Firing off my first rockets tomorrow....

[PharmrJohn]

OK....Got my Alpha III (I know everyone is jealous of this one.....SUPER rare.....oh yes) and the Liquidator ready to fly.

Now.....This is going to be a stupid question but here goes. The launch pad is something I got with the Alpha III. It seems big enough to accomodate the Liquidator (the rod), but the blast circle steel round thing-a-ma-bob doesn't seem large enough. There is hangover.....

I am presuming the guides are what counts, and as long as I do not stray over a D engine and keep aimed straight up, this will suffice.

Lord do I feel like a novice......

 

[powderburner]

Oooohhhh I just love that technical talk.

You mean the blast deflector? Yeah, the Estes disks can be kinda small but they are easy enough to replace. You can use a heavy-gauge scrap steel from around .040 on up to greater thicknesses. You are after something that won't burn through after only a dozen or so rocket motor exhaust impingements.

You can also use a cheapo floor tile (glazed or plain terra cotta, it doesn't matter) with a hole drilled in one side, they are available in sizes like 8x8 and 10x10 and even bigger, you ought to be able to find one that reaches underneath your rocket when placed on the pad.

 

[Gillard]

the pad that comes with the alpha will be fine for all A to C motors, if you want to fly Ds then you'll probably need to upgrade to a 5mm rod, which the estes pad will take. if you look at pad underneath the blast deflector plate (the metal disk) you can see that there are two holes, one is 3mm the other 5mm.
The pad will be fine, lots of people still use the estes pad even after they've built and flown hundreds of rockets. i have got 4 different pads and i still use the estes one if i want to fire off just one or two rockets.
You can do a couple of things to improve the basic pad set up.
use tent pegs to secure the legs into the ground will stop the pad tipping.
use a cloths peg on the rod to lift the rocket off the blast plate - makes it easier to contect the clips and prevents shorts across the metal plate - or buy a raise from odd'l rockets, they cost $1 well worth it. or even a blast from odd'l rockets $10.
the blast plate can be made bigger by slipping a circular cutting disk over the top.
once you move onto bigger rockets then you wil need a bigger pad, lots of people make their own out of camera tripods -but that's another post!

Hope you enjoy flying, take pictures and post them here.

 

[bob jablonski]

Another upgade is go to the nearest hardware store and buy a 1/8" rod made from steel. It is alot stiffer to cutdown on rod whip.
Mr. Bob
Starlight Model Rockets LLC
www.starlightrocketry.com

 

[MarkII]

The Alpha III is actually a very nice rocket. It was the very first E2X kit back in 1970, and it is still one of the very best. It has a very sturdy fin unit. The Alpha III Starter Set is an outrageously good deal. And I'm considering getting a Liquidator myself.

The blast deflector is large enough if it is able to deflect the jet from the rocket engine. It doesn't matter if the rest of the rocket extends beyond it, as long as the engine's nozzle is over it. The Liquidator is based on BT-60 (1.673" diameter), so the blast deflector of the Porta Pad II will work fine. But a couple of tips if you want to launch the Liquidator with a fair amount of liquid in the bottle: use some stiff bent wires (from wire coat hangers or use "garden staples") to stake the pad's legs down. With the weight of the water up there in the payload section, there is a slight risk that the pad could tip over, especially if there is also a breeze out at the field. Staking down the legs will prevent this. (If the ground where you live is frozen, then brace the legs with bricks or similar weights.) The other tip is to consider getting the 4' long 1/8" steel rod (cold rolled steel) that other posters have mentioned and using it instead of the Estes rod. The extra length will give the Liquidator extra help in getting stabilized when it is launched with a full load in the payload section. I don't know how much mass the Liquidator's bottle can hold, but getting this rod (and a 3/16" diameter one too, while you are at it) is a good idea anyway. But get steel, not brass; brass rods are way too flexy.

MarkII

 

[powderburner]

The other tip is to consider getting the 4' long 1/8" steel rod (cold rolled steel) that other posters have mentioned and using it instead of the Estes rod.

I agree with just about everything MarkII posted except..... I vote a BIG thumbs down on 1/8 inch diam launch rods in any length over 3 feet (and don't really like the 3 foot length if the model rocket is medium or heavy)

1/8 is handy, and will handle most small model rockets, but has too much flexibility ("whip") when using any longer sizes. Go with at least 3/16, or 1/4 inch if you can find it. You will need to swap up to bigger launch lug sizes.

