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Boof69
11-10-2011, 01:54 AM
I went fishing through the request thread and came across a request from very far back. Like 2008 from Norton. I found out no one ever built the XP-67. So I got a nice 3 view with 22 cross sections in all and set up a studio. It took 2 hours to cut it up and set up the studio!

Norton
11-10-2011, 02:25 AM
One was built and tested, burned from a engine fire.

I know you've seen this Boof, this is for everybody else. ;)

RCU build thread: http://www.rcuniverse.com/forum/m_9012394/mpage_1/key_/tm.htm

Video footage:http://www.youtube.com/watch?v=SZHSUTYKf4U

If they only would have put the right engines in it :(

(EDIT) When you said nobody ever built it you meant for the sim. Duh..........

Kmot
11-10-2011, 12:49 PM
Sweetness!!! :D

There are tons of super cool X planes that could be modeled. I am really excited to see this on your drawing board. :)

Boof69
11-10-2011, 09:35 PM
I'm making this one using the edge copy method. It's used when modeling organic shapes such as the human form, but the smooth contours of the XP-67 are very organic. While forming the shape things look pretty weird and there is a fair amount poly shaving that will take place after the general shape is flushed out, but this is the fastest method I know of to use for this model.

Norton
11-11-2011, 12:37 AM
This plane was going to be a b---- from the get go. Very valiant effort on your part. :cool:

I'm sure justice will be done.

Cheers Boof..........................

Boof69
11-17-2011, 08:37 PM
I've had my brother up from Florida and have had other distractions but I found some time tonight to sculpt a bit more on the XP-67. This is a challenge for sure, but once I get past the aft section of the fuse it will be pretty straight forward. I will just need to extrude the wings and make the horizontal stabilizer. Then Landing gear and maybe a cockpit. Only If poly count will allow. I fully expect to be able to reclaim polys after to fuse and nacelles are finished. Right now though I already have 2366 polys involved. eek! :eek: Fingers crossed.

maxx2504
11-17-2011, 10:39 PM
Hi !

This thing reminds me of a Star Wars Starfighter :P ...Nice work so far... ;)


maxx

Boof69
11-17-2011, 11:45 PM
It's unique for sure. Thanks maxx :)

Norton
11-18-2011, 03:34 PM
Looking really nice :D

YF-23ace
11-18-2011, 05:34 PM
Will there be a G5.5 version?

brields
11-18-2011, 06:00 PM
If you made a G5.5 version, I'd be verry happy. The XP-67 is one of my favorite
military experimental planes.

Mikeymike21
11-18-2011, 06:03 PM
If you made a G5.5 version, I'd be verry happy. The XP-67 is one of my favorite
military experimental planes.
You only need to change the physics. G6 still uses .rfx extension.

td9cowboy
11-18-2011, 06:27 PM
You only need to change the physics. G6 still uses .rfx extension.
Or purchase RF6. ;)

Norton
11-18-2011, 07:36 PM
If you made a G5.5 version, I'd be verry happy. The XP-67 is one of my favorite
military experimental planes.

I find it hard to believe that most people even knew about this plane. Let along you.


It was a plane that most of the public never heard about?

Whatever though. ;)

brields
11-18-2011, 07:39 PM
http://en.wikipedia.org/wiki/McDonnell_XP-67 You'r dealing with someone who researches military airplanes as a HOBBY. ;)
That's why there are more full scale aircraft variants on the swaps now. :D
btw. I'm not MOST people, encase you haven't noticed.

Boof69
11-18-2011, 07:40 PM
I hadn't planned to make a G5.5 version. I really want to get familiarized with RF 6 physics and I don't like making AVs, but maybe someone else will end up doing it. :)

Norton
11-18-2011, 08:21 PM
http://en.wikipedia.org/wiki/McDonnell_XP-67 You'r dealing with someone who researches military airplanes as a HOBBY. ;)
That's why there are more full scale aircraft variants on the swaps now. :D
btw. I'm not MOST people, encase you haven't noticed.

So your responsible for all the scale models on the swaps? Your simple query to wiki is very funny by the way.

Give me a break

EDIT: I will give you this, you are getting better at the forum thing. It only gets better I hope. ;)

brields
11-18-2011, 09:26 PM
The wiki link was a joke. but I am getting better at socializing.

