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Jun 19, 2009, 03:52 PM
Team Swallow
Jonas M.'s Avatar
Thread OP
Yippee!

Make your own Booms - The Video


Hey Guys,

I thought I should share a complete boom roll.

I got everything from Dave Hill's awesome How-To. I just put the camera next to my workbench and tried to show you every step.

My layup is quite a bit different from Dave's. I don't use the small FG strip but just overlap the two pieces of carbonfiber. I also added two strips of 80g/mē/2.5oz unidirectional CF (orientated perpendicular to the boom's length) to gain more "hoop stiffness" - the result is great!

I use the light carbon only on the front 2/3 of the boom. The aft part is harder to compress anyway, due to same wall thickness but smaller diameter.

I'd like to thank Dave Hill for his help, without the tutorial I wouldn't be able to make such a boom!

(7 min 25 sec)


(9 min 30 sec)


Greetings,

Jonas
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Jun 19, 2009, 04:27 PM
Jeff Carr
Jonas

Thanks for posting the video. It will make an attempt very easy

Jeff
Jun 19, 2009, 04:28 PM
BANNED!!!
soholingo's Avatar
Thanks for sharing Jonas. That is very informative...

Jay
Jun 19, 2009, 05:22 PM
Registered User
raed5's Avatar

Thanks for sharing


I have read Dave's "how to" watching it on video makes sense of it all.
Thanks Jonas.
Raed
Jun 19, 2009, 05:25 PM
Walter Roos
ROOSWH's Avatar

Thanks Jonas, and thanks again Dave


I've been putting off making my booms, thinking I needed more room to work, etc. etc. Now you leave me without a good excuse to jump right in.

Thanks, Great Video,

walt
Jun 19, 2009, 05:25 PM
Team Swallow
Jonas M.'s Avatar
Thread OP
Thanks for your comments.

Makes me think it was worth the effort to make a video ...

Jonas
Jun 19, 2009, 06:05 PM
Fossilator
danfield's Avatar
Jonas

Nicely done, I really enjoyed that. I bet that was not your first one, I would have to think about it longer than it took you to make one. :-)

A number of little tricks easier to be seen than explained.

I went back and looked and didn't see the width you cut the cloth at but I guess that would depend on the shaft someone got a hold of to use for the mandrel.

You said "Over-Lap 6mm's both" .. I couldn't quite tell but I assume since they seemed to be the same width it was an Offset of 6 mm's or shifted sideways is all. Must make a nicer seam or none at all.

I have seen only a few other Pictorials of how to, no one seems to think dropping into a Vac Bag might be even better, or just not necessary?

Regards
Dan
Jun 19, 2009, 06:27 PM
Team Swallow
Jonas M.'s Avatar
Thread OP
Dan,

the actual overlap is 6mm. Dave's layup uses a small glass strip to join both CF layers. I put the 8020 CF, that goes on the mandrel first, UNDER the UD carbon. When rolling the carbon onto the mandrel the 8020 CF lifts the other carbon from the waxpaper.

This way you get a slightly noticeble seam where more than two layers are. When installing the boom on your plane you put the seam at the 3 or 9 o'clock position, depending on left or right handed thrower.

The width of the carbon cloth is simply diameter x pi + 6mm.

One special thing I learned from Dave is not to blot too much. You WANT to have a certain amount of resin in your layup, otherwise the result is a weak boom that will fail at the compression side because the fibers can't hold together.

Jonas
Jun 19, 2009, 10:30 PM
wishes this caption was longe
will_newton's Avatar
nice Jonas. I hope folks will realize now that they have seen the video that it's not rocket science to make a tailboom!
Jun 19, 2009, 11:13 PM
Registered User
Shaper Dave's Avatar
Jonas,

Nicely done and in such a small space! This should be added to my thread so its a package deal for everyones use.
Cool,

Dave
Jun 19, 2009, 11:22 PM
Walter Roos
ROOSWH's Avatar

Work Space


Thought you guys might like to see Jonas' set up space behind where he is standing.:
Jun 20, 2009, 03:33 AM
Team Swallow
Jonas M.'s Avatar
Thread OP
Guys, I know I have to clean up my workspace

Also I would like to hear your opinion on my current layup. Is it wise to put the light carbon only on the front 2/3?

Jonas
Jun 20, 2009, 08:07 AM
wishes this caption was longe
will_newton's Avatar
Jonas, your layup looks fine to me. There was some discussion of putting extra carbon in the big end of the boom in the "Stiffer Booms" thread. Your weight is comparable to the weights I get on similar layups- It's actually a bit lighter since you have a bit lighter weight fabric.

Your techniques are very similar to the way I do mine (modeled on Dave's work as well). I do a few things differently, not that they are better, just different:

1.When cutting the fabric, I lay down the cardboard template, then place a long ruler beside it, pick up the cardboard and cut the fabric with an exacto using the ruler as a guide. It's goes very quickly.

2. I use a foam roller to distribute the epoxy rather than a squeegee. I like your sponge idea for putting down the epoxy.

3. I just mist the 80/20 with some 3M77 before I cut the pattern out and don't bother with wax paper carriers. It stays together fine.

4. I like the toilet paper to get up the extra epoxy. Much more efficient to use than paper towels, which are bit large. I get a similar amount of epoxy out of my layups. There is some transfer, but the paper doesn't feel wet and releases from the carbon without sticking.

5. I have never bothered with wiping the squeezed out epoxy from the mandrel layup. It comes off OK. Also, you can try leaving the boom in the drill jig and just loosening the chuck, grab the end of the mylar and just peel it off as the mandrel spins freely. I have also started removing my mandrel from the jig after laying up and hanging it vertically overnight, just to make sure it's straight as I can get it.

6. To get the tape out of the inside, I get the small end of the boom tape loose and attach a thin dowel to it with sticky tape. I then drop the dowel down the inside of the boom until it comes out the big end and start pulling the tape out. The VCR tape seems to come off easier when removed this way.

Again, your video is great. Maybe Shaper Dave has a few comments as well. I think it would be great for you to post a link in his boom rolling thread to this thread, or just reposting the video in it.
Jun 20, 2009, 09:14 AM
Team Swallow
Jonas M.'s Avatar
Thread OP
Hey Will,

Foam rollers are way too expensive here, especially since they are used only one time.

My video tape may be a bit old, so it doesn't release that easy. Even at the slightest drop of epoxy it tears. Just unrolling it while in the jig doesn't work for me.

How does the sticky tape grab the tape? Mine is full of vaseline and wouldn't stick to anything.

Jonas
Jun 20, 2009, 09:29 AM
Red Merle ALES VII SJ
Curtis Suter's Avatar
Jonas,

Awesome work and great video, easy to watch and learn.

Thanks for posting.

Curtis
Spangdahlem AB Germany 1986-1992
Bitte Ein Bit!


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