jimzcatz
Boss, Carolina Rocket Mafia
Impossible. You can't drill below 4 seconds, the motor won't contain the pressure
Can you change delay on a single use motor?
- Thread starter BABAR
- Start date
thanks jimzcatz , just saved 40 bucks not ordering them 
Nytrunner
Pop lugs, not drugs
There are not zero-delay composite motors. Composites have a core (hole) up through the middle that exposes the front bulkhead (and delay grain) to the full chamber pressure.
Drilling the delay of a composite motor too short (under 3-4 seconds) is a smooth way to have your rocket start burning out both ends.
Composite staging is achieved using electronics set to ignite the upper stage(s) at or shortly after Booster burnout.
So remove Powder charge in booster and ignite second stage with Aux out of my Avionics package. I have that ability with a time delay charge set on a liftoff time + Burntime and allow .5 delay for some coast time. So I can remove the F52 deployment charge and epoxy the hole shut then?
Nytrunner
Pop lugs, not drugs
That scheme should work!
- Joined
- Jan 30, 2016
- Messages
- 8,716
- Reaction score
- 3,105
Should work fine, skip to 4:45 or so to jump straight to composites.
Thanks I love the company Apogee , have done a good amount of business with them. His videos are always excellent for reference too.
- Joined
- Jan 30, 2016
- Messages
- 8,716
- Reaction score
- 3,105
Zooming in on this piece -- are you just going to separate via the top stage exhaust? Any tilt inhibit?
Lots of opinions here. Here’s mine:
Can you? Sure, if you’re creative. Is it legal, covered by insurance, or allowed by your RSO? That’s another story. Know the answers to all of these before deciding whether to do it and commit to launching. Ask for help from those more experienced and knowledgeable than you are, and don’t try to be sneaky. That’s a good way for a mistake to shut us all down.
Whatever you decide, please do it safely. You can always pick a different rocket or a different motor.
Can you? Sure, if you’re creative. Is it legal, covered by insurance, or allowed by your RSO? That’s another story. Know the answers to all of these before deciding whether to do it and commit to launching. Ask for help from those more experienced and knowledgeable than you are, and don’t try to be sneaky. That’s a good way for a mistake to shut us all down.
Whatever you decide, please do it safely. You can always pick a different rocket or a different motor.
No Tilt inhibit. But my plan was to have the second stage to just exhaust it off. Fairly loose fit so the booster can come off easily and tumble recovery.
Well I have been simulating in OpenRocket and I could do a 3 second delay. But I am not sure about tilt as mentioned by DhBarr. Maybe should &^%$can the 2 stage idea and enlarge my motor and pull out the delay charge. I like using the dual deploy systems and prefer that over single chute at over a 1500 ft. I do not feel like chasing the rocket for a 1/2 mile. Just my preference with dual deploy systems over 24 or 36 inch chute at higher altitudes.
or allowed by your RSO? . I have a certified Level 3 rocketeer that is overseeing my launches and mentoring. But he flies motors that I cannot afford nor do I have the expertise to build or launch. We have a 600 acre field that we have permission to use for test rockets and entertainment purposes with the grandkids.
What is killing me is the prohibitive costs for shipping on larger mid to high power motors. I have to rely on our monthly launches to get larger motors from club members that do resale on Cesaroni motor refills. I like the Aerotech approach but their costs are also prohibitive on Mid to High power reloadable Motor casings. I am a retiree and Budget limitations have kept me in the 29mm motors for the time being. None of our local Hobby Shops (within 100 miles) sells High Power H Cesaroni refills. For my Level 1 I had to get a friend bring my H motor Cesaroni refill to the Launch because he happened to have one on hand that he had not used. The shipping costs are going to ruin the Hobby IMHO!
tsmith1315
Well-Known Member
Hazmat shipping is nothing new. If it were going to ruin the hobby, it would have done so decades ago. No worries there.
That said, I am in the same situation as you. I can't buy in sufficient quantity to justify the hazmat costs. There are plenty of reloads that don't require hazmat shipping, up to J impulse. Aerotech and Loki have select motors 38mm and smaller that are hazmat-free.
Check out FlightSketch.com, they offer free shipping on orders over $35.00
I am fortunate enough to have two clubs within a doable drive that frequently have motor vendors onsite. They’re more reliable for the big regional launch events but sometimes they’ll turn up at the monthlies.
So hazmat isn’t a universal concern, plenty of people can buy on-site or pick up orders on launch day. Others will make do with what’s available non-hazmat, or bite the bullet and cough up.
