Der Big Red Max - Tape for engine retention?

[Sigmund68k]

Hey everyone,

I just started building Der Big Red Max yesterday (#9721). Other than gluing together 3 parts for the fins, it's a really straightforward build. There's just one thing that has me concerned. The engine retention in the engine mount. Apparently, the design relies on "6 to 8 layers of masking tape" to prevent an F motor from just blowing straight through the rocket?

Look in the instructions for assembly in the engine mount. There's no engine hook. No engine block. The "Prepare Engine Retention" section describes wrapping the engine with masking tape. That's...it.

Am I missing something? Has anyone launched this with success? I was planning on finishing and launching this with an F15-4 at a club launch this weekend. I'd hate to put all this effort into a glorified Party Popper.

 

[BEC]

I haven't built one of these, but I have built and flown repeatedly the Star Orbiter and the Super Big Bertha using exactly this retention method. It works just fine.

I have a roll of 1/4 inch wide masking tape I got from ASP that I use for this - just wrap a few turns around the motor at the nozzle end. Wider tape would work—wrap the tape with about 1/4 inch of the nozzle end of the motor covered, then trim off the overhang with an X-acto knife.

Composite motors (and reload cases) have thrust rings at the rear so no tape required (unless the motor is really old).

 

[MidOH]

That's what I use on the Star Orbiter and High Flyer XL.

Works fine. Reduces tail weight. I might stop using Al retainers, even with my 24/40 reloadable motor.

 

[samb]

Yes, 6 to 8 layers of masking tape will prevent an F motor from just blowing straight through the rocket. And the plastic screw on retainer included in the kit will keep the engine from leaving the aft end of the rocket when the ejection charge goes off.
Proven technology !

 

[Back_at_it]

I added a motor block to mine but the tape method works ok if you know how to do it properly

 

[James Duffy]

Absolutely, works great. As others have noted, you can install a motor block, but you will limit the variety of motors you can choose from in the future.

 

[Scott_650]

Wow - BEC’s thrust ring tape job looks neater than some of my entire builds!
Maybe I’ll stop being such a cheapskate and buy a roll of 1/4” tape just for thrust rings…

I don’t use an engine block in any of my 24mm (or bigger) powered rockets with a threaded style retainer - it’s not likely that I’ll fly a smaller, nominally LPR 24mm motored rocket on a longer APC motor or reloadable case, but I might. Doing a tape thrust ring takes literally seconds so why limit your motor choices?

 

[Sigmund68k]

Thanks for the responses everyone. I'm happy to hear all of the success stories with the tape method. I'll report back with my results soon.

This is part of my "Full Red Max Sequence" I'm planning for my next launch.
- Mini Der Red Max
- Der Red Max
- Der "Tall" Red Max (My own hybrid Mean Machine / Der Red Max.)
- Der Big Red Max
- Mega Der Red Max (Built when it was released, but never flown...)

I have a F15-4's for Der Big Red Max, and one F50-6T for the Mega Der Red Max. The built-in retention ring on the F50-6T just looks so much more sturdy.

 

[samb]

That is a nice Max lineup Sigmund ! I’m willing to bet one or two of the locals have done a tape thrust ring. Have ‘um give your big Max a once-over to ease your mind before you light the candle. Where y’all flying ?

 

[Sigmund68k]

It's with the NAR Section 473, Pittsburgh Space Command. The launch site is about 1.5 hours north of Pittsburgh, PA. I have to admit, I'm only an active member every 5 years or so. But every time I've launched with them, they've been good people.

My chances of getting this Der Big Red Max done by Sunday are dwindling. I've lost two days of painting opportunities with rain here. If I get it done, I'll definitely check with the experienced club members.

 

[Robert A Jablonski]

I have seen L motors with masking tape thrust rings. With no problems. I have flown up to Ks with it.
BTW the stock Big Max flys great on AT Econojet motors. F27R are my fave. Hey Red max with a red flame. And the AT motors have a built in ring if you still dont trust the tape idea.

 

[BEC]

I don’t use an engine block in any of my 24mm (or bigger) powered rockets with a threaded style retainer - it’s not likely that I’ll fly a smaller, nominally LPR 24mm motored rocket on a longer APC motor or reloadable case, but I might. Doing a tape thrust ring takes literally seconds so why limit your motor choices?

And since the red Estes 29mm motor adapters have a bit of a thrust ring built into them, it's also easy to fly 24mm motors in these PSII kits.

Peripherally related, I have come to love the Estes screw-on motor retainers in all three sizes and am using them in more and more builds as time goes on—even 18mm-powered builds.

 

[Scott_650]

And since the red Estes 29mm motor adapters have a bit of a thrust ring built into them, it's also easy to fly 24mm motors in these PSII kits.

Peripherally related, I have come to love the Estes screw-on motor retainers in all three sizes and am using them in more and more builds as time goes on—even 18mm-powered builds.

I fly my Super Big Bertha and Star Orbiter using the adapters frequently - SO works well on adapted BP D motors. Estes screw on retainers are an excellent value (much better than the ones I ginned up out of bottle tops) though I haven’t used any of the 18mm versions in my parts bin - yet.

