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ASM F-7F Tigercat

Old 11-21-2009, 12:39 AM
  #26  
grunta
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Default RE: ASM F-7F Tigercat

Hi Brad,
Sitting back here just looking sounds as if it is going together without to many problems . l have same model but still tossing up about motors 75ax or 81 fs .how far off is the maiden flight ? As soon as l decide on the motors l will start building it .

Regards Rod.
Old 11-22-2009, 01:01 AM
  #27  
Brad330l
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Default RE: ASM F-7F Tigercat

Hey grunta, welcome mate, yes you will have no problems putting this thing together as long as you follow a couple of critical steps in the destructions (like building and fitting elevator actuating rod into fuse before gluing in tailplane). I like doing thing my own way as we all do but I still read the instruction booklet a couple of times and refered back to it on occassion as well. The biggest thing for me was doing most things twice!!!!!! Well it is a twin.

It had its first outing today as I took it down to the field to show the guys. This was a transport and assembly tryout as well and all went according to plan although initially I thought I would have to get myself a bigger four wheel drive [X(]
I can however transport it complete except for the outer wings so putting it together down the field is a cinch.

Rod, I went for two strokes as I want the screaming RPM and sound you get out of a finely tuned engine through a basically unmuffled exhaust. My .61 through a pitts in my Midget Mustang souns great and I want that times two. I have watched an ASM tigercat on youtube with .70 FS's and it was not what I was after. He may have been at half throttle but it just didnt cut it for me.

The maiden is hopefully next weekend if my exhausts arrive from Towers. I'll let you know.
Keep us informed of you progress.

Cheers,

Brad
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Old 11-23-2009, 08:05 AM
  #28  
Brad330l
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Default RE: ASM F-7F Tigercat

Well guys after the time out in the sun the covering on the Cat looked far from impressive. The factory obviously did not heat the covering enough when applying it so I had to spend a good half hour going over the wings and tail surfaces with my sealing iron and hot mit. The worst thing was that the factory did not overlap the covering at all on the wing striping so while using the least amount of heat possible to get rid of the wrinkles the edges of the green shrunk in and exposed the blue underneath. Also the yellow lettering is very soft and I melted the 'N' at the edge. Once again not pouring too much heat into any one spot. So beware!!!!!!!!!!!!! After the covering looked good I applied the stars and bars. I used a string line accross the wing to get a nice straight angle for the sticker.
The cowls are now mounted and even though the rubber gromits/washers I am using look a bit rough they are servicable and hold the cowls in place nicely. I will get some dome headed screws that will look a whole lot better. I used a straight edge to get the cowls nice and even.
Also made the fill valve mount for the retracts out of 3mm five ply and mounted it to the wing. That called for more retract testing and pressure recording. I can only pump the system up to 44psi at the moment as I am using the pump that came with my baby's pram but with this pressure I can get a full cycle. At 90 to 100 psi I will definatly need to use the Robart air restrictors I have in the air lines or I will wreck my retracts as they will slam up and down too fast. I have left the system tonight with 44psi in it as a pressure leak down test. Hopefully tomorrow it will still have pressure. I'll report on the results.

Cheers,

Brad
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Old 11-24-2009, 08:59 AM
  #29  
Brad330l
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Default RE: ASM F-7F Tigercat

