Quest Motor ??

[ThreeJsDad]

I did not see any motors on their web sight that do not have an ejection charge. Is it possible to remove the ejection charge on a Quest motor?

 

[KennB]

Item 2 in the NAR Model Rocket Safety Code states:

Motors. I will use only certified, commercially-made model rocket motors, and will not tamper with these motors or use them for any purposes except those recommended by the manufacturer.​

The modification you're asking about constitutes tampering with the motor and would put it outside the Safety Code. You would not be allowed to use it at a launch that is abiding by the Code and it would void any insurance coverage you may have through your organization.

Venting the excess gas, so to speak, is your best bet.

As always happens when this subject comes up on TRF, there will be many expressing opinions that differ in part or in whole with the statement above. You'll have to use your best judgement.

 

[neil_w]

What's your specific use case here? There are usually (not always, but usually) alternatives to modifying the motors. Excess gas venting is certainly one.

 

[ThreeJsDad]

Item 2 in the NAR Model Rocket Safety Code states:

Motors. I will use only certified, commercially-made model rocket motors, and will not tamper with these motors or use them for any purposes except those recommended by the manufacturer.​

The modification you're asking about constitutes tampering with the motor and would put it outside the Safety Code. You would not be allowed to use it at a launch that is abiding by the Code and it would void any insurance coverage you may have through your organization.

Venting the excess gas, so to speak, is your best bet.

As always happens when this subject comes up on TRF, there will be many expressing opinions that differ in part or in whole with the statement above. You'll have to use your best judgement.

Good point, I forgot about that. I did not think it through.

Thank you for not ripping me a new one for my ignorance. My best judgement is to find a more appropriate solution to my design dilemma. I can fly an Estes motor with no charge, problem solved.

 

[ThreeJsDad]

What's your specific use case here? There are usually (not always, but usually) alternatives to modifying the motors. Excess gas venting is certainly one.

That was exactly the issue, I was concerned about. I should only need one ejection charge to handle deployment but I am looking at a three motor cluster.

I apologize for even bringing this up !! It has been a long time since I pursued rocketry as a hobby and have forgotten a bunch of stuff it seems.

 

[ThreeJsDad]

Note sent to Mods to delete this thread

 

[neil_w]

That was exactly the issue, I was concerned about. I should only need one ejection charge to handle deployment but I am looking at a three motor cluster.

Normally you do not want to rely on a single motor's ejection charge in a cluster context. If that motor fails to light (always a possibility), you've got a lawn dart on your hands.

I apologize for even bringing this up !! It has been a long time since I pursued rocketry as a hobby and have forgotten a bunch of stuff it seems.

It's not a problem.

 

[ThreeJsDad]

Normally you do not want to rely on a single motor's ejection charge in a cluster context. If that motor fails to light (always a possibility), you've got a lawn dart on your hands.

It's not a problem.

Good Point, we can discuss this project through PM's or in a build thread as I get closer. My concern was over pressurizing the tube but we can look at that down the road a bit.

 

[neil_w]

Good Point, we can discuss this project through PM's or in a build thread as I get closer.

Use the build thread. There are lots of others (like, almost everyone?) with more clustering know-how than me.

 

[boatgeek]

Item 2 in the NAR Model Rocket Safety Code states:

Motors. I will use only certified, commercially-made model rocket motors, and will not tamper with these motors or use them for any purposes except those recommended by the manufacturer.​

The modification you're asking about constitutes tampering with the motor and would put it outside the Safety Code. You would not be allowed to use it at a launch that is abiding by the Code and it would void any insurance coverage you may have through your organization.

Venting the excess gas, so to speak, is your best bet.

As always happens when this subject comes up on TRF, there will be many expressing opinions that differ in part or in whole with the statement above. You'll have to use your best judgement.

One of the hair splits that happens when this comes up is how much disassembly/mod to the motor needs to happen to remove the charge. For a typical Estes motor, you need to plug/block the forward end of the motor to effectively remove the ejection charge. Most people say that's a mod to the motor and no good. Many single use motors (including the Quests) have a removable cap that you can pull out, pour out the black powder, and replace. Many people (and again, this isn't universal) don't see this as a structural mod to the motor and therefore is allowed by the rules.

If the manufacturer specifically says it's OK to make a change, then it's within the safety code even if it's not in the standard instructions. I don't know if Aerotech/Quest have specifically weighed in on pouring out BP from Quest motors, but I would be interested in knowing that answer. Absent a ruling from the manufacturer, it would be up to the club/RSO/flier to make their own decision.