 

[Pem Tech]

I agree with just about everything MarkII posted except..... I vote a BIG thumbs down on 1/8 inch diam launch rods in any length over 3 feet (and don't really like the 3 foot length if the model rocket is medium or heavy)

1/8 is handy, and will handle most small model rockets, but has too much flexibility ("whip") when using any longer sizes. Go with at least 3/16, or 1/4 inch if you can find it. You will need to swap up to bigger launch lug sizes.

I second the larger diameter launch rod idea. All our kits and my personal builds have 1/4" LL's on them. Of course, I haven't tried that on a Micro Maxx kit yet, but we will see.

 

[MarkII]

I agree with just about everything MarkII posted except..... I vote a BIG thumbs down on 1/8 inch diam launch rods in any length over 3 feet (and don't really like the 3 foot length if the model rocket is medium or heavy)

1/8 is handy, and will handle most small model rockets, but has too much flexibility ("whip") when using any longer sizes. Go with at least 3/16, or 1/4 inch if you can find it. You will need to swap up to bigger launch lug sizes.

Of course thicker rods are better, but that won't help if his Liquidator has 1/8" lugs. My recommendation was specific to that rocket, and you may not have noticed, but I did also suggest that he get a 3/16" rod, too. Layne, if he is just starting out now with an Alpha III, it will probably be awhile before he needs a 1/4" rod. Heck, I've been doing this for 5 years and I'm only starting to need one now. I could be wrong, but I suspect that he won't want to jump ahead to launching 3" diameter, 5' long rockets on G motors just yet. We use 4' x 1/8" steel rods in our club's launch pads without any rod whip issues. Our launch site tends to have a pretty steady breeze, and the longer rods help us get straighter flights that stay in the field. I agree that if a rocket is causing a 1/8" rod to sway, it is obvious that it needs a thicker rod. The OP can certainly get a 3' rod if he wants to as well. The Estes rod is 30" long. If a 1/8" x 36" long steel rod isn't rigid enough for launching low power rockets on A-C motors, then what do you suggest he use in place of his Estes rod for his rockets that have 1/8" lugs?

I guess that a 1/8" x 36" long piece of music wire would be better, but he would have to get that either online or from a hobby shop. My recommended material, cold-rolled steel, is available at any hardware store and is plenty stiff enough; it's what I use. I get mine out of the standard structural rod section of the hardware store, not the welding rod section. Perhaps that explains the difference; a similarly-sized length of annealed welding rod might indeed lack the necessary stiffness. I did advise against using brass rod because it is about as stiff as a guitar string. Aluminum rod smaller than 1/4" in diameter is also too flexible (if he could even find any). The best choice would probably be 316 stainless steel rod; it isn't expensive but it is hard to find locally. Surprisingly, even titanium rod in that diameter is not absurdly expensive; it will never tarnish and will last forever.

A good source for such rods is Onlinemetals.com.

1/8" diameter Type 316L stainless steel rod.
1/8" diameter tool steel rod. (Another very rigid material)
1/8" diameter 6Al-4V titanium rod.

MarkII

 

[MarkII]

I second the larger diameter launch rod idea. All our kits and my personal builds have 1/4" LL's on them. Of course, I haven't tried that on a Micro Maxx kit yet, but we will see.

The lug would be as large as the motor! In fact, you can use FlisKits Micromaxx motor tubing (BT-2.5) for 1/4" launch lugs. A 1/8" diameter launch rod looks enormous when it is held up next to a Micromaxx launch rod (0.049" dia.).

MarkII

 

[powderburner]

Of course thicker rods are better, but that won't help if his Liquidator has 1/8" lugs.

That is certainly correct, and for right now, he's kinda stuck.

He could shave off the outer 3/4 of the existing LLs and glue some 3/16 lugs into the "saddles", but then you have re-painting or else it looks like doooky, and if you paint then you have a chance of ruining the decals, and it's more trouble, and it's probably not worth it

Also, it is likely that 8 or 9 times out of 10, he will be able to launch just fine using a 3 foot, 1/8 inch diam rod, even for a relatively large modroc like a Liquidator. But (PharmrJohn, this part is directed to you) if you want to have the flexibility to be able to launch slightly heavier modrocs safely, or if you want the capability to continue launching on slightly windier days, you need to step up to a bigger launch rod diameter. This will have significantly less motion or whipping and will get your rockets off to a straighter flight. Larger rod diameters also work better if you want to use lengths greater than 3 feet, which also helps your rockets off to straighter flights. Even if you only increase to a 4 foot length, it will make a difference. Order a supply of 3/16 LLs and keep them around for replacements, because most of the manufacturers seem to automatically go to the 1/8 size.

