First HPR scratch build, Tank Girl

stickershock23 said:

Well if you like big rockets.....


tank girl ROCKS LOL

Oh and I hope thats not too out of line... sorry if it is.

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I saw that one, but didn't think it would be appropriate for all audiences. LOL

accooper said:

We need more rocket babes. the car guys have them, why don't we?

Andrew

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Sounds like a rallying cry to me! My nephew built Miss Fortune, but she crashed. :sad:

He really needs to rebuild it.

I think it would fly great on a pair of E30's.

o1d_dude said:

He really needs to rebuild it.

I think it would fly great on a pair of E30's.

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Yeah, I got him a new nose cone for it, but he hasn't gotten around to working on it. He's been having life difficulties.

qquake2k said:

Sounds like a rallying cry to me! My nephew built Miss Fortune, but she crashed. :sad:

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I`ve always been a big fan of "Vargas Dame art" , nothing finer in my opinion.Ask any B-17 ,B-25 or any of the other great bombers that sported nose art.

Gorgeous !

Paul T (did a BA in fine art)

I got the recovery cable made today, and the retention clips fabricated. The cable is 3/32", and the clips are made from 1/8" x 1/2" aluminum. I also weighed her. With retention and all the recovery gear, but without motor, she weighs 66.3 ounces.

4lbs and change??? Are you sure? I figured she was good for least 8-10 with you building her. I think all the grief I give you is having an impact. She oughta fly good. Way to go.

El Cheapo said:

4lbs and change??? Are you sure? I figured she was good for least 8-10 with you building her. I think all the grief I give you is having an impact. She oughta fly good. Way to go.

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Hey, I didn't do anything different this time to save weight. I used my usual copious quantities of epoxy, and in fact, I used thicker plywood for the fins. I used 1/4" plywood for the centering rings and baffles, and a 1/4" u-bolt for the recovery attachment. Frankly, I'm a little surprised at her weight, too. I hope she doesn't go to high and/or too fast!

I'm debating on which motor to use for her first flight. I'm thinking either a CTI H123 Skidmark, which will take her to around 1000 ft. Or an AT H170 Metalstorm, which will take her to around 1400 ft. I'll probably buy both reloads, and let the wind on the day of the launch be the deciding factor.

I mixed up some epoxy putty and put it inside where I'll drill for the upper rail button.

Huh? It is black and orange? I thought it was green and orange.

eggplant said:

Huh? It is black and orange? I thought it was green and orange.

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You mean the rocket colors? It's green, black, and red.

Is the aft end black? It looked green in the other pictures. I guess what I think of as orange is red.

qquake2k said:

Great minds think alike! I'd love to see a photo of your DX-3.

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Here ya go Jim ,my DX-3 in "our" favorite colors

Paul T

eggplant said:

Is the aft end black? It looked green in the other pictures. I guess what I think of as orange is red.

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The entire body is dark green, it just looked black because the photo was dark. This photo is a little brighter.

sodmeister said:

Here ya go Jim ,my DX-3 in "our" favorite colors

Paul T

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Very nice! I love the roll patterns.

Thanks for clearing that up!

I drilled through the hardened epoxy clay for the upper rail button. I decided to tap it just in case. Worked like a charm. I had already drilled into the plywood block for the lower rail button, and I tapped it as well. She's ready to fly. All I need is a launchsite. That's going to be the hardest part of this build - waiting until November to fly her.

I'm looking forward to seeing this bad girl fly, too.

Maybe with a little luck we'll be able to launch in October.

o1d_dude said:

I'm looking forward to seeing this bad girl fly, too.

Maybe with a little luck we'll be able to launch in October.

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Well, we can't fly high power at SARG (except for cert flights), and LUNAR doesn't have a scheduled Snow Ranch launch in October. So to launch her before November, I'd have to go to Fresno, and I'm not sure I want to do that again.

qquake2k said:

Well, thank you for the compliments! I put the baffle plates about 3/8" apart. But I put mine in the top of the motor tube, not the coupler. I do put a baffle in the coupler of my zipperless designs, but I also put the half moons in the motor tube underneath it.

