RCU Forums

RCU Forums (https://www.rcuniverse.com/forum/)
-   Twin & Multi Engine RC Aircraft (https://www.rcuniverse.com/forum/twin-multi-engine-rc-aircraft-192/)
-   -   NEW KMP 95" B-25 (https://www.rcuniverse.com/forum/twin-multi-engine-rc-aircraft-192/7060787-new-kmp-95%22-b-25-a.html)

Desertlakesflying 06-12-2011 02:17 PM

RE: NEW KMP 95
 
Use Sullivan flex tanks that will fit

tevans55 06-13-2011 07:59 AM

RE: NEW KMP 95
 
Junior55-

I noticed the same thing with mine. I never use the stock tanks with any planes because I have had 2 of them split around the neck. I bought 10 oz Sullivans for the DLE 20's. Still doesn't make sense that the stock tanks don't fit in our planes.

kahloq 06-13-2011 02:16 PM

RE: NEW KMP 95
 
My stock tanks fit fine, but i opted to use much larger tanks simply cuz Im using thirstly large radial glow motors. I used 24 or 26 oz graupner tanks.

p51tom 06-13-2011 05:19 PM

RE: NEW KMP 95
 
I just started my B25 and decided to make some changes right from the start. I wanted make the flaps more scale like and add spars to the center section. I removed the covering to make these changes then I will fiberglass the wing. After seeing F82Fan's broken center section I cut 2 additional plywood spars and will use a wing attachment set up used on the old Byron kits. Only one set screw will need to be tightened to attach the wing.
Great site, P51Tom.

p51tom 06-13-2011 05:21 PM

RE: NEW KMP 95
 
1 Attachment(s)
I am sending some photos. P51Tom

gunny11 06-14-2011 08:54 PM

RE: NEW KMP 95
 
Nice p51tom. I'll be following with interest.

Gunny

p51tom 06-15-2011 08:40 AM

RE: NEW KMP 95
 
1 Attachment(s)
I have a question about gas engines, props, and RPM. I going to use 2 RCGF 20CC in my B25. I have been breaking my engines in with a 10 pound Great Planes Revolver with a 16x6 Zinger wide blade prop. I am getting 7600 RPM and the plane flies great. I have 52 flights on one engine and I have just installed the second one. Before changing engines I decided to try some 3 blade props. F82Fan used 14X7X3 on his 24cc engines with great success, therefore I tried this prop first. I was gitting over 9000 RPM and the plane did not fly well. The engine seemed to be over revving with very poor prformance. I have run larger gas engines in the past (Q52 & G62) and the planes fly great at around 6000 RPM. I then tried a 15x7x3 prop with 7400 RPM and the plane flew fine. Will the plane fly with a 7 inch pitch a only 7400 RPM or should I try a 14x9x3?

Junior55 06-16-2011 07:15 AM

RE: NEW KMP 95
 
HI but together the same plane what gas tanks you used, because the ones that came with the kit are to long.

p51tom 06-16-2011 08:00 AM

RE: NEW KMP 95
 
I fly an 8 minute flight on my Revolver with the 20 CC engine 85% of the flight with the throttle wide open. I have around 3 oz. of an 8 oz. tank left. To be safe I plan on using a 10 oz tank by Pylon Brand model SS-10. It measures about 4" long, 2.5" wide, and 2" high and will be positioned on the right side behind the firewall. I have seen pilots with no trottle control and a large tank fly the model for over 30 minutes until the engine ran out of fuel. Very lucky that the bat. pack lasted longer.

Junior55 06-18-2011 05:10 AM

RE: NEW KMP 95
 
thank you. well it the 550cc this kit bring are 51/2" long and i only 5" so they to long. i also got 20s on my.

Eldher 06-18-2011 06:11 AM

RE: NEW KMP 95
 
p51tom,

Very nice work on the wing, like the flap detail very much.

I have also rebuilt the center section of my wing after it broke like F82Fan. NOTE that the failure is from _torsional_ loading on the wing when the gear hits (i.e. the wing twists). You’ll note looking at the wing design that it is only the thin sheeting that restricts twisting. I put cross braces in an ‘X’ pattern in the bays ahead of the main spar in _addition_ to fiber glassing the sheeting. I have since had several firm landings (one that bent the original ESM gear all to hell) and have not had another failure of the wing. BTW, I have since upgraded the gear to Robart.

Eldher 06-18-2011 06:16 AM

RE: NEW KMP 95
 
p51tom,

Can't answer your prop question directly, so I'll add my setup as a datapoint.

