Marutaka P-38
#26
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RE: Marutaka P-38
Now that was just plain COOL! You did a good job with that, I see R/C isn't your only hobby! Hey, you're not the one who keeps sending out those pic's of Bush's head on a kids body are you?
I keeping flipping back and forth between the pictures and notice you even replaced the areas previously covered by the engine and muffler and even background.
Anyhow, to the point. Thanks for providing a simple solution to the problem. Here I was thinking of all other kinds of fixes that still wouldn't have the desired result. I'll try yours tonight. If all else fails, I'll try LRB75's suggestion and mount them sideways. I already have several Pitts mufflers that will work for that.
I keeping flipping back and forth between the pictures and notice you even replaced the areas previously covered by the engine and muffler and even background.
Anyhow, to the point. Thanks for providing a simple solution to the problem. Here I was thinking of all other kinds of fixes that still wouldn't have the desired result. I'll try yours tonight. If all else fails, I'll try LRB75's suggestion and mount them sideways. I already have several Pitts mufflers that will work for that.
#27
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RE: Marutaka P-38
Glad you like it! It was just a fast job, but yes I also work with photo's and restoration. You may want to add fiberglass cowls for this, that would give you extra room around the engine. Side mounted engines are fine too, hope you get it worked out to your satisfaction.
Dion
Dion
ORIGINAL: DamonTX
Now that was just plain COOL! You did a good job with that, I see R/C isn't your only hobby! Hey, you're not the one who keeps sending out those pic's of Bush's head on a kids body are you?
I keeping flipping back and forth between the pictures and notice you even replaced the areas previously covered by the engine and muffler and even background.
Anyhow, to the point. Thanks for providing a simple solution to the problem. Here I was thinking of all other kinds of fixes that still wouldn't have the desired result. I'll try yours tonight. If all else fails, I'll try LRB75's suggestion and mount them sideways. I already have several Pitts mufflers that will work for that.
Now that was just plain COOL! You did a good job with that, I see R/C isn't your only hobby! Hey, you're not the one who keeps sending out those pic's of Bush's head on a kids body are you?
I keeping flipping back and forth between the pictures and notice you even replaced the areas previously covered by the engine and muffler and even background.
Anyhow, to the point. Thanks for providing a simple solution to the problem. Here I was thinking of all other kinds of fixes that still wouldn't have the desired result. I'll try yours tonight. If all else fails, I'll try LRB75's suggestion and mount them sideways. I already have several Pitts mufflers that will work for that.
#28
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RE: Marutaka P-38
just a little heads up, that wire could potentially act like a arresting wire and hurt your bird just keep in mind that the tail of the P38 is ment to be able to touch on landings if nessesary.
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RE: Marutaka P-38
Good point. Trouble is, I alread sheeted the right boom so putting another rod in is going to be tough. I took the wire off because like I said earlier, it's ugly. Looks like I'm gonna have to bite the bullet and get another tube in the right boom.
#30
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RE: Marutaka P-38
Almost done with my plastic parts set for the Royal P-38! VERY scale and extremely light not to mention it saves a ton of carving! I also show just SOME of the wood my parts eliminate! I'm not using RCU anymore but I thought some would be interested....
Chow!
Dion
P.S. Not shown are the rear radiators and the small intakes for the cowl, just a little more work to be done on those.
Chow!
Dion
P.S. Not shown are the rear radiators and the small intakes for the cowl, just a little more work to be done on those.
#31
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RE: Marutaka P-38
Hi!
I have built and flown some twins in my day and helped others with theirs and I recommend that you build yours light ..this is very vital to good flight behavior.
In a Marutaka P-38 .46 engines is way to much power!!! At least if you fly at sea-level.
I have seen this happen many times when people build twins...they always put in too large engines and then they get very disappointed when they see that their airplane flies like a brick...and not on its wing.
Being into pylonracing for many years I know what fast airplanes are and I definitely don't want my scale airplanes to fly that fast...and land that fast.
I want scale airplanes to be capable to fly slow and gentle, to be docile, and that is possible with ALL scale airplanes as long as you keep them light and remove weigh were-ever possible.
I would use .28-.32 engines in a Marutaka P-38 or OS LA .40 engines which are very light.
