RE: KMP B-25 CONSTRUCTION.  
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RE: KMP B-25 CONSTRUCTION. - 3/20/2005 1:16:18 AM   
samparfitt


 

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From: West Chester, OH, USA
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Retracts (continued).
Well, I'm a much happier camper tonight.
Figured that since the retracts have lots of slop, I might as well take them apart.
I lucked out and was able to fix them.
It turns out that the distance of the back wall (one with the air cylinder) of the retract mechanism to the side walls(casing) determines how loose the retracts move in the down position.
There is a very thin piece of material between the back wall.
I removed it and the back wall is thus closer to the side wall.
This allows the retract 'guts' to rest closer so the slop is removed.

First picture:
Here's the back wall with the air cylinder cover removed.
That center brass shaft screws into a brass rod on the other side of the wall that moves the strut up and down.
The brass rod in the middle of the spring and the brass rod on the other side were not screwed tight to each other on both main retracts (haven't done the nose yet).

Second picture:
This is the end view of the end wall from the other side.
In the middle is that brass rod that moves the retract up and down.
To the right is the piece of material that I removed from the end wall.

Third picture:
You can see in this picture where the retract mechanism rests on the back wall (those two squares are where
the mechanism rests on the back wall).
I put her back together and the slop was gone.
The other main still had some slop so I filed (very, very little filing) the end of the side walls.
This, as mentioned before, allowed the end wall to be closer in so the slop is taken out.
note that the end wall has a top and bottom, the air cylinder is a skoch closer to the bottom than the top.
The screws probably won't go in if you put it on upside down.

Fourth picture:
I wasn't happy with that 'heavy' air line so I converted it to Robart's air lines.
The Robart's air line's diameter is too small to fit over the large nipple of the kit's air tank so a transition is needed.
Use Robart's in line #217 part to do this.



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< Message edited by samparfitt -- 3/20/2005 2:13:50 PM >


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G. Samuel Parfitt

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       Post #: 76

RE: KMP B-25 CONSTRUCTION. - 3/20/2005 1:20:07 AM   
samparfitt


 

Posts: 1744
Joined: 9/1/2002
From: West Chester, OH, USA
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Retracts (continued)

First picture:
With the large 1/2" struts, it moved where the wheel retracted into the well so I readjusted the mount.

Second picture:
Retract cover added.
You can see where I had to trim the cover so the wheel and strut would fit.

Third picture:
side view: the trimming is not noticeable from the side.

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G. Samuel Parfitt

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       Post #: 77

RE: KMP B-25 CONSTRUCTION. - 3/20/2005 1:22:41 AM   
samparfitt


 

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From: West Chester, OH, USA
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Throttle and fuel tank.

First picture:
Throttle servo connected.
I had to grind that corner off the muffler so the clevis would not rub it.

Second picture:
I had to cut a larger hole in the fire wall so the fuel lines could easily 'flow' out to the engine.
Also, had to cut two of the bolts shorter so they wouldn't rub against the tank.

Third picture:
Gettin' there!

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< Message edited by samparfitt -- 3/20/2005 2:09:04 PM >


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G. Samuel Parfitt

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       Post #: 78

RE: KMP B-25 CONSTRUCTION. - 3/20/2005 1:49:07 AM   
akflyer



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Joined: 1/24/2002
From: Soldotna, AK, USA
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For your Flap hook up at the servo, you may take a look at this. this would allow your flaps to drop the same distance and would be a VERY easy install.

http://www.hobby-lobby.com/pushrods.htm

Joins 2 pushrods to 1 as on a split elevator.
GR9034 Triple Rod Connector ..... $ 7.90
IN STOCK
A machined fitting that is about 1/2" long, in which are three holes for pushrods and holes for Allen set screws. It can be used for such linkages as a single pushrod from a servo connected to split elevators, or to flaps, or from dual servos to a boat rudder.


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RE: KMP B-25 CONSTRUCTION. - 3/20/2005 6:05:23 PM   
Idigbo


 

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From: Stafford, UNITED KINGDOM
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On my B25, I also didn't see the need for 4 flap servos. I used the two inner flap servo bays, and connected the outers to the inners using 4mm piano wire, like an elevator joiner, run through the nacelle. Glad you all seem to be modding the retract plate so you can fit the wheel on the outside of the leg, shame it wasn't done in the factory though for you guys. On the ones we get over here, they will come with this improvement! Thats what you get for having the first lot out of the factory!!! Those struts you are using look the business. Are you all going with the forked pushrod?

Ian.

(in reply to akflyer)
       Post #: 80

RE: KMP B-25 CONSTRUCTION. - 3/21/2005 4:51:00 PM   
samparfitt


 

Posts: 1744
Joined: 9/1/2002
From: West Chester, OH, USA
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Fuse cover (continued).

