Critique my venture into reloads

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DigBaddy

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As mentioned in the 2022 unofficial goals thread, I want to get into reloads this year and almost certainly go for L1 HPR. After a few recent builds, it's dawned on me that reloads are a likely path forward with my flying. We (my son and I) have a good assortment of 24mm rockets and now several 29mm birds that can handle H impulse (and I in the MDRM I built). The 29mm rockets range in weights from 12oz to 37oz. Nothing 38mm (yet). So, what I'm thinking and any input toward this plan is welcome.

AT 24/40. Seems like a really good value in case and motors. Some of the 29mm rockets can even fly on reloads in this case (29mm Big Daddy and Super Big Bertha). Reloads for this case come in a few bucks cheaper than SU motors, and I can tailor delays easily. Seems like the case and delay tool will pay for itself in just a few flights. I don't see a reason to not get this.

AT 29/40-120. Another easy choice, I think. Good selection of loads can fill in gaps with some SU 29mm E-G motors if needed, but my sims say I can get a lot of use out of this as well. Pretty easy to make up the cost over SU motors; maybe even in a single day of flying.

Now, here's a curveball, the route to L1 gives me a few options
1. CTI 29SK (3G case, spacers, DDT) and adding a 6G case to cover a wider range of loads. About $100
+ less hardware cost and includes a DDT
+ Quite flexible in reloads I can use; everything 1-6G which is >40 motors.
+ Lots of H loads which could handle larger 29mm and 38mm rockets when adapted down.
- Not like the AT stuff I would buy anyway; so different. More to learn (not really a downside)
- 1-2G reloads more expensive than AT 29/40-120 reloads so it doesn't seem like this is quite a viable replacement for 29/40-120.
2. AT 2918SC (180/360 cases, spacers and closures) ~$130
+ Would already be familiar with AT from 24/40 and 29/40-120
+ Would have AT DDT from the other AT hardware
- Less motor choices in that style, so would really need 29/40-120 as well.

So, I'm leaning CTI for H and up and going with the 24/40 and 29/40-120. Now, am I crazy or does this seem reasonable? If I got the CTI route as listed for larger motors, and can benefit from being able to run smaller CTI reloads, is it worth going 29/40-120 then? I'm really blind to the reload game and have a lot to learn, so pointers to consider and experiences others have gained is most welcome.
 
There’s nothing wrong with what you’re considering, but I would suggest looking for used cases. There are lots of used cases in those sizes out there. Many of us no longer use the smaller cases because we have switched entirely to high power flying. Put out a want ad or let people know with your nearest club.
 
I think one thing that bears mentioning when considering CTI vs. Aerotech for 29mm, is that since they are totally disassembled, a lot more 29mm Aerotech reloads ship without hazmat shipping than CTI reloads. This might not be a concern if you have a nearby vendor to buy motors from face-to-face, but if you're planning to have a lot of 29mm reloads shipped to you, you might want to consider leaning toward Aerotech.
 
I think one thing that bears mentioning when considering CTI vs. Aerotech for 29mm, is that since they are totally disassembled, a lot more 29mm Aerotech reloads ship without hazmat shipping than CTI reloads. This might not be a concern if you have a nearby vendor to buy motors from face-to-face, but if you're planning to have a lot of 29mm reloads shipped to you, you might want to consider leaning toward Aerotech.

Oh! Wildman is at a lot/most club launches so face-to-face pickup is possible. Sometimes I may want/need motors shipped though. Thanks for that insight, I didn't even think of that.
 
One other thing if you're getting into reloads for the first time. My old mentor impressed it on me and I have ever since impressed it on anyone that I helped assemble a motor for the first time:

Reloads do not come with extra parts. If you finish assembling the motor and notice an o-ring or something still sitting on your table, you did something wrong and need to figure out what you missed.
 
I like the CTI for staging. A lot. Enough to forgive the occasional CATO.

Along with shipability, you may also want to consider that sometimes Tim's selection of CTI gets a little thin - though I supposed that AT supply issues can happen, too.

For what it's worth, Tim will -gladly- sell you BOTH.
 
Been flying the 29/40-120 case for 25 years now. One thing is what does your vender at the launch sell.