Tonight I nutted out the nose gear door mounting. I read the instruction booklet regarding mounting it again but as soon as I started I could see problems so I took my time and had a good think about it. Firstly the instructions state to notch out a bit of the door to allow for the pivot part of the hinge. This I did. They say to glue the hinge along the bottom inside of the door and this is the first problem. Like this the center of the hinge (hinge line) is too deep inside the door line so fouling will result. I drilled the hinge a 45 deg angle hole in the block in the door so the hinge line could be just outside the door line as in the picture. The hinge is drilled at 45 deg through a block in the fuselage and this I worked out to be a little further forward that what the instructions suggested. I actually didnt go far enough and you can see the resulting gap. It is not a bad fit but not perfect. My advise,,,, take youe time. So the door is mounted. Time to attach it to the retract leg with the already fitted wire door actuator but there is no attachment points provided in the kit to glue to the door for the wire to go through. I have some angle styrene stock that I cut to length and glued onto the doors for this purpose. I was lucky to make it long enough to be able to drill another set of holes for the wire as my first attempt was too far away making the wheel just clear the door when extended but hitting it when the oleo started compressing. I would make the angle longer next time and drill a fer sets of matching holes for adjustment. Even with this mucking around I still had to bend up a new door actuating wire as the one in the kit ended up being about 3mm (1/8th) too short. Extended the door was still too close to the wheel and retracted the door was fully closed before the retract had seated into a locked position. Not sure if it was something I did wrong but the longer wire I bent up did the job. The whole thing is a bit of a strange set up because as the wheel steers it twists the door on the hinge. I think the wires are meant to pass through the holes in the mounts but this just aint going to happen. Maybe bigger holes???
Anyway it is done now so I will see how it goes.

In the picture you will see the Cat's newly painted pilot. I think the guy who painted him in the factory must have been on drugs. The pilot had a bright red leather helmet, yellow collar, red buckles and eye brows a drag queen would be proud to have. I slap of paint fixed him. Not the greatest of pilots but he is some thing in the cockpit.
Hopefully tomorrow I will get my exhausts and bits and pieces from Towers.

Cheers,

Brad

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Old 11-27-2009, 09:37 PM
  #30  
Brad330l
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Default RE: ASM F-7F Tigercat

Right guys, the Cat is pretty much done now except for exhausts and main gear doors. The exhausts got posted from Towers on the 23rd so I should have them next week some time. When they arrive I need to mount them (obviously) ,cut the cowls to suit the pipes, and also drill a hole for the needle valve extention at the same time. I will then be able to balance it all.
In the mean time I will be making 'C' type hinges for the main gear doors and getting them working. That is going to be fun as it will all be trial and error. I have put the door actuating plates together with the front hinge and pivot wires that conect to the doors. In my kit the main wheels hit the underside of the wing when retracted so I will need to reduce the diameter of the wheels by about 3 to 4mm to acommodate the thickness of the stiriker/actuator plate. No biggy there,,, just sand them down on a drill.
The fuel tanks I am using are bigger than the kit supplied ones so I had to widen the the tank deck a bit for the cable tie to be able to hold the tank down properly. You can see the notches in the added ply to locate the ties. With this and some double sided tape these tanks are not going to move about. I was going to wrap then in foam but thought I would try the kit suggestion of the tape. If I have any running problems at all the first thing I will do is wrap them.

I did a bit of a cockpit, my aim was to just get some colour in there and have a pilot. That was it.
Made also a simple aerial attachment bracket for the tail. The wire in between the bracket and elastic band will be remade neater.

I went through everything and lock tighted, glued, tightened and strapped down, so all is (almost) ready.

Cheers,

Brad
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Old 11-29-2009, 02:14 AM
  #31  
Brad330l
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Default RE: ASM F-7F Tigercat

Ok gents,,, I had a change of mind after looking at making 'C' hinges (all too hard) and getting a reply off John (who flies this ASM Tigercat)

http://www.youtube.com/watch?v=OqApJlzbuT0

about the hinging of the main gear doors. John said he did his as per the kit instructions and left a 5mm gap and they work fine.
So, I took another look and took some measurements and decided to give it a go. In the pictures, the first one is actually hinged but at the start this was what I was looking at, the distance between the door and the nacelle. The second picture shows the extra mounting blocks I added inside the kit fitted ones to accomodate the new hinge position. The next lot show how you need to file away (as per instructions) for the pin hinge. I made sure the pivot point wes outside the edge of the door and that the hinge was not showing below the flat surface of the join between the door and the nacelle. Next is drill into nacelle and these holes need to be as per instructions right at the edge. I drilled mine in at a slight angle so the hinge went more into the center of the mounting block. So all that went pretty well.

