L2 Questions?

[AfterBurners]

So its that time for me to bite the bullet and move up to get my L2 certification and as always relying on the input from you guys for some possible suggestions? Sharing your L2 stories are always welcomed and your experiences during the process.

So why now for me? Its just time, but time is a commodity for me, yet I decided if I was going to build another rocket I want to gain experience and move forward.

A few things I would like to know are listed below, but please feel free to add to it and thank you again for your suggestions and input.

1. Kit or scratch build - Kit suggestions?
2. Materials - If I choose fiberglass what are some of the safety precautions to follow when working with it?
3. Electronics - Altimeter suggestions?
4. Tracking devices - When do you determine a tracking device is necessary?
5. Target Altitude - Whats a good altitude to shoot for?
6. Test Questions - I know there are questions on the NAR website, but how did most of you study? How did some of you study? Was it knowledge or memorize the Q&A
7. Discounts - Are discounts available through some vendors for certification flights?

Anyway that's all I have for now, but I'm sure there's more I can think of. As mentioned before your input is greatly appreciated.

Thank You!!

AB

 

[dhbarr]

Which field / ceiling? Local launch or regional?

The standard advice is to get a vanilla 4fnc ( no aft sweep ) fiberglass bird, send it up low and slow, and do it at a launch where you'll have plenty of air & eyes.

 

[Steve Shannon]

Afterburners,
You’ve been around quite a while. I commend you for not having rushed the experience.
With the experience you’ve gained, what appeals to you? What sounds fun?
You’ll do great. Enjoy!
My failed first attempt was the one thing I didn’t expect, motor retention using plastic hooks to hold the motor (dumb, I now know). I flew it a second flight (be sure to have a second motor) using masking tape retention.
(In my opinion) Only do things with the cert flight if you have experience with them and want to. So if you want to use electronics, get some experience using electronics in Level 1 flights first. Your goal is to certify safely.

 

[boatgeek]

Kit/scratch: whatever you prefer. There are lots of great kits out there or good experience to be had building scratch. Since you want to stretch yourself, a 54mm kit offers more room to grow than a 38mm kit. Simple and robust are good features.

Fiberglass: minimum half mask respirator with dust filters if you are dry cutting and sanding. That’s to keep you healthy. Long sleeves or a Tyvek suit and or barrier cream will help keep you less itchy.

Altimeters: I’m a fan of Eggfinder products and the Chute Release but they don’t float everyone’s boat. If you go redundant, you can have a small simple altimeter (Quark, RRC2+) and a recording altimeter (Quantum, RRC3, etc.).

Tracking: it’s hard to see a 4” rocket above about 5,000 feet. You can scale that altitude up or down by diameter or how good your eyes are. Definitely track if it’s out of sight and it’s not a bad idea any time.

Altitude: I just flew to what a small J took me to. It’s a good idea to keep it in sight if you can.

Test: I just committed the test questions to short term memory before taking the test and knew where to find info if I needed it later.

Discounts: some manufacturers have a very special where you get a free casing when you buy one or two loads. I just saw it advertised on AMW’s site but don’t know if anyone else is doing that now. Aerotech DMS loads are also a solid choice.

 

[wsume99]

I'm actually going thru this process myself right now. My L1 bird is built and sitting ready. I even have the motor. I've just been waiting for the weather to cooperate. Hopefully next Saturday is the day. In the meantime I've been researching and learning. Figuring out how to proceed towards L2.

My advice is to do something you want and find enjoyable. Don't cert just for the sake of certifying. So what kinds of things do you find interesting? Once you determine than then questions 1-5 can be answered better.

For me I am building a 3" Punisher. I wanted something that was durable and flexible. That could fly on baby H up thru full K and something that would allow me to step thru things and types of flying as I learned more. The Punisher fit the bill for me - 3" diamter fiberglass that's just about 5' long. I can fly it on a three grain H with motor deployment to 500' or a 6 grain K/baby L to almost 15k'. Those are two very different flights requiting totally different skills. So that's my 2 cents.

A couple words about working with fiberglass. A lot of people recommend washing all the parts in soapy warm water before you start assembly. I would add that you should take some 220 grit paper and knock the edge off of all the cut edges before washing the parts. A lot of the cuts have sharp fine bur's in my experience.

Lastly, good luck and I hope you get some great advice because I'll be following along and hopefully I can learn something too.

 

[AfterBurners]

Which field / ceiling? Local launch or regional?