Just as Charles mentions above, Tim sells both AT and CTI. So, being able to grab something at a launch and/or pick up an order is easily doable. My only personal challenge is that most spring/summer/fall launches fall on weekends when my son and I are racing mountain bikes, so coordinating a pickup might be trickier, but something I would just have to work out.
 
I use the 18mm to 29/40-120mm AT Hobbyline cases for low and midpower rockets. For HPR, I use 29mm to 54mm CTI cases. I do prefer the CTI cases, mainly for their ease of use. Cleaning them is simple as well.
 
When you are at a club launch, tape a sign on your table asking for 24/40 & 29/120 Hobby cases and reloads. Have cash. You can score some great deals. The folks at your club are much better to deal with than on-line. Try it for a few months, you will be glad you did.
 
The AT 29mm 40-120 case is the most versatile mid power reloadable case on the market. I love mine and the fact it handles reloads ranging from E to G impulse.
+1, G64W and G76G are the most fun you can have without a HazMat fee or a waiver.

Test flight on a G76G, L1 on an H97J ( 29 / 240 ) or H135W ( SU ).
 
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I have yet to fly a lot of reloads, in fact I’ve only got two flights with them so far. I will say, however, that I’ve been satisfied with my flights on E23Ts in the Aerotech RMS 29/40-120 casing.

Preflight, however, was a pain. You can do great things with reloadables, but as it stands, I hate them. Hopefully this will wane with further practice, though.

That said, the most important things I learned are:
  1. Identify and be familiar with the hardware components before attempting to assemble. That’s your casing, your forward closure, and your aft closure. I made the mistake of thinking that the forward closure on my knockoff RMS 18/20 was an integral part of the casing when in fact it screws on like the rear one does. In my confusion, I decided to abort the load, but doing this ruined the propellant grains and the casing (more on this in a second). Watch a tutorial video, ask the forum, or contact the manufacturer if you have even the slightest question about how to assemble.
  2. Study and follow the instructions very carefully. Understand the components and their purpose. Unless you’ve really dived into the specifics of how these things work beforehand, some of these components will probably be alien to you, the way that a lot of airframe and GSE components probably were for your first rocket build. Again, pose any questions to the Internet or the manufacturer.
  3. Aerotech liner tubes sometimes don’t fit correctly as is. If the fit is anything less than smooth and effortless, peel and/or cut away the outer layer of the liner tube’s paper until the liner tube assembly slides in the casing without you having to muscle it in. Trying to force it in with tools or banging them together will only get the liner tube stuck in the wrong position or damage it. Or both.
  4. Your complete hardware set(s) will probably come with a small tube of lubricant, but you’ll also want to buy or commandeer a tub of petroleum jelly and apply it liberally to the exterior of the liner tube. It will further improve the fit and also make cleaning out residue easier. Do not think of lubricant as a substitute for any needed trimming, though. If you need to remove the liner tube assembly, a slippery liner tube will make it that much harder. Be careful not to get the jelly on the grains, though. It might physically damage them or interfere with their burn properties.
  5. Enlist the assistance of somebody who is familiar with your reload, if possible. A little bit of supervision would have saved me some money and frustration.
  6. Place your orders well ahead of time. I ordered a couple of Aerotech E16W reloads via Animal Motor Works in November. They still haven’t arrived, since Aerotech was having some distribution problems that delayed everything by an estimated 15 weeks. Currently they’re not expected to arrive until the end of February, so my next 29mm flights will be with Estes black powder E16s.
 
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I've been flying Aerotech since I got back into the hobby. I've been completely happy with their products and customer service. I can't really offer an opinion on CTI. That said, The 29-40/120 case is my favorite and most versatile case for hobby flying at my local parks/field. G64W and G76G are my go-to loads and relatively cheap especially if you grab your seasonal supply during a black friday sale like Wildman runs. Also, with Wildman local to you.. I would recommend joining the Wildman Club... if you pick up aerotech hardware and reloads... it will repay itself almost instantly on the discounts you receive on hardware and reloads... and with Tim local/at your launches... no shipping! The 29/180 through 360 cases are also ones that I have flown a lot. Did my L1 cert on the 29/180 and in the 240 case, the H180, 210R, and 250G are all great motors. I dont fly the 29/360 too often but the H268R and the I200W are good as well. Even being L3, the 29/180 and 29/240 cases are still motors that I fly at almost every launch... so much so that I have 2 complete sets the cases.
 
