut marks after doing this.

 

[neil_w]

For some reason I was holding off on discussing this but now that it's in discussion I might as well give my thoughts. There are two primary problems I had with the full-sheet CWF approach:

1. What started as a sheet with a bunch of cutouts becomes one solid sheet. You can't see the cut lines clearly, and you can't feel them either. I was eventually able to separate everything by snapping off little pieces at a time; the CWF was sufficiently weaker than the solid balsa that it broke pretty reliably on the cut lines. But it was slow going and did not feel good. Afterwards, while cleaning up the pieces, I notice in a few places some bits of wood that were still stuck to the fin pieces, and then had to snap those off. The whole process was just icky and uncomfortable and a bit nerve-wracking.

2. The CWF makes a mess of (some of) the fin edges. When slathering the sheet, quite a bit of CWF gets pressed into the seams and adheres to the fin edges. There are two problems there:

a) The CWF is not distributed evenly on each edge. There are big globs here and then nothing there. That make sanding it smooth a pain, especially on oddly-shaped pieces where you can just run the whole edge on a sanding block.

b) Some CWF inevitably ends up on fin roots, where we do not want it. Sanding the uneven CWF off the fin roots with fin tabs was very difficult (impossible?) to do without at least slightly changing the shape of the fin root, which then makes fit on the body worse, which *then* requires a lot of fiddly sanding to restore proper fit, although it'll never be perfect again. Even worse, it got into the locations where the two pieces of the main wings fit together, puzzle-like. There was absolutely no way to achieve perfect fit there after sanding out the CWF.

This might have all been OK with simple trapezoidal fins or something, but with the complex shapes in this kit it was just not good. I did eventually get everything into proper shape, but I will probably not ever do it this way again.

 

[BABAR]

I assume you are not satisfied with simple papering because grain shows through? might Be a hefty weight penalty, but would TWO layers of paper be sufficient to obscure the grain lines, and give even stronger fins? I am thinking glue technique, not self-adhesive, although that could also be tried.

could even do self adhesive over glued paper. The first provides strength and covers most of the grain lines, the second adhesive layer is easier, covers the rest of the grain lines, and covers any drips or other defects from the papering process, and gives you a clean surface to coat.

i worked with the New Way tubes, at least the original ones. They had a nice cool factor, they were a bit heavier than the standard round tubes, not just due to the shape. Easily accounted for by going up a motor size.

 

[neil_w]

I assume you are not satisfied with simple papering because grain shows through?

Don't assume. I use label paper, which does not show grain.

In this case there were (a) some very small pieces that would be hard to paper, and (b) the shape of the assembled wings would be very challenging. More about this soon.

 

[BABAR]

Don't assume. I use label paper, which does not show grain.

In this case there were (a) some very small pieces that would be hard to paper, and (b) the shape of the assembled wings would be very challenging. More about this soon.

What makes you choose CWF over papering in different cases?

 

[neil_w]

What makes you choose CWF over papering in different cases?

Nowadays I choose papering the vast majority of the time.

 

[neil_w]

FIN PREP, PART 2

Well, since it has become a discussion topic, might as well finish up on this. Please note that these posts are not in the exact order I did the work, nor in the order of the instructions.

After breaking apart the balsa sheet, I commenced sanding the heck out of everything to clean it up. While working on the ventral/dorsal fins, I discovered "the hard way" that the grain direction made for very delicate pieces, particularly the front points... they'd be fine once mounted on the rocket, but until then would require very careful handling. Well, after gluing one of the fins back together (all three pieces ) that I would paper these so I didn't have to worry about it. And so I did.

At this point I was thinking that I would do filler/primer on the tubes, nose cone and the large fins prior to assembly.

Assembling the wings was next, and I got to use the first of the many, many jigs included in the kit.
Top left is the jig for wing assembly. Extremely simple and effective:


At this point I decided that sanding the filler/primer on those was going to be another delicate handling affair, and so I decided to paper those as well. First label paper was applied to both sides, leaving the root edges clear:


First the outer edges were sanded off, easy enough. I left the fin edges square (I'm not about to start introducing curves to this kit) which made it easier.

And then the inner parts, which were fairly challenging. But it didn't really take that long, and results were good.

Have I mentioned recently how much I love my sanding sticks?

CA was applied to the edges and now all fins were finished.