I hope you guys will excuse my conservatism, it's just that I recently finished helping in a legal matter where a kid was nearly killed---and my evaluation of the cause of the mishap was rod-whip (with aggravating circumstances). This is just so blankety-blank easy to eliminate that I am now a BIG pusher of solid launcher setups. Launch rod size is a poor place to skimp on launcher safety features. This is one place where I feel that bigger is indeed better, especially for beginners, who don't understand the physics (or don't even have the training to begin understanding), or cannot recognize marginal wind conditions, or who don't build their modrocs with "perfect" fin alignment and balance, or don't have an experienced advisor present. Keep in mind that the 1/8 inch size was selected way back in the day when modrocs as a whole were MUCH smaller and lighter (C motors were the biggest thing available), the problems of rod-whip were not well understood (or even experienced yet), and a certain company that sold modroc supplies primarily by mailorder had to consider shipping weight and cost. Now we have bigger modrocs, and while they can still work on 1/8 rods, it would be good to change to something bigger at the earliest convenient point---in my opinion.

And I still agree with everything else you posted.

 

[follr]

I bought an starter kit with the porta pad II also. I have launched all my stuff including the estes eliminator on a D. I haven't had issues with any of them. I do recommend weighting the legs down with a brick or rock, but for your first launch you will be fine.

Just go launch and have fun. Don't get all rolled up in mods yet. Trust me you'll get just as addicted as the rest of us then you'll be looking through the board for any mod you can do to get bigger and bigger rockets off the ground.

The blast deflector is used to protect the ground under the launch pad. If the ground under the pad is dry grassy area then consider moving to another area but you should be fine. I just slide an old 10" tile/paver blade on top of the estes blast deflector. It adds a little more weight too.

 

[RocketsNorth]

You have a good starter set with the Alpha III.
My son and I started out last year with it and have had many fine launches.

We lost our original Alpha last Spring and I bought a replacement we like it so much.

The pad & controller have never given us a problem even launching motors up to D12's. You will need to go for a bigger controller the Estes E or other when you get into clusters or multiple motor rockets down the road.

 

[dcastle]

You have a good starter set with the Alpha III.
My son and I started out last year with it and have had many fine launches.

We lost our original Alpha last Spring and I bought a replacement we like it so much.

The pad & controller have never given us a problem even launching motors up to D12's. You will need to go for a bigger controller the Estes E or other when you get into clusters or multiple motor rockets down the road.

-----

The Alpha III was my first rocket, in a starter set, that I received for Christmas 1972. What a great flier that was....even though my very first flight, in January '73 in front of my 6th grade science class, was a CATO...37 years later I'm still into rockets...

Wore out the original Alpha and it's long since gone. But I have a red and white one right here waiting to fly sometime soon.

 

[Solomoriah]

Get a 6" ceramic tile (under 50 cents around here) and a small diameter masonry bit, and very carefully drill a hole in the center. Voila! A bigger blast deflector that won't short your clips.

 

[Fred22]

Get a 6" ceramic tile (under 50 cents around here) and a small diameter masonry bit, and very carefully drill a hole in the center. Voila! A bigger blast deflector that won't short your clips.

That sounds like a great idea
Cheers
fred

 

[Solomoriah]

Yeah, I love my ceramic blast deflectors... mine cost me all of $0.39 each. I recommend putting a piece of wood under the tile when drilling it, and I had the best luck drilling from back to front.

 

[UPscaler]

OK....Got my Alpha III (I know everyone is jealous of this one.....SUPER rare.....oh yes) and the Liquidator ready to fly.

Now.....This is going to be a stupid question but here goes. The launch pad is something I got with the Alpha III. It seems big enough to accomodate the Liquidator (the rod), but the blast circle steel round thing-a-ma-bob doesn't seem large enough. There is hangover.....

I am presuming the guides are what counts, and as long as I do not stray over a D engine and keep aimed straight up, this will suffice.

Lord do I feel like a novice......

The estes deflector should be fine. For my pad I took the deflector off the Aerotech mantis pad and built around it with PVC. Good stuff!

 

[PharmrJohn]

Thank you all for your replies. The weather turned and we still haven't launched......it has been weeks now since Christmas!!! But patience is a virtue, I have to remember............