Yepf

YET ANOTHER PERFECT FLIGHT

WAHOO!
Yesterday was another perfect flight from Thunder N Lightning. Flown on an I300 to a H123. Reached 4263' at about 360 mp/h. It was spectacular. I absolutely love this rocket and so does eveyone else at the club. Along with my two stage flight another person flew his MiniBBX and Terrier on an H242 to a G80. And someone else attempted a two stage flight with an I200 (?Ceseroni?) to "something." The "something" never lit though. A friend I was helping prepare for his two-stage flight, also a MinBBX and Terrier, chose to wait until next month but flew just the MiniBBX on an I200 for a spectacular flight to 3000'.

The only problem I am having with T&L is cleaning it. When the H123 lit, the exhaust turned the upper part of the booster gray. Does anyone know anything that would remove this discoloration without taking off the paint or gloss finish?

I also have one question for anyone who has used Mirage paint. I didn't want to start a seperate thread for just this one question:
Has anyone had problems with mirage paint softening NC's at all? (Just something I heard this weekend)

David

Mirage paint softening nose cones??? That wouldn't make sense at all. I don't know about the plastic nose cones but that fiberglass one that I did is perfect. And I would expect plastic would do well too. I made sure to prime it good though...

Congrats on the T&L launch! Where are the pics?

I used Mirage paint on my SHX-15 modroc. It has a much thinner nosecone than any HPR rocket (as you'd expect). I detected no softening.

Conrats on a successful staged flight...very cool!

Mav.... you're probably going to think I'm crazy, but as for removing the exhaust residue from your booster rocket, try..... vinegar. Yep, good ole white vinegar that you get at the grocery store.

Congrats on your second staged flight. Sounds like you have it down pat.

- Ken

Ok, thanks for the opinion on the NC subject. I didn't think it would but I figured I should ask.

I believe that vinegar would work. Actually, I was just thinking that. Unfortunately, I'll have to wait until mom gets to the grocery store cause I used the last of the vinegar cleaning my reload casings last night.

Here is another question for you guys though: Have you guys had any problems with black, charred pieces of stuff in the threads of your reload casings? In the case that had the I300 this weekend, the threads became locked (had to use vise and wrench to take off closures), there appears to be some gas leakage at the forward closure because the outside of the forward end of the case is discolored (as well as the inside), and there is this rock-hard black stuff in the threads that just won't come out. Any ideas? (This hasn't happened to me before but I have also never used this reload before)

Yes, I would like to think that I have got the staging stuff down, but if I do, and get cocky about it, I'm sure I'll screw up, so for now, I'm just a modest beginner.

As far as pics go: There is only one on the NEPRA website. Here is the link to page with the day's pics. T&L is down toward the bottom. These are only a few of the flights(129) from the day, of course.
June 8th Pics
I couldn't get any pics because I was LCOing with dad when it went up. If anymore pop-up though, I'll let you know.

Dave

hmmmm... haven't really had anything like what you are talking about with the black charred pieces in the threads of reload casings. If vinegar isn't getting them clean enough, there is a "next step." Get some Hoppes #9, which is used to clean guns. You can get it at Wal-Mart, K-Mart, lots of places. It's somewhat stronger than vinegar. You might also need to get an old toothbrush to help with cleaning the threads. Or, you might even need to get a new toothbrush, with extra firm bristles.

I haven't used the particular reload that you are talking about, so I have no idea if it is a consistent characteristic of that reload.

Along with a toothbrush, you might want to look at getting a baby bottle brush for cleaning as well.

It has a long skinny brush to get inside the casing, plus a smaller more pointed stiff brush for the forward closure.

Ok, I have some gun cleaner. (Yes, I also shoot- skeet and I am on the Rifle team). I will use that and see how it comes out. Unfortunately, I doubt it will work. I have tried a lot of things. These include: Acetone, Mineral Spirits, lava soap, water, vinegar, xylene. If the gun cleaner doesn't work then I'll get out the exacto knife and try to pop it out of the grooves. It is still usable, but I would like to get the hardware clean so I don't get more locking-up of the threads on future flights. I have not used a large Blue Thunder I reload before so it may be a characteristic of it, I don't know.
Also, do you guys have some pinkish discoloration in your reload hardware? I have it where the o-rings usually sit and where the phenolic insulator tube cracked on this last flight with the I300?

Dave

Did you use any lubricant during the assembly of the motor?

If not, that may be the reason why there appears to have been gas leakage and the resulting deposits of waste materials on and in the threads of the closures and casing.

A light coat of petroleum jelly, on the threads of each closure, as well as the outside of the grain liner and all of the "o" rings, is better than nothing. It helps make a better seal and will make cleaning much easier.

Yeah, I did use some vaseline. Just like normal. I have not had this problem before. The 38/240 casing that had the sustainer H123 in it came out fine (no black pieces). Maybe a little pinkish discoloration around where the o-rings usually go, but other than that it is fine. I just don't know anymore . Oh well, at least Eclipse's mirage paint id coming out good, really kewl

Dave

Arggh! The vinegar (picked it up last night) didn't remove the exhaust from T&L. Any other suggestions guys?

