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gary7

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Want a new launch rod and looking at 1/4 inch x 6ft in the following:

aluminum
cold rolled steel
stainless steel

I think the aluminum may whip a bit with a 3# rocket or will it otherwise be stable enough?
Will the stainless steel be slicker that the plain steel? It is almost 2x the money but still only about $10 here locally.

Is there a way to lubricate rods to promote better lift off speed etc?
 

Micromeister

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Want a new launch rod and looking at 1/4 inch x 6ft in the following:

aluminum
cold rolled steel
stainless steel

I think the aluminum may whip a bit with a 3# rocket or will it otherwise be stable enough?
Will the stainless steel be slicker that the plain steel? It is almost 2x the money but still only about $10 here locally.

Is there a way to lubricate rods to promote better lift off speed etc?
I strongly suggest going with 1/4" x 72" 316 alloy Stainless Steel. 303/304 Stainless is OK but the added molybdenum in 316 alloy give it higher corrosion resistance and mechanical properties at elevated temps.
With Stainless (either alloy) cleanup and maintenance is a snap. just wipe down with fantastic and spray with a little WD-40 it'll last a very long time. If you get APCP burns you don't like a little white vineger on a rag takes it right off.
Hope this helps.
 

n5wd

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Want a new launch rod and looking at 1/4 inch x 6ft in the following:

aluminum
cold rolled steel
stainless steel

I think the aluminum may whip a bit with a 3# rocket or will it otherwise be stable enough?
Will the stainless steel be slicker that the plain steel? It is almost 2x the money but still only about $10 here locally.

Is there a way to lubricate rods to promote better lift off speed etc?

The stainless is easier to keep clean and rust-free. I've occassionally had to take some fine sandpaper to our steel rods - nothing that a little elbow grease won't cure, but I'll buy stainless steel next time. We use either WD40 or silicone spray on the rods - the spray won't give you better liftoff speeds, but will help to prevent the lugs from getting hung up.

Haven't had any experience with aluminum, but I'd think they'd be too wimpy.
 

plano-doug

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Haven't had any experience with aluminum, but I'd think they'd be too wimpy.
One caveat of aluminum is that, when cleaning it with sandpaper, you can gall it pretty easily. That said, I've gotten good use of my 1/4"x4' aluminum rod.



Doug
 

plano-doug

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Want a new launch rod and looking at 1/4 inch x 6ft ...
6' is a good length for 1/4" rods, but you want to find someone to machine it so you can disassemble it into two 3' sections. And that can be difficult. Some form of steel is best for this, so that rules out aluminum. The downside is that any imperfection in the alignment of the end bore for the tapping will result in a step when the two sections are screwed together. A little bump is tolerable, but ideally, there isn't any - you don't want to scrub off vital momentum while accelerating up the rod. We've had machinists complain about the difficulty of getting the alignment, so I know it's a real problem, but I'm also sure it can be handled if you find the right person.

Keep in mind that if you leave the rod at 6', it will surely get bent. At that length, you will constantly be finding it difficult to put in the car :)

Doug

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gary7

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Keep in mind that if you leave the rod at 6', it will surely get bent. At that length, you will constantly be finding it difficult to put in the car :)
I have not considered it bending. I think it would be rather easy to store it in a piece of pvc or something.

At any rate, I have decided on the stainless steel.
 

MarkII

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Carrying 6' long launch rods in a car shouldn't present any problems. I have done it many times. I have driven home from the hardware store with 10' lengths of PVC pipe carried inside my Kia Optima.

MarkII
 

plano-doug

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Carrying 6' long launch rods in a car shouldn't present any problems. I have done it many times. I have driven home from the hardware store with 10' lengths of PVC pipe carried inside my Kia Optima.
Mark,

You can do it. But it's a PITA. I carry my 4' and under rods in a PVC pipe. For them, I open the trunk and throw them in. It's a snap.

For a 6' rod, I agree you can protect it from bending with a PVC case, but every time you open the car, you gotta lean in, fold down the rear seat, then slide it in. There's always that extra overhead, and eventually, most folks will get in a hurry, and the result is a bent rod.

We can all put up with a little inconvenience. But for some of us, after a while, it gets tiresome enough that we don't want to put up with it anymore. So we find a machinist to make the rod into two pieces :)

Doug

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MarkII

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Oh, I wasn't talking about protecting the rod in a PVC case, although that IS an excellent idea. I just mentioned the 10 foot sections as an example of just how long of an object I can get into it. I just fold down half of the split rear seat. Then I insert the length into the trunk, slide it forward past the folded down seat back, and if necessary, keep it going up into the front passenger seat. For the 10 footers, I have the back end of the piece in the rear left corner of the trunk, and the forward end up in the passenger seat, resting on the dash. :D I don't need to fold down the front passenger seatback; the object either simply goes over the top of the seat or it fits in between the two front seats. I carry my 8 foot launch rail that way, too. Folding one half of the rear seatback down is a piece of cake. No bending or reaching needed. I just reach in from one of the rear doors, press a release button on top of the seatback next to the head rest, and then pull the back down. I can also slip a 6 foot rod into the back seat diagonally and fit it up between the two front seats.

As long as you don't jam it up against anything or have anything lay on it, I don't see how putting a launch rod into the car will get it bent. Placing it inside a case made from PVC pipe, a couple of slip-fit threaded couplers (glued on) and a couple of threaded end caps will provide even more protection. None of my launch rods have ever been bent even a tiny bit, even when I carried them inside the car.

I have been carrying them this way for years. It simply has never occurred to me to have someone make a rod that could be separated into two pieces, mainly because I never felt the need for something like that.

MarkII
 
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ScrapDaddy

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Want a new launch rod and looking at 1/4 inch x 6ft in the following:

aluminum
cold rolled steel
stainless steel

I think the aluminum may whip a bit with a 3# rocket or will it otherwise be stable enough?
Will the stainless steel be slicker that the plain steel? It is almost 2x the money but still only about $10 here locally.

Is there a way to lubricate rods to promote better lift off speed etc?
aluminum is a very poor choise it is wimpy even with the little suckers that I fly
 

Micromeister

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Have to say Doug:
Car damage is generally Not the problem, Most of the 1/4" and larger x 6 and 8 foot one piece stainless steel Launch rods I've sold, used and observed over the last 3 or 4 decades get bent by not so bright folks during model loading or being stepped on be kids. Riding in the car is the least place a rod or rail will get abused.

I do suggest making a very inexpensive PVC rod storage container you just suggested. they take only about 10 minutes to put together and take all the fight out of keeping your long and short rods safe, clean and straight. 1-1/2" or 2" diameter PVC, plain and screw plug coupling and cap can be had at just about any home improvement center.

PS: I carry my perosnal 6' and 8' rods & rails etc. in an old 6' x 5" McMaster-Carr Mailing tube.

Launch Rod storage Tube-a-sm_Attach to Rack rearview_08-05.jpg
 
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Evo666

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I guess I'll head back to the hardware store for some pvc. You guys always come up with so many things.
 

Evo666

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I just went to pick up 1/8, 3/16 SS rods for $5 at Online Metals. If anybody wants the 5% off, pm me before it expires in a month.
 
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