Boof69
11-19-2011, 12:50 AM
Fully enclosed geometry and all parts of the airframe modeled. Hard part is done!
Gear and cockpit left to model. Poly count is a little high at 3637, but I think I can wring out some extra polys before it's done.

Norton
11-19-2011, 12:59 AM
I know this one threw you for a loop, looking real nice.

Mikeymike21
11-19-2011, 01:03 AM
Looks great

Boof69
11-19-2011, 01:06 AM
It really just took patients to this point. I will need more to tweek it even more, but how smooth could this plane have been with 40s tech. If I leave a few dents here in there it will just add character.

Norton
11-19-2011, 01:10 AM
I hadn't planned to make a G5.5 version. I really want to get familiarized with RF 6 physics and I don't like making AVs, but maybe someone else will end up doing it. :)

I may take a stab at that. I have G3, G4, G5 and now G6 installed on the computer.

That's if I have time?????

Boof69
11-19-2011, 01:33 AM
AVs are welcome as always. :)

brields
11-19-2011, 02:30 AM
Looking good. Had the XP-67 been put into production in 1942, (it wasn't invented until 1946 or 47) it would have been one of the best fighters of WWII.
One thing I don't know is, where would the guns be located?

Boof69
11-19-2011, 03:57 PM
Thanks Glad you like it.
I have the main gear setup and they fit nicely in the nacelle. The NUP values are set for those as well. I still need to cut the doors and make the gear for the Steering gear. Also I cut the control surfaces w/hinges. Polys have climbed to 6489 as you can see. I still haven't found a solution for the shading errors at the rear of the nacelles. Overall I'm happy with it still.

U-Bird
11-19-2011, 04:15 PM
Your "BAT" is really looking GTREAT!! The FS plane, the engines were it's weak link, problems never resolved. Should be a interesting flyer.

Boof69
11-19-2011, 04:20 PM
I know they had problems. Not even a replica exists as far as my research has turned up. That will cause some improvisation on my part. It should fly nicely.

U-Bird
11-19-2011, 08:48 PM
I think most here will be happy with what ever you take upon yourself to improvise and make work for our behalf. We gots no complaints mon!! You have us standing in line, quietly waiting for your next work of art. It's good to know some of the best!!!
How is RF6 working out now?

Boof69
11-20-2011, 04:09 PM
Very flattering as always U-bird.
As for RF6 I haven't built up physics from a clean slate yet, only edits. I think it's capable of more accurate physics to real life than previous versions, but I won't know for sure until I get this one into RF and start the physics.

brields
11-20-2011, 06:30 PM
What scale is the model going to be?

Boof69
11-20-2011, 06:37 PM
Haven't really decided yet. I will be looking into that and set it before my first export. Most likely between 6 to 9 foot wingspan. Whatever % that works out to be.

Boof69
11-20-2011, 11:45 PM
I finished all the required parts needed for an export. Including the landing gear and doors. I'm happy to report that the NUP values were almost totally correct on my first import into RF 6. Does anyone know a good rule of thumb for figuring out ahead of time whether a part needs a negative or positive value. I don't know from what view of the model this is based. Also does it matter if I export with the gear up or down. Down seemed to work fine, but maybe there's an advantage to exporting with them retracted. :confused: Also does anyone know what would cause the wheel to separate from the gear it's parented to when not under the weight of the model? The wheels are below the gear when in the air. Is it the type of retracts maybe? anyways I have it in RF 6 and I used the de Havilland Mosquito as a quick setup because of the configuration of gear and motors. Here's some shots.

willsonman
11-21-2011, 12:03 AM
I know that all sorts of issues can take place if you model your gear in place and them unfold them in max and them export. My rule of thumbs has been to model everything with gear down. Gear doors are the exception. The Polikarpov I-16 I did gave me nothing but a nightmare of trouble trying to get the gear to work right. The angles I had to enter for the correct rotation made no sense. At one point I gave up and released it only to be hammered with bad critiques. I redacted the model and pressed forward to fix the issues.

