My Fokker DVII Project - Page 50

Maxim08 · 11 March 2007, 04:43 PM

Troy & Jeff,

GWP is correct in that the external dimensions of the a/c are correct including the distance from cabanes to the nose.
The engine is as far forward as practical/possible within these confines.
The secret is in the lower right corner of this image.

There is probably enough lead shown to arm a staffel of DVIIs.
Regards,
John

RFC Pilot · 11 March 2007, 05:26 PM

Hey Jeff....

She looks to be coming along nice.

As Ed said, there are still issues with the W/B. With the SE5a, we are moving the engine forward 2 inches, to get rid of close to 80 pounds of lead that was attached to the front of the engine mounts.

Given the way the DVII flies, there are probably some issues there as well.

Jeff Brooks · 11 March 2007, 07:02 PM

yeah, right now I'm not sure what I'm gonna do. Leaving the engine far forward like that helps the CG and the magnetos have plenty of room if the engine vibrates. But the engine sticks out a good 5-6 inches from the measurements on the replicraft drawings. I figure the radiator should be about 1300mm from the rear cambane strut to the front of the radiator.

look at these 3 photos and do the math ... the radiator is 270mm plus the 1000mm from the rear cambane strut, plus the 30mm gap

Von Writter · 11 March 2007, 11:02 PM

Nice work Jeff, my DVII has been slowed a bit as I bought a Cessna 140 to fly while I'm building and am painting it. How much will your Ranger installation weigh when you are done? My RWS Wright engine installation is 530 lbs. wet with radiator and ignition.
Best regards;
Troy W.

Jeff Brooks · 12 March 2007, 02:22 PM

Well, the engine with the magnetos weighs in at 420lbs, but even with the oil cooler and various plumbing, it will not get me close to the 900lb ( + / - a couple of 100lbs) BMW I need.
The placement of the engine makes a big difference! Like the GWFM did, by placing the engine as far forward as possible (while keping the outside dimentions the same), they get the most out of the weight they already have. I am having trouble moving my engine forward and staying withing the original dimentions because of the magnetos. Maybe thier builder was smart enough to have made the changes to the frame to fit the ranger.
Frankzait said this exact thing to someone else on another post, and he is right. I didn't have the engine before starting construction. The importance of this is crutial. If I had, I would have made a number of changes:
1. The engine bearers 1/4" closer together to make the original engine clamps fit correctly.
2. I would have moved the trusswork under the engine bearers to fit the engine with the magnetos in the correct place.
3. I would have lowered the engine bearers to align the engine crankshaft with the thrust line.
It would almost be worth sending the changes to Jim Keger as a Ranger mod for DVII builders!

tengew · 13 March 2007, 06:41 AM

Jeff
Why don’t you draw up every thing you have found?
All those just not right. And offer them your self as a set of re-work plans
Help with the cost off sets.

tengew · 13 March 2007, 06:44 AM

other than a compleat pain in the bottom how long would it take you to make the needed changes to your plane so your ranger will fit just right?
do you have the steel on hand or is it needed???

you might just need to do it .

dtenney · 16 March 2007, 11:12 AM

Jeff,

Some very nice work you have done sir! Very nice indeed! I am impressed at your dedication, I hope my project comes along as nicely as yours! And, you've done it on a military budget - which makes it more impressive. WOW.

Anyhow - looks like you're going with a ranger? Thats a good choice, anyhow - great photos. I will keep an eye on this thread to keep up with your progress. Thanks..

dtenney

Jeff Brooks · 16 March 2007, 01:55 PM

dtenney,
Thanks. Have you started anything on your DVII yet? If you need help on anything, drop me a line ... I still have many of the jigs to make stuff! Go with the Replicraft plans. Unless Achim has finished his. He is drawing his plans as he makes his planes, so that guarantees everything on his drawings will line up! I suggest you pick one set of drawings and stick with it! I am working with many different drawings, and things sometimes don't line up like they are supposed to!

Today, I moved the engine back to where it was and made the final adjustments. I set it to 300mm ahead of the front cambane strut on the engine bearer.

The cowls line up with the false radiator. That makes me happy!

I put the correct AN bolts on the bushings, but I am waiting for the correct size for the clamps.

I had to make my own 2 1/4" washers out of 1/8" steel. apparently they don't normally stock 2 1/4" washers for 3/8" holes at the local hardware store!

Jeff Brooks · 16 March 2007, 02:10 PM

I have about a 1/2" worth of clearance on the left side ...

And a 1/2" on the right ...

One of the things I like about this position of the engine is, that the clamps and the bracket are between the cambane strut & trusswork. This means that if the clamp slips, there is no place to go!