Now these wheels hitting the underside of the wing when retracted. Instead of reducing their diameter I cut a clearance hole in the sheeting that ended up just in front of an internal stiftner. In the pictures you can see how high the gear doors sat before the clearance hole. The the door actuating plate would have to sit on top of that!!! Not good.
So I redesigned the plate so it had a hole in it too for the wheel to go through. I kept the same lengths etc for the plate so they were in their proper spot when glued in. So now the doors close fully and I can open them as far as I want too. They are all glued in with 30 Zpoxy and fiberglass powder and the actuators are all in too. Just have to conect the wire from the plate to some control horns fitted to the doors. I'll let you know how I go there.

Hope all that makes sence.

Cheers,

Brad


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Old 12-08-2009, 06:33 AM
  #32  
Brad330l
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Default RE: ASM F-7F Tigercat

Hi Gents,
I received my exhausts today and straight into the shed I went with camera in hand.
The exhausts are a perfect fit!!!!!!!!!![X(][sm=thumbs_up.gif][sm=thumbs_up.gif]
I had the Jtec mufflers on pre-order and knew I would need the OS 15mm exhaust extentions with gaskets as well and it all turned out real nice.
The front outside of the exhaust is so close to the cowl but does not hit it. One throttle push rod has nice clearance from the back of the 'box', the other will need a tiny adjustment. This seems to be the perfect fit out. I just need to drill out and tap for a pressure nipple (not supplied) for the fuel tank.
I will be running the engines this week end and doing taxi tests.
The front on view looks as thought the exhaust is too big but that is just the way the camera lies.

Cheers,

Brad
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Old 12-08-2009, 11:30 AM
  #33  
Capt G
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Default RE: ASM F-7F Tigercat

What is your mechanism to open and close those gear doors?
Old 12-08-2009, 06:13 PM
  #34  
Thunderbolt47
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Default RE: ASM F-7F Tigercat

Hey Brad, Will those engine run OK with two outlets? (reduced pressure). I know that has been a problem with glow engines.

Looking good BTW
Kelly
Old 12-09-2009, 03:35 AM
  #35  
Brad330l
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Default RE: ASM F-7F Tigercat

Capt G the mechinism is a bit hard to see in the picture but basiclly the front is hinged (brass) and actuating wires extend out to the doors and the spring helps open and keep open the doors. The plate is sitting off the bottom of the wing about 15mm in the open position in the picture. The big hole you see is a neccessity to allow the wheel to retract far enough into the wing and lock properly. The wheel now hits the back of the hole to shut the doors. I had to do the actuating plate and the wing sheeting. I might glue a patch/stiftner on the inside of the wing for peace of mind so no strength is lost.
Thunderbolt47 all I can say is that the exhausts were designed for the engine so hopefully they will provide enough pressure for the tank. I'm sure they will as the holes are only 10mm (.400") each and my OS61 has a simular set up and works fine. No worries at all.

So, off to cut into the cowls and add some tubing to extend the exhausts out.

Cheers,

Brad
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Old 12-12-2009, 07:15 AM
  #36  
Brad330l
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Default RE: ASM F-7F Tigercat

The exhausts are all plumbed up and mounted. I drilled and tapped for the pressure nipples I took out of the stock OS mufflers.
The right hand side throttle pushrod has been modified so it does not touch the exhaust so it is all systems go for first engine runs and taxi tests tomorrow.

Cheers,

Brad
Old 12-14-2009, 04:13 AM
  #37  
Brad330l
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Default RE: ASM F-7F Tigercat

Well guys I have some good and some bad to report after the week ends effort.[:'(]
The good thing is that I got to go down the field and run my engines. They both started after a couple of flicks and ran no worries at all. I could not however richen them enough to four stroke at full open throttle as the run in instructions say they should. They kept on wanting to peak out so I got them four stroking at about three quauter throttle. I also stopped and started them a few times to allow to cool.
These things have a lot of power!!!!!!!!!!!!!!!!!! I took out the inline filters I had as I thought they might be restricting flow of fuel but this was not the case.