My suspicion is that you have a weird issue with your wheels' pivot point. Generally the pivot point works fine because it usually only uses the x axis for rolling but the Mosquito I know uses a Springy scale landing gear type. This simulates the oleo strus by simply having the tire bob up and down rather than the actual gear. This is then done on the y-axis. You get a great image of how this works if you simply align the pivots to the correct x axis and then export and incluse the springy scale retracts. It looks funky.

to my point...If you have modeled the gear and then rotated it correctly into position the wheels' pivot will also carry along that path. If you have rotated the gear an odd angle here or there it will reflect in the way the wheel will rotate or bounce. The wheel location should be set to the weighed-down point in 3DSMax when using this type of gear. Then adjust your springiness factor to accommodate excessive bouncing and sag in the strut. Keep in mind that weight also affects this.

Boof69
11-21-2011, 12:10 AM
The wheels pivot is set correctly for the extended position and the gear are only rotated in the X 110 degrees. If I'm understanding you I should pre load the wheels? What position would they be in under a load? Or are you saying that I should use a different retract type?

willsonman
11-21-2011, 12:18 AM
I would suggest troubleshooting by going simple first. Change gear and note the location of the wheel. It should be where it was modeled. If using a springy scale gear it may sag or be extended on the above factors I mentioned. However you want to have it exported in the position it should be at when on the ground.

Boof69
11-21-2011, 02:08 PM
The gear are no longer a problem. They fixed themselves as I set up the custom physics. I believe it was from the gear in the editor not lining up with the visual ones. Once that was done the problem went away.
I have one more problem and I think I know the answer but I hope it's not what I think.
The props are not showing up which is weird because my ~CS_ENGINE objects are not showing in their place. The left engine object is named ~CS_ENGINE1 and the right is named ~CS_ENGINE2 the spinner objects the same way the left having a 1 at the end the right a 2. All four objects are parented to the fuse because the fuse and nacelles are all one piece. I'm guessing that this is the problem. If I separate the nacelles from the fuse there will be a visible seem. I would like to avoid that if possible. Has anyone ran into this before? Help! :(
On an up note I figured a good way to apply airfoils to the fuse. Since it's a lifting body that changes shape laterally I thought it would be more accurate to use multiple airfoils (4 in all) to represent the shape. I then set the "Fuselage Aerodynamics percent" to 0 to disable any lift or drag that would compound to the airfoils I set up. Worked like a charm. I'm sure that's how others have done it in the past. Just thought it was worth a mention.

Boof69
11-21-2011, 02:39 PM
Here are some pics of the airfoils setup for the fuse.

willsonman
11-21-2011, 04:45 PM
Looks good but I would keep frontal drag at about 50%. Reason being that you are substituting wings in the physics for the nacelles. You still have a fuselage in the middle. Your actual reduction is drag may be less but you may have to just play around with that number until it seems realistic.

Boof69
11-21-2011, 04:47 PM
I see your observant. ;) I will try it out. I let you know how it helped.

dhk79
11-21-2011, 05:26 PM
I've run into the dual engine problem before. Try setting the engines up as being a sub of the airframe, rather than the fucelage.

Doug

Boof69
11-21-2011, 05:40 PM
That did the trick. Thanks Doug. I had left the engines in the wings from the mosquito model I imported as. Awesome!

Boof69
11-23-2011, 11:23 PM
So after quite a bit of fuss and headache I have the fuse mapped. Which is the bulk of the model. The rest should go quickly "I hope"!

Boof69
11-24-2011, 12:41 AM
Looks good but I would keep frontal drag at about 50%. Reason being that you are substituting wings in the physics for the nacelles. You still have a fuselage in the middle. Your actual reduction is drag may be less but you may have to just play around with that number until it seems realistic.
I ended up with A frontal drag of 25% and a parasitic Drag factor of 50%.

Boof69
11-24-2011, 02:49 PM
Everything on the XP-67 is mapped and ready for paint. I may add some small things under the canopy at a later time, but there is room for that on the map. I am using some robart gear uploaded to the parts repository by wilsonman. They chunked on 2230 polys bringing the total up to 9407. I haven't tried to see if any optimization can be done on the gear yet.
So few pictures exist of this plane and the ones that do aren't in color. So I think that I will closely emulate the CS on the F9F Panther from EP 8 (my favorite model in that pack). Incidentally there is a mistake on the F9F. The left wheel pivot is 180 degrees off and the wheel rotates backwards. Just a trivial mention.

willsonman
11-24-2011, 08:01 PM
I'm sure you can clean up that gear a bit. I made it quite awhile ago. Looking really great. I'll have to observe the F9F. I'm not much of a jet guy so I've only flown it once just cause thats what I do when I get a new EP. See if I can land it on a maiden. Its always a fun challenge.