The standard advice is to get a vanilla 4fnc ( no aft sweep ) fiberglass bird, send it up low and slow, and do it at a launch where you'll have plenty of air & eyes.

Lucerne dry lake I'm sure the ceiling is around 15k

 

[billdz]

L2 certification special:
Level 2: Buy the reload and get the matching case free 38mm or 54mm (rear closure not included for 54, 75mm excluded)
https://www.offwegorocketry.com/pages.php?page=specials

 

[AfterBurners]

Afterburners,
You’ve been around quite a while. I commend you for not having rushed the experience.
With the experience you’ve gained, what appeals to you? What sounds fun?
You’ll do great. Enjoy!
My failed first attempt was the one thing I didn’t expect, motor retention using plastic hooks to hold the motor (dumb, I now know). I flew it a second flight (be sure to have a second motor) using masking tape retention.
(In my opinion) Only do things with the cert flight if you have experience with them and want to. So if you want to use electronics, get some experience using electronics in Level 1 flights first. Your goal is to certify safely.

Thanks Steve as always expert advice which I can trust from you. I remember we go way back to Rocketry Planet. Ideally a 4" upscale LexxJet? I'm sure some would love to see that fly, but as far as practicing with DD I was just thinking a small diameter rocket like a WM Wild Child? Not a big initial first investment and a good way to gain some experience with electronics. Awhile back I also read through cover to cover "Modern High Power Rocketry 2" but I would probably have to go back and re-read the section on L2 construction, certification and DD chapters. Great book and full of very valuable information.

Thanks again Steve!!

 

[AfterBurners]

I'm actually going thru this process myself right now. My L1 bird is built and sitting ready. I even have the motor. I've just been waiting for the weather to cooperate. Hopefully next Saturday is the day. In the meantime I've been researching and learning. Figuring out how to proceed towards L2.

My advice is to do something you want and find enjoyable. Don't cert just for the sake of certifying. So what kinds of things do you find interesting? Once you determine than then questions 1-5 can be answered better.

For me I am building a 3" Punisher. I wanted something that was durable and flexible. That could fly on baby H up thru full K and something that would allow me to step thru things and types of flying as I learned more. The Punisher fit the bill for me - 3" diamter fiberglass that's just about 5' long. I can fly it on a three grain H with motor deployment to 500' or a 6 grain K/baby L to almost 15k'. Those are two very different flights requiting totally different skills. So that's my 2 cents.

A couple words about working with fiberglass. A lot of people recommend washing all the parts in soapy warm water before you start assembly. I would add that you should take some 220 grit paper and knock the edge off of all the cut edges before washing the parts. A lot of the cuts have sharp fine bur's in my experience.

Lastly, good luck and I hope you get some great advice because I'll be following along and hopefully I can learn something too.

My reasons for L2 is not to get it to have it, but to expand my skills and grow into the hobby. I like the concept behind DD and being able to send a rocket up and above 5000 feet and walk less than a 1/4 mile to retrieve it, providing you can see the whole flight or someone can? You know what I mean?

Also as I mentioned my time is more limited now, but I still have the weekends most of the the time and I plan on taking some vacation days when I want to make a run at getting the build done so I have more options.

I took some time away from it so just glad to be back.

 

[jlabrasca]

A few things I would like to know are listed below, but please feel free to add to it and thank you again for your suggestions and input.

Thank You!!

AB

It will be interesting to see what kinds of responses you get. I went thorough a similar (but not matching) set of decisions when setting up for L2. This is how I made my choices.

1. Kit or scratch build - Kit suggestions?

Scratch build it -- just because. As others have said, and will say, do what you want. I scratched my L2 rocket(s) because I wanted to. As you say, time is always in short supply so it made more sense to fold some ideas I had about how to build a rocket, some materials I wanted to try, and some techniques I wanted to learn into the L2 attempt.​

2. Materials - If I choose fiberglass what are some of the safety precautions to follow when working with it?

On this one I will offer a straight-out, unqualified, opinion: use cardboard. It is strong enough for anything except for the hard landing which will fail the attempt anyway. As @dr wogz wisely observed in another thread "build it to fly, not to crash".​

3. Electronics - Altimeter suggestions?

Jolly Logic Chute Release.​

2 . Tracking devices - When do you determine a tracking device is necessary?

