Nytrunner
Pop lugs, not drugs
That's a question for Estes and the paper co. It'll all come down to how much it'll cost to implement, and how much a price increase the market will bear.
Anyone still having E engines explode
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That's a question for Estes and the paper co. It'll all come down to how much it'll cost to implement, and how much a price increase the market will bear.
shreadvector
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Estes’ new motor making machine must be working. All the D12 and E12 motors at my local Hobby Lobby all have date codes from late 2020. And the D12 date code is printed in a way different font.
I did not buy any because we are in lockdown and there are no legal launch sites.
I did not buy any because we are in lockdown and there are no legal launch sites.
Fred, you should have buy a few packs anyway... your not thinking correctly in a lockdown in your Commie state .. You buy them and stash them like the wipe paper , Hi HI
In the Covid economy, with periodic random shortages, you get more of what you normally use, even if you are aren't in need right now, when you find it, just in case. Kind of like the old Soviet Union, where you'd wait in line for hours to get an item, and if you were lucky enough to find one, you got it and either traded with your fellow citizens or put it on the black market. Didn't matter if you needed it or not, you were glad to get it. 
You mean like Toilet Paper right? LOLIn the Covid economy, with periodic random shortages, you get more of what you normally use, even if you are aren't in need right now, when you find it, just in case. Kind of like the old Soviet Union, where you'd wait in line for hours to get an item, and if you were lucky enough to find one, you got it and either traded with your fellow citizens or put it on the black market. Didn't matter if you needed it or not, you were glad to get it.
Repackaging those rolls into 20-sheet packs for eBay just turned-out to be too much work.
Yep.
I was decently stocked on TP back in Feb (what I thought was enough), and once the Great TP shortage of 2020 arrived, I didn't see TP in the stores around here for 5 (!) months. I was down to 3 weeks left on TP, and not much better on paper towels.
shockie
High Plains Rocketeer
OK folks I either had a brain aneurism or a brilliant idea, I can't tell which....
How about if Estes was to combine their plastic motor retention rings with their plastic engine adapters........ and it's made out of CFRP .....that's carbon fiber reinforced polymer which is sort of the type of plastic that ATQ makes their motors from..... you take a regular Estes BP motor, insert it into this outer plastic casing and screw in the bottom ring which is designed to also hold the clay nozzle in place. The BP motor can now be run at 2 to 3x chamber pressures increasing the Isp by maybe 15% . You would only need this outer exoskeleton casing for D48 E50 and F40 BP motors...... It wouldn't add much weight, and they are reusable. They could be sold along side the actual motors in the same package .
It's a reloadable BP motor in a plastic casing......
How about if Estes was to combine their plastic motor retention rings with their plastic engine adapters........ and it's made out of CFRP .....that's carbon fiber reinforced polymer which is sort of the type of plastic that ATQ makes their motors from..... you take a regular Estes BP motor, insert it into this outer plastic casing and screw in the bottom ring which is designed to also hold the clay nozzle in place. The BP motor can now be run at 2 to 3x chamber pressures increasing the Isp by maybe 15% . You would only need this outer exoskeleton casing for D48 E50 and F40 BP motors...... It wouldn't add much weight, and they are reusable. They could be sold along side the actual motors in the same package .
It's a reloadable BP motor in a plastic casing......
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... and how much more $$ would you be willing to pay for that?
BP motors have relatively low ISP (about 1/3 of APCP).
Tweaking BP's ISP by 15%, even if achievable, is a marginal improvement compared to transitioning to APCP motors.
https://www.rocketryforum.com/threa...-build-their-own-engines.163771/#post-2085636
shockie
High Plains Rocketeer
Its not only the marginal Isp improvement, it woukd also open the door for deeper cores resulting in high thrust BP motors. Plus it prevents the clay nozzle from blowing out.plus you could even use apcp delay trains with the bp motor core...it opens up all kind of possibilities with bp motors that you don't currently have.
These cases could have replaceable nozzles and real nozzles to improve their performance..
Don't be an apcp snob. Comparing bp to apcp motors is like comparing apples to oranges. There's a place in this world for both of them.