Mikeymike21
11-24-2011, 08:09 PM
http://stargazer2006.online.fr/bonus/manta1.jpg

Boof69
11-24-2011, 08:38 PM
I seen this one before mikey, but it's colored in PS and there are no other angles.

Boof69
11-24-2011, 08:52 PM
I'm sure you can clean up that gear a bit. I made it quite awhile ago. Looking really great. I'll have to observe the F9F. I'm not much of a jet guy so I've only flown it once just cause thats what I do when I get a new EP. See if I can land it on a maiden. Its always a fun challenge.
Actually I was able to shave 500 polys from them without too much reduction of quality.

brields
11-24-2011, 09:43 PM
Mikey, your photo is fake. Its been photo shoped. See how the background seems
to be taken by a modern camera, and then superimposed with a post WWII era photo?
The pixles are mixed up.
I can even see that the lighting doesn't match up.

Mikeymike21
11-24-2011, 10:27 PM
Yes I know its fake.

Boof69
11-26-2011, 07:43 PM
I started laying in color today. Just colors and signage. No real detail to speak of. The canopy windows are done in the color scheme to save polys. I've added two four stroke heads to the engine to show function for those who may want a that RC look by Norton's request. I used Doug's (dhk79) Saito Golden night engine (and changed the colors) and deleted any part of the motor not visible to save polys. So unless I add some small details the XP-67 is at 16353 for polys and the heads account for 6720 of those. Here's what I've got so far.

willsonman
11-26-2011, 09:19 PM
Perfect fit. Beautiful motors for a beautiful plane.

Boof69
11-27-2011, 10:00 PM
Put a little more time in and started the bump. I have most if not all of the panel lines layed in and started with some grime.

Boof69
11-30-2011, 11:06 PM
So am I correct in assuming that whatever state the "Engine to show" function is in during my .rfx export will be the default state for the end user?
For example if I don't want the 4stroke option by default then do I have to have the 2Stroke option active during export?

jeffpn
11-30-2011, 11:08 PM
Engine to show is just a physics parameter like any other. It's all part of the AV. That's the long way of saying, "Yes."

Boof69
11-30-2011, 11:23 PM
Thanks ya. :)

Boof69
12-01-2011, 01:49 AM
I think everything is pretty much done. I need to set component strengths yet, and I haven't added exhaust. I need to look up information for the description. The model itself and CS are done I think. Here are some pics. :)

Norton
12-01-2011, 02:18 AM
I think everything is pretty much done. I need to set component strengths yet, and I haven't added exhaust. I need to look up information for the description. The model itself and CS are done I think. Here are some pics. :)

Looks great Boof, thanks for taking it on. Now if I can ever get home for a minute and stop working, I'd love to fly it. When it's posted that is.

I may be home for the weekend? Then back down to the Bay Area for another week :(

Cheers.

Boof69
12-01-2011, 02:19 AM
It should be posted tomorrow.

Boof69
12-01-2011, 08:35 AM
Nice looking work. Those cabinets are naked. Will you be finishing them?
I have to say I don't miss residential construction. I did it for 20 years before it crashed here in Michigan. I was a drywall finisher for about half of those and a sander for the other. Very hard work. I still do some drywall work from time to time in my new line of work. Nothing like the $200,000 to $1,000,000 plus homes I used to work on, but drywall none the less.

Norton
12-01-2011, 10:15 AM
Normally I finish my own cabinets. There is going to a finisher coming in next week, thank God.

Boof69
12-01-2011, 04:11 PM
Posted! (http://www.knifeedge.com/forums/downloads.php?do=file&id=15888)

maxx2504
12-01-2011, 05:25 PM
Hi Boof !

