Topic: 1/3 Fokker D.VI...again...

Comments good or bad. You must be mad , how can anyone find anything bad to say about this model , stunning job and I want one. 

If you can get yourself a fine brush, with a steady hand it's possible to hand paint on the markings as they would have been hand painted originally if they look perfect they will look wrong  

Problem is.......the bloke with the slightly shakey hand painting the fullsize creates 'wobbles' the same size as Mudders will painting them at 1/3.......to be correct, the wobbles need scaling to 1/3 as well......which would make them pretty dam small, so I'd say all stenciling needs to be as good as you can possible get it.

Also.....I always thought stuff like this was painted through stencilled onto the full-size......it certainly was in WW2......correct me if I'm wrong, but in WW1, was this not the case?

Phil

looks like it was hand done phil......original from OW......a sign writer would have been very good with a fine paint brush

The weights table I would do as you have done Mudster, the serial numbers I would make a card template and transfer it that way onto the fuselage.

The whole project is superb mate, a superb piece of kit, you should be very justifiably chuffed to bits with it. 

Ian.

looks like it was hand done phil......original from OW......a sign writer would have been very good with a fine paint brush

Well ya learn something new every day....thanks Dave

Had the stitches out this morning  ::cc

The rest of the day was spent painting. I free handed over the weight table and used masking tape where I could on the rest.




Dummy ailerons next then Cockpit combing, I got some of those tiny mick reeves eyelets, so I'll give em a go after a little more thought on what it should actually look like (no piccys available for the D6  )

Mud

Had the stitches out this morning  ::cc

are you sure midairs.... i can clearly see the stitching on the fuselage...

Fantastic job Mudders, I know where to come if I ever need a steady hand, that looks the dogs bitz 

O I'm sure all right, I felt every one  

Ere, just a thought folks, I'm not 100% on the crosses on the fus side. I only have the pic of the fullsize (a few posts above) to go by. In the back of the datafile it says the border on the fullsize was 150mm. I have painted mine 50mm and that is the cross in the middle thats left, but it doesn't quite look right to me, unless theres some optical trickery about  .

Anyone got a piccy of another Geeerrrrrrman jobby with the same early style X's, a side view would help methinks......

Cheers
Mudlington

Fantastic job Mudders, I know where to come if I ever need a steady hand, that looks the dogs bitz 

Cheers buddy, but wait till you see it in the flesh, that'll tiddle in ya crisps 

Hmmmmmm I was looking more at the sign writing than the cross 

PS. I'd like to know what people really think so far, not so good comments as well (constructive of course )

I told you at the begining of this page, but you obviously wasn't listening So I'll say it louder

         That's bleedin' gorgeous Mudder's  

I really like the effect of the dope on that fabric, It looks so authentic! Shows best what I mean in your wing photo's at the top of the page.........Yep, I like it!

Walts.

Thanks Walts  , I feel that I will only get better at this toy plane lark if people point out my shortcomings. Shortcomings that I may not have noticed, but some may be a bit too polite to point out if ya see what I mean. If I make a balls up or something goes wrong I like to know what the cause is so I can try and avoid it next time. Live and learn and all that.
Still.... it's nice to get compliments too 

Chocks away 
Mud  

Been playing dummy aileron cables tonight  Each cable is actually one cable doubled over at the top with a spring on the end. Open the hatch and hook the spring on. Shut hatch, done. Takes a few seconds, I hope it'll be ok in flight 





Now I need to rustle up a list of things to do to get finished

Mud

I had a go at cockpit combing, I'm not 100% happy but....

As some may know, I had a little engine trouble before the big RCMF crash (of 2009 naturally ). I seized the engine which was diagnosed due to lack of cooling, even though it was outside on the test bench.
This afternoon I rebuilt the engine, new piston, piston ring and head. She started no problem, I ran it for about 30secs and thats all I'll do for now having been advised to run it in in the air.
So now I need to get it mounted and plumbed in. Thing is I need to maximise any cooling I can to try and avoid further problemos.

I will post some piccys and await further advise 

Mat

fantastic Mat....wow......looking the biz......thanks for reminding about the wheels.......1/3rd scale......one day!

cheers

dave

Cheers dave, first attempt for me, learning fast 

Here are some piccys of the engine install, Phil (off off fighteraces ) has suggested I make one large hole in the top right of the firewall where the head/exhaust goes, but I don't want to weaken it 

You thoughts would be appreaciated lads,










Mat

I ran it for about 30secs and thats all I'll do for now having been advised to run it in in the air.

Whilst I hate to disagree with others more knowledgeable  or experienced in such matters that idea worries me greatly Mat     I'd want to be absolutely certain (damn sure in fact!) the engine was running fine and reliably before committing to aviation with such a lovely aeroplane.   If you're committed to running it in the air please, please, put it in something that doesn't matter first and make sure it's 100%.

