New scratch build, X-Plane SST

o1d_dude · Dec 16, 2012

Finally a 54 mm motor tube. It's about time.

Fist thing: Might want to hold off on populating your Av-bay until your get your chops up on dual-deploy because you may decided to do things differently this go around.

Second thing: Check that you will be able to fit a quick-link down into the U-bolt when the motor mount is installed in the body tube. With my 4" Squat and the 54mm motor tube, I couldn't make the u-bolt fit and ended up using a forged eyebolt set at an angle.

qquake2k · Dec 16, 2012

sodmeister said:
Oh ,I hear you LOL

I need a lathe ,but nothing too big ,perhaps this year.

Paul T

I've heard a lot of good things about the Jet Mini.

https://www.amazon.com/dp/B000MIR9JA/?tag=skimlinks_replacement-20

Or there's the Harbor Freight version. Mine is a bigger Harbor Freight, and I haven't had any problems with it.

https://www.harborfreight.com/5-speed-bench-top-wood-lathe-65345.html

qquake2k · Dec 16, 2012

o1d_dude said:
Finally a 54 mm motor tube. It's about time.

Fist thing: Might want to hold off on populating your Av-bay until your get your chops up on dual-deploy because you may decided to do things differently this go around.

Second thing: Check that you will be able to fit a quick-link down into the U-bolt when the motor mount is installed in the body tube. With my 4" Squat and the 54mm motor tube, I couldn't make the u-bolt fit and ended up using a forged eyebolt set at an angle.

Oh man, am I glad you said something! I would have bet you cash money a 1/4" quick link would fit on it, but sure enough, when it's in the body tube there's not enough clearance. It is oh so close, but no cigar. A 3/16" quick link will fit, though, and has a 616lbs working load vs. 880lbs for the 1/4". I thought about putting a welded ring on it, but a 1/4" ring only has a 200lb working load. I thought about making a steel cable for it, but I don't know what kind of load rating that would have. I could also make a new centering ring and put a slightly larger 1/4" u-bolt in it. I haven't decided what I'm going to do yet.

qquake2k · Dec 16, 2012

Got the blocks and tee-nuts epoxied to the centering rings, and sanded the blocks flush. I also got the fin patterns cut out and taped together.

o1d_dude · Dec 16, 2012

IIRC a 3/16" stainless steel quick link has a working load of 800 lbs or so. Pretty close to a standard 1/4" one.

Here's my Skwat 54mm motor mount. Notice how the eye is mounted at an angle for clearance. Also, I used your method of adding thickness to the centering ring to mount the rail buttons.

chadrog · Dec 16, 2012

qquake2k said:
Got the blocks and tee-nuts epoxied to the centering rings, and sanded the blocks flush. I also got the fin patterns cut out and taped together.

Love the fin design, looks menacing.:dark:

qquake2k · Dec 17, 2012

o1d_dude said:
IIRC a 3/16" stainless steel quick link has a working load of 800 lbs or so. Pretty close to a standard 1/4" one.

I didn't think about stainless. I bet they have stainless u-bolts, too.

o1d_dude · Dec 17, 2012

Yes they do. I buy stainless hardware from Lowe's and Home Depot but I know where to look for it in the places I frequent.

For some reason Lowe's seems to have a wider selection. My store has it on the shelf with the Stanley gate hardware and fittings rather than with the fasteners. YMMV.

Spooks · Dec 17, 2012

This is gonna be SWEET Jim!!!!

I tell ya, I flew my L2 flight on a 54mm...you can FEEL it fly!!

You are gonna have an awesome build going here and I can't wait to see it fly...

Now, since I can buy BIGGER motors now, I need to come up with something too!! :grin:

qquake2k · Dec 17, 2012

I picked up a stainless u-bolt and 3/16" quick link. And while it probably wasn't necessary, I was afraid drilling another hole for the wider u-bolt would weaken the centering ring. So I made a new one, this time from 3/8" plywood.