After you've lost a rocket over the horizon >smile<. Keep the rocket low enough that you can see it at apogee (see below) pack the smallest chute that will bring it down intact, use tracking powder, use a JLCR (see above), tie a long piece of surveyor's tape or a long strip of mylar to the shock cord, paint the rocket safety orange or fluorescent yellow...​

3 . Target Altitude - Whats a good altitude to shoot for?

This is the only one I think I can answer with math. But it is still conditional, How good is your eyesight? If you have pretty good visual acuity, and the day isn't too bright (or you are wearing quality aviator sunglasses), you can probably distinguish objects separated by as little as 50 arcseconds. For a 1 meter long rocket, that means you could see it -- as it noses over and is perpendicular to your line of sight -- at a distance of 4000 meters.

My L2 rocket was about 150 centimeters long and I sent it up on a motor that simmed apogee at 1300 meters. I blinked and lost it, but one of my sharp-eyed certifiers was able to keep it in sight all the way up and to see the deployment. I did not reacquire the rocket (as they say) until the chute release released.
​

4. Test Questions - I know there are questions on the NAR website, but how did most of you study? How did some of you study? Was it knowledge or memorize the Q&A

Memorization. Flash cards with the correct answers, and drilling right up until the day of the test. A few of the questions (too few) are things you can work out. A lot of the questions are about the rules for how far, how close, how much -- none of which can easily be figured out while you take the test.​

Good luck.

 

[David Schwantz]

Hey Afterburners, great that you want to get her done. Long story short, keep it simple. Keep it low, so you can see it. Keep it slow.
I like glass rockets, but still have many paper ones. Any LOC kit would be quality, just what ever may catch your eye.
Fiberglass, sand all edges, slivers suck. Wash and dry. Sand all glue areas with at least 60 grit, I like 36, I even go so far as to cross hatch with a burr in a dremel tool. You can tack parts in place with CA and then use epoxy of your choice. many good ones out there. This is where others will disagree, but I do not wear mask, and sure not a Tyvek suit. With all the glass work that I do I would spend hours getting dressed and undressed. And I've done it that way for 50 years. God, I'm old But to each his own. Sand the tubes with 100 grit to prep for paint. When drilling, do NOT force the bit through, it will splinter on the inside. You can even use a backing of small ply on the inside to stop the splinters. After holes are in, sand the ID, you can also bevel them with a larger bit by turning in hand slowly.
I like Eggtimers stuff, simple to use, and inexpensive. With that being said, the only electronics I would use on a cert flight would be a chute release. But again, my opinion.
Tracking, again Eggtimers are great, get a Mini GPS, will go in a very small tube.
Altitude, anything over 3000' I have a tracker in it. I also use Rocket Hunters, and they work great also. Or club rents them out. Do not know if you have that available.
Tripoli sends you the sample test and answers. Easy to study for like that. I do not know what NAR does. But if you need, at least I could email you mine.
Offwegorocketry is in my back yard, Gary is great. Will not go wrong with him. I took my L1 rocket over to his house and we went through it and he helped me choose a motor for my flight. Went perfect, could see the whole flight.
Please feel free to ask anything that I might be able to help with. Good luck. And after all this typing, I better see pics

 

[cbrarick]

build whatever you want. Have fun with it, whatever you choose. There is no correct answers for kit or scratch. If you're time is limited, kits go together quickly. Use whatever material you want. Electronics? I'm not a fan of chute releases, I'm a old fashioned altimeter guy, but that's my opinion. Do whatever you want, or don't. Tracking is a good idea with all rockets - I never fly without it. After all, trackers are cheaper then new rockets. Again JMHO. Altitude? Go for what ever you want. How do others fly at your club?? May be a good reference. Studying - I'm not a fan. I just took the test. It probably helps that I have a pretty much photographic memory, so do whatever worked for you in school.

bottom line, do what makes you feel good, after all, it's your cert not mine. Have fun with it. Don't become a slave to the "you gotta do it this way" school of thought.

good luck!

 

[MikeyDSlagle]

I used a paper kit for my L2, and a scratch build glass for my L1.
L1 used electronics with motor backup just to pop the chute at apogee, it went 1240 feet. L2 was full dual deployment with two altimeters. That rocket still flies with redundant electronics because they fit.

Any 4" paper kit of moderate length (not short stubby) will work fine. Madcow DX3 seems to be pretty popular. I used a Binder Design Tyrannosaur for my L2. Mike is responsive to emails, is very helpful and his kits are well designed and complete. Add a dual deploy package while you are shopping.