My own view would be that if you can't run it on the ground, with forced cooling if necessary, then it shouldn't be in the aeroplane at all.    Also, when the engine is cowled as it is, if it is that sensitive to cooling (can't believe it is myself) then you are definitely going to need to arrange baffles in the cowl to take the air from those squitty little holes and make sure it all passes over the fins otherwise it will overheat ................

Just my £0.02

Alan

I've never bench run any of my Zenoahs for more than 1 tank before flying them.........these engines don't cause problems as far as I'm concerned, so I'd have no concerns what so ever about flying it after minimal running....if it works on the ground, there is absolutely no reason why it won't work in the air.

The small opening in the cowl should supply ample incoming cooling air, though some baffles to help direct this over the fins will help. The 6 small holes behind the cylinder I feel could be opened up to one large hole to give free passage of hot air away from the back of the engine out into the forward fuz (it can exit through the cockpit opening). The mounting footprint of the 38 and gearbox is massive, as is the gluing area of the firewall to the main fuz structure......I'd assume the wirewall is 3/8" thick......a 2" sq hole will have negligible effect in it's strength

Phil

my dear mudders, the answer so so blindingly obvious i don't kbow why i didn't say so before..

given that..

... you want a reliable engine for the maiden...
... you shouldn't ground run the new engine
... there is some doubt over the integrity of the new engine

Why not run the new engine in, in the pup....

I've never bench run any of my Zenoahs for more than 1 tank before flying them.........these engines don't cause problems as far as I'm concerned, so I'd have no concerns what so ever about flying it after minimal running....if it works on the ground, there is absolutely no reason why it won't work in the air.

The small opening in the cowl should supply ample incoming cooling air, though some baffles to help direct this over the fins will help. The 6 small holes behind the cylinder I feel could be opened up to one large hole to give free passage of hot air away from the back of the engine out into the forward fuz (it can exit through the cockpit opening). The mounting footprint of the 38 and gearbox is massive, as is the gluing area of the firewall to the main fuz structure......I'd assume the wirewall is 3/8" thick......a 2" sq hole will have negligible effect in it's strength

Phil

Ok Phil, I will do that, but to clarify, the firewall is 6mm ply  Would that still be ok 

Cheers
Mat

my dear mudders, the answer so so blindingly obvious i don't kbow why i didn't say so before..

given that..

... you want a reliable engine for the maiden...
... you shouldn't ground run the new engine
... there is some doubt over the integrity of the new engine

Why not run the new engine in, in the pup....

The thought had crossed my mind Stu, but if I can avoid the hassle I will  . I had also thought of just using the pup engine and bolting the r/d to it, but I should'nt have to really, I got a brand new engine specially for the D6 

The thought had crossed my mind Stu, but if I can avoid the hassle I will  . I had also thought of just using the pup engine and bolting the r/d to it, but I should'nt have to really, I got a brand new engine specially for the D6 

how reliable has the pup engine been mudders....

Blimey, it took me so long to type my post that I had to log back in and then when I did there was another 6 or so posts!!

Anyway heres what I wanted to say, some of which has already been said......

I too would want to run it for longer than that on the ground mate but its your installation that wants the testing, not the motor and drive especially. The motor and drive will run perfectly in another model, but it still needs to run perfectly in this aeroplane. The firewall behind the exhaust, could you join a few holes up to make one much bigger hole behind the exhaust and cylinder head? This will drastically reduce the heat build up in the cowling. The engine position in the Fokker is nearly the same as in my Camel, though on the inner fuselage sides on the Camel (the vertical infill between the upper and lower longerons) I have fretted this out so the heat can also get out from the side cheek near the head, out through the cockpit. Zenoahs are very tollerant of being in hot situations with no issue.

In my DH2, the Zenoah had no propwash at all going over the engine, just what managed to creep through from the cockpit. That would, if allowed to tickover for too long on the ground, overheat but it always let you know by not throttling. It was never damaged by this abuse in the 4 years I was the abuser, so I am very suprised that the damage caused to your motor you have put down to overheating. Obviously I have only seen the pics you posted I think you are being hard on yourself. Run it longer on the ground mate, you know it makes sense. You don't have to thrash the bearings out of it, just satisfy yourself that it is reliable. Anything over 1/3 throttle and you'll be pylon racing anyway. I would run it on the ground enough to make sure it throttles smoothly, provides enough grunt and bits don't fall off, a couple of minutes should sort that then its fun all the way

Ian.

Absolutely Stu, I see your point, and agree, but the new engine 'should' be just as reliable. I have to make it work or buying it was a waste of time, and I need to learn how for future reference. I have no reason to believe this new one will not be as reliable, with the correct installation and running. While the new engine was running today, I did the very scientific test of holding ones hand behind the prop, feeling the airflow over the head, and there ain't much as the prop is sooooo big, it doesn't start scooping air effectively until it's outside the arc of the head, if ya see what I mean. BUT others run them in the pups etc ok, so why should this be any different??