- Joined
- Jan 17, 2010
- Messages
- 767
- Reaction score
- 775
Motors are expensive, and will continue to get more expensive for the foreseeable future.
Fortunately, there are at least a few ways to save a bit of money here and there.
First, shop around. Many vendors offer discounts, with Balsa Machining offering 25% off of high power reloads if you preorder them. If you pay $30 a year for Wildman Club, you can get non hazmat hobbyline G reloads for $17.50. Wildman also has a great sale every year around Black Friday, with deeper discounts available to club members on Wednesday, and slightly less good prices for everyone else on Saturday. There are also some vendors that don't offer good prices, to the point of marking motors up significantly above MSRP.
Secondly, look for deals on used motor hardware and second hand motors. I picked up a 29/40-120 case on here for $40 a few months back. I mostly look at the yard sale section on here, but I believe that there are also Facebook groups, and your local club members might also want to sell some stuff.
Thirdly, there are options to avoid Hazmat shipping, that aren't always apparent. All Cesaroni motors need the Hazmat fee, but many Aerotech and Loki motors up to J impulse don't need it. Hazmat fees are based off of the mass of the largest piece of propellant, so for example, most of the G reloads for the 29/40-120 casing don't need the fee because they use two propellant grains, but the F reloads do, because they use a single grain longer than the G grains. Most of the Aerotech 29mm HPR style motors don't need Hazmat fees, but the denser Blackjack motors do need them. The biggest single use motors that don't need Hazmat fees are the Econojet F motors.
Finally, if you need to buy stuff that needs Hazmat shipping, buy as much as you can at once to dilute the price of shipping. It can double the price of a H reload, but is an easier pill to swallow on a larger order. Either save up to do a larger motor purchase at once, or pool orders with some friends so that you can split the shipping costs. I've been personally saving up my hobby funds for a while now in preparation for the Wildman sale, where I'm planning to buy most of my high power motors for next year.
I hope that this advice helps. I don't know what your exact fincancial situation is, but I hope that I can at least point you in the direction where your dollars will go the furthest.
I have two Aerotech G70 29mm single use motors, and they came with the delay tool, and instructions.
How old are they? Do they pre-date 03-23-2022?
Yes. What did I miss? I'm hoping to fly two of the wonderful rockets I got from DragonRocketry.
Yes. What did I miss? I'm hoping to fly two of the wonderful rockets I got from DragonRocketry.
Folks were drilling the delays on Single Use Aerotech motors. Other folks thought that was in violation of the NAR code.
NAR and Aerotech clarified the issue, as stated in post #47 above.
- Joined
- Jan 30, 2016
- Messages
- 8,716
- Reaction score
- 3,105
Safely, thousands of times, for actual decades.
Some folks pressed and pressed for tablets of stone.
It is now removed from an RSO judgment call into the realm of thou-shalt-not / thus-saith-the-board.
Thanks; I missed that. So these are not meant to be modded. I'll make a note.
I haven't finished either rocket, and anything else I have will not live thru a G- motor.
I have to admit, the little kid in me wanted to take my Tomahawk upscale and destroy it with a G-motor, lol. But that's not cool for adults.
I haven't finished either rocket, and anything else I have will not live thru a G- motor.
I have to admit, the little kid in me wanted to take my Tomahawk upscale and destroy it with a G-motor, lol. But that's not cool for adults.
- Joined
- Dec 17, 2009
- Messages
- 1,167
- Reaction score
- 3,138
I’d like to see a picture of the tool. Who sent it to you?
jimzcatz
Boss, Carolina Rocket Mafia
I use the Synerjet tool, works on every motor ever made, SU or reload. But honestly, I'm not changing delays very often.
mtnmanak
™
- Joined
- May 5, 2020
- Messages
- 1,742
- Reaction score
- 2,110
Since you are in Maryland, you do have an option - plan ahead and buy motors from Wildman (Tim Lehr) during his Black Wednesday/Saturday sale (this coming weekend). Then, call them up and tell him (well, Jackie most likely) that you want him to deliver your motors at Red Glare in the spring at MDRA. They will refund your shipping and HAZMAT charges and, voilà, you will get on-sale motors with no shipping or HAZMAT fees in March/April.
I have to admit, the little kid in me wanted to take my Tomahawk upscale and destroy it with a G-motor, lol. But that's not cool for adults.
Says who??
Says the father who taught three learner drivers to do handbrake turns on gravel yesterday.
Oh wait, that was me. As you were...
Similar threads