Aim for a weigh in the neighborhood of 3,5-4 kg.
Smaller engines require smaller and lighter fueltanks (170cc instead of 240cc tanks) lighter and smaller engine mounts and wood structure could be made lighter in the wing-pods.
Instead of having a flying brick at 5-5.5kg it could be possible to have a fast agile and slow flying P-38 at 3,5 or 4kg which would land like a trainer aircraft.
As for servos go for the lightest possible..I have good experience with Hitech Hs 85 and Hs 225 servos. I would use a single Hs85 on the side rudder and two Hs 85 or a single Hs 225 servo on the aileron.
I would skip the fowler flaps as they are to no use in a model this small. They are just for looks!
For throttle servo I would either go with a single Hs 85 or maybe with two Hs 85 or Hs 55 in each engine pod.
Regards!
Jan K
Sweden
I have built and flown some twins in my day and helped others with theirs and I recommend that you build yours light ..this is very vital to good flight behavior.
In a Marutaka P-38 .46 engines is way to much power!!! At least if you fly at sea-level.
I have seen this happen many times when people build twins...they always put in too large engines and then they get very disappointed when they see that their airplane flies like a brick...and not on its wing.
Being into pylonracing for many years I know what fast airplanes are and I definitely don't want my scale airplanes to fly that fast...and land that fast.
I want scale airplanes to be capable to fly slow and gentle, to be docile, and that is possible with ALL scale airplanes as long as you keep them light and remove weigh were-ever possible.
I would use .28-.32 engines in a Marutaka P-38 or OS LA .40 engines which are very light.
Aim for a weigh in the neighborhood of 3,5-4 kg.
Smaller engines require smaller and lighter fueltanks (170cc instead of 240cc tanks) lighter and smaller engine mounts and wood structure could be made lighter in the wing-pods.
Instead of having a flying brick at 5-5.5kg it could be possible to have a fast agile and slow flying P-38 at 3,5 or 4kg which would land like a trainer aircraft.
As for servos go for the lightest possible..I have good experience with Hitech Hs 85 and Hs 225 servos. I would use a single Hs85 on the side rudder and two Hs 85 or a single Hs 225 servo on the aileron.
I would skip the fowler flaps as they are to no use in a model this small. They are just for looks!
For throttle servo I would either go with a single Hs 85 or maybe with two Hs 85 or Hs 55 in each engine pod.
Regards!
Jan K
Sweden
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RE: Marutaka P-38
I have a royal P-38, Yes Lots of carving it seems, But a search on ebay for royal P-38 Gets you: a Cockpit Kit and a superchargers/scoop kit. I will be purchasing the supercharger/Scoop kit for further analysis. I even found and purchased fiberglass cowells, and I am sure plastic ones may show up now and again. With all of this Very little carving results in more time for detailing, and in My opinion a fun and more enjoyable kit to build. So Go search and see for yourself, Less carving, more appeal for the Marutaka/Royal P-38 kit. I can copy my directions for you if need be! Now if someone could either fiberglass or plasticize the nose, That would be a Godsend!
Fyre
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RE: Marutaka P-38
Jan K,
I am no expert, but I must say, I absolutely agree with you: We get into trouble when we depart from 1:1 scale thinking and doing.
Your advice is music to my ears! Keep things simple, keep weight down; power the thing sanely; fly a more SCALE flight regime; fly the wing; and --most fun of all-- be innovative in how you do these things. <---For example...You use the tiny HS-85MGs? Hehe...those are small servos, very small, but boy they are strong and tough little guys!!!
You remind me of our pal Luke (http://www.zollnermodels.com), for he builds, innovates, and flies with this same line of thought.
Thanks for your thoughts here!
John Rood
I am no expert, but I must say, I absolutely agree with you: We get into trouble when we depart from 1:1 scale thinking and doing.
Your advice is music to my ears! Keep things simple, keep weight down; power the thing sanely; fly a more SCALE flight regime; fly the wing; and --most fun of all-- be innovative in how you do these things. <---For example...You use the tiny HS-85MGs? Hehe...those are small servos, very small, but boy they are strong and tough little guys!!!
You remind me of our pal Luke (http://www.zollnermodels.com), for he builds, innovates, and flies with this same line of thought.
Thanks for your thoughts here!