Many LOC kits fit the bill, all the way up to the likes of Mega Magg and Doorknob. A 5.5" V2 would be fun. Their customer service is on par with Binder.

Most definitely go with 54mm motor.

I think have developed a sensitivity to fiberglass so I don't build with it much, that and it's pricey and I'm cheap. But a long sleeve shirt, gloves, and some sort of respiratory protection if cutting, drilling, sanding, grinding.

If you have time to gather materials, or have stuff lying around to scratch build, that's great way as well. You can get just what you want, though it'll probably cost more.

L2 encompasses a large range of motors so there is a lot of variety. I'm not saying one rocket can't fly the entire range but one light enough for a baby J probably doesn't need to be flown on a full L, not by someone such as myself at least.

As for altitude:
My L1 bird is 2.6" diameter and about 4' long, painted black with yellow fins and polished. I have flown it to 1900+ feet and never lost sight.

My Tyrannosaur is emerald dark green metallic and black. It has gone to 6400+ on a K600 and I lost sight of it for a little while as passed by the sun on the way down, but it was easily visually tracked the entire flight.

The lower 2000s would be a good altitude to go for, heck maybe you'll even nail 2020!

I put an eggfinder in any rocket it'll fit in. Sometimes there is knee/waist deep vegetation, or freshly dug rows that are surprisingly good at hiding rockets.

Altimeters
I am slowly migrating to all Missileworks. The RRC2+ is cheap and easy and the RRC3 is a bit more high performance with more options. Jim has A++ customer service as well. I love the idea of the Quantum and Proton, and even like putting them together. However I had some issues during assembly of my Quantum and it never got resolved, which is one reason I haven't found the energy or time to start on the Proton.

 

[Steve Shannon]

Thanks Steve as always expert advice which I can trust from you. I remember we go way back to Rocketry Planet. Ideally a 4" upscale LexxJet? I'm sure some would love to see that fly, but as far as practicing with DD I was just thinking a small diameter rocket like a WM Wild Child? Not a big initial first investment and a good way to gain some experience with electronics. Awhile back I also read through cover to cover "Modern High Power Rocketry 2" but I would probably have to go back and re-read the section on L2 construction, certification and DD chapters. Great book and full of very valuable information.

Thanks again Steve!!

Wild Child would be a great L2 Rocket. The experience learning electronics and using Eggtimer products sounds very enjoyable too, satisfying on multiple levels. And it’s hard to beat the support that Cris provides.
Both NAR and Tripoli have study materials.
Coincidentally a week ago today I paid the server fees for Rocketry Planet’s we host even though it’s not published right now. Before he died Darrell asked me to keep it going. Someday I hope!

And if you’re ever at a launch where I am, please introduce yourself to me. I’ve got a lot of friends I’ve never met.

 

[wsume99]

My reasons for L2 is not to get it to have it, but to expand my skills and grow into the hobby. I like the concept behind DD and being able to send a rocket up and above 5000 feet and walk less than a 1/4 mile to retrieve it, providing you can see the whole flight or someone can? You know what I mean?

Also as I mentioned my time is more limited now, but I still have the weekends most of the the time and I plan on taking some vacation days when I want to make a run at getting the build done so I have more options.

I took some time away from it so just glad to be back.

I hope you didn't take my comments as assuming you were just going after the cert, I believed otherwise and you confirmed that. I was away for a while too because life got too busy and am getting back in again.

Most definitely go with 54mm motor.

1000% this!!! 54MMT for sure.

 

[AfterBurners]

I hope you didn't take my comments as assuming your were just going after the cert, I believed otherwise and you confirmed that. I was away for a while too because life got too busy and am getting back in again.

No not at all. It seems we are kind of are on the same page if anything. I took some time off (3 years) and now itching to do something different to get the sparks going again

1000% this!!! 54MMT for sure.

 

[AfterBurners]

I hope you didn't take my comments as assuming your were just going after the cert, I believed otherwise and you confirmed that. I was away for a while too because life got too busy and am getting back in again.



1000% this!!! 54MMT for sure.

Sorry looks like I answered that in wrong section by replying.

No not at all. It seems we are kind of are on the same page if anything. I took some time off (3 years) and now itching to do something different to get the sparks going again

 

[Arsenal78]

Keep it simple and low for a cert flight, something I wish I had done from the beginning. Trying again next month with a 5.5 LOC Goblin. Sims around 1800ft on a J425 DMS. Warlock is a nice one too.

