Scratch build McDonnell XP-67
#26
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A buddy said I should make one of these. I haven't linked it in the build thread yet but I might as well. He's been bugging me about it so here's the shameless beggery. Will really help with the big one, but I'm not there yet.
http://www.gofundme.com/Mcdonnellxp-67
http://www.gofundme.com/Mcdonnellxp-67
#28
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The question is why not? It helps or it doesn't. Not a big deal either way. And if someone might happen to want one, well here ya go. Motors and esc's came in today. Just barely going to fit. Probably a bit too big. From rough calculations it's looking like almost 1:1 power to weight. Kinda overkill I think. I'll see how they work out and can always downgrade.
oh and so far this one has gone no where too, which isn't all that unexpected.
oh and so far this one has gone no where too, which isn't all that unexpected.
Last edited by Mms_citrus; 12-13-2017 at 06:21 PM. Reason: Response
#30
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yea I think it's really a cool looking plane. As far as I read it actually flew ok, just never performed up to expectations. Engine problems I read. However correct me if I'm wrong. And as far as flying better, if it doesn't burn down on the tarmac I'll be a step ahead
#31
yea I think it's really a cool looking plane. As far as I read it actually flew ok, just never performed up to expectations. Engine problems I read. However correct me if I'm wrong. And as far as flying better, if it doesn't burn down on the tarmac I'll be a step ahead
Based on the location of the landing gear it seem like the CG on the full scale would have been as expected in relation to the relatively conventional outboard wings but I wonder how much all of the area in the aft fuselage/engine fairing is going to effect the trim.
Last edited by mgnostic; 12-14-2017 at 04:23 PM.
#32
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so much waxing waiting for some free time to lay up some fiberglass. Got all my mold materials. Everything is cut and ready to go.
ive made up some test panels, just laminated 2 layers. 4&4, 4&8, 8&8oz cloth. I think the 4&4 will be sufficient. I’ll know in another day when it cures all the way. Ive been estimating weights and I think I’ll have a fuse with the few bulkheads I’ll need at just a little over 1lb.
ive made up some test panels, just laminated 2 layers. 4&4, 4&8, 8&8oz cloth. I think the 4&4 will be sufficient. I’ll know in another day when it cures all the way. Ive been estimating weights and I think I’ll have a fuse with the few bulkheads I’ll need at just a little over 1lb.
Last edited by Mms_citrus; 12-21-2017 at 07:03 PM.
#33
Wax on, Wax off, Daniel san.
#35
I'm getting a bit out of my depth but if it were me I would go with an egg crate structure that would serve as spar carry through and tie your engine boxes to the overall airframe. I've seen glass fuselages that had little more than just the formers to hold the cross section but since your design has a relatively flat section I would be concerned about twisting in torsion, hence the eggcrate suggestion.
#36
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My wing and elevator mold are done. Only 1 void I will repair. The surface coat was thick enough to cover any of the little air bubbles. Learned a lot doing this.
im not gone repair it actually. It’s not a void actually just a think spot over a bubble. If it ruptures then I’ll have to.
im not gone repair it actually. It’s not a void actually just a think spot over a bubble. If it ruptures then I’ll have to.
Last edited by Mms_citrus; 12-30-2017 at 10:01 AM.
#38
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Yes, in the park size for starters. When this is done I have to decide whether or not to start the 100+ ws model, or start another park size, under 50”. The next model aircraft will be the heinkel he-112 v5 version most likely. All the pre b models are pretty similar. I suppose when this is done I’ll do a poll to see what would be more interesting. What you all think? I’ve been out of the hobby for a while. Do people want big expensive planes or smaller cheaper ones?, not that money and selling these was really the primary factor, but if i can help fund the next build then I guess that’s good too.
#41
Yes, in the park size for starters. When this is done I have to decide whether or not to start the 100+ ws model, or start another park size, under 50”. The next model aircraft will be the heinkel he-112 v5 version most likely. All the pre b models are pretty similar. I suppose when this is done I’ll do a poll to see what would be more interesting. What you all think? I’ve been out of the hobby for a while. Do people want big expensive planes or smaller cheaper ones?, not that money and selling these was really the primary factor, but if i can help fund the next build then I guess that’s good too.
#42
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Do you think 42” needs removable wing sections? I’m thinking now about laying up the wings and fuse as 1.
bear in mind the fuse without the wings is still something like 22” wide.
bear in mind the fuse without the wings is still something like 22” wide.
Last edited by Mms_citrus; 01-05-2018 at 07:51 PM.
#43
I suppose it depends on what you want from the removable wings. Of my three most recent sub 48 inch wing airplanes, two only ever had the wings removed for maintenance. The third had wings held on by rubber bands and so those got taken off at the end of every flying session. This may just be personal preference on may part as I have the luxury of a pickup with a camper shell and can just put the planes in the back. Three immediate reasons come to mind for removable wings. Shipping, as in arfs, is a factor for mfgs. Convenience in getting to and from the field. If you are driving a Miata every little bit helps. Maintenance is the third thing. Many conventional airplanes remove the wing for access to the interior of the fuselage. The XP-67 with its blended fuselage probably just needs a hatch. At this point you are more of a fiberglass expert than I. My own personal preference would be to build the wings separately and than permanently attach them to the fuselage. The cool thing about this is; it's your experiment. You have the plugs and molds. With an airplane this small you can crank out a couple of prototypes to try different ideas.
#45
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ok. Keep watching the build. I pulled the mold apart today. I’m going to bolt it all up and add a couple more layers to it, and I’m going to blend the wing molds to the fuse mold. I still have to make a couple small repairs to the molds but I’m super satisfied with my first attempt.
#47
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I suppose it depends on what you want from the removable wings. Of my three most recent sub 48 inch wing airplanes, two only ever had the wings removed for maintenance. The third had wings held on by rubber bands and so those got taken off at the end of every flying session. This may just be personal preference on may part as I have the luxury of a pickup with a camper shell and can just put the planes in the back. Three immediate reasons come to mind for removable wings. Shipping, as in arfs, is a factor for mfgs. Convenience in getting to and from the field. If you are driving a Miata every little bit helps. Maintenance is the third thing. Many conventional airplanes remove the wing for access to the interior of the fuselage. The XP-67 with its blended fuselage probably just needs a hatch. At this point you are more of a fiberglass expert than I. My own personal preference would be to build the wings separately and than permanently attach them to the fuselage. The cool thing about this is; it's your experiment. You have the plugs and molds. With an airplane this small you can crank out a couple of prototypes to try different ideas.
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Everything is lining up and looking good. Fits perfectly. Seams are flush. Doesn’t appear to have taken on any warpage despite being a little thin. Now I can remold the wings and let this all kick over for a week or so.