John Rood
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RE: Marutaka P-38
I ended up ordering the cowls mentioned earlier in this forum that were listed on ebay. The original cowls were sold but the seller, D&B Model Products, offered to make up a new set. They arrived yesterday and I was very impressed. They fit perfectly and the workmanship was excellent.
After all the work on the front end, it was a little heartbreaking chopping it all off but in the long run these cowls will look better and are much much lighter.
After all the work on the front end, it was a little heartbreaking chopping it all off but in the long run these cowls will look better and are much much lighter.
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RE: Marutaka P-38
Here's a few more pics of the progress so far. The coolers are roughed out. They need to be touched up, attached and blended into the fuse. The top view was meant to show the wing tips (completed last weekend) and the fuse area above the wings. And finally you can see where all the wires ended up. There were a lot of extensions used. I made sure they were heavy duty and gold plated.
With regard to the servo weight issue. I now have a Hitec 5245 (mini digitals) installed for the ailerons and bought a Hitec 225 for the rudder. The flaps and throttle will be getting Hitec 85s in the coming weeks.
With regard to the servo weight issue. I now have a Hitec 5245 (mini digitals) installed for the ailerons and bought a Hitec 225 for the rudder. The flaps and throttle will be getting Hitec 85s in the coming weeks.
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RE: Marutaka P-38
Damon, your model looks great ...and so does your workshop!!!
I hope you're going to save the cowls you've carved...as a minimum, you can perhpas use them for molds, etc.?
John
I hope you're going to save the cowls you've carved...as a minimum, you can perhpas use them for molds, etc.?
John
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RE: Marutaka P-38
Thanks for the kind words. I tend to clean while I think which has kept the shop in very good order during this project. I was able to cut the original cowls off cleanly just in case the fiberglass ones didn't work out.
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RE: Marutaka P-38
Yes, I have to agree, The shop is beautiful, As well the 38!!!! I hate to mention this, as your coolers look so darn good, but have you considered the ones on ebay as well as the superchargers? Saves weight, and if you were to do rivets, one less thing to fiberglass! I am looking forward to more progress on your beauty!
#40
RE: Marutaka P-38
I put two OS .46 in mine, she flew great. What a screamer, Always got the blood flowing. No flaps so she came in hot. If i slowed down too much on approach, she would tip stall (fortunately at about a foot off the ground) . If I can give you one word of advice, Do NOT run an engine dry. Time your flights and never run out of fuel. I was having way too much fun with mine one day, and on the down wind leg of final, I lost my right engine, she did a very slow roll which I could not recover from. The Autopsy revealed almost two empty tanks. My fault. Someday I WILL have another P38. There is nothing like one in the air and in your hands! Good luck guys!
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RE: Marutaka P-38
Fili.... Sorry about the loss, it sounds like you really enjoyed that plane and it looked great too. I'm also going to power mine with .46s.
There been some talk in this thread warning about overpowering so I want to explain my decision here. In 25 years of flying I've never come across an engine better and more reliable than a .46 FX. Of course everyone has their favorites and I respect that, but this engine has never let me down.
I'm a very slow flyer. One of my favorite things is to go up on a windy day and try to park the plane in one place, or as in the case with an old Kadet of mine, get it to go backwards. While I know better than to do this with a P-38, I can trust these engines to carry a low idle when needed and keep a constant throttle setting after I've adjusted them accordingly. I suppose I could go with a couple .40FXs instead but I've only got one of them and already have several well broken in .46s.
There been some talk in this thread warning about overpowering so I want to explain my decision here. In 25 years of flying I've never come across an engine better and more reliable than a .46 FX. Of course everyone has their favorites and I respect that, but this engine has never let me down.
I'm a very slow flyer. One of my favorite things is to go up on a windy day and try to park the plane in one place, or as in the case with an old Kadet of mine, get it to go backwards. While I know better than to do this with a P-38, I can trust these engines to carry a low idle when needed and keep a constant throttle setting after I've adjusted them accordingly. I suppose I could go with a couple .40FXs instead but I've only got one of them and already have several well broken in .46s.