I could easily paper the rest and I still might, but probably not. In hindsight, I would have just papered everything and passed on the CWF. Would have been much less work. At some point along the way I also decided not to apply filler/primer to the wings. I haven't decided yet about some of the other fins.

This was a lot of prep. Time to get to building.

Oh, one final note: the balsa is very good quality, seems to be right in the perfect medium-density range. Very nice to work with.

 

[neil_w]

MOTOR MOUNT

The motor mount is a fairly routine affair, other than the use of "centering squares" rather than rings. The squareness permeates the entire build in interesting and sometimes unexpected ways, and it's part of what makes this kit (and, presumably, other NewWay kits) a fun change of pace.

Shock cord mounting is via a standard kelvar-behind-front-centering-square arrangement. A piece of heat-shrink about 4" long is provided to protect the Kevlar closest to the mount. This is a good idea and I wonder why I've never done it before (I have seen it discussed on the forum in the past). Anything to prolong the life of the Kevlar (short of a replaceable scheme) would seem to be a good thing.

Then I realized that I didn't actually have anything with which to shrink the tubing (apparently I haven't used any heat-shrink in a long time. how is that even possible?). So I brought the half-built mount to work, where there would surely be a heat gun... heck, I purchased one there myself in the distant past, but no idea where that one ended up. Well it turns out there were no heat guns on premises, but there was this bad boy:

This is a hot air station used for PCB rework. Let me tell you, using this thing for heat-shrinking was the most oddly satisfying thing I've done in a long time. I enjoyed it so much I actually thought briefly about purchasing a small one for home for just this purpose... and then promptly realized that was idiotic, and dropped the idea. I will probably pick up a cheap heat gun, though, it's a good thing to have around.

The finished mount was installed into the end of the body tube without any drama.

Not even a thought of upping the mount to 24mm on this build.

 

[BABAR]

MOTOR MOUNT

The motor mount is a fairly routine affair, other than the use of "centering squares" rather than rings. The squareness permeates the entire build in interesting and sometimes unexpected ways, and it's part of what makes this kit (and, presumably, other NewWay kits) a fun change of pace.

Shock cord mounting is via a standard kelvar-behind-front-centering-square arrangement. A piece of heat-shrink about 4" long is provided to protect the Kevlar closest to the mount. This is a good idea and I wonder why I've never done it before (I have seen it discussed on the forum in the past). Anything to prolong the life of the Kevlar (short of a replaceable scheme) would seem to be a good thing.

Then I realized that I didn't actually have anything with which to shrink the tubing (apparently I haven't used any heat-shrink in a long time. how is that even possible?). So I brought the half-built mount to work, where there would surely be a heat gun... heck, I purchased one there myself in the distant past, but no idea where that one ended up. Well it turns out there were no heat guns on premises, but there was this bad boy:
View attachment 542009
This is a hot air station used for PCB rework. Let me tell you, using this thing for heat-shrinking was the most oddly satisfying thing I've done in a long time. I enjoyed it so much I actually thought briefly about purchasing a small one for home for just this purpose... and then promptly realized that was idiotic, and dropped the idea. I will probably pick up a cheap heat gun, though, it's a good thing to have around.

The finished mount was installed into the end of the body tube without any drama.
View attachment 542010
Not even a thought of upping the mount to 24mm on this build.

Just a thought from someone who hasn’t used heat shrink tubing. If you didn’t shrink it but used non-CA glue to hold it in place, wouldn’t it function just as well and weight just as much? The ejection charges might “self-shrink” it anyway.

Also, I would think with the space between the round motor mount and the body wall there would be plenty of space for @hcmbanjo ‘s Q-Tip removable/inspectable/replaceable shock cord system.

 

[lakeroadster]

Just a thought from someone who hasn’t used heat shrink tubing. If you didn’t shrink it but used non-CA glue to hold it in place, wouldn’t it function just as well and weight just as much? The ejection charges might “self-shrink” it anyway.

Also, I would think with the space between the round motor mount and the body wall there would be plenty of space for @hcmbanjo ‘s Q-Tip removable/inspectable/replaceable shock cord system.

PDF & Diagram for folks that aren't familiar...