 

[AfterBurners]

so I decided to go with the WM Wild Child. It's not expensive and WM offers a DD option for the kit. I just want to experiment with DD and figure this is a nominal investment to under stand the basic principles behind the concept. I don't want to invest in a bigger kit until I fell comfortable flying at this level. Anyway when I get ready to build I'll be asking for some advice and help I'm sure.

 

[AfterBurners]

Kit/scratch: whatever you prefer. There are lots of great kits out there or good experience to be had building scratch. Since you want to stretch yourself, a 54mm kit offers more room to grow than a 38mm kit. Simple and robust are good features.

Fiberglass: minimum half mask respirator with dust filters if you are dry cutting and sanding. That’s to keep you healthy. Long sleeves or a Tyvek suit and or barrier cream will help keep you less itchy.

Altimeters: I’m a fan of Eggfinder products and the Chute Release but they don’t float everyone’s boat. If you go redundant, you can have a small simple altimeter (Quark, RRC2+) and a recording altimeter (Quantum, RRC3, etc.).

Tracking: it’s hard to see a 4” rocket above about 5,000 feet. You can scale that altitude up or down by diameter or how good your eyes are. Definitely track if it’s out of sight and it’s not a bad idea any time.

Altitude: I just flew to what a small J took me to. It’s a good idea to keep it in sight if you can.

Test: I just committed the test questions to short term memory before taking the test and knew where to find info if I needed it later.

Discounts: some manufacturers have a very special where you get a free casing when you buy one or two loads. I just saw it advertised on AMW’s site but don’t know if anyone else is doing that now. Aerotech DMS loads are also a solid choice.

Any links to the mask respirator I should get? Just want to make sure I buy the right items.

Would this work?

https://pksafety.com/3m-6000-lead-a...t3yODRVs7Pc8uzQi0uGnx9egAVqhQIKxoCw6AQAvD_BwE

 

[boatgeek]

Any links to the mask respirator I should get? Just want to make sure I buy the right items.

Would this work?

https://pksafety.com/3m-6000-lead-and-asbestos-respirator-combination/?utm_source=google&utm_campaign=smart shopping all&utm_medium=ppc&utm_terms=&gclid=CjwKCAiAhJTyBRAvEiwAln2qB0y77eoHm2l1PrmrfhWeUKt3yODRVs7Pc8uzQi0uGnx9egAVqhQIKxoCw6AQAvD_BwE

That looks good for airborne dust, but @rharshberger is more up on respirators than I am. If he sees that I tagged him here, he might weigh in.

 

[Pariah Zero]

That looks good for airborne dust, but @rharshberger is more up on respirators than I am. If he sees that I tagged him here, he might weigh in.

That’ll do great for dust/particles - 99.97% of all particles down to 2μm.

You can also replace the filters with others- there’s a similar filter that will also filter out “nuisance odor.”

And, of course, there’s the organic vapor filters - they also filter out various fumes, including spray paint, acetone, alcohol, petroleum distillates, uncured epoxy/polyester, dirty diapers, SBD flatulence...

The nice thing is the half mask lets you swap out and use all of the filters.

 

[warnerr]

Love your attitude! Fiberglass would be my first choice: durability- the rocket must be in flyable condition to qualify. Standard recommendation is to do what you know: I get it. If only attaining a cert level this is the way to go. I prefer to stretch my knowledge- lots of opportunity in rockets, thats me, I have a go for it attitude with new concepts. Quality and knowledge matters and so far have not been let down. If you have a large clear area you may get away without tracking (4k feet needs tracking where i fly). Lucern, the birthplace of our hobby, does not need tracking at that altitude, as an example. motor deploy will get you a cert. Electronics will grow your knowledge. Choose wisely and always go with safety!

 

[AfterBurners]

That’ll do great for dust/particles - 99.97% of all particles down to 2μm.

You can also replace the filters with others- there’s a similar filter that will also filter out “nuisance odor.”

And, of course, there’s the organic vapor filters - they also filter out various fumes, including spray paint, acetone, alcohol, petroleum distillates, uncured epoxy/polyester, dirty diapers, SBD flatulence...

The nice thing is the half mask lets you swap out and use all of the filters.

You're absolutely right, but I just want to make I get the proper filters for the application. I don't want to be breathing fiber glass dust ...no thanks!

