Ye Olde Rocket Forum

Go Back   Ye Olde Rocket Forum > Work Bench > Building Techniques
User Name
Password
Auctions Register FAQ Members List Calendar Today's Posts Search Mark Forums Read


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 10-14-2006, 07:55 AM
bikegod bikegod is offline
slave to the wind
 
Join Date: Mar 2006
Location: Fredericksburg VA
Posts: 101
Default RMS questions (again)

After waiting for what seems like forever for a 24mm engine, I ended up with an 18mm housing as well. I of course ordered 1 set of charges for it and being as it was an unexpected boon, decided to practice loading on it instead of my 24.

Maybe I am dense, but the instructions didnt' seem quite clear to me. I expected the load to just slip in. I also didn't realize that the ejection charge was in the little red caps that came with it. I spilled it all over my workbench but was able to scoop it all back in.

Lastly, the copperhead igniter, looks like one piece of metal. Where do I connect two leads to it to cause the igniter to ignite?

I had never intended to get the 18mm, and I still haven't loaded the 24. I am quite afraid of igniting this thing for fear of an unexpected explosion. Mostly because I really had to convince that charge to slip in. Once I had it part of the way I couldn't pull it out so I forged on ahead. None of the charges in the 3-pak fit any better. Some of the cardboard sleeve got distended and I ended up trimming it off.

Before I load up the 24, can anyone chime in on their (recent) experiences with the 18? Could I possibly have a bad casing or loads?

Bike
Reply With Quote
  #2  
Old 10-14-2006, 10:29 PM
ghrocketman's Avatar
ghrocketman ghrocketman is offline
President, MAYHEM AGITATORS, Inc.
 
Join Date: Jul 2005
Location: Nunya Bizznuss, Michigan
Posts: 13,443
Default

One often has to "coax" the propellant grains into ANY/ALL of the RMS cases, be it hobby line (18/20, 24/40, and 29/40-120) or the various 29-38-54-75-98mm HPR RMS cases. Often one has to peel part of the cardboard liner off the propellant grain to get it into the case. You are NOT experiencing anything abnormal.
Many new RMS users expect it to be a "Wham-Bam & you are done" experience in building RMS loads. It sometimes can be, but it is usually NOT so.
Some use a thin layer of "O-ring" grease on the outside liner of the propellant grain to get it into the casing also.
The key to RMS is in taking your time and following the directions EXACTLY.
If you don't follow the directions exactly the result is often a CATO !
When using copperheads, the easiest way is to use the special Aerotech "interlock" igniter clip, which is designed for them. The copperhead actually has two leads that are separated by a fine layer of plastic. It is a copper-plastic-copper sandwich. I use a lighter on the non-pyrogen coated end to melt the plastic....the two halves of copper curl away from each other...then one can use regular micro-clips.
When using copperheads (or ANY igniters for composite-propellant engines) you ABSOLUTELY CANNOT use a 4AA cell Estes-type "Electron Beam" controller to fire them....it WILL NOT RELIABLY WORK !
You MUST use a 12V car-battery power source type controller such as the Aerotech Interlock controller or the old Estes ASTRON launch controller. I personally have both & use both. One can also build their own 12V controller if they have the electrical experience.
__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL
, if you have to ask what is "NORMAL" , you probably aren't !

Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !
Reply With Quote
  #3  
Old 10-14-2006, 11:05 PM
bikegod bikegod is offline
slave to the wind
 
Join Date: Mar 2006
Location: Fredericksburg VA
Posts: 101
Default

Thanks, I knew someone out there would alleviate my fears.

The 18 seems jammed in there, but the 24mm with E11s went just fine. In fact I almost forgot to grease it as I was test fitting the parts it just started to go together. Before I got to the ejection charge though I went back and lubed it up in just the right places.

Concerning the 18 though, I lubed up the case, the charge and o-rings etc. I still am not sure what I plan on sacrificing to it (all of my 18mm rockets may be way overpowered by th D-13 loads).

Concerning the ingition: Cigarette lighter adapter and say 25' or more of lead to microclips. What do you think? My ignition would be plugging it into the lighter socket, with the failsafe of the car must be turned on for the lighter to have power. I have three sockets in my PT and two are keyed (won't come on without being in at least accessory postition).

Tomorrow (if I can get my electronics together) may see the maiden flight of my SLS-Laser. I am only planning an E-18 for first flight. Based on RockSim, I should see about 1000' (though with the amount of paint and filler I have on it, I am only hopeful of the first 5 or 6 hundred). I really considered an E11, but my RockSim doesn't have that engine on file and I haven't been able to get the Engine Edit to work right for me yet. I used an E-12jrc for the numbers but don't trust them.

