Club Motor Casing Rental Service

[cwbullet]

Our club is considering a rental service for motor casings. We currently had decided as leadership to propose it to the membership. How many of your clubs have this service, and which motors?

The best options would be 1-2 29mm, 1-2 38mm, and 1-2 54mm cases in the common sizes for certification. I proposed 29/180, 29/240, 38/240, 38/720, and 54/852. Suggestions would be appreciated.

 

[prfesser]

I think your selections would cover at least 80-90% of the L1 and L2 cert flights. There will be some outliers who want to do a minimum-diameter altitude attempt for certification, or something similar, but you can't service everyone (I've always favored keep-it-simple certification anyway).

I don't know how often you have an L3 cert in your club. If several per year, perhaps one 75mm hardware set would be worthwhile and adequate. If it's fewer than that, it's unlikely to be worth consideration. And L3 is so expensive for most flyers that a couple hundred bucks more or less (difference in cost of a DMS vs. a reload) wouldn't make a whole lot of difference.

 

[Handeman]

I think those are good sizes. I would also consider having cleaning brushes for each size available with the case rental. Add a cleaning fee if they don't want to clean the case themselves.

 

[cwbullet]

Any suggestions for CTI casings?

 

[Banzai88]

Any suggestions for CTI casings?

I would NOT recommend any 38 or 54mm CTI cases due to the various issues with those motors.

Nevermind that an investment in said cases, due to the relative scarcity of reloads, is probably not advisable until/unless the supply chain DRAMATICALLY improves for CTI reloads.

 

[Rocketjunkie]

I have a lot of hardware. If you or they work with me, I can bring it to borrow. Of course, the usual 'if you lose it, you replace it' applies. The club does have trackers for rent. I have some CTI hardware also. I do not have 29/180 or 75 mm except 75/3840.

 

[cwbullet]

I have a lot of hardware. If you or they work with me, I can bring it to borrow. Of course, the usual 'if you lose it, you replace it' applies. The club does have trackers for rent. I have some CTI hardware also. I do not have 29/180 or 75 mm except 75/3840.

You lose or damage and you must replace is an absolute.

 

[samtc]

CTI

Three and Six grain cases with spacers. You can fly 1, 2, and 3 grains in a 3 grain and 4, 5, and 6 in a 6 grain. You'll need a tool to adjust the delay for those not flying altimeters.

29 mm 3 and 6, plus 4 spacers
38mm 3 and 6, plus 4 spacers
54 mm 3 and 6, plus 4 spacers

 

[Hobie1dog]

I don't know how often you have an L3 cert in your club. If several per year, perhaps one 75mm hardware set would be worthwhile and adequate And L3 is so expensive for most flyers that a couple hundred bucks more or less (difference in cost of a DMS vs. a reload) wouldn't make a whole lot of difference.

I need all the help I can get financially for a L3 rocket. A 75mm CTI would be needed for the rocket I have picked out.

 

[tim cubbedge]

A long time ago and before my time as prefect, TRA gave our prefecture a handful of AT 29mm and 38mm cases that anyone wishing to certify L1 could use at no charge. We still have all these cases but it’s rare that anyone uses them.

 

[bibbster]

Our club provides that service. Here are the details:

https://midsouthrockets.com/member-benefits/

 

[mtnmanak]

This sounds like a great idea and I think the case sizes Chuck mentioned are pretty indicative of the ones a club would need.

Another option to consider would be to have about 5 each of some of the popular DMS motors on hand and then sell them to cert fliers at cost to avoid any issues with being a "dealer". Cases and closures will break and require maintenance. One CATO will be a significant cost to the club, if the case/closure gets ruined. DMS motors remove the maintenance and damage issue and are essentially a net zero (outside of initial outlay) cost to the club. This option would also help out new fliers by removing the obstacle of obtaining high power loads prior to a launch. You have to put some controls in place to make sure the motors only get used for cert flights, but that should be easy.