A lot of good advice here.

My most often used cases are the 24/40 and 29/40-120. Most cost-effective route for E/F/G reloads, as long as you don't lose cases. For WOOSH folks, they're also available at Hiawatha Hobbies if needed for non-Bong launches.

For H motors, my preference is AT, I fly the 29/180 and 29/240 cases more than any other HPR cases. The 29/360 is the cheapest way to fly an I motor, I've flown probably a dozen I200 motors in my Mega Der Red Max (I know it's barely an I, but it's still fun!)

I prefer AT RMS since I'm building the whole thing - if it CATOs, it's almost certainly my fault. The only AT RMS CATO I've had is with their EZ reloads, which were fortunately discontinued quickly (due to manufacturer caused CATOs). Once you've cut your teeth on the HobbyLine RMS, the HPR RMS-Plus motors are a breeze to build - but DO follow the instructions, as HPR cases assemble different than HobbyLine cases.

Of course, AT RMS takes longer to build and clean than CTI. That's the main downside. Seems the 29/38mm AT reloads used to cost less than CTI, but retail costs are close now. Unless, of course, you get a big batch from Wildman during the annual sale. :D
 
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<snip> Even being L3, the 29/180 and 29/240 cases are still motors that I fly at almost every launch... so much so that I have 2 complete sets the cases.
Only 2 sets? I'm up to 4 of the 29/180 + 29/240! But only 2 of the 29/100, 29/120 & 29/360. I need to do something about that. :rolleyes:
 
I will echo the 24/40 and 29/40-120 cases being great. The former covers Es and a nice small F, while the latter has great Gs and bigger Fs (though I've avoided the Fs because of hazmat shipping). 24/60 only makes sense if you really want those loads, other wise it's much more costly per N-s than the 24/40. I use it for non-haz, hard-hitting Fs. 29/40-120 is basically a G case for me.
 
I have been looking into the 24mm and 29mm propellant sticks at RCS rocket components. I see that they also sell liners and o-rings and nozzles. Anyone have any experience in making your own reloads from these components? Would it be less expensive this way?
 
Only 2 sets? I'm up to 4 of the 29/180 + 29/240! But only 2 of the 29/100, 29/120 & 29/360. I need to do something about that. :rolleyes:

LoL, yeah, only 2 sets of the 29… and 2 sets of everything above 29 as well!
 
I have been looking into the 24mm and 29mm propellant sticks at RCS rocket components. I see that they also sell liners and o-rings and nozzles. Anyone have any experience in making your own reloads from these components? Would it be less expensive this way?
Likely not, as a) you'll probably CATO a lot more, at least initially and b) tooling, jigs, storage space, and your time are all not free

Further, you'd need to be TRA L2 and only fly them as research / experimental to use them at any events.
 
Here's what I decided on. The two cases and RAS in 29 and 38 gives about 33 motor choices. I have to point out that the Warp 9 reloads are plugged, and require an altimeter for ejection.
 

Attachments

  • 29mm - 38mm RAS loads.pdf
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Here's what I decided on. The two cases and RAS in 29 and 38 gives about 33 motor choices. I have to point out that the Warp 9 reloads are plugged, and require an altimeter for ejection.
Adapting from 29/360 to 29/240 requires two spacers, the max number certified. Can't adapt a 29/180 reload into a 29/360 case.
 
As a side comment, not to hijack, remember that you can assemble the motors prior to going to a launch.
It is much nicer to assemble sitting at a workbench than on a folding table outdoors in the wind.....

More than 1 of the hobby line motor casings is handy for this sort of thing.

I have successfully burned motors that had been sitting assembled for a year (in a ziplock with all the air squeezed out). I have also unsuccessfully burned a motor that had sat for about 2 years.
YMMV
 
Adapting from 29/360 to 29/240 requires two spacers, the max number certified. Can't adapt a 29/180 reload into a 29/360 case.

Zakly right. I've got a "hobby" case, a 29/40-120, and two 29mm "high power" cases, 29/180 and 29/360. Sorry if that wasn't clear. I've also picked up 38/360 and 38/720 cases. That covers more than what's in the list I posted, but the opportunity came along and the price was right. Sometime, maybe next year, I'll look at 54mm cases. (right after I win the lottery...)
 
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