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We actually tried something like that once, and I think it may have been Scott Pearce’s idea. We put an Estes D motor inside a reloadable casing and fired it with a smaller nozzle. It worked, and the Isp was indeed increased. Not sure it was enough to compensate for the extra weight, though.
shockie
High Plains Rocketeer
Since DEF already have a pretty thick paper casing, the outer exoskeleton plastic casing wouldn't have to be as thick as they normally are for composite motors so that would help in the weight department. You could even probably get away with using a thinner paper casing for even more weight savings. The addition of a real formed nozzle should also improve the combustion process and make it much more efficient. Perhaps the increase in Isp would be more than enough to offset the slight increase in weight...... The exoskeleton itself would be re-useable and you would just have to buy nozzles like we do now with RMS kits. In addition, Estes could get rid of their delay trains and just buy and use delay train material from ATQ. This would open up the prospect of a master delay train that could be adjusted as they are today. Plus since you don't have to worry about engine nozzle blowups because of the increased operating pressures that open up Estes to design higher thrust motors which hobbyists would like. And with higher thrust motors the increased weight of the casing wouldn't really matter. I think there's a lot more pluses to this idea than minuses.
It would allow Estes to create a hybrid BP reloadable motor system that would be even safer than todays. It could reduce wear and tear on the Mabels as you don't have to make clay nozzles; you can create formed combustion cores of various sizes; it overcomes the technological bottleneck with mechanical bonds; it opens up the door for more motor types. As far as deeper cores goes......you cannot tell me that in this day and age that an automated machine can't be made to core BP motors safely, if you don't want to use spindles/pintles/drifts or whatever you want to call them. Imagine a coke bottling line. ever seen one. notice how the bottles go in a line.....what if you had a rotating table that had drills instead of hydraulic rams..... it could be so designed that if a blast occurred in the drilling of 1 motor, the small blast wouldn't travel to the rest of the motors.... yes this machine would cost some money to design and create, but just think how this machine would open up new motor possibilities
I am launching from the back yard. Heavy and just enough power to get 400' And I am happy. Although my last flight of my Cherokee D (Scratch build) went out of sight and it is slightly upscaled. D powered and no issues. I did have a E cato last year on old engines.
LG~
Sounds cool but I am just going to use Aerotech 18/20 and 24/40 reloads, they seem to work very well. The only issue is sometimes they do not like to ignite.
EK~
Latest "E" motor CATO from yesterday. Nov. 6
I’m feeling like I being left out of all the fun. I keep flying my stash of E9 and E12 motors and have yet to have one Cato. I just looked at the flight logs and I’ve flown 96 E9 and 47 E12 motors.
The rocket gods are smiling down on you.
Bill Stine mentioned that Mabel now has "more drops and more presses" that create a "better grain." The Estes modification to Mabel takes more time to produce each motor however the modification and re-tooling in the production of E-12, F-15, and E-16 black powder motors should improve reliability. Look for 2021 date codes on black powder. Bill's comment comes at 1:00 (one minute) into this interview: video
Here is yesterdays video of my SLS exploding. E-12-6 made in 2019
No I'm getting Good ones from Hobby Lobby and don't hesitate to use them before they get pissed off. Had some bad ones last year but they were old. Messed up my LOC Graduator (BTW is now being retired after almost 20 years. Spent 4 weeks in a tree and it rained a lot in PA. RIP).
I didn't see this at the beginning of the year. Improved E9 and E12 motors is good new. Looking back, though...
I've never had a rocket damaged in a CATO. I've had four engines go BANG and spit their nozzles with no damage done.
Gluing in the nozzle would be a Bad IdeaTM. When there is serious overpressure then, as Nytrunner stated, either the nozzle blows out or the delay and ejection grains and clay cap blow out. One lets pressure and flame and burning bits out the bottom of the rocket, the other blows pressure, flame, and burning bits into the rocket. Making the nozzle super strong and super attached is like putting a penny in the fuse box.
I've never had a rocket damaged in a CATO. I've had four engines go BANG and spit their nozzles with no damage done.