Now the bad. While running said engines the right hand side main undercarrage leg decided to collapse.[X(][:'(] It stopped the engine quite quickly as the prop dug intot he soft grass. (no damage there) but it also snapped one of the gear door hinges. Bugger!!!!!!! It appears I have a very large air leak as when I pump up the system again I can see the pressure needle slowly arcing down to zero. Man, this system was perfect at home!!! What might have happened is that I may have cut into an air line as I was drilling into the firewall as I was doing some throttle linkage adjustments. I hope that is it otherwise it could be a big investigation to find the leak. That side I worked on was the one that collapsed so heres hoping.
OK no biggy, I am determined to run a whole tank through these things so I cable tie the gear down (all) and tape the door so it wont rip off and run the rest of the tanks. Cool, done , but no taxi tests.

So I am on night shift Sunday night and need to do some Xmas shopping with the wife so I race home (late) and do that. Now I must unpack the model before I go to bed and while removing it from my four wheel drive I hear an almighty 'crack' as I do some internal damage to the tail mounting to the ply skeleton. Bugger!!!!!!! I will have to cut a couple of maintenance access hatches/holes and run some Zap down the joint.
So, some good, some bad.

Cheers,

Brad
Old 12-20-2009, 04:51 AM
  #38  
Brad330l
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Default RE: ASM F-7F Tigercat

Well Guys I carried out the required repairs including the air leak, gear door hinge and suspected cracked rear end. I also drilled out the Robart air line restrictors with a 1/32nd drill to get a bit more of a positive retraction of the main gear (only) so the gear doors have more of a chance of closing.
So the air leak[:@] turns out it was the nipple from the tank that was loose. NOW,, I must state that it was not the tank supplied with the retracts!!! I changed tanks because I had a shorter, fatter one that seemed to fit better on top of the wing the way I positioned everything. So I mixed up some 30 minute and fiberglass fibers and glued it just like the ASM tank is. NO LEAK NOW

The gear door hinge was simply Dremeled out and replaced.
The dremel came in handy at the tail too as I made a couple of 1/2" square holes to drip some Zap into. This fixed the broken tail instantly and I simply cut out some 'panel hatches' out of styrene sheet, removed some paint from the area and glued them on with Tamiya plastic model glue thus melting them together for a nice strong join.

So I got to run the engines again today down the field. I put almost two tanks through and called it a day.
Next week I will taxi and fly.
I came home and cut the cowls (works out when I went to bolt them on they needed clearence for the exhausts). I extended the needle valve wires another inch for easier operation and cut the pipe exits as well. Now all I need is some pipe extentions and carry out CoG checks and I can fly it. Cool.[8D]

Cheers,

Brad
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Old 12-20-2009, 08:06 AM
  #39  
Brad330l
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Default RE: ASM F-7F Tigercat

HA!!!!
[sm=red_smile.gif]Just realised I need to make a couple of holes for the glow driver as well!!!!!!!!!!!!!!!

Brad
Old 12-26-2009, 08:54 AM
  #40  
Brad330l
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Default RE: ASM F-7F Tigercat

Test flight tomorrow.
Tonight I made some dummy engines and cut out a cooling duct for the head of the OS 75. I made some baffling as well to go either side of the head nice and close to the fins. Now all the air getting sucked out of the cowl will have to go through this hole so I should get some decent cooling. This will do until I get my vac formed ones from Tower Hobbies.
The way I did it I can easily assemble and pull it all apart. The 'engine' is located by the crank case and carby and when the cowl goes on it holds it all in place. Simple and easy.

I did the CoG as well and ended up needing to add 206 grams (7.25oz) of lead to the nose for a nice balance at the forward position. I made sure I had the retracts tucked away as they arc rearward when up.

Put an elastic band in place to pull the nose wheel stearing wires out of the way when it retracts and did another pressure test on the system. I still have a small leak some where but it is very slow so I will get a full cycle for a flight. I imagine eight or so minutes will go very quickly for a test flight.[sm=bananahead.gif][sm=spinnyeyes.gif]

I'll let you know how it goes.