I haven't gotten to trying the gun cleaner. First I have to run over to the local woodworking shop up the street and pick up an allen wrench for the screws for the altimeter bay. (And it is hot out)

Dave

Dave,

Here's my method of cleaning cases and closures. It's never failed for me.

1. Immediately after recovery use a wood dowel to force the liner and any propellant residue out of the case. I then use a dentist's "pick" to pull out the insulator and O=ring from the delay well.

2. Wipe every thing off with a "Baby Wipe" and set aside unless you need to use the case again for that launch.

3. Take a small shallow plastic pan and place the casing and closures in it being careful that they do not touch. Cover them with white vinegar and let them soak at least one hour, preferably overnight. OBTW the reason for the plastic container and keeping the parts separate is to prevent electrolysis from degrading the anodizing on the casing and closures.

4. After soaking for at least one hour take the cases and closures out and scrub at any remaining desposits with a firm bristled tooth brush.

5. If deposits still remain use a good gun cleaner like Hoppe's #9 and cotton patches to work on the deposits. If you know someone with a wood lathe try to get them to make you a set of wooden cleaning rods made to fit the size cases you are cleaning. Take a look at the rods used to clean pistols for an example. The head of the rod should be a couple thousands of an inch smaller than the inside of the case so that you can push a cotton patch through with it.

Also in general the better lube you use on your reloadable cases, and the tighter you screw in the closures, the smaller the chance of even partial "blow by". I highly recommend either DOW 111 high temperature grease, which can be obtained from McMaster-Carr, or the high temperature grease sold by Radio Shack. Either of them will keep working under higher pressures and temperatures than vaseline.

OBTW I have seen the liner on a Blue Thunder engine split, but have not seen any external signs of it reflected on the motor casing or closures. The flyer who showed me the split liner had used DOW 111 to grease the O-rings and closure threads, however.

Ken Holloway, NAR #78336, L-1

Wow, thanx for the in-depth explanation. I hadn't thought of picking up any high temp. grease. Everyone I know just uses petroleum jelly (I think). The problem may have been just not using enough grease. I usually don't use much because I am so careful about not getting any on the delay grain. My ways may change though.
As far as the dowel, right now I have a cylinderical scrub brush that seems to work well. It gets out everything except whats in the threads. For that I use an old, stiff toothbrush. I may consider this but for now I think I'll stick w/ what I got.
I usually go through about the same process that you described. Unfortunately, I don't get time at launches to clean my motor casings while I'm there (I usually try helping out, LCOing w/ dad, setting up pads, helping others, etc...). So, when I get home I clean them first thing, most times. At this past launch I was tired and waited until the next day...bad decision .
AFA the split liner goes, I guess that just happens on occasion.
BTW- I got to using the gun cleaner yesterday and it got out almost all of the remaining junk. Thanx for that suggestion

Dave

Dave,

That Hoppes #9 works wonders, doesn't it! As far as the grease goes Aerotech recommends high temperature grease with PTFE. I ran some samples through the test lab at the Nuclear plant I work at and it turns out that what they supply in those little plastic tubes with their "Hobby Line" casings is identicle with the grease sold by Radio Shack. The DOW 111 was a tip from a friend with over 10 years experience in the hobby. His advice always seems to work out.

Ken

Ken,
Nuclear plant? OOOOOH! Me like

Hmmm? ...a reload casing, some 4FG BP, a bunch of 98mm slugs of AP, some C-4, a little magnesium for that special glow, some gun powder for a little more kick, a couple of grams of weapons grade plutonium (I'll give u a call), and a partridge in a pear tree..."Z" motor anyone?...I mean...nevermind
(Just joking of course)

All right, sounds like its time for a trip to radioshak. Figures, I just came from there, oh well, yet another chance to gawk at there electronics.
Thanx

Dave

Ken,
Do u remember about hom much the grease from Radioshack costs?

Dave

Mav,

I have to concur that the Radio Shack stuff is great! I have been using it exclusively lately with excellent results. Also, the local Lowes or Home Depot also has a lube that is the exact same as Aerotech...Ken Parker told me about it. I used this stuff on a M1419W and, during cleanup, the liner pushed out easily by hand, then I just "wiped" off the lube inside the tube...this stuff is a godsend!!!

Carl

Price: between $2.99 - $4.99...don't quite remember, but it was cheap considering...

Dave,

The Radio Shack grease is $4.95 for a tube large enough for one or two seasons of flying. The Dow 111 from McMaster-Carr is $9.99 and is better than the RS stuff. We use DOW 111 here at the Perry Nuclear Plant to grease the moving parts of valves which run at 400 to 550 degrees. I'm going to switch over to it once I've used up the tube of RS grease I have now.

Of couse it helps that I won't have to pay for it. We buy it in 55 gallon drums and there's at least a 1/2 a pound of the stuff left in them when they're returned to the warehouse by Plant Maintenance.

Ken