 

[AfterBurners]

Love your attitude! Fiberglass would be my first choice: durability- the rocket must be in flyable condition to qualify. Standard recommendation is to do what you know: I get it. If only attaining a cert level this is the way to go. I prefer to stretch my knowledge- lots of opportunity in rockets, thats me, I have a go for it attitude with new concepts. Quality and knowledge matters and so far have not been let down. If you have a large clear area you may get away without tracking (4k feet needs tracking where i fly). Lucern, the birthplace of our hobby, does not need tracking at that altitude, as an example. motor deploy will get you a cert. Electronics will grow your knowledge. Choose wisely and always go with safety!

Yes I'm doing this build not as an L2 but as knowledge that I can use for my L2 so I'm comfortable working with altimeters and building a sled and charge wells etc. I know my L2 doesn't have to be DD, but I feel DD opens up more opportunities and allows to fly higher with a better chance or recovery. For me I want to be challenged. I mean how 3FNC rockets can you build without getting stale? This is just my opinion and doesn't apply to all, because everyone has their own level of comfort, but sometimes its fun to try something new even if you fail, because you gain knowledge from the experience and you learn. So when the time comes to building this rocket I will definitely reach to the DD gurus for some advice and help.

I also plan on rereading the High Power Rocketry book again at least the section on L2 certification to get motivated and refresh my memory.

 

[Chris_H]

A consideration with fiberglass dust from sanding. The dust happens as it is being made, but unless it is captured at the source, as in, on a downdraft table, or equivalent, tiny dust particles will migrate throughout any indoor space where they are created. The tiniest, most damaging particle sizes do not really come out of suspension from the air. If you can, sand in a place that is ventilated directly to the outdoors. I have a powerful downdraft table, and massive hepa filtration units in my shop. I try to be as careful as I can with the really bad dusts, a category which fiberglass falls under. If you release a bunch of carbon fiber dust into your work area, un-contained, it will remain there, and be stirred into the air for a long time.

You can probably ignore all of this and sand away with minimal protection, but being safe with this stuff is a good idea, IMO.

 

[David Schwantz]

Hey After, the little dust mask with the pinchy nose piece will work for fiberglass, as long as you have a good fit. I use them almost weekly when I am loading cottonseed. That stuff will get in your eyes, nose and just about any other place you do not want to hear about. If you do use the mask with replaceable cartridges, you do not need the charcoal ones for that. But be warned, the charcoal ones will NOT keep you safe from some vapors. For that you need a pressurized fresh air supply, like this one. It was purchased from Hobby Air, got to be 20 years ago now, still going strong.

 

[Chris_H]

Yep, like this one. I have an extra that needs a little TLC, but a great pump and a ton of life left, that I would sell for a song. This exact model. I had 4 of these from a huge epoxy job many years ago. 2 left, and I only need one. Once you own one, you will use it for things that are way less noxious, just because it is comfortable, and works.


https://www.amazon.com/SAS-Safety-9800-32-Halfmask-Supplied-Air/dp/B000BHO1AW

 

[AfterBurners]

A consideration with fiberglass dust from sanding. The dust happens as it is being made, but unless it is captured at the source, as in, on a downdraft table, or equivalent, tiny dust particles will migrate throughout any indoor space where they are created. The tiniest, most damaging particle sizes do not really come out of suspension from the air. If you can, sand in a place that is ventilated directly to the outdoors. I have a powerful downdraft table, and massive hepa filtration units in my shop. I try to be as careful as I can with the really bad dusts, a category which fiberglass falls under. If you release a bunch of carbon fiber dust into your work area, un-contained, it will remain there, and be stirred into the air for a long time.

You can probably ignore all of this and sand away with minimal protection, but being safe with this stuff is a good idea, IMO.

It seems like working on fiber glass requires a great deal of attention to safety which I'm all for. Maybe I should stick with QT or card board only because I'm not familiar with fiberglass. I don't want particles hanging out in my work area. Although I can sand outside in the backyard I guess that would be fine?

 

[Chris_H]

Go with fiberglass.

Some people smoke a pack a day into their nineties.

If you can sand outdoors, do so. Sand in front of a door, indoors, with a fan sucking out. IMO, a little fiberglass is worth the cost. Be aware. Shower after sanding. Try not to touch your face or eyes.

Relish in the awesome rocket you build.

If you have compromised lungs, maybe stay away from glass.