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I cut the baffle plates today with my circle cutter,also made my top plate of the baffle for the eyebolt.What's the tested strength of the eyebolt you would use?My rocket is BTH70 body tubes and 51 inched long,it weighs 14.7 oz.I was at Lowes and saw a 3/16 x 2" eyebolt and almost bought it.As I was walking to the front to pay for it,I noticed it was rated at 40 lbs.I'm concerned it would not be strong enough.All the other eyebolts looked to large and might add to much weight.What should I look for when shopping for a eyebolt?

cjp said:

I cut the baffle plates today with my circle cutter,also made my top plate of the baffle for the eyebolt.What's the tested strength of the eyebolt you would use?My rocket is BTH70 body tubes and 51 inched long,it weighs 14.7 oz.I was at Lowes and saw a 3/16 x 2" eyebolt and almost bought it.As I was walking to the front to pay for it,I noticed it was rated at 40 lbs.I'm concerned it would not be strong enough.All the other eyebolts looked to large and might add to much weight.What should I look for when shopping for a eyebolt?

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I use 1/4" eyebolts in my MPR scratch builds. I always cut off the extra length to lighten it. It will add at most an ounce or so. The photos are of 1/4" eyebolts in a BT70 coupler.

Is that 40lbs the working load or breaking load? The breaking load is usually a lot higher. I have a 3/16" eyebolt in my 3" Hijacker, which I've launched on up to a G80. It did get a zipper, but the eyebolt didn't fail. It weighs 18oz, and the baffle is cardboard.

qquake2k said:

Is that 40lbs the working load or breaking load? The breaking load is usually a lot higher. I have a 3/16" eyebolt in my 3" Hijacker, which I've launched on up to a G80. It did get a zipper, but the eyebolt didn't fail. It weighs 18oz, and the baffle is cardboard.

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I'm not sure,I saw 40 lb. on the tag.I might take a close look at the 1/4" eyebolt.That one had 80 lb. on it's tag.I thought it looked to large.I asked about the load rating,I told him what I needed it for,but he really couldn't help me.

cjp said:

I'm not sure,I saw 40 lb. on the tag.I might take a close look at the 1/4" eyebolt.That one had 80 lb. on it's tag.I thought it looked to large.I asked about the load rating,I told him what I needed it for,but he really couldn't help me.

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Honestly, for such a light rocket, I think a 3/16" eyebolt will be fine.

qquake2k said:

Honestly, for such a light rocket, I think a 3/16" eyebolt will be fine.

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I have been looking for forged eyebolts on the internet and see all are 1/4" and 500# rated.I just might go with 3/16" or the 1/4" that is rated 80#.I have all my baffle plates sized and ready to install.My BTH70 is a 2.267" OD.you put 8 holes in your top plate,with mine and it's size,do you have any recommendations on the number of holes and size of drill bit I might go with?

cjp said:

I have been looking for forged eyebolts on the internet and see all are 1/4" and 500# rated.I just might go with 3/16" or the 1/4" that is rated 80#.I have all my baffle plates sized and ready to install.My BTH70 is a 2.267" OD.you put 8 holes in your top plate,with mine and it's size,do you have any recommendations on the number of holes and size of drill bit I might go with?

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I tried out a couple drill bits and decided to go with 11/64 and here's what I came up with on my 1/8" plywood plate.Do you think the holes are large enough?

cjp said:

I tried out a couple drill bits and decided to go with 11/64 and here's what I came up with on my 1/8" plywood plate.Do you think the holes are large enough?

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I drilled 1/4" holes in my BT70 baffle. I think I'd go a little bigger than 11/64".

qquake2k said:

I drilled 1/4" holes in my BT70 baffle. I think I'd go a little bigger than 11/64".

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As this is my first attempt at this type of baffle I have many questions(sorry).I'll go 1/4" and see what happens.This is only 1/8 plywood.Thanks again.cjp.

cjp said:

As this is my first attempt at this type of baffle I have many questions(sorry).I'll go 1/4" and see what happens.This is only 1/8 plywood.Thanks again.cjp.

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This is an 1/8" baffle for a 3" coupler with 5/16" holes. I think yours with 1/4" holes will be fine. And don't be sorry about your questions, ask as many as you want. I or someone else will answer all we can. That's how we learn!

qquake2k said:

This is an 1/8" baffle for a 3" coupler with 5/16" holes. I think yours with 1/4" holes will be fine. And don't be sorry about your questions, ask as many as you want. I or someone else will answer all we can. That's how we learn!

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I went with 1/4" holes but around the holes the wood chipped away.It looks like you have fender washers on yours,is this to provide strenght?I worry that the wood will slip because of the jagged holes.I will post a picture of mine later.