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RE: Marutaka P-38
When, I build my Royal P-38, I may use 4 strokes, for sound, plus I plan on swinging 3 bladed props, retracts, the whole bit. I must say, watching this thread is getting me anxious to get going on that project, but many others before I decide to tackle the 38. Keep the Pix coming. One other thing, why NO retracts in your 38? That bird looks so cool on a low fly bye with the gear up!
Fyre
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RE: Marutaka P-38
Well, I guess you could say I'm probably the slowest person around for moving up the difficulty scale. My father and I recently counted the airplanes we've built and this project makes 67 for me. I've moved from u-control->gliders->power gliders->trainers->high wing sport->low wing sport->bi-plane->quickee->scale->large scale->aerobatic->large scale aerobatic->float->plan built->scratch and this makes my second twin. I guess I haven't considered myself up to retracts yet just like I haven't moved to ducted fans or attempting a Top Gun or Scale Masters type project.
My main goal on all of them is mechanical soundness. To me this comes way ahead of detail. Although I have to say, I normally build more than one of the same plane so there may be a second P-38 in the future. My next project is a 70" Ziroli P-47 and last night I was looking into Robart retracts for that one. If I don't, then my next logical step is the larger sized P-47 which will definitely get them if the smaller one doesn't.
My main goal on all of them is mechanical soundness. To me this comes way ahead of detail. Although I have to say, I normally build more than one of the same plane so there may be a second P-38 in the future. My next project is a 70" Ziroli P-47 and last night I was looking into Robart retracts for that one. If I don't, then my next logical step is the larger sized P-47 which will definitely get them if the smaller one doesn't.
#45
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RE: Marutaka P-38
Most of my airplanes have inverted cowled engines and when I do that setup I keep a few things in mind. An old man once told me to make sure the stopper on the fuel tank is level with the carb and run the engine for a few minutes before flying to break loose any oil residue that may have built up in the head since the last time I flew. Also the engines I'm using are very well broken in .46 FXs that have been on other airplanes. Each time I fly a twin or any other plane for that matter I have a pretty strict routine that I stick by before takeoff. This is mainly done for safety reasons but it has shown to ensure that I have a reliable engine on takeoff.
This is by far the most involved airplane I've built so before permanently installing the engines, I'm going to bench-run them together to make sure they will run at similiar RPMs at all throttle ranges. If not, I'll get new ones.
I just got a bunch of new parts in today so the construction will start moving alone shortly till I go on vacation. The cowls are cut and the engines are fitted per a very smart recommendation early in this thread. I'll post a few new pictures this weekend.
COVERING!!! This is next. I wanted to do poly over .75 oz. cloth but figured that would be a mistake since I stupidly permantently installed the hinges. So, I'm considering Flight Metal. If anyone has any experience with this please let me know.
This is by far the most involved airplane I've built so before permanently installing the engines, I'm going to bench-run them together to make sure they will run at similiar RPMs at all throttle ranges. If not, I'll get new ones.
I just got a bunch of new parts in today so the construction will start moving alone shortly till I go on vacation. The cowls are cut and the engines are fitted per a very smart recommendation early in this thread. I'll post a few new pictures this weekend.
COVERING!!! This is next. I wanted to do poly over .75 oz. cloth but figured that would be a mistake since I stupidly permantently installed the hinges. So, I'm considering Flight Metal. If anyone has any experience with this please let me know.
#46
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RE: Marutaka P-38
This may seem like a dumb question, but does everyone glue the tail section to the booms? Seems like the logical thing to do instead of pinning as the plans indicate. [8D]
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RE: Marutaka P-38
I'm going to glue them. However, when I do that I'll have to make some sort of brackett across the front of the airplane for transport. This is because it wouldn't take too much of a twist to rip the stab in half.
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RE: Marutaka P-38
dionysusbacchus made a suggestion earlier that I cant the engines so I wouldn't have to cut away so much of the cowl for the muffler...here is the result.
#50
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RE: Marutaka P-38
Have you tried Wing products. Their P-38 is only one inch shorter in span and the canopy will work fine, Not sure if they are still in business however. Just about ready to start a new Wing 38 and I intend to use my old Royal canopy on this new wing kit which was missing on the kit I have. As for a cockpit kit there is probably not much out there and its easy to detail headrest/armor plate etc, with chuncks of balsa. Both are flat deck cockpits with not much room for more than just a pilot bust etc.
John
John