CarVac · Dec 17, 2012

If the centering ring isn't necessary to transfer thrust (only doing actual centering) then there is no need for anything but lateral compressive strength.

qquake2k · Dec 17, 2012

My Black & Decker bullet point drill bits are getting dull, especially the ones I use a lot. They don't make them anymore, so I looked at the DeWalt pilot point bits. But just 1/4" and a 5/16" replacement bits were $13. This set was $20. The math worked for me. I don't care who you are, that's a sexy drill bit, right there!

qquake2k · Dec 17, 2012

CarVac said:
If the centering ring isn't necessary to transfer thrust (only doing actual centering) then there is no need for anything but lateral compressive strength.

Well, there will only be two centering rings, so I would think they'd both transfer thrust. Besides, I'm paranoid. I might throw a high thrust motor in this some day.

qquake2k · Dec 17, 2012

I got the new wider stainless u-bolt fitted to the new centering ring. I had to modify the backing plate a bit to make it fit.

qquake2k · Dec 17, 2012

As you can see, the new u-bolt is considerably wider. Because of the extra width, both the 3/16" and 1/4" quick links now fit.

qquake2k · Dec 17, 2012

Anybody need a brand new never used custom made 1/4" centering ring with a small pre-installed u-bolt? I'll even autograph it for you! :tongue:

MasonH · Dec 17, 2012

I like this build. I like it a lot. Keep it up!

qquake2k · Dec 17, 2012

MasonH said:
I like this build. I like it a lot. Keep it up!

Well, thanks, Mason!

qquake2k · Dec 17, 2012

I got the rail button block (I need to come up with a better name for this) epoxied to the new centering ring, and sanded flush.

qquake2k · Dec 20, 2012

Finally got a little more done. I epoxied the forward centering ring to the motor tube, and coated the u-bolt nuts with epoxy.

MasonH · Dec 20, 2012

What epoxy is that?

qquake2k · Dec 20, 2012

MasonH said:
What epoxy is that?

I used 15 minute on the ring, and 5 minute on the nuts.

MasonH · Dec 20, 2012

qquake2k said:
I used 15 minute on the ring, and 5 minute on the nuts.

I tend to WAY overbuild most HPR kits and either use a crap ton of 15 minute epoxy or JB Weld.

qquake2k · Dec 20, 2012

I too have been accused of being heavy-handed with the epoxy. This is the other side of the centering ring.

chadrog · Dec 20, 2012

qquake2k said:
Anybody need a brand new never used custom made 1/4" centering ring with a small pre-installed u-bolt? I'll even autograph it for you! :tongue:

I'll take it if it's autographed!

troj · Dec 20, 2012

qquake2k said:
I too have been accused of being heavy-handed with the epoxy. This is the other side of the centering ring.

Eh, it's on the inside, what's it hurt?

I tend to end up with "bonus epoxy" on inside rings, too.

-Kevin

qquake2k · Dec 21, 2012

chadrog said:
I'll take it if it's autographed!

Unfortunately, there's no certificate of authenticity...

qquake2k · Dec 21, 2012

troj said:
Eh, it's on the inside, what's it hurt?

I tend to end up with "bonus epoxy" on inside rings, too.

-Kevin

I'm very messy with internal epoxy. It causes problems sometimes, but that's why God invented the Dremel!

iter · Dec 22, 2012

Looking good there Jim! I'm not even sayin' nuthin' about the 54mm.

qquake2k said:
According to Open Rocket, I'll need 14oz of nose weight in the X-Plane, and 24oz in my upcoming mystery project. I was going to get some lead shot, but none of the local gun shops sell it. So I got 4-1/2 lbs of BB's.

Your friendly local auto repair facility has a bucket full of old lead wheel weights just waiting to become something useful. You can then melt them, get rid of all the gunk that floats to the top and cast the exact shape you need. You may have to separate iron weights from lead--environmental preferences mean that some junk lead isn't lead at all.

Looking forward to the complete article!

Ari.

Quaranta · Dec 22, 2012

Looking great Jim.

New scratch build, X-Plane SST

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