Brad
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Old 12-27-2009, 12:15 AM
  #41  
Brad330l
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Default RE: ASM F-7F Tigercat

IT FLYS GUYS!!!!!!!!!!!!!!!!!!!!![X(]
AND IT DOES IT WELL!!!!!!!!!!!!!!!

After running and tuning the engines and setting the idle mixtures I was happy enough to taxi it around. It works out the idle mixtures were way too rich as set by the factory, that is why I was having transition problems when advancing the throttles.
The nose wheel needed a bit of trimming and the model is really affected by power application on the ground. That is what rudder is for right. I did some high speed taxis and then came in to refuel and have a drink to settle the nerves (over 40 degrees C at 1000 Hrs and climbing).
So, the cowls are off for tuning so they are staying off for the test flight.
Here we go, power up and the cat is tracking well, nice throttle transition and up about 3/4 throttle and slowly advancing while feeding in more,,,, and more,,,, and more elevator until about a good 100meters of (longish) grass has been used up and then the nose gracefully left the ground in the most scalish type manner I could have hoped for. The nose is heavy!!!!!!!!! and I am climbing away now at full throttle holding about 1/5th stick. It wants to go slowly right so I let it as this was my planned climb out any way, 180 turn and I am in control and coming down wind pull the gear up,,,,,, ah, thats better, trim sorted.( a couple of clicks up or down I cant remember) now two clicks of left aileron and I am away. The cat is a *****. The low rates I had set were perfect. I do believe however that the CoG can come back a bit as I lost a bit of height in the turns but I will be evaluating this again (obviously) when further flight takes place. It is fast, even at 3/4 throttle and 14X6 props I was zooming around the sky so I hope Baz got a couple of pictures as proof to what I'm tellin' you. I had one gear door hanging down and when gear down was selected after slowing down for landing my fears were well founded as the nose just hung half way not locked in. No flaps for landing. I was going to switch to high rates on finals because of the take off but (quickly) decided to leave all alone as I was a bit busy and all looked good as it was. The last thing I wanted was to balloon as well with too much input and get slow and tip it in. So flying down the path I needed to add a bit of power to get me to the nice longer grass and the cat took it all in stride and behaved perfectly all the way down to a nice mains touch down with full up elevator with the nose sliding easily on the grass. When we walked over and picked the nose of the model off the grass the nose gear locked down. (like hey whats the problem here)
The only damage was a styrene bracket came off the nose gear door for the retracting/support wire.

Man I am so happy. This is my first twin and it has been a great experience so far. I am looking forward to many more exciting flights with this model improving every time.
What a beauty.

Pics and vid (short vid) to follow if Bazza got some.

Cheers,

Brad
Old 12-27-2009, 12:51 AM
  #42  
grunta
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Default RE: ASM F-7F Tigercat

Congradulations Brad looking forward to seeing the pic's and vid . l have started putting mine together with same motors . Congrads again .
Regards Rod
Old 12-27-2009, 07:16 AM
  #43  
Brad330l
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Default RE: ASM F-7F Tigercat

Cheers Grunta, after today I would have to say you made a great choice with the 75's. I cant wait to be properly run in and using some big props to get some serious speed.

Here are a couple of pictures from today. All I have i'm afraid. The rest and the vid are unusable.[],,,, hey,,, I was the one flying.

Cheers,

Brad
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Old 01-02-2010, 03:17 AM
  #44  
Brad330l
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Default RE: ASM F-7F Tigercat

Ok Gents, I have done some repairs to the nose steering, fixed the gear door and found the air leak in the retract system. It was the fill valve!!!!!![:@] Well a bit disappointed but it was an easy fix as I had a replacement from another set. I will pull it apart when I can find the right tool and give it some rubber grease to see if that will fix it for further use.
Also I found the elestic band I had connected to the steering wires to drag them out of the way when the wheel retracts was too tight so I totally rerigged that and now it will not hinder the nose wheel coming down into the air stream.
I did a final weigh-in as well for the heavy model documentation and it comes out to 8.86Kg (19.49 lbs). That is a bit more than the instructions state it should weigh with the retracts installed at 7.7Kg (16.94 lbs). It still flys nicely at this weight though.
I have installed some 13x8 props as my 14x6 wooden Master Airscrew ones didnt survive the long grass and split to the point of unservicability. These new ones were the only ones avaliable in town from my flying mate so beggars cant be choosers. No hobby shops anywhere near here guys!!

