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        Build Log VIDEO ADDED: Pro Design F-18 Build

#1 MattinAZ Dec 06, 2009 05:22 PM

VIDEO ADDED: Pro Design F-18 Build
 
2 Attachment(s)
I will be buidling this plane this week and posting as I go. Will include detailed pictures as work progresses.

First impressions of the F-18 pro design ARF are very good. Fiberglass work is nice and relatively light. Hardware supplied is of good quality and design.

The design of the plane is excellent which you will see as I post more pictures. Intake ducting is already there. Exhaust ducting come with it too. It is bi-furbicated and I am not sure if this will produce less thrust than a single exhaust but I plan on building it stock, take readings, fly it and then psoobily modify it for a single exhaust. If it flys well I might just leave it be. We will see.

All the formers are installed with exception of the taileron bulkheads which need to be assembled and installed. The formers are all well glued into the plane and are well designed. The plane comes setup for retracts but includes some additional wood pieces that can be screwed in so you can used the supplied fixed landing gear and still easily add the retracts later - Purely Brilliant!

Ok, enough of the nice talk lets build this bird.

First thing to assemble is the taileron bulkheads. You get all the pcs reuired to build them. First thing I did was to add some 100% silicone grease to the bearing sides to keep CA out of them when I install them in the black block. Used a small amount of thin CA with toothpick on the bearing block. This will keep you from loosing the tiny bearings as you do your assembly. I am now waiting on the epoxy to dry to finish the talerion bulkhead.

#2 BulletMaster Dec 06, 2009 05:50 PM

watching... (I hit the buy button myself today :) )

#3 MattinAZ Dec 06, 2009 05:50 PM

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While I am waiting for the epoxy to dry started to take a look at the wings.

They are short because a large portion of the wings are molded into the fuse. I plan on using HS81 servos as shown in the picture below. Instructions call for smaller 9gram servo but I am not comfortable with that since my setup will use the ailerons as flaps in addition to ailerons. So HS 81 it is.

Instruction say to glue to inside of pocket but i think I will add some blocks and screw them in. This is a 90mm size jet and desrves a little better.

#4 mpope1 Dec 06, 2009 06:25 PM

Matt, cant wait to see this one in the air. I heard they are coming out with a 90mm f-86. I am patiently waiting...

#5 MattinAZ Dec 06, 2009 06:49 PM

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Decided to go with some small bass wood block which will accept a piece of ply screwd down to lock the servo in place. Will then use some grey monokote squares to cover.

Added the last wood piece to the taileron bulkheads and waiting for epoxy to dry. Using 30 minute epoxy on everything.

Will start preping wings butt joint to fuse surfaces for epoxy tonight.

Matt

#6 MattinAZ Dec 06, 2009 08:58 PM

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Well this is not going to be much of build thread and you guys arent going to get to participate much. Why? I am about 30% complete with the plane.

The tailerons bulkheads are complete. Make sure you build mirror images of the taileron bulkheads. I will let the bulkheads dry over night before I start putting them in the fuse. The taileron servo cutout is just the right size for a 9gram servo but too small for the HS 85BB's I am going to use. You can just see the outline where I have to open them up a bit.

You have to drill a large hole thru the fuse to line up with the servo thru hole in the wing. I sanded all the paint off the fuse wing joint. Sanded the wing rib that attaches to the fuse.

Wings were just epoxed on (not shown). So I am going to let everything sit until tomorrow.

#7 MattinAZ Dec 06, 2009 09:02 PM

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Here are misc pics for you huys to look at.

#8 BulletMaster Dec 06, 2009 09:29 PM

coming along well Matt....

How long did it take from ordering to delivery for you? Also, which country is ProEDF based in?

#9 MattinAZ Dec 06, 2009 09:59 PM

About 1 week. I will look at the shipping box tomorrow to see what country it came from.

Matt

Quote:

Originally Posted by BulletMaster (Post 13758545)
coming along well Matt....

How long did it take from ordering to delivery for you? Also, which country is ProEDF based in?


#10 Ed Waldrep Dec 07, 2009 10:52 AM

Thanks for the pics Matt.

A question: just how narrow does that inlet ducting get a few inches back? And what does it do afterward? It looks pretty narrow. I guess they did that to clear the wheels but from the pics posted it looks like it gets narrow then as it goes backward it expands again to the face of the fan, with no center tube to match up with the spinner to help maintin the cross sectional area. That'll be some drag but not a show stopper, it's better than no ducting at all.
Have fun!

#11 MattinAZ Dec 07, 2009 12:10 PM

Ed,

Hope the below is what you are looking for-

Each inlet is 2.75 in x 2.5in which gives a total area of 13.75 which is more than 100% FSA of Midi fan. So yes, there is will be some unnecessary drag caused by too large of intakes but I dont think it will be much. FSA for the Midi is about 8.2 sq inches if I calculated that right. Correct me if I am wrong.

Its hard to get a good picture of the inside of the ducting. I know what you are asking, but it is impossible for me to easily take the measurements to see if it has good "area rule" at different cross sections down the ducting. If I was to guess they did a pretty good job of creating a smooth "funnel" down to the fan. Could it be better? Probably but at what additional cost. I am not saying this to defend the designer just that I know in every design there are tradeoffs between, Perfection, Time, Effort and Price. I think they did a great job with the balance.

And Ed, I would expect yours to be better knowing you and your planes : ) My problem is I am a hack and ARF's are all I do.

Matt

#12 therealhiphop Dec 07, 2009 04:48 PM

Subscribing

Hey Matt - a bit off-topic, but is that the HET A-10 I see in the background? Just looks bigger than I thought...

Thanks for the build thread on the ProEDF 18!

#13 MattinAZ Dec 07, 2009 06:10 PM

No, it is the old EJF A-10. Wish they still made this bird as it an excellent flying and looking EDF. WS is about 50" twin 70mm 2W20 and it moves out well for such a draggy airframe.

Quote:

Originally Posted by therealhiphop (Post 13764371)
Subscribing

Hey Matt - a bit off-topic, but is that the HET A-10 I see in the background? Just looks bigger than I thought...

Thanks for the build thread on the ProEDF 18!


#14 zach_dad Dec 07, 2009 06:22 PM

Plane looks awesome, I guess you bough it at X-flight? I bought the HET single 90, this plane is about same weight when finished 3400 grams or 6.5 to 6.8 LBs. Im having trouble getting my bird to be FAST. I'm running a Jetscreamer 90mm and the HET fan. I tried on 6s but had to keep the trottle in it all the time very poor performance. The Watt metet read 56Amps 1200 watts of power. I jumped to the 8s setup and got 81 amps and 2400 watts. a little better performance but still if I hold the plane up with hand and put full throttle the plane will not hover and falls back, I'm used to the plane having better than 1 to 1 ratio but it looks like Im gonna have to go to a 10s system, a better fan, and better motor. I was thinking the 90mm Lander fan, and nue motor. Maybe I can keep cost to about 220.00.

#15 zach_dad Dec 07, 2009 06:25 PM

Oh one more thing it might be my pipe size would u mind telling me the opening and exhaust size ot the inlet and double exh. I think the HET pipe narrows to quickly.


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