29mm motor mount in a Estes Hi Flier XL

I am surprised that there were so few threads on this rocket, so I had to post the torture I am putting one through. This will be my first rocket to break Mach and my first to break a mile high.

Stock kit has a 24mm motor mount and is designed for Ds and Es.



I am putting a 29mm mount in it and want to stuff an I243 in it. OpenRocket puts it at just over a mile high and Mach 1.5 I think I might need to make this Dual deploy with a cable cutter.

I had a 29mm motor mount from a previous attempt at over powering an Estes Der Red Max Classic. Did not use any special building techniques and a G118BS left 2 of the fins spinning in the air at the pad. :sad: I recovered the pieces and made a nice memento.



Motor mount is nothing special but does have plywood centering rings and Kevlar tied around the mount below the top centering ring. It also has the Estes screw on motor retainer already in place.

Once the motor mount was installed I measured from the top down to the centering ring and marked the Height of the motor mount on the fin alignment marks. I then drilled small holes to create attachment rivets between the body tube and the fins the entire length of the motor mount. I don't want epoxy running inside the main body tube and making a mess.



sanded each drill spot to knock off the high spots.



The holes were poked through with a small pick to clear the dust and blown out to give the epoxy the best chance to penetrate. The entire length of the fin attachment was then sanded to increase bonding of the fin to the body, and lines redraw to align the fins.

Next up was rounding the leading edge of each fin and tapering the trailing edges. 220 grit sandpaper made quick work of that. Thin CA was then poured over the fins two times to strengthen and smooth the fins.

If I were you I would upgrade to 1/8" plywood fin for going Mach 1.5.


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Apogee has endorsed balsa for mach 1 capable 29mm minimum diameter rockets (papered though). Look up the Aspire.

I'm thinking to myself... I'd love to see this fly. Good Luck in finding it though.

I do plan on a tip to tip treatment, yet to decide on material. Lots of Tracking powder and a big Mylar streamer may help.

Wow, thats really going to giddyup quick! I'd do somthing to the fins, whether it's papering or glassing them along with possibly glassing tube, unless you dont intend on finding it it one piece, but really what do I know, I've never launched an I motor. Make sure you let us know what happens since pics of it in air will be nearly impossibe to get.

Outside my primary area of expertise, but would suspect a treatment of glass is probably in order.


Later!

--Coop

Love the hi flyer have the 4" 6.5 times upscale . Planning the 38 and 54mm min dia builds . Glassed the 26" long fins that 9.5 " tall at the widest point . Look up mega hi flyer

Chris - I am going to look that up. Sounds awesome!

Coop - I have glass, carbon and Zylon (10 times stronger than Kevlar for the weight)

CRC - Video might show a couple of frames.

Installed the fins with 5 minute epoxy tonight. I am thinking light weight glass for the tip to tip.
have to let the phone charge up so I can take a picture.

Fin Pictures

Whole thing with some of my rocket collection in the background.

I have a 4 inch coupler coming to make a Dual Deploy AV Bay.

I think I tackle tip to tip fiberglass a little differently than most.

First I mount the fin can on a piece of PVC pipe and use blue tape to secure it and cover the Motor Retainer. I also wrap the coupler with a nonstick plastic wrap to keep it from being glued in place.

I then mark and cut out a pattern for the fiberglass.

Mark out the fiberglass pieces

Then using 3M spray tack 77 adhesive I spray half the back of the fiberglass and half the body tube and one fin, align and press into the body fin junction then smooth out from there. Once one side is in place I do the other half of that fin set. I did have to trim about 2mm off the edges to get it close.

for the upper tube, I draw a line on the tube and spray half the fiberglass and half the tube with spray tack, align edge of fiberglass with drawn line and wrap around half way. spray other half of fiberglass and tube then finish wrap.

RochonRockets said:

I think I tackle tip to tip fiberglass a little differently than most.

First I mount the fin can on a piece of PVC pipe and use blue tape to secure it and cover the Motor Retainer. I also wrap the coupler with a nonstick plastic wrap to keep it from being glued in place.
View attachment 180780
I then mark and cut out a pattern for the fiberglass.
View attachment 180781
Mark out the fiberglass pieces
View attachment 180782
Then using 3M spray tack 77 adhesive I spray half the back of the fiberglass and half the body tube and one fin, align and press into the body fin junction then smooth out from there. Once one side is in place I do the other half of that fin set. I did have to trim about 2mm off the edges to get it close.
View attachment 180783 View attachment 180785 View attachment 180786
for the upper tube, I draw a line on the tube and spray half the fiberglass and half the tube with spray tack, align edge of fiberglass with drawn line and wrap around half way. spray other half of fiberglass and tube then finish wrap.
View attachment 180784

Click to expand...

what kind of fiberglass is that??

conman13 said:

what kind of fiberglass is that??

Click to expand...

Yeah??? I'm curious too.... Spray Adhesive?

Looks like thin FG matting. Have you used this method before for reinforcing?


Later!

--Coop

It is thin fiberglass matt. I like it because it does not have directionality like the woven stuff, and it is super light weight and flexible. I am not looking for a lot of strength just enough to break 1000 MPH. I use it and the heavy version to make fiberglass molds for carbon fiber parts.

