Topic: 1/4 scale Fokker DVIII quick (?) refurb.

I got me a 1/4 scale BUSA Fokker DVIII last weekend.

This has been on my wish list for a long time, so when one came up in the classifieds I was immediatly interested.

This is what she looks like all asembled.

Anyway to work.

The engine firewall has to go as it resembled a piece of Swiss cheese.

Happy to report that the firewall came out smoothly and was pleased to see that it had been pegged in.

Now to clean the area back to good wood. Not that it is not. The fuel proofing seems to have been well done as there is no sign of fuel soaked wood.

Nice wood mate 

Looking forward to see this fly - its been sat around too long.

Chris

As it stands I have two engine choices at the moment,

A home conversion of 28cc or a CRRC 40cc.

Sovereign 28cc Conversion.



CRRC 40cc


Side by side.



The conversion has a longer than desired prop adaptor but Norfolk"n"good has offered to reduce the length of that for me.



The CRRC fits as if made to measure.


Which one then? Would the conversion be man enough to pull it around and likewise would the CRRC be to much?

Ooooo, nice, what engine will you go for?

Ooops, we posted at the same time!

I flew a 1/4 scale Dr1 Triplane on a champion 28cc conversion and that was a good match. What are the weights of each like, will one suit the c of g more than the other?

The BUSA website has the CofG at 4" back from leading edge of wing at Center Section.

Not able to weigh the engines at the moment,but the conversion feels the heavier of the two.

I have no plans or any other info, so if anyone has built one or has any plans etc, I would apprecite it.

I would be tempted to go with the 28. You'll need nose weight probably (  ) and the characteristics of that engine would be more suited to the flying razor.... Then the CRRC40 could go in a nice WW2 fighter.... 

I would be tempted to go with the 28. You'll need nose weight probably (  ) and the characteristics of that engine would be more suited to the flying razor.... Then the CRRC40 could go in a nice WW2 fighter.... 

The 28 would be my prefered choice also.

The 28 would be my prefered choice also.

So let's both put on flack jackets and wait for the "incoming" 

PS, Peter Wilkins flew his 1/4 scale DV111 on a Zenoah 26 and that was ample.

New firewall cut and placed in for fitting later.

Subscribed.  My first ever rc airframe was a veron D8 

Removed and tested all Servo`s, all working well.

Standard Futaba FP-S148`s all round. 

Thinking that I might replace them with some 6kg or so of torque, servo`s. 

just caught up with this, I would think your conversion will be sufficient if it will rev up on and hand start.  Before making a choice I would mount it up on something and see what revs you can get with what prop I would guess a 19 X 8 prop would be a good starting point.  Either put the firewall back a bit or I can probably machine a bit of the rear of the driver maybe a bit off the flywheel if necessary but would think we would be into the taper quickly so maybe not.
Servos, I have TP5010's and after using the much slower to operate Hitec's I would go with something slower to aid smooth flying.  Like I said at Winterton I flew my 1st 1/4 scale SE5a on Futaba 148's  and had no blowing back of surfaces inc the single 148 on the elevators my only issue with them is slop.

1st job get that engine running with a prop and see what revs you can get 

Looking like a nice refurb well done.

1st job get that engine running with a prop and see what revs you can get 

Well thanks to Shaun "Norfolk'n'Good" the engine has been run up and fitted today. Using a prop adaptor that I already had, Shaun turned down the flywheel and front face to better accommodate it.

Mounted on a test stand we got 5600rpm before any adjustments ere made.

Shaun got a short video clip which I hope he will upload to youtube, and add a link to this thread.

Tomorrow I will get some pictures of the installation.

I have to so that both of us were supprised at how quite the engine was. Along with that there was very little vibration and the transition from idle to full bore is smooth and easy.

I am hopping to have it ready for Tibenham on Friday evening, but fear it may just be static.

Kev

Well thanks to Shaun "Norfolk'n'Good" the engine has been run up and fitted today. Using a prop adaptor that I already had, Shaun turned down the flywheel and front face to better accommodate it.

Mounted on a test stand we got 5600rpm before any adjustments are made.

Shaun got a short video clip which I hope he will upload to youtube, and add a link to this thread.

Tomorrow I will get some pictures of the installation.

I have to say that both of us were supprised at how quite the engine was. Along with that there was very little vibration and the transition from idle to full bore is smooth and easy.

I am hopping to have it ready for Tibenham on Friday evening, but fear it may just be static.

Kev

I have to say I'm impressed with that little engine and am looking forwar4d to seeing it pull the DVIII round.  I'm sure the revs will go up with a different prop an 18 X 10 is a deep pitch.

<a href="http://www.youtube.com/watch?v=8pl7pytGhZs" target="_blank">http://www.youtube.com/watch?v=8pl7pytGhZs</a>

Hello,
I am new to petrol/gas engines.  My DLE55 is brand new.  Would you guys say it is o.k. to break in on bench or break it in on the plane by running say 3 to five full tanks...ea. tank running for 20 minutes?  I day time temperature an issue?  It gets to 115 degrees F. here in Arizona, USA.
thanks,
Albert

Would you guys say it is o.k. to break in on bench or break it in on the plane by running say 3 to five full tanks
Albert

Personally I run 1 tank through on the ground with a high oil content 40-1 fully synthetic using all throttle settings but not holding it on full throttle for more than a few seconds at a time then put the engine in the plane and go fly but again without using full throttle for any long periods.  After the 1st gallon of 40-1 I go to 50-1 fully synthetic.