First picture:
I think it'll be very difficult to glue that cover on and then expect to tighten 4 bolts through a 4" deep hole.
I was going to use door latches to hold the cover on (like on my Mustang) but the cover is so deep,
I'm opting for traditional screws to hold it on.
(I prefer the door latch as it's quick and there's no screws to drop in the grass).
In the picture,
at the top is the Mustang air scoop with the door latches.
Below that is the 4 triangular pieces of bass wood that I'll be using to hold the fuse cover on.
Left is the fuse cover.

Second picture:
The bass wood is glued in.
A jeweler's or small screw driver or allen wrench will be needed to put the screws in
since the two nacelles are close to the fuse.
Notches are also needed on the base of the fuse cover.


Cowls (continued)
Third picture:
The cowl ply former has been epoxied and glued in.
I cut excess ply away for good air flow.
The manual has the ply formers glued to the cowl (take your pick).
I still need to cover the formers with epoxy to fuel proof them.

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G. Samuel Parfitt

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       Post #: 81

RE: KMP B-25 CONSTRUCTION. - 3/21/2005 4:52:38 PM   
samparfitt


 

Posts: 1744
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From: West Chester, OH, USA
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Guns

First picture:
I drilled and filed holes in the fuse and slipped the entire gun in from the inside.
I'm using the whole gun so I have more to glue to so the gun is less likely to get broken off.
A little tape and balsa to hold the guns in place while they are epoxied.

Second picture:
I mixed up microballs with the epoxy so it wouldn't flow off the guns while it was drying.
Had some left over and slopped it on the fuse formers for extra strength.

Third picture:
I used bathroom silicone caulk to hold the side guns on.
You can see the caulk on the inside of the opposite gun.
I figured these would get bumped so I wanted the guns to give without damaging the fuse.
The caulk never hardens so this should work.
I used GE's 50 yr silicone.
Masking tape is on the one gun to keep it from falling out until the caulk dries.

Fourth picture:
'Glass' windows installed.
I used #2 button head screws.

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< Message edited by samparfitt -- 3/21/2005 5:08:33 PM >


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G. Samuel Parfitt

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RE: KMP B-25 CONSTRUCTION. - 3/21/2005 4:55:14 PM   
samparfitt


 

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From: West Chester, OH, USA
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Canopies (continued)

First picture:
Nose and cockpit canopy.
Used button head screws at all the main brace intersections.
(I just noticed that two of the paint 'bracings' on the cowl stop in the middle of the nose).
(looking at the prototype, it looks like a brace should be going horizontally across, perpenticular, to support them)

Second picture:
Front view.

Third picture:
Tail end.
I also used caulk to hold the guns on as they will probably be bumped.
I used laquer thinner and lots of rubbing to get the paint off the back of the tail gunner's canopy.
This paint is so durable that they must be using a two part epoxy paint.
Very durable but also very toxic when spraying it.

Fourth picture:
Dorsal canopy.
This canopy is very fragile and is going to get crushed sooner or later.
I'm going to cut two ply formers and glue those in.

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< Message edited by samparfitt -- 3/21/2005 5:16:33 PM >


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G. Samuel Parfitt

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       Post #: 83

RE: KMP B-25 CONSTRUCTION. - 3/21/2005 4:56:21 PM   
samparfitt


 

Posts: 1744
Joined: 9/1/2002
From: West Chester, OH, USA
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First picture:
Wing is done.
Well, almost: have to drill/tap a pressure nipple on the muffler and fuel proof the cowl ply former.
Fake radial engines are in with 14X7 3-blade props and spinner nuts.


Almost done: Still have to work on the 'play' in the nose retract and steering and arrange battery/ receiver & on/off switches.

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< Message edited by samparfitt -- 3/21/2005 5:04:51 PM >


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G. Samuel Parfitt

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       Post #: 84

RE: KMP B-25 CONSTRUCTION. - 3/21/2005 7:10:46 PM   
Idigbo


 

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From: Stafford, UNITED KINGDOM
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Sam, the belly pan on my Mitchell is held on with two Hatch Catches, one at the front and another at the back, both on the centreline of the fuselage. They are both fixed into the belly pan, and slide forwards and backwards to locate into the fuselage at front and rear. Beauty of doing it this way is that it goes back onto the fuselage even when the wing aint on, and takes 2 seconds and no tools to fit or remove. Handy on mine as the reciever is mounted onto the bottom of the wing, so all wiring is accessible with the model assembled. I'll take a pic of the set up if I have explained it badly, but it is worth doing as trying to screw the belly on without breaking guns off the front, rear, top and sides is fun to watch (if not to do) to say the least!!!!

Ian.

(in reply to samparfitt)
       Post #: 85

RE: KMP B-25 CONSTRUCTION. - 3/21/2005 7:16:01 PM   
samparfitt


 

Posts: 1744
Joined: 9/1/2002
From: West Chester, OH, USA
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Ian,
Sounds like a good idea.
I've got a couple BVM jet release ones in my parts box.
Need pictures and who makes yours.
thanks,
Sam

< Message edited by samparfitt -- 3/21/2005 7:17:46 PM >


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G. Samuel Parfitt

(in reply to Idigbo)