I think the following motors would cover most L1 and L2 attempts. Anything outside of these would be something the flier would have to worry about:
29mm H115
38mm H100
38mm H219
38mm J270
54mm J250

Looking at the costs, if you went with the motor cases, the cases you have listed above would cost about $1500 upfront (2 each, with closures), but would incur the costs of ongoing maintenance and replacement.

The initial outlay for the DMS motors would be about $1900, but would be a one time cost as everything in the future would be covered by users buying the motors onsite. The cost to the flier should include the shipping cost prorated into each motor so the club wouldn't pay anything out of pocket. I have a feeling that, over time, you would see some trends in which motors get used more and then could adjust your stock accordingly.

This would also alleviate all the issues with novice fliers having to assemble motors for a cert flight.

I am sure there a lot of reasons this wouldn't be a great idea, but it seems like a possible alternative to cases. That amount of motors is quite small - they would all easily fit in one of the Aerotech shipping boxes, so storage between launches could easily be on someone's garage shelf.

Does Aerotech have any programs in place to support clubs with this kind of thing? It would seem to be good business for them to support this kind of initiative. If every club did this, it would seem like a guarantee of hundreds (thousands?) of DMS sales a year in predictable motor sizes that would streamline the manufacturing costs.

 

[tsmith1315]

That makes sense if there’s no on-site dealer.

@cwbullet Maybe keep a RAS for 29-54 as well, for flyers who have a bigger case than they need, or to expand the range of your club cases?

 

[Steve Shannon]

This sounds like a great idea and I think the case sizes Chuck mentioned are pretty indicative of the ones a club would need.

Another option to consider would be to have about 5 each of some of the popular DMS motors on hand and then sell them to cert fliers at cost to avoid any issues with being a "dealer". Cases and closures will break and require maintenance. One CATO will be a significant cost to the club, if the case/closure gets ruined. DMS motors remove the maintenance and damage issue and are essentially a net zero (outside of initial outlay) cost to the club. This option would also help out new fliers by removing the obstacle of obtaining high power loads prior to a launch. You have to put some controls in place to make sure the motors only get used for cert flights, but that should be easy.

I think the following motors would cover most L1 and L2 attempts. Anything outside of these would be something the flier would have to worry about:
29mm H115
38mm H100
38mm H219
38mm J270
54mm J250

Looking at the costs, if you went with the motor cases, the cases you have listed above would cost about $1500 upfront (2 each, with closures), but would incur the costs of ongoing maintenance and replacement.

The initial outlay for the DMS motors would be about $1900, but would be a one time cost as everything in the future would be covered by users buying the motors onsite. The cost to the flier should include the shipping cost prorated into each motor so the club wouldn't pay anything out of pocket. I have a feeling that, over time, you would see some trends in which motors get used more and then could adjust your stock accordingly.

This would also alleviate all the issues with novice fliers having to assemble motors for a cert flight.

I am sure there a lot of reasons this wouldn't be a great idea, but it seems like a possible alternative to cases. That amount of motors is quite small - they would all easily fit in one of the Aerotech shipping boxes, so storage between launches could easily be on someone's garage shelf.

Does Aerotech have any programs in place to support clubs with this kind of thing? It would seem to be good business for them to support this kind of initiative. If every club did this, it would seem like a guarantee of hundreds (thousands?) of DMS sales a year in predictable motor sizes that would streamline the manufacturing costs.

This post has tons of wisdom in it.
I always share my motor cases and if someone is in need of a reload I open up my magazine and let them borrow a reload.
Two weeks ago a friend wanted to test fly his L3 rocket on a K. His first attempt failed with an aft closure failure when the rear snap ring let go. I suspect it wasn’t fully seated.
So, one thing led to another and I ended up loaning him a CTI K630 reload and 4 grain Pro54 case. I even assembled them for him.
When the motor was ignited it catoed, forcing the forward closure up through the rolled case end. My friend looked at me and said “do I have to pay you for that?” Of course there was no way I could charge him for that, but now I’m out over $300 for a case, aft closure, and reload. I presume CTI will make it good, but while I wait to find out I’m unable to use or loan CTI Pro54 cases or reloads and I’m much less comfortable providing motors to people.