I have one Problem with this Airplane:

Unable to locate 'NACA 8-H-12' in the list of available Airfoils. A default will be selected.



maxx

Boof69
12-01-2011, 05:36 PM
Update to the latest beta. I presume you are running 6.00.25. There was a problem with this beta release. It was fixed in 6.00.26 but the latest beta is .27.LINK (http://www.knifeedge.com/forums/showthread.php?t=27808)

jeffpn
12-01-2011, 05:37 PM
Are you running 6.00.027?

maxx2504
12-01-2011, 06:20 PM
Hi !

Im SORRY. My fault...i still run .025. Upgraded it now to .0.27.

Shame on me :(


maxx

Boof69
12-01-2011, 06:24 PM
No biggie. :)

Kmot
12-01-2011, 06:41 PM
:)

http://www.youtube.com/watch?v=SZHSUTYKf4U

Boof69
12-01-2011, 11:03 PM
Yeah that's a good video. Norton posted it in post #2.

willsonman
12-02-2011, 08:54 AM
She is a beautiful model but I think the physics are completely lackluster. 6 oz for the v-stab and rudder and 6 oz for a 24" wing? Really? You could have really benefitted from a helper object to get the fuselage shaped right.

Keep up the great work though. Just work more on the physics... and yes I did read your disclaimer on the swap page. Just some friendly critique. Again, great looking model.

Boof69
12-02-2011, 09:02 AM
Are you saying that you don't like the way it flies or do you just disapprove of the physics from a purist standpoint?

willsonman
12-02-2011, 09:17 AM
Not from a purist standpoint... there is very little data from my brief research. I do think that there are many things that you could have done that have been written up on in many of the tutorials on physics here.

I personally think that for the given weight and wing loading it is a particularly "floaty" plane. Leading me to believe you have far too much lift from the way you linked the fuselage and nacelles. Then adding a wing there just makes more lift even though you reduce fuselage aerodynamics. You put two large masses at teh tail and nose... pick one. Adding weight for weight sake is just crazy. Why would you want it heavier than it has to be. Weights all around seem unrealistic.

Boof69
12-02-2011, 09:25 AM
I see what your saying and I'm sure your right. The one confusing statement is that its floaty. Its far from floaty in 6 anyway. I ran into some unique problems with the physics setup and tackled them in a unique way for me anyhow. I don't understand what you meant by a helper object to get the fuse shape right. Could you explain?

willsonman
12-02-2011, 09:48 AM
http://knifeedge.com/forums/downloads.php?do=file&id=12944
In the BV-141 I used a helper object to get the aircraft centered and used that as the main root of the aircraft. The fuselage parts were added. Its a trade off as severe crashes are odd but it flies more true.

A wing loading of 27.215 oz/sq.ft. is not going to give the glide factor you are getting. Basically the model is too heavy for the wing area you are calculated to have.

My suggestion would be to separate the wings/nacelle areas from the fuselage. Then use your wings setup as-is to simulate the streamlined area. You could use helper objects for the nacelles or just separate them and use the wings and add the nacelles but I think you would run into additional lift then as well. Just add the engines to the wings so they properly break off when the wing breaks. The wing should be the parent of the engines... not part of the root of the aircraft. I hope this clarifies.

td9cowboy
12-02-2011, 10:42 AM
Anyone care to take a look at this one? I've pretty much been through it. Great model Boof. I'm enjoying flying it.

andy29847
12-02-2011, 12:05 PM
She is a beautiful model but I think the physics are completely lackluster. 6 oz for the v-stab and rudder and 6 oz for a 24" wing? Really? You could have really benefitted from a helper object to get the fuselage shaped right. Keep up the great work though. Just work more on the physics... and yes I did read your disclaimer on the swap page. Just some friendly critique. Again, great looking model.

I flew the model last night and it flew good in 5.5. I would like for it to be bigger and faster, but that is how I am about most planes. The discussion about physics is interesting. The 2 lines of thought seem to be "make it just like a model" and "make it fly like a model (or some times like the real plane)". My limited experience has found that radical adjustments in weight, weight distribution, and power are needed as the planes get more complex and/or bigger. Since I am a end product kind of guy, and all my flying is on the computer, adjusting physics via unusual values works for me. Regardless, I appreciate and enjoy all of the models that are loaded on the swap pages. Youse guys do a great job.