The Spray adhesive is from Wal-Mart in the craft section Scotch Super 77 spray tack adhesive. It holds the fiberglass in place, allowing me to get the material tucked in all the nooks and crannies. It is repositionable for a few seconds allowing me to make adjustments to the placement. The Epoxy dissolves the spray tack so it does not interfere with the bond. I can bond all the pieces and trim excess where needed with out getting epoxy all over my tools and gloves.

Here are the pictures of the mat wet out over the entire fin can and upper tube. I added some 12K Carbon tow to make fillets and suck up the excess resin.


Tomorrow afternoon it will be cured enough to sand and start to smoothing process. The Epoxy is a very thin laminating epoxy that has a High TG ~350F and is super strong stuff. BJB enterprises TC-1620

It doesn't have to be super strong just strong enough for Mach 1.5 or so. :wink:

Went out and squeeze tested the body tubes this morning and they are MUCH stronger. I can barely deform the shape with one hand. Now for the "FUN" part of sanding it close to smooth and filling the voids.

Lookin' good.

Lots of sanding done and it is looking pretty good. Only one major void spot and one where the glass did not contact the tube.

The bad spots.

The No fiberglass spot


The one big void


I will mix up a tiny batch of epoxy tomorrow and fill in the worst of the dinks and voids along with that one spot of missing glass.

As it sits now with out the chute or motor it only weighs 7.75 ounces.

Bought the Missile works Alti-cone, Smart Sled and a RRC2 last night. Looks like it will be an exact replacement for the cone on this bird and will make dual deploy so much easier.

Got the Alti-cone in the mail today. Figured I would give an update on the sand and fill process.
Unboxing the Alti-cone
3 bags in the mailer pouch. 38mm Alti-cone, 29mm S.M.A.R.T sled and the RRC2

Unbagged the Alti-cone, disassembled it and in inserted the sled.

Reassemble

Try it on for size

Comparison of the Alti-cone and the original Estes Nose cone from the kit.

The nose cone felt VERY rough and I was concerned about how much work it was going to be to get it smoothed out. I called MissileWorks and they were very helpful. I decided to wipe it down with Acetone to clean residue off and prime it to prepare for sanding it smooth. The Acetone melted the surface just enough to knock off the worst of the roughness.
Alti-cone before sanding

Here is a shot of the body in primer. Still had to touch up a couple of tiny spots but it is close to ready.

This makes me want to build the 38 and 54mm MD hi flyers and build another 4" but this time think 75mm hole this time and adapt down to 54

Lots has been done. The Alti-cone is all done and the main body color is done, just have to wait for the paint to cure enough to tape off the fins to spray them.

First the Alti-cone, sanded the first coat of primer off and shot a second coat of grey primer.

Sand & repeat

Now some silver and the Final blue coat.


Back to the body.

The Alti-cone has a smaller shoulder diameter than the inside of BT60, but it fits perfectly in a BT60 Coupler. A good smear of 5 min epoxy on the outside of the coupler and again on the inside of the upper part of the body tube, then insert coupler and wipe off excess epoxy.

Last coat of Primer

A coat of Gloss white to make the Orange POP.

2 coats of Orange


I will give it a day or 2 to cure up before taping it off to paint the fins. Any guesses on fin color??

Lookin' Good!

Put the chute in and test fit the 6 grain case. It all fits!

Without the motor it comes in at 397 grams or 13 7/8 ounces. 3+ calipers of stability with out motor, 1.2 calipers with the I205 loaded.

First flight will be with the Aerotech single use I205 at Orangeburg, SC over Laborday weekend. Sims out to Mach 1.2 and just under 7000 ft. Using the RRC2 to pop the nose at apogee and fire a cable cutter at 500 ft. Might put the Jolly Logic Altimeter 2 in there to record the speed a height if I am feeling brave. Will post boost video after.

Paint and Stickers are done. Just waiting 24 hours to do the clear coat.

That came out Awesome!!!:clap:
Best of Luck on your first Flight.

Just wanting a double check on my math for the BP charge. The space left in the rocket is about 9 inches by the 1.5 inch diameter. The Chute takes up about 2.5 inches. I have a fairly loose fit on the nose cone and 2 #2 shear pins. To get the ~60PSI I need to cut the shear pins and eject the nose I calculate .35 grams of 4F BP will do it. I will ground test but want a second opinion to see if I am close to the right charge size.

She did not survive her first flight.:cry:

I bumped the BP charge up to .5 grams but did not ground test. I just could not figure out how to ignite the charge inside the tube with the tools I have. The shear pins did not shear and she came in ballistic, far from the flight line and I only found it by sheer luck. Had to go back a get a shovel to get the altimeter and the tip of the nose cone out of the ground.



She really did scream up to amazing heights. I will build something better next time and not use shear pins again until I can figure out how to ground test.

OUCH!!! Sorry to hear about your loss...

Perhaps next time, you might want to try tape instead of shear pins? I remember reading where Mike Fisher (Binder Designs) used it on some of his HPR builds, and things went well for him.

Pointy Side Up!
Jim

Shear Pins, on a tiny Rocket like that?