 

[sharkbait]

This sounds like a great idea and I think the case sizes Chuck mentioned are pretty indicative of the ones a club would need.

Another option to consider would be to have about 5 each of some of the popular DMS motors on hand and then sell them to cert fliers at cost to avoid any issues with being a "dealer". Cases and closures will break and require maintenance. One CATO will be a significant cost to the club, if the case/closure gets ruined. DMS motors remove the maintenance and damage issue and are essentially a net zero (outside of initial outlay) cost to the club. This option would also help out new fliers by removing the obstacle of obtaining high power loads prior to a launch. You have to put some controls in place to make sure the motors only get used for cert flights, but that should be easy.

I think the following motors would cover most L1 and L2 attempts. Anything outside of these would be something the flier would have to worry about:
29mm H115
38mm H100
38mm H219
38mm J270
54mm J250

Looking at the costs, if you went with the motor cases, the cases you have listed above would cost about $1500 upfront (2 each, with closures), but would incur the costs of ongoing maintenance and replacement.

The initial outlay for the DMS motors would be about $1900, but would be a one time cost as everything in the future would be covered by users buying the motors onsite. The cost to the flier should include the shipping cost prorated into each motor so the club wouldn't pay anything out of pocket. I have a feeling that, over time, you would see some trends in which motors get used more and then could adjust your stock accordingly.

This would also alleviate all the issues with novice fliers having to assemble motors for a cert flight.

I am sure there a lot of reasons this wouldn't be a great idea, but it seems like a possible alternative to cases. That amount of motors is quite small - they would all easily fit in one of the Aerotech shipping boxes, so storage between launches could easily be on someone's garage shelf.

Does Aerotech have any programs in place to support clubs with this kind of thing? It would seem to be good business for them to support this kind of initiative. If every club did this, it would seem like a guarantee of hundreds (thousands?) of DMS sales a year in predictable motor sizes that would streamline the manufacturing costs.

Our cert’s have changed dramatically over the past few years, it’s no longer one or two people ever once in a while, it’s a large group of 12-15 from one of the colleges. Hard to service that with club hardware or club DMS’s. We have a club e-mail that goes out including our on site vendor to try and address everyone’s needs for the upcoming launch. Usually one of our members can bring and loan whatever is needed and most of the students buy a DMS from our vendor.

 

[mtnmanak]

Our cert’s have changed dramatically over the past few years, it’s no longer one or two people ever once in a while, it’s a large group of 12-15 from one of the colleges. Hard to service that with club hardware or club DMS’s. We have a club e-mail that goes out including our on site vendor to try and address everyone’s needs for the upcoming launch. Usually one of our members can bring and loan whatever is needed and most of the students buy a DMS from our vendor.

Agreed - the volume of cert flights would have to be taken into account. I think, if the club wanted to have some kind of loaner case/DMS availability, you would have to have a policy covering college teams (if that is a thing at the club - some clubs have to deal with this, some don't). Basically, it would be something like "Groups need to bring their own motors" or something like that. I can't speak for Chuck, but I am sensing this is to help out individuals who come to the club looking for help with the motor on an L1/L2 cert flight, not a program to provide bulk motors to college teams (which I think already is a program from Aerotech?).

Either way, if you are going to think about providing motor help, it seems to me that either loaner cases or DMS availability would work. I think I would prefer DMS in order to cut down on the cost/overhead/work (I imagine club officers would spend a significant portion of a weekend showing novice fliers how to assemble motors if you had loaner cases), but loaner cases would still be very cool.

