HARM Missile

OH BOY!

I get to start a thread in the High Power section of the forum.

This is the beginnings of Carl's new L3 HARM project.

Saturday I got this big package in the mail with a section of 7.4" PML tube and a tube coupler.

I glued up the foam and attached a plywood plate to the bottom so I could fit this really big chunk of foam to my lathe.

The plan is (if it works) to turn the correct profile for the nose out of foam isulation and cover it with 2 layers of fiberglass cloth.

I will finish the fiberglass with West System epoxy (that's all I will ever use), finish sand and prime it, then sand it again. This can all be done while the nose cone is still on the lathe.

Just to prove that you can turn a big foam nose cone on a lathe...and to freak out Carl. I've included a pic.

Boy, I can't wait 'til Carl sees this!!! hehehehehehehe!

sandman

That thing's huge! I take it we gave up on the maple idea then?

Sandman,

Just curious, are doing this to instigate a project or are you working with Carl to help him out?

Jeez...that thing is HUGE!!!!!!!!!! I can't wait to see the rest of the rocket that is going with it.

I just like making round things from square things.

Maple was kinda expensive, especially if I messed it up. $6.00 worth of foam is enough to make 3 of these things.

The dust from the turning is actually a lot better than wood. All the dust falls straight down while maple sawdust floats in the air long enough for you to breathe most of it into your lungs.

This has been suprisingly easy to do so far. I want to wait before the final turning 'cause ya really gotta concentrate on the last part so I get the dimesions just right.

I have to allow for the added fiberglass on the body tube.

More later.

sandman

<h2><b>O - M - G !</h2></b>

That looks frigg'in GREAT Sandman...gawd I can't believe you started on it already man...guess the cat is outta the bag, huh?!

Yea guys, you got it...I have designed one of my two winter projects and have requested the services of master woodcrafter, Sandman, for the nosecone work. Originally, it was to be designed and cut on a lathe out of wood, either Maple or Basswood. However, he feels very good about trying his hand at making one from glass, and I say have at it!

OK, here is the project for those with inquiring minds:

AGM-88A HARM Missile
True Scale - 75%
Length - 123"
Diameter - 7.5"
Dry Weight - 53lbs
Motors - M1600 - N2000

That is all for now...

Carl

how about an N4800!!!! hehehe

whats the M1600? is that one of those cool AMW motors that will probably never see CSFM approval? I sure wish I had a lathe to make my 7.5" scale ogive V2 nosecoune out of...... the whole wood skeleton -> expanding foam -> rough shape -> sand and fill to shape -> fiberglass -> sand, fill, prime thing took FOREVER!

-Brian Barney

the M1600 is the redline load for the 98/7680 case.

Not to burst anyones bubble, but AT is not looking very good right now... They just laid off half of their remaining workforce, and I'm hearing that Clark County may be suing AT for something to do with the Fire last year...negligence maybe...

Ron

I'm sure most bubbles won't be bursted until the source of the story is confirmed.

I just got my 1st 29/40-120 RMS casing today. Please don't rain on my parade.

If indeed this is true, please furnish the source it came from. In the meantime, imma gonna builda a big rocket.

Originally posted by AZ_Ron
Not to burst anyones bubble, but AT is not looking very good right now... They just laid off half of their remaining workforce, and I'm hearing that Clark County may be suing AT for something to do with the Fire last year...negligence maybe...

Ron

Click to expand...

I really can't say who I heard it from, but it was also being discussed on the ROL conferencing chat room tonight.
It's not slowing me down any, then again, I don't fly AT stuff either... there are other manufacturers on the market... I don't think AT is going away, but I think this may hamper their re-emergence.... I don't wish Gary and AT any harm...they've done more to promote and grow this hobby than anyone, but I think Clark County is going to use them as an example...

Ron

https://www.lvrj.com/lvrj_home/2002/Aug-10-Sat-2002/news/19383713.html

With any luck, AT will be up and running before any charges are filed. If I read this correctly, it looks like if anything is done, it will be a criminal lawsuit and not a civil one, which is bad if you're the guy being indited, but good in that the company won't have to shell out millions. That being said, the fire chief sure sounds like he's going to encourage his men to fire civil suits, although he'd be silly to do so, as it sounds like the county could also wind up a defendant in that case.

OK guys...progress report!