 

[SharkWhisperer]

Here's precut rolls at 1/4" for convenience. Extra sticky and comes in various colors and flavors. Works well. A roll lasts awhile.

https://www.amazon.com/Masking-Spec...id=1625772869&sprefix=1/4"+ta,aps,100&sr=8-10

 

[Scott_650]

Here's precut rolls at 1/4" for convenience. Extra sticky and comes in various colors and flavors. Works well. A roll lasts awhile.

https://www.amazon.com/Masking-Spec...id=1625772869&sprefix=1/4"+ta,aps,100&sr=8-10

I might even splurge on the super sexy orange color tape - orange being a bit more “rocket-y” than blue or pink

 

[neil_w]

Thanks for the responses everyone. I'm happy to hear all of the success stories with the tape method. I'll report back with my results soon.
[...]
I have a F15-4's for Der Big Red Max, and one F50-6T for the Mega Der Red Max. The built-in retention ring on the F50-6T just looks so much more sturdy.

I think it's a natural first reaction to see the tape thrust ring and think it looks really hinky. It's a remarkably effective low-tech solution. Thank god for tape.

 

[BEC]

Here's precut rolls at 1/4" for convenience. Extra sticky and comes in various colors and flavors. Works well. A roll lasts awhile.

https://www.amazon.com/Masking-Spec...id=1625772869&sprefix=1/4"+ta,aps,100&sr=8-10

Interesting.

I've been buying this: https://www.asp-rocketry.com/ecommerce/1-4-Masking-Tape.cfm?item_id=29&parent=73&navPanel=1 for this purpose (and it's in that picture in post 2 above).

 

[Scott_650]

Interesting.

I've been buying this: https://www.asp-rocketry.com/ecommerce/1-4-Masking-Tape.cfm?item_id=29&parent=73&navPanel=1 for this purpose (and it's in that picture in post 2 above).

I can live without fancy colors and I'd rather order from one of our hobby's vendor than some faceless Amazon seller - and ASP is cheaper!

 

[MidOH]

I use aluminum tape.

 

[user 35280]

I can live without fancy colors and I'd rather order from one of our hobby's vendor than some faceless Amazon seller - and ASP is cheaper!

Am I reading that right, the blue colored 1/4” tape is $3.00 for (3) rolls? I think they charge for shipping it. I’d rather buy it from Andy@ASP as I think it’s $1.99 and it helps a Rocket vendor.

 

[boomtube-mk2]

Flavors?

Am I missing a new source of fiber here?

 

[SharkWhisperer]

Interesting.

I've been buying this: https://www.asp-rocketry.com/ecommerce/1-4-Masking-Tape.cfm?item_id=29&parent=73&navPanel=1 for this purpose (and it's in that picture in post 2 above).

Interesting? Options, Bernie, options. You retain the title of quarter-inch tape King :+}

 

[BEC]

Interesting? Options, Bernie, options. You retain the title of quarter-inch tape King :+}

Yes, interesting. I wouldn't have thought to look on Amazon for this, and I didn't know there was such a thing as blaze orange 1/4 inch masking tape until I followed your link. I thought that an interesting thing to learn.

 

[John_461]

The Estes F15 motor only produces about 5.5lbs (25.3N) of max thrust according to thrustcurve.com. A couple layers of regular yellow tape wrapped around the body of the motor will provide enough friction to keep it in place.

 

[SharkWhisperer]

Yes, interesting. I wouldn't have thought to look on Amazon for this, and I didn't know there was such a thing as blaze orange 1/4 inch masking tape until I followed your link. I thought that an interesting thing to learn.

As others have noted, I join them and am all about supporting fellow rocketeers, too.

That said, I like the colored tapes because I often wrap/color-code a bunch of 18mm motors all at once, so it makes it almost dummy-proof to grab an A motor when you want an A motor, and not mix it up with a C that'll lose your bird (yes, I've done that...). And although the benefit is questionable, the bright colors might help locate a rocket nose down in thick grass with its butt pointing at you.

Plus, you can get hot pink that our female compatriots might enjoy!

If Andy@ASP or any other fellow rocketeer would stock/sell decent colored 1/4" tape, I'd be happy to buy it from them instead of Amazon etc., even if the pricing was a little more.

 

[SharkWhisperer]

The Estes F15 motor only produces about 5.5lbs (25.3N) of max thrust according to thrustcurve.com. A couple layers of regular yellow tape wrapped around the body of the motor will provide enough friction to keep it in place.

You're right. I don't know a commercial BP motor that a tape thrust ring will not reliably work with. They also work well with my 7.5" BP motors holding 60g propellant and putting out quite a few more Newtons than Estes' motors can achieve.

 

[Donnager]

I read this thread heading as "der big red tape", and thought that was funny enough to warrant a theme rocket.

Thanks. It may take a year or two for the seed to grow roots.

 

[bjphoenix]

Yes, 6 to 8 layers of masking tape will prevent an F motor from just blowing straight through the rocket. And the plastic screw on retainer included in the kit will keep the engine from leaving the aft end of the rocket when the ejection charge goes off.
Proven technology !

This has been around for a long time and I don't recall reading about any problems with it, but it still bothered me and I never tried it. To the OP- you can take an old motor casing, wrap masking tape around it and then see how difficult it is to push the tape off. I suspect you would have to push very hard, harder than the motor can push.

 

[dpower]

I use masking tape thrust rings often, up to H motors, and they work fine, it's amazing what the shear strength of these are. Andy's 1/4" tape is perfect, and 60 yards is good for a LOT of motors!

 

[Tarantula]

.

... and the Amazon tape says it is made of Rubber.