This post has tons of wisdom in it.
I always share my motor cases and if someone is in need of a reload I open up my magazine and let them borrow a reload.
Two weeks ago a friend wanted to test fly his L3 rocket on a K. His first attempt failed with an aft closure failure when the rear snap ring let go. I suspect it wasn’t fully seated.
So, one thing led to another and I ended up loaning him a CTI K630 reload and 4 grain Pro54 case. I even assembled them for him.
When the motor was ignited it catoed, forcing the forward closure up through the rolled case end. My friend looked at me and said “do I have to pay you for that?” Of course there was no way I could charge him for that, but now I’m out over $300 for a case, aft closure, and reload. I presume CTI will make it good, but while I wait to find out I’m unable to use or loan CTI Pro54 cases or reloads and I’m much less comfortable providing motors to people.

Have to agree with you Steve - I am almost always willing to help out folks with loaner cases and motors at a launch, but I had a loaner CATO last year and it is really difficult to watch your expensive case go sideways in someone else's rocket... And, if you assemble the motor for them and it CATOs, I am worried they will come ask me to pay for their rocket. These days, I only loan cases out to folks I know well and default to selling DMS motors to people at a launch if I don't know them and they need something. I helped quite a few L1s out last year like that when the onsite vendor ran out of H motors.

 

[Handeman]

I imagine club officers would spend a significant portion of a weekend showing novice fliers how to assemble motors if you had loaner cases

It's not just loaner cases where you spend time. With some college teams, they come with a few cases, but reloads for everyone and pass the cases on as each group returns from their attempts. In many cases, their L1 attempt is the first rocket they have ever built. We have learned and now require all motor assembly to be monitored by an experienced club member and an extensive RSO inspection. Fortunately most teams are very good about contacting us well ahead of the launch with their plans so we can be ready.

 

[speed]

Our club has motor cases available to loan. No charge unless you lose it or the failure isn't covered by Aerotech. No CTI cases.

 

[mtnmanak]

It's not just loaner cases where you spend time. With some college teams, they come with a few cases, but reloads for everyone and pass the cases on as each group returns from their attempts. In many cases, their L1 attempt is the first rocket they have ever built. We have learned and now require all motor assembly to be monitored by an experienced club member and an extensive RSO inspection. Fortunately most teams are very good about contacting us well ahead of the launch with their plans so we can be ready.

Agree - I have seen this as well.

Thinking about it, it is not a bad thing, I guess. It is important to teach folks how to do these things right and it draws more young people into the hobby, which is always a good thing. There are always a lot of people around at a launch that can help out. I have to admit, I am getting to an age where I am only good for either one big launch on a weekend or a few smaller launches (or, more and more, no launches...). So I do have more time now to help out people that need it.

 

[Voyhager3]

This is a good idea, and I’ll definitely keep this in mind when I go for my L2 later, as it would definitely lessen the financial burden. I think the 29/180/240 would be great, as I’ve seen a lot of L1s done on this size, as you could do a sub 1k L1 on those. And maybe a 38/240/360 for those bigger rockets/ L2 capable rockets. And also maybe a 38/1080 for those L2s on 38s. Then some 54s for L2s/ the big j and small K cases for those larger Rockets. And maybe a small M 75 case for those L3s.

Another idea would be to have a program for people to also be able to buy maybe just the 29mm L1 Motors. Because they could be preordered for cheap. However, I guess this would have to be a lot of paper work, as you would now be selling them. But just a thought on how to get more people in the hobby.

 

[Hobie1dog]

Another idea would be to have a program for people to also be able to buy maybe just the 29mm L1 Motors. Because they could be preordered for cheap. However, I guess this would have to be a lot of paper work, as you would now be selling them.

That's what Ken is for

 

[Steve Shannon]

Have to agree with you Steve - I am almost always willing to help out folks with loaner cases and motors at a launch, but I had a loaner CATO last year and it is really difficult to watch your expensive case go sideways in someone else's rocket... And, if you assemble the motor for them and it CATOs, I am worried they will come ask me to pay for their rocket.