This took me about an hour...needs fine tuning but I left it kinda thick. I will make it slightly undersized so it has room for two layers of fiberglass and epoxy.

I am also going to try my hand at vacuum bagging.

She will get a nice thick coat of epoxy too so I have room to make it nice and smoooooooth!

This stuff is really easy to work! Pink foam.

sandman

Lookin' sweet! Please, when you document with pics, show me how you fiberglass a complex curved structure like that. I can picture how you do it to a cone, but not an ogive like that.

Sandman...

Frigg'in fantastic looking, bro!!! You have the touch...can't wait to see it with clothes on...

Kermie, if you cut your cloth so the weave is at a 45 degree angle, it will easily "accordian" and allow you to push, pull and nearly form it to any surface.

Carl

Had to add this...did anyone notice Sand's shop is even more organized than mine...all his tools lined up in rows, bottles perfect...and this is a woodwork shop, which makes that tough to do! Gawd, I knew I like him for a reason!!!

Dude, he's as sick as you! I thought I'd never see the day.

Dudes,

I didn't organize the shop!

My anal retentive brother-in-law came over one Saturday when I wasn't home and spent eight hours organizing (even the trash!).

Usually you can't even walk through there.

sandman

Originally posted by sandman
Dudes,

I didn't organize the shop!

My anal retentive brother-in-law came over one Saturday when I wasn't home and spent eight hours organizing (even the trash!).

Usually you can't even walk through there.

sandman

Click to expand...

Yeah, it was my brother-in-law... that's it... it wasn't me... really... I'm normal... I'm not like Carl at all

Enough with the organized jokes! The rest of my shop looks like a TRAIN WRECK!

I did screw up the profile but I cut the nose cone in half and am adding another 4" section in the middle to fix it. (making it longer and I will turn it again.)

This is still an experiment in turning foam. MAN! is this stuff easy to work with!

It's very easy to fix mistakes. I do have to wait 'till the glue dries so it is on hold 'till tomorrow.

I have also been experimenting with different types of glues to use on the foam. BTW don't use Elmer's carpenter glue...doesn't seem to dry and is awfully hard...you get ridges on the seams.

Any suggestions would be appreciated. I was considering using Great Stuff foam as a glue...

So far Gorrilla wood glue seems to work the best...kinda foams up too! but it is expensive.

Don't worry, Carl, it's gonna be purdy!

sandman

Sand...you definitely got me excited...so much that I bought a 2' x 2' x 1/2" thick piece of Birch Ply and am starting on another deploy unit for the HARM.

I have it designed so the Rocket could use the one from the Amraam, but I decided, heaven forbid, should I ever have a problem and core sample one of these birds...I would still have two or three L3 rockets left without a deploy unit...so I am making a spare. Total cost...$12, but still need some all thread and hardware.

As far as gluing foam, I have had great luck with "Super 3M 77" Contact Spray Adhesive. Spray both pieces...let em get so they are nearly dry and not tacky...slap em together and they should never come apart again.

BTW...how is the drawing working out?

Carl

She's ready for fiberglass!

A little filling, get everything together, have a nice cup of coffee, take the phone off the hook and break out the West System 'cause...

WE'RE HAVIN' A FIBERGLASS SESSION TOMORROW!!!

I'm pumped!

sandman

sure, you have to go and temperarily clutter up part of the garage and have the picture taken at a different angle to show that you aren't like Carl

Don't worry about em razz'in you about your shop Sand...I now realize that I am alone in this unorganized world...all you regulars and me with my gal Abby......Abby-Normal that is Long live anal retentive organization!

Damn Sandman, that last pic was pretty sweet!!! It appears that you have outdone yourself so far, way to go...It looks like it has the profile it needs and you look like you are having WAY too much fun... Very cool!

Looking forward to this weekend's glassing spree...

Carl

Well, since Sandman has been keeping busy on the nosecone, I figured it was time for me to start play ( a much better word to use than work) on the deployment unit. I had mentioned I spent around $17 for the entire assembly, minus some all-thread rod and hardware.

I went shopping yesterday and got the 3/8" all-thread Rod, some U-Bolts and some brushed steel handles. Note that all the hardware is Stainless Steel, which helps prevent corrosion. I began by drawing out the ten disks needed to make the cylinders for the deploy unit. I also took time and drew out a faceplate for the unit. The remaining Ply will be used to make the three 7.5" Centering Rings and the 7.5" Bulkhead plate I will need for the unit.