Sorry to be so chatty about RMSs and the like, but SLS models and RMS engines are so new to me. I first, don't want to kill/hurt/ or otherwise ruin anyone's day, and second, don't want to blow up my beautiful rocket (which, by the way, has probably 40 hours worth of sanding/refinishing on it). Not bragging, but I have never spent this much time or care on anything so far. It has been quite rewarding and I hopefully have learned some patience and how not to depend on shortcuts.

I plan on getting some decent photo's of it before I light it up. I am quite proud of my fillets (thanks to SkyPirate's instructional) and the finishing details (thanks to all of you here) and last but not least thanks to Carl@Semroc for the awesome kit in the first place. If she my first RMS experience, I may ask for the 29mm engine mount (I glued in the 24mm adapter) and try some larger engines and loads.

Wish me luck tomorrow. Sunny and 61 here, ist the forecast for Sunday. As long as the breeze isn't too high, you may see my launch report here as well.
Reply With Quote
  #4  
Old 10-14-2006, 11:35 PM
CPMcGraw's Avatar
CPMcGraw CPMcGraw is offline
BARCLONE Rocketry
 
Join Date: Mar 2005
Location: Mobile, Alabama
Posts: 5,357
Default

Quote:
Originally Posted by bikegod
...Concerning the ingition: Cigarette lighter adapter and say 25' or more of lead to microclips. What do you think? My ignition would be plugging it into the lighter socket, with the failsafe of the car must be turned on for the lighter to have power. I have three sockets in my PT and two are keyed (won't come on without being in at least accessory postition).


If you can find one of the earlier BLUE-PLASTIC Electron Beam controllers, these were assembled with screws instead of being heat-welded together. You can add an extra set of wires connecting to the internal battery terminals that run to either that cig port plug, OR get some heavier-duty gater-grabbers and some 14-gauge zip chord, and have all the convienience of a regular controller with the oomph of a 12V car battery instead of the 6V from four AA's. Just swap out the 6V bulb with a 12V bulb, and you're set. Swap out the remaining 20' of lead wire with more 14-gauge zip chord and you should be able to handle up to three-motor clusters without a Chernobyl...
__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635
Reply With Quote
  #5  
Old 10-14-2006, 11:47 PM
bikegod bikegod is offline
slave to the wind
 
Join Date: Mar 2006
Location: Fredericksburg VA
Posts: 101
Default

I actually have one of the Blue Ebeam controllers. I got it with an old kit from Wally World years ago (sat in my closet till this year and pulled it out when I was off my feet, and soon became Born Again).

I thought it was defective when the light wouldn't come on. I emailed estes and they sent me the yellow controller (still in the package to this day). While fooling with the blue one, I connected an igniter to it with 4AAs and tested it. Of course it worked, and I ended up with two controllers.

I'll hit Radio Shack tomorrow and get my supplies. Now I won't need micro clips! Hate soldering anyhow. BTW, would two 9Vs work (if I can't get my car close enough to the field)? Or what about a garden tractor battery? I think they are 12V also (but I am not sure).

Thanks for the idea. Even though it is almost 1 here, I am going to pull my controller out and check it out now!

Later: Color me bummed, but the original Ebeam controller I have is black and welded shut, however, the new yellow one has two little screws in the bottom of it. The launch key seems to be MIA, but it looked the same as the other one that is still attached to the black controller. What a deal!

My original kit (Code red, 3 engines, pad and controller) set my Father in Law back almost $15 3-4 years ago. Who would've thunk I'd be doing this now.

I kick myself for letting it sit in the closet for so long.
Reply With Quote
  #6  
Old 10-15-2006, 12:03 AM
CPMcGraw's Avatar
CPMcGraw CPMcGraw is offline
BARCLONE Rocketry
 
Join Date: Mar 2005
Location: Mobile, Alabama
Posts: 5,357
Default

Quote:
Originally Posted by bikegod
Later: Color me bummed, but the original Ebeam controller I have is black and welded shut, however, the new yellow one has two little screws in the bottom of it. The launch key seems to be MIA, but it looked the same as the other one that is still attached to the black controller. What a deal!


I have a black controller with screws...

Most of the late-model controllers are heat-welded, but mine is several years old and came with an Astrocam 110 Starter Set.

The oldest launch keys from the Solar Controller would work, too...
__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump



All times are GMT -5. The time now is 12:52 AM.


Powered by: vBulletin Version 3.0.7
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Ye Olde Rocket Shoppe © 1998-2024