Exactly - when he said he wanted a shakedown cruise this wasn't what he signed up for! Fortunately the damage to his rocket was pretty minimal and he took it with a good attitude, especially after I said that he didn't have to pay for it also.

 

[jhill9693]

I need all the help I can get financially for a L3 rocket. A 75mm CTI would be needed for the rocket I have picked out.

Same here.

 

[cwbullet]

Same here.

That is a tough one because it is $437. Renters would sign an "I will replace if lost or destroyed" guarantee. That is a lot fo cash for a small club to cough up for 1-2 flights a year.

 

[prfesser]

After looking over the loads available I considered a slightly different arrangement. The 29/180 for ordinary smaller rockets; include an adapter for 38mm MMTs. For heavier ones or for higher-altitude flights the 38/360 has a wide variety of loads: I218 or I245 for somewhat bigger rockets; H550 or I357 for much bigger ones or for extreme flights.

For L2 the 38/720 has enough variety for almost any reasonable rocket: J340, J350, J420, J500. Again, an adapter for 54mm MMT. Just three sets of hardware to cover most L1 and L2 certs.

The objective is to provide assistance for newbies and for those attempting to cut costs a bit. It's not practical to attempt to cover every possible cert flight, and the flyer should be aware of what is available at the club before deciding on the project itself.

 

[Banzai88]

That is a tough one because it is $437. Renters would sign an "I will replace if lost or destroyed" guarantee. That is a lot fo cash for a small club to cough up for 1-2 flights a year.

That's fully 1/3rd of the annual budget of my local club.

If a flyer doesn't have the money up front to buy a case of that level, chances are that they won't have it on the back end, either. And regardless of the signed agreement, what recourse would the club have if the flyer just ghosted (either with the case, or with replacement obligation)?

 

[firemanup]

That's fully 1/3rd of the annual budget of my local club.

If a flyer doesn't have the money up front to buy a case of that level, chances are that they won't have it on the back end, either. And regardless of the signed agreement, what recourse would the club have if the flyer just ghosted (either with the case, or with replacement obligation)?

Exactly what I was thinking as well.

 

[jmasterj]

That's fully 1/3rd of the annual budget of my local club.

If a flyer doesn't have the money up front to buy a case of that level, chances are that they won't have it on the back end, either. And regardless of the signed agreement, what recourse would the club have if the flyer just ghosted (either with the case, or with replacement obligation)?

Agreed. If you can't afford the equipment for your L3 cert, what's the point? At least AT 38/720 hardware is pretty affordable for L2. If I was on a BoD (and I'm not), I would consider the L1 stuff but probably vote against having L2 hardware/motors to lend out. Once a flyer has L1, there's plenty of HAZ motors and such they could combine with an L2 motor purchase to not make it feel so expensive for one motor.

 

[ksaves2]

Our prefect used to loan out casings for fliers. The understanding was (as mentioned) you lose it or blow it, you buy a replacement.
I've had three burn throughs on my 29mm casings. Two with commercial loads and one with a research load over the years.
Haven't had a burn through with AT 38's but I use a thick walled McMaster-Carr Garolite liner with the research stuff. Can get three burns on one liner it's
that tough and stands up to cleaning! Kurt

 

[Handeman]

Our club is currently a Tripoli only club and we fly when the landowner crops are not in, usually Oct. to Apr. The club does not have any cases to loan out. We still had over 80 L1, L2, & L3 cert attempts this flying season. That was just the Tripoli certs where the prefect was involved. We're estimating there were upwards of 2 dozen NAR certs also.
Having cases to loan out sounds like a good idea, but I'm not sure its really needed or will get used that much. If a flier can't afford a case for their cert motor, what are they going to fly their new cert level motors in? The CTI grain spacers and AT RAS are good ways to reduce cost for a flier while allowing them to fly a range of motors in their new cert level. If they don't intend to fly enough to want to invest in motor cases, DMS is a viable option both for the cert flight and later launches.