As you can see in these photo's of the exact incidents of the CATO the flame from the nozzle is way out of control and large possibly from the clay being blown out and then the flame explodes out the top past the ejection charge ripping the cardboard tube/body to shreds. Maybe a reinforced nozzle and ejection cap would stop this........? 
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Rocketjunkie
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I've flown 167 E9s and 42 E12s. NO catos. Most have come from Hobby Lobby and some from AC Supply.
heada
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Motors are designed so that if they fail, they fail axially and not radially. This is a safety feature. We don't want them to fail but if they're going to fail, this is the desired failure mode. Yes, the rocket is damaged/destroyed but that is better than person/property damnage that could result from a radial failure.As you can see in these photo's of the exact incidents of the CATO the flame from the nozzle is way out of control and large possibly from the clay being blown out and then the flame explodes out the top past the ejection charge ripping the cardboard tube/body to shreds. Maybe a reinforced nozzle and ejection cap would stop this........?
Rocketjunkie
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Many times cardboard cased BP motors fail by splitting the case lengthwise and you have a propellant fireball through the parachute bay.
Spectacular cato and photos. I see two possible actions to take. Contact the manufacturer about your nozzle and cap ideas. And fill out a MESS report: https://www.motorcato.org/As you can see in these photo's of the exact incidents of the CATO the flame from the nozzle is way out of control and large possibly from the clay being blown out and then the flame explodes out the top past the ejection charge ripping the cardboard tube/body to shreds. Maybe a reinforced nozzle and ejection cap would stop this........?
BSNW
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I am wondering if the problems stem from storage (thermo cycling) or certain packs being dropped. I do a TON of D12 and E12 clusters and I pretty much convert just about every model I can the E12 mounts. I have literally flown hundreds of them (E12's) with no issues.
When I go to Hobby Lobby, usually get almost all the packs of E12' on the rack. I sometimes notice that some packs are taped or stapled atthe bottom of the pack, suggesting that the motors may have fallen out the bottom and cracked. IMO, Estes should improve the glue that holds the plastic case to the cardboard backing.
Anyway, hundreds of E12's that either I have flown or seen at the many many launches over a number years, and I have never seen an E12 CATO. I believe their reputation is undeserved. I also have no fear of using them.
Andrew
When I go to Hobby Lobby, usually get almost all the packs of E12' on the rack. I sometimes notice that some packs are taped or stapled atthe bottom of the pack, suggesting that the motors may have fallen out the bottom and cracked. IMO, Estes should improve the glue that holds the plastic case to the cardboard backing.
Anyway, hundreds of E12's that either I have flown or seen at the many many launches over a number years, and I have never seen an E12 CATO. I believe their reputation is undeserved. I also have no fear of using them.
Andrew
Woosher needed 3 E12 0's. First 3 flights ok (9 motors). Then one of 3 Catoed, old pack from LHS. Repaired. Get new pack from another LHS, new Feburary 2021 manufacture date. 2 out of 3 CATO. Repaired. Try another pack of new motors...all 3 ok. Next flight 1 out of 3 CATOED. Repair and retire bird having belly blown out 3 times. Still had a new and old pack. Gave both packs to other ofdroc flyer who used them in Halloween candy dish saucer. All 6 worked just fine. As I saw each launch I cursed Estes as the other flyer praised the reliability long burn performance. The last flight was staged using two, no problem, glorious applause from the crowd. Estes E12 0s rule! What was I so grumpy about? Take your catos like a man! The rocket gods are with you or against you. The Real world baby!
BSNW
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I feel very bad you have had such poor luck with these motors. I am sure many have already mentioned this, but I still wonder if there is some kind of common issue/variable that has to do with storage or dropping. If your LHS is letting them get cold or if the shipper is tossing the boxes, maybe this could be a contributing factor. Seems like there are "clusters" of people who either have no issues or have them explode on a regular basis. I find this interesting. If the error was in manufacturing, I would guess one would see the same rate of failure more evenly distributed all over the country. As a person who launches in Ohio, I don't remember ever seeing one CATO. Nor, have I ever had one fail over hundreds of flights. Yet I hear the E12 is a risky motor. Something (to me) does not add up.
I am sorry about your rocket in the photo. It looks like a beautiful build.