I inventoried all the parts I had from an Excel Spreadsheet I created and everything was there. Most of the hardware and some parts I already had, which made this a much less expensive endeavour. Next, I began by sanding one end of a 3.9" diameter PML Phenolic Body Tube, then measured and cut it to near a length of 13.5". The center fins for the rocket are 12" long at the root, so it followed the exact same dimentional profile as the Amraam and will make this deploy unit easy to construct. Finally, body tube was fine sanded on the cut end and the deployment unit from my Amraam fit inside this tube just right.

Not much in the way of pics yet, but here are a few:

https://www.rocketryforum.com/ctulanko/album/?dir=harm

Cya,

Carl

Ya know, this sandman/tulanko collaboration is scarin' me. Tulanko, the fact that your last post was at 2:30 in the morning did not escape me, either.

Let me guess, you want to have this all finished and ready to launch on Monday, right?

Guys, don't forget, this is only supposed to be a scale model.... not the REAL THING -

Seriously - sandman, you better be careful or people will be trying to get you to start a custom fiberglass nose cone business - What I am seeing in the pics looks great.

Oh, and Carl - you passed Abby-Normal a Loooong time ago. Hell, you passed obsessive-compulsive a Looong time ago...

but don't neglect to keep posting pics. For the last two months, the only way I have been able to enjoy the hobby has been vicariously through this forum. I'm really just jealous and having withdrawal sypmtoms.

Originally posted by CTulanko
I inventoried all the parts I had from an Excel Spreadsheet I created and everything was there.

Click to expand...

Spreadsheets now? AIIIEEE!! All hope is lost!!!! I'm with Ken here. Abby is wayyy to good for you these days.

Most of the hardware and some parts I already had, which made this a much less expensive endeavour.

Carl

Click to expand...

Yeah. When you own your own hobby shop you can buy your parts from, it helps too.

After getting a few lessons on warp, wafe and the other properties of cloth from my wife, I now have two layers of fiberglass on the nose.

Monday after the epoxy has cured a bit and is still 'green" I will start the lathe again. (The nose cone is still on the lathe and it sure made it easier to put the cloth on.) and give it a cleanup sanding with 80 grit.

Finally, 4 or 5 more coats of epoxy to cover up the weave and let it cure fully for about a week.

Heck, I even had time to help my neigbor install a sliding glass patio door this morning.

I think I'll take Labor Day off.

Sorry no pics...the fiberglass doesn't show up on my cheap digital camera...it would just look like the pic from last night.

sandman

Originally posted by CTulanko


Not much in the way of pics yet, but here are a few:

https://www.rocketryforum.com/ctulanko/album/?dir=harm

Cya,

Carl

Click to expand...

Carl, you really need to get yourself a drill press and circle cutter to make your centering rings. Your sanding down method looks VERY time consuming..... with the circle cutter, you just measure it out, then test on some scrap stuff, and once you have it to the right diameter, you can pump them out in no time flat!

-Brian Barney

Believe it or not, the sanding method works really well, but is very un-reliable, as the ring may end up out of round. Lathes work well to get a perfect, acurate circle, as well as the method that Brian recommended.

BTW> Carl, make sure that you clean out the sanding disk, it will work much better if you do!!!

Well guys, I had some fun today building the parts for the deployment unit. I took the ply sheet to work with me and at lunch time, cut out the small plates and face plate, then drew out the four 7.5" CR's/Bulkheads. Whe I got home, the Small plates were split apart, then shaped. I drilled centering holes where the protractor left it's mark, then bolted all 10 plates together and fine sanded them on the belt sander.

Brian, sanding the plates by hand actually doesn't take all that much time, although a circle cutter would be handy. I do have a drill press; it along with my bench sander are my two best tools to have in my shop and I used them like crazy when building my L3 cert rocket. I don't mind spending the time sanding and I actually use the belt like a lathe, so Dan...got it covered.

The 7.5" plates were cut and fine edge sanded, and now need 3.9" holes in them...now I could use the circle cutter, but couldn't find one earlier this week.

More tomorrow...I am tired,

Carl

Oh yea...pics are up--> https://www.rocketryforum.com/ctulanko/album/?dir=harm