If this 15/20 kts of dry, sapping oven hot wind stops tomorrow I will get another flight in. If not it will be do some more little bits and pieces to the bird.
Heres hoping.

Cheers,

Brad
Old 01-02-2010, 08:32 AM
  #45  
Brad330l
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Default RE: ASM F-7F Tigercat

Just redid the CoG on my home made CoG machine and ended up removing 54g (1.95oz) from the nose. (From a total of only 206g added) This puts the CoG just behind the forward most limit of 85mm behind the leading edge at the root of the wing. After my first flight I feel confident this change will not be exessive and will make the model even easier to fly.

Cheers,

Brad
Old 01-10-2010, 08:37 AM
  #46  
Brad330l
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Default RE: ASM F-7F Tigercat

Got the second flight in on the Cat guys.
It was a beautiful day with full overcast and nice constant breeze at 10kts.
I tuned engines again with exhaust mods done and attempted a flight with cowls on but the engines overheated quite quickly and I had to abort a take off. Cowls removed solved the problem as you can see with the following vid. I will add to the flight report later as it is getting on now and bed is calling.
I still have a pesky air leak and as you will see. The nose gear does not lock down and I hold the nose high during the landing.
Thanks Eric for taking the film on my camera.

http://www.youtube.com/watch?v=BBthlrQZa94

Cheers,

Brad
Old 01-10-2010, 08:53 AM
  #47  
Thunderbolt47
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Default RE: ASM F-7F Tigercat

Brad, I'm glad the muffler mod worked.

Looking at your baffle pic from above, it looks like the inlet air is fine. How much outlet air do you have?

BTW really nice flight
Kelly
Old 01-10-2010, 06:34 PM
  #48  
thonnor
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Default RE: ASM F-7F Tigercat

Top marks Brad - nice flight!
She looks very stable and 'locked in' in flight. Landing looked quite effortless too .... was that without flaps?
Shame about the nose retract problem. Are you sure it's an air leek or could it be the front gear door causing too much drag? I've seen that people are leaving the door off of the YT International F7F perhaps for that reason?
Hope you can get the cooling issue sorted. The air exits in the cowl are not very big .... did you cut extra exits in the bottom of the cowls?

Work on my Cat has started at last so it should up and flying by the spring here in the UK.

Once again mate ... congrads on a great job on a great plane [8D]
Old 01-11-2010, 05:20 AM
  #49  
Brad330l
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Default RE: ASM F-7F Tigercat

The flight was great guys. I was actually shaking a bit (a bit ) but the Cat was rock solid and really in the groove. It has no bad habits at all that I can pick and with a bit more fine tuning I hope to be able to have some great flying with it.
With the CoG moved back that little bit the Cat was obvously not so nose heavy with the gear down so trim changes were a lot less than the first flight. This was more noticable when I went gear down as after take off I was climbing and put the gear up pretty soon after leaving the ground. I was back to about 3/4 throttle for most of the flight and I helped the nose around the corners with a bit of rudder input making nice co-ordinated turns. If you look at the video at 4.30 minutes you wil see the Cat pitch down. This is when I tried the flaps with the down elevator mix. Even with such a small amount the model wanted to head down in a hurry. I was going to adjust in flight but when I took a quick look at my TX I had some how gone off the screen I needed. So yes, no flaps for landing.
The cowls do have semi open cooling doors on either side and at the bottom as well as about a 3mm (1/8th) gap all the way around the circumference but I will have to open them up a bit more as well as open up the inlets a bit more while still trying to maintain the 1 to 3 ratio in/out.
Yes this air leak. I will need to pull every thing out of the nacelles and investigate. While I am there I will rip out two very tempromental Du-Bro in line fuel fill valves as the 'O' rings seem to have expanded so the fill nipple is very hard to seat when I want to fill and when full and the nipple removed the button does not seal. Others have voices their concerns about using these things and now I am with them. I have used them in the past with no worries but these one were crud from day one. So a dedicated fill line with fuel dot will be used.
I am going to give the nose gear door one more chance. I will investigate the air leak and remove or drill out the air restrictor in the nose tubing to get a more positive action. If this doesnt work then off it will come. At least I know I can land the thing with no front wheel down.
So there is a bit more work to do but less than last time