Ghost129er
12-02-2011, 01:14 PM
Beautiful Model Boof, flew really well and was hoping to make some schemes for it, though its an experimental plane, (military, patrol, aerobatic team, etc) Let me know if I should.
Ghost :)

jeffpn
12-02-2011, 01:50 PM
Once a model hits the swaps, you can post any AV or CS as you see fit.

Boof69
12-02-2011, 01:54 PM
Beautiful Model Boof, flew really well and was hoping to make some schemes for it, though its an experimental plane, (military, patrol, aerobatic team, etc) Let me know if I should.
Ghost :)
Once I post a model to the swaps it's fair game for anyone to create CS's or AV's from that model. Feel free to paint away. :)

Kmot
12-02-2011, 01:56 PM
I am flying this in G5.5, and like 98% of every plane I have downloaded from the Swap Pages, I had to tweak the physics. I don't even consider that an issue and it never is part of my rating when I rate a plane on the swaps.

I find I need to tweak the physics on most planes in order to make them fly:

1) How I like them to fly

2) How I would expect it to fly if I built it as a model airplane

I think it is a great model. Looks cool. I just wonder why it didn't get any flaps.

Boof69
12-02-2011, 02:50 PM
There are no flaps on the real life plane. I didn't notice any anyways.

willsonman
12-02-2011, 03:31 PM
Yes, I plan on posting an AV once I have it done. Working around the drag from the fuselage has been tricky but not impossible. Like I said, Its a wonderful model.

brields
12-02-2011, 04:41 PM
It seems a bit too agile.

Kmot
12-02-2011, 07:41 PM
There are no flaps on the real life plane. I didn't notice any anyways.
Boof, you can clearly see the flaps, or more technically correct 'flap panel', in the video when it lands. :)

Here is a better version of the video that can be watched full screen:

http://www.airspacemag.com/history-of-flight/Too-Hot-to-Handle-McDonnell-XP-67-Moonbat.html#

Boof69
12-02-2011, 08:05 PM
Would have been nice to have that piece of info earlier. Hind sight is 20/20. Too late now. Maybe I'll revisit at some later date. Thanks for the information dig up kmot. :)

Boof69
12-02-2011, 10:52 PM
. Great model Boof. I'm enjoying flying it.
Thanks Steve. I'm glad that you are enjoying it. Have you hooked a grapple to it yet? :p

td9cowboy
12-02-2011, 11:28 PM
:D No grapple yet but pulling a banner with a plane might be cool. I don't find a need for flaps Boof, it lands great for me now. Bad azz plane!

Boof69
12-02-2011, 11:57 PM
Thanks Steve

andy29847
12-03-2011, 11:10 AM
Here she comes!!

andy29847
12-03-2011, 11:35 PM
Today was XP-67 day. Thanks to Boof69 for the model. An AV, a CS, and a recording. Not only that, I put up the Christmas tree too. :)

Boof69
12-03-2011, 11:40 PM
You definitely get mileage out of the models at the swaps. I'm so glad your having fun with the XP-67. Enjoy!

Mel2498
02-13-2013, 11:06 PM
I built and fly a BV-141, there are a couple uploads of the plane here but none fly exactly like my model. Is there a good reference on the site for making adjustments?

Link to my plane in flight: http://www.rcscalebuilder.com/forum/forum_posts.asp?TID=18829&PN=1

Boof69
02-13-2013, 11:10 PM
What does this post have to do with the McDonnell XP-67?

pplace
02-14-2013, 08:55 PM
What does this post have to do with the McDonnell XP-67?

Who knows, but your comment certainly doesn't really give a nice "welcome" to the forum.

Mel2498: I thought I remembered a topic started by member dhk79 that dealt with proper "setup, trimming, etc." in order to tweak the physics to gain proper flight characteristics. I searched for such thread and couldn't find it. Possibly you could contact him to see if he still had the information.

Boof69
02-14-2013, 09:42 PM
Really? Why? It's a simple question. I didn't mean anything by it.

dhk79
02-15-2013, 09:55 AM
Mel2498,

The physics tutorial is still here. It's buried way back on the G3 Designers Corner: http://www.knifeedge.com/forums/showthread.php?t=17498

Some of the menu options have changed with newer RF versions, but the concepts are still the same.

Doug