 

[neil_w]

Just a thought from someone who hasn’t used heat shrink tubing. If you didn’t shrink it but used non-CA glue to hold it in place, wouldn’t it function just as well and weight just as much? The ejection charges might “self-shrink” it anyway.

Also, I would think with the space between the round motor mount and the body wall there would be plenty of space for @hcmbanjo ‘s Q-Tip removable/inspectable/replaceable shock cord system.

If you're not going to shrink it then there's no point in using heat shrink. Gluing a piece of heat shrink onto the Kevlar would be a messy and pointless job IMHO.

As for the replaceable Kevlar mount: it could certainly seem to be possible here, but I didn't feel like taking any chances hacking up the centering squares. Besides, I rarely get enough flights on one rocket to need Kevlar replacement (the next time I need it will be my first).

 

[lakeroadster]

If you're not going to shrink it then there's no point in using heat shrink.

This comment confuses me? Heat shrink tubing is used to protect the Kevlar from the ejection blast. That protection, one would think, would be even better if there was an air gap between the tubing and the Kevlar.

6 of one, half a dozen of the other.

I'd kind of like to see one installed un-shrunk.... just to see if the ejection blast heat shrinks it.

 

[neil_w]

This comment confuses me? Heat shrink tubing is used to protect the Kevlar from the ejection blast. That protection, one would think, would be even better if there was an air gap between the tubing and the Kevlar.

The idea of using heat shrink without shrinking it confuses me... so we're even.

 

[BABAR]

.

Not even a thought of upping the mount to 24mm on this build.

I bought some of Randy’s old tubes when they first came out. They were a bit on the heavy side. And my designs can be draggy. I wish I had upped to 24 mm. Then again, this was before the Quest 18 mm Ds came and the Estes C5 was re-released.

 

[neil_w]

This rocket is 2.4 oz, quite a bit below the threshold where I would normally consider upping the mount. Also then I'd need to fabricate brand new centering squares. I expect satisfying flights on a C6.

 

[BABAR]

Package card and erockets lists weight as 2.4 oz. Maybe that is without motor. C6-5 motor lists as 0.91oz

https://estesrockets.com/wp-content/uploads/Educator/Estes_Engine_Chart.pdf
https://www.erockets.biz/newway-flying-model-rocket-kit-angle-invader-nwy-46/
I will be curious to see if it comes out under 4 oz (upper limit for B6-4 and C6-5) ready to fly on the pad weight.

Then again, it has a lot of fin area, so that may help stability.

I gratefully expect that like all your builds you will post a weight when complete.

 

[neil_w]

Package card and erockets lists weight as 2.4 oz. Maybe that is without motor. C6-5 motor lists as 0.91oz

Of course that is without motor, the only way a manufacturer can possibly specify the weight of a rocket.

Some 18mm rockets from Estes:

• Interceptor: 3.9 oz
• Low Boom SST: 3.8 oz
• Antar: 3.7 oz
• LEO Space Train: 3.4 oz
• Centuri: 3.1 oz
• Big Bertha: 2.5 oz
• Der Red Max: 2.4 oz

I for one do not plan on spending one millisecond worrying about whether this 2.4 oz rocket is too heavy for an 18mm motor, regardless of their stated max lift off weight for the C6.

 

[neil_w]

FINISHING UP THE WINGS

A nifty little jig is provided to position the little... "I don't know what to call them" pieces that go on the wings. I dribbled a little medium CA on the seams to glue it together. First time I've used CA to actually, you know, "glue stuff" in a while (vs. just hardening). Here it is drying:

Then I realized I was missing another little piece that goes on the tab shown at left; I added that after.

With the jig pushed into place on the wing, the little pieces fit into position:

Like I said, nifty.

The four pieces were glued in, and very small TBII fillets were applied with a toothpick, just to seal the joint.

These pieces are not structural and are pretty well protected from harm (e.g. landing impact) so I was not too concerned about strength. So gluing them to the surface of the label paper was fine. When finished they felt very solid.

 

[Pappy]

...without motor, the only way a manufacturer can possibly specify the weight of a rocket.
...stated max lift off weight...

just out of curiosity, how much weight do you think is added to the roc with all the finishing; glue, sealer, primer, et al?

 

[neil_w]

just out of curiosity, how much weight do you think is added to the roc with all the finishing; glue, sealer, primer, et al?

It varies. I'll weigh the rocket when I'm done and we'll see.