Running 16x8x3 MAS props, 8800 RPM, Saito 150 engines.
Plane flys great, lots of power and authority.

kahloq 06-18-2011 12:55 PM

RE: NEW KMP 95
 
With Eldher13's assistance, I also added the cross bracing in the center wing section. Highly recommend doing so.

tevans55 06-18-2011 03:07 PM

RE: NEW KMP 95
 
Eldher13-
What retracts and struts are you using from Robart?

kahloq 06-18-2011 04:16 PM

RE: NEW KMP 95
 
Mine has the robart 630 mains with the robostruts that come with it and the nose gear is robasrt 105 degree

Eldher 06-19-2011 05:25 AM

RE: NEW KMP 95
 
I have installed the folling Robart gear:
- 635RS 90 Degree Heavy Duty Mains
- Robart Straight RoboStrut 1/2"
- Disc Brakes For 4" - 4 1/2" Brake Ready Aluminum Wheels (pr.) (pt# 140)
- 4 1/2" Brake Ready Aluminum Wheels
- 641RS nose wheel retract, 110 degree
- RoboStrut 440/661 (7/16") for the nose wheel
- I am using the original ESM nose wheel


tevans55 06-19-2011 08:16 AM

RE: NEW KMP 95
 
I have not acquired my retract system yet however I am using a 5.5" robart main wheel/tire with brakes. If it is convenient, would you mind measuring the distance from the plywood retract mount to the center of your axle. A second measurement would be from the top of your main tire to the bottom of the nacelle. Thanks in advance for any help you are able to provide!

By the way, if anyone knows where I can get my hands on a "B" version tail turret from a 118" Ziroli B-25 I would be forever grateful. Ziroli does not sell these as a separate item and the whole glass kit is alot to pay for one turret. I may need to make one if I can't find one that will fit this plane.

Eldher 06-19-2011 02:11 PM

RE: NEW KMP 95
 

Measurements with gear down
- distance from the plywood retract mount to the center of axle: 7.0"
- distance from top of main tire to the bottom of the nacelle: 2.25"

NOTE: the RoboStrut length can be modified. If you use a 5.5" main, I would seriously consider shortening the main strut by 0.5" (my wheels are 4.5" dia).
Where you are most likely to run into clearance problems is inside the nacelle. I have approx 0.25" clearance between the top of the tire and the _inside_ top of the nacelle. Now if you shorten the main strut you get more room as the nacelle gets larger going forward. Don't know if there is enough room for a 5.5" tire.

tevans55 06-19-2011 03:01 PM

RE: NEW KMP 95
 
Thanks Eldher13. I've been working trying to determine what will work versus what is close to scale. Your measurements are very helpful and I hope I am able to make it work. Thanks again!

Eldher 06-19-2011 05:25 PM

RE: NEW KMP 95
 


ORIGINAL: tevans55

Thanks Eldher13. I've been working trying to determine what will work versus what is close to scale. Your measurements are very helpful and I hope I am able to make it work. Thanks again!
You're welcome. Let me know how else I can help.

tevans55 06-19-2011 06:02 PM

RE: NEW KMP 95
 
[/quote]

You're welcome. Let me know how else I can help.

[/quote]

Thanks again and I will probably have more questions as things progress. I am still waiting for the wheels to be finished from robart...they have already sent the brakes. I'm busy painting and putting panel lines on right now. I will try to post some photos also after I get a little farther down the road. Thanks again for your help.

p51tom 06-20-2011 03:30 PM

RE: NEW KMP 95
 
1 Attachment(s)
I am using Byron 5.25 inch wheels on my B25. The hubs are very much like the real aircraft with many holes around the edge of the wheel. I had a set of gear for a Wings B25 that I decided not to build. They are Century Jet gear which fit fine but I may need to use a stronger spring for the mains.

Eldher 06-20-2011 07:16 PM

RE: NEW KMP 95
 
p51tom ... look awesome!


tevans55 06-21-2011 04:37 AM

RE: NEW KMP 95
 
I have another question related to the ignition setup. My question is...will it matter if I run both ignitions through the same 2500 mah Nicad. The ignitions would have individual switches with separate leads from the same battery. Each engine will have a servo for the throttle and a servo for the choke. Thanks for any help.

P51Tom-
That does look like a good setup...all of my planes have CJ retracts, I have found them to be very durable with the standard care and cleaning every so often.

p51tom 06-23-2011 12:04 PM

RE: NEW KMP 95
 
1 Attachment(s)
I have added the outer wing panels with the Byron method of holding the wing on. All that needs to be done is to tighten or loosen one bolt on top of the nacelle for each panel. I also used larger dowels to line up the outer wings. I will modify the outer flaps and add landing lights then I can resheet the wings and fiberglass them like the center section.


All times are GMT -8. The time now is 11:21 AM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.