Cheers,

Brad
Old 01-24-2010, 12:51 AM
  #50  
Brad330l
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Default RE: ASM F-7F Tigercat

WOW GUYS,,,, FLIGHTS 3 & 4 WERE GREAT!!!!!!!!![8D]

Through the week I pulled the Cat right down (almost) and fixed what I thought needed doing to get a more reliable and better functioning model.
I ordered my required spares from Discount Hobbies here in Western Australia http://www.discounthobbies.com.au/catalog/ and two days later had them in hand.
First off was to remove those pesky fuel valves and replace them with fuel dots made by the Ming Yang Model CO.,LTD.
I laminated a couple of pieces of styrene sheet and glued it to the fuselage over the existing hole for the valve. I had the tanks right out to replumb them and pressure test them so they were soon back in place. While the right tank was out I made a new throttle pushrod and made it so I have a clevis on the actual carby arm so I have got some adjustment external to the hidden in cowl servo. I had to do this as I am using a 'Y' lead for throttle forcing myself to set the two engines up mechanically as close as possible. I was then able to tweek the low end carby position on the right engine to match that of the left after the Cat was back together. Cool. That done it was time to remove the retracts and pressure test them. (Dunk them in a bucket of water) This actually showed that none of the cylinders were leaking so I looked a bit more closely at the air hose near the valve and tank as decided to replace the kit supplied clear tubing with Robart tubing. I did this after quite easily pulling a kit supplied tube off one of the cylinders and thought "this is not right" Now I have no air leak!!!!!!![sm=thumbs_up.gif] In an attempt to get the gear a bit more positive in action I drilled out the air restrictors with a 1/32nd drill. Another thing I found was that the main pivot pin in the gear legs was loose and was working it way out of the units!!!!!!![X(][:@] This was easily fixed by using a center punch and dimpling the pin in three positions and then tapping it home into the brass bush where I hope it will stay.
While at it all I replaced the throttle servo leads with longer ones so I can get the nacelle further away from the wing during maintenance and I replaced the gear mounting screws with bolts and blind nuts.
The last thing to do was fit my new 14x6 Master Airscrew props after balancing. With these I got 10400RPM richened to 10050 or so for run-in.
The first flight was really another test flight (arn't they all) nice take off and gear tucked away nicely the Cat needed a couple of clicks down and two right and it was tracking well. One thing I have found through the flights is that need to retrim through different phases,, just like a real one ay? The engines were running sweet and I wasn't even shaking so I went for a barrel roll and no worries there!! There's one sign off.
After some fun it was time to try the flaps and at the first stage down (with gear down and reduced air speed) I found there was no ballooning or diving. Great, that is dialed. At full flap the Cat wanted to nose high a bit so I needed to adjust that when on the ground. Time for a landing and another greaser it was. Awesome.
Flight two was started with some flap set for takeoff and man what a difference that made. It reduced the run by about a quarter and it still climbed out with authority and as stable as. Gear up flaps up and fun time with some high speed passes but mostly 3/4 throttle to continue running the engines in and get that beautiful harmonics and scale speed at height. Flaps were selected for landing and a nice high idle saw a nice decent profile and lovely nose high touchdown. Cool,,, two great flight for the day and still in one piece.

More later guys, cheers,

Brad
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