I'm not saying this is the correct procedure but it's the way I do it.

As promised.

The rain eventually stoped and I was able to get to the shed.

<a href="http://www.youtube.com/watch?v=7hE5PTTIYRQ" target="_blank">http://www.youtube.com/watch?v=7hE5PTTIYRQ</a>

Still lots to do.

Looks good mate    just need to polish that slap a bit more of a rotational slap than just slapping straight if you see what I mean    Also need a support on that snake outer but looks like it's starting and running very well.

Looks good mate    just need to polish that slap a bit more of a rotational slap than just slapping straight if you see what I mean    Also need a support on that snake outer but looks like it's starting and running very well.

Yep, snake support is the next on the list along with some form of cut mechanism. Also need to slow the tickover down a bit. Fine on grass but on concrete there is a lot of creep. Also required a slightly smaller pitch prop. Still running the engine on 40:1. That will be reduced to 50:1 with the next 5 litres of fuel.

The "slap" is getting easier!! That was with a warm engine perhaps 10 mins since last run. The couple of start prior to that were a lot better.

Shame it wont be ready for Tibenham.

Did you manage to get any more done?  is it ready?  can we finish off any little bits at the field? and.............. have you managed to start the engine by hand with the cowl on 

Looking good mate 

Chris

Engine installation complete.

At idle the tacometer reads 2500rpm. I can get that down with a little adjustment.

At full throttle the tacometer reads 6000rpm. An improvement over the 5600rpm with the 18x10 prop.

So now it is all together I need to remove the prop and cowl so that I can remove the exhaust!!

So the exhaust is off.




As it stands the gases escape from the small hole botton centre. This is not good as it exits straight against the fibreglass cowl.

My proposal is to blank this off and make a hole in the bottom and add a length of copper pipe to form an exhaust outlet.
Are there any issues with this? Should I increase the size of the outlet hole?

Any advise greatfully sought.

It looks similar to what I do to Zenoah 38 exhausts which works well so It should be fine

Alan

It looks similar to what I do to Zenoah 38 exhausts which works well so It should be fine

And me .....

This the Z38 exhaust for my P51

Drill two holes, cut 2 off steel exhaust tubes, flatten the louvred exhaust outlet, silver solder it all up and put a 90 degree bend in the exhaust baffle



I always have a chuckle to myself when I see advertising material stating that "the Z38 is designed especially for model use"  shame they forgot to design the exhaust "especially for model use"

Alan

Thanks guys.

Exhaust exit now repositioned. Single outlet, and double the size of the original, getting an additional 400rpm. I really need to improve my solder/brazing skills.

So phase one (fuselage) completed.

I really need to improve my solder/brazing skills.

Practice makes perfect Kev ............

Today, I have mostly been restoring a bird bath by making a brass collar that's silver soldered together.  What I should have done is build a temporary brick hearth to keep the heat in.  What I did do was struggle because the collar was a fairly big chunk and it was a bit marginal.

Rule number one = Make sure you can get enough heat in to the work
Rule number two  = Make sure the material is mechanically clean and use sufficient flux to keep it that way

Alan

So onto phase two. The wing.

In a previous life it would appear that the plane has had a 3 point landing. One of those points being one wingtip.

Where the wing is mounted to the cabanes, there is a 4 1/2 inch crease in the top wing surface.


So peeling back the covering revealed the crease. It occurs just to one side of a wing join with 2 existing ply braces.


I have made 3 ply braces tapering towards the outer edge lessening the sudden stop of the brace, thereby adding a smoother transition from brace to no brace. (Thanks Shaun )


As you can see from the above and below shot`s the wing is made from a kind of pink foam!


Question. Some epoxys eat foam do they not? How the heck do I know what sort of foam this is and what sort of epoxy should I use? There is not enough of the foam removed (cut it out in the garden rather than the workshop, to save on mess) to be able to do a test on.

Use Gorilla Glue also known as PU glue

Tons better than Epoxy as it creeps into the structure...

Use Gorilla Glue also known as PU glue

Or Wudcare, same but cheaper(?)

I hate to think what I will find when I lift the covering on the DVII That's done lots of 3 pointers 

Alan

 That's done lots of 3 pointers 

Alan
[/quote]

Not when i had it though... 

I hate to think what I will find when I lift the covering on the DVII That's done lots of 3 pointers 

Alan

Always reminds me of this one..........



Osbournby 26-09-2010   (6) by Kevin Fairgrieve, on Flickr


Two wing tips and a rudder..

Not when i had it though... 

No, but you've a nice line in comedy Pup take-offs IIRC 

No, but you've a nice line in comedy Pup take-offs IIRC 

That was for the sake of art.... 

Always reminds me of this one..........

Ah, I remember that well.

After a long treacherous dog fight, "Betty" got the upper hand and riddled the DVII with the fruits of its Vickers ....

3 new wing braces Gorilla glued in place.



Glue trimmed off. All minor blemishes filled with model light filler, and then a thin coat of finishing resin over the top.



All that's needed to complete is a final rub down with some wet and dry, then recover with some Solartex.

Should be completed tomorrow.