# Anyone still having E engines explode

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#### Nytrunner

##### Pop lugs, not drugs
TRF Supporter
Couldn't you create a convoluted tube (parallel wound) that has a waxy internally finish with a lower inner paper ring? Is that beyond 21st century technology? Could it not be used with current Estes MABEL technology?
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.

##### Well-Known Member
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.

#### Art Upton

##### Well-Known Member
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

#### Bill S

##### Well-Known Member
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.

#### Bowman

##### Well-Known Member
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? LOL

#### Bowman

##### Well-Known Member
You mean like Toilet Paper right? LOL
Repackaging those rolls into 20-sheet packs for eBay just turned-out to be too much work.

#### Bill S

##### Well-Known Member
I'd like to a video clip of the machine that puts them together.
It can not be cost effective to have each one done by human hands!
You mean like Toilet Paper right? LOL
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 Drifter
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......

##### Well-Known Member
TRF Supporter
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......
... and how much more $$would you be willing to pay for that? BP motors have relatively low ISP (about 1/3 of APCP). Tweaking BP's ISP by 15%, even if achievable, is a marginal improvement compared to transitioning to APCP motors. #### shockie ##### High Plains Drifter ... and how much more$$ 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.

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.

##### Well-Known Member
TRF Supporter
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.
You are missing the point.
Have fun storming the castle.

#### AeroTech

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.
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......

#### shockie

##### High Plains Drifter
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.
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

#### Long_Gone

##### Well-Known Member
TRF Supporter
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 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~

#### Long_Gone

##### Well-Known Member
TRF Supporter
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

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~