Mudders

...... hey mudders, when's the maiden,,, are you open for spectators. 

Blimey, it took me so long to type my post that I had to log back in and then when I did there was another 6 or so posts!!

Anyway heres what I wanted to say, some of which has already been said......

I too would want to run it for longer than that on the ground mate but its your installation that wants the testing, not the motor and drive especially. The motor and drive will run perfectly in another model, but it still needs to run perfectly in this aeroplane. The firewall behind the exhaust, could you join a few holes up to make one much bigger hole behind the exhaust and cylinder head? This will drastically reduce the heat build up in the cowling. The engine position in the Fokker is nearly the same as in my Camel, though on the inner fuselage sides on the Camel (the vertical infill between the upper and lower longerons) I have fretted this out so the heat can also get out from the side cheek near the head, out through the cockpit. Zenoahs are very tollerant of being in hot situations with no issue.

In my DH2, the Zenoah had no propwash at all going over the engine, just what managed to creep through from the cockpit. That would, if allowed to tickover for too long on the ground, overheat but it always let you know by not throttling. It was never damaged by this abuse in the 4 years I was the abuser, so I am very surprised that the damage caused to your motor you have put down to overheating. Obviously I have only seen the pics you posted I think you are being hard on yourself. Run it longer on the ground mate, you know it makes sense. You don't have to thrash the bearings out of it, just satisfy yourself that it is reliable. Anything over 1/3 throttle and you'll be pylon racing anyway. I would run it on the ground enough to make sure it throttles smoothly, provides enough grunt and bits don't fall off, a couple of minutes should sort that then its fun all the way

Ian.

Thanks for taking the time to post Ian, The overheating issue came from Tony Clarke / Zenoah not me. I had already run the engine successfully for a total of at least 2hrs on the previous tank before the seizing issue.
That aside, I am happy to run it some more on the ground, I will naturally be more vigilant toward the possible over heating. I will cut one nice big hole around the head, do you think this would be enough?

Mat

...... hey mudders, when's the maiden,,, are you open for spectators. 

Only spectators that are willing to help with the brush and dustpan 

Only spectators that are willing to help with the brush and dustpan 

i would be honoured to be there and help in whatever capacity and am sure that the brush is not required, didn't you say it was brushless.....  can bring my 88" D7 for you to play with first if ewe like....

crikey, are we nearly there yet. remember our conversation at wings and wheels last year when you were hatching the plans... what happened to that 9 months eh.... now you have a model that will hold it's own with the rest...

total respect to you old chap. 

I've never bench run any of my Zenoahs for more than 1 tank before flying them.........these engines don't cause problems as far as I'm concerned, so I'd have no concerns what so ever about flying it after minimal running....if it works on the ground, there is absolutely no reason why it won't work in the air.

I agree with you there Phil, but one tank is ~30 minutes not the 30 seconds that Mat mentioned! 

Anyway Mat, make sure one of your helpers has a video camera on the day!  We all want to see it.

Alan

Another thing that I did on my 1/4 scale EV was at the bottom of the firewall. Since the firewall was moved back to get the Zenoah in, a 26 in my EV, the bottom hole between the cowl front and the firewall was bigger than scale. This means that any excess air going into the cowl could take the easy route out of the bottom. I filled the bottom panel in to the scale firewall position with lithoplate, then formed a curved lithoplate panel from this new front edge, curving backwards and upwards to the model firewall. This in effect forms a scoop which can take from below the cowl front panel and send it upwards to the Zenoah. This also makes it harder for excess air to take the easy way out and forces more out through the firewall holes. The problem with Fokker cowls is that unless the motor is inverted, it is too easy for air to go in the two holes and then turn downbank before it helps the hot bit.

Ian.

Ok Phil, I will do that, but to clarify, the firewall is 6mm ply  Would that still be ok 

Cheers
Mat

PLENTY...........the 36lb (engine + radial mount) in the Skyraider was only bolted to 1" ply.......1/4" is still plenty for a 38, especially one that ain't ganna be working very hard

I agree with you there Phil, but one tank is ~30 minutes not the 30 seconds that Mat mentioned! 

True......I should have said I'd never run one for 'prolonged' periods on the ground....a couple of mins per run max, do this for 1 tank max and you'll be good to go.

Excllent, thanks everyone, thats what I shall do!

Right, wheres me dremel......


Mud

I have run the engine in a little more today, so far so good  I think it runs a little better than before, the tickover is pretty good and stable at 400 - 450 rpm, and the top end is about 2600rpm.

I have made a start on the fuel guage faring, I was going to make a mould etc etc but ended up making it from litho.





And I cut a big old ole in the firewall, still to be touched up with a fuel proofer...
 
               

Mud    

Is there scope for more holes in this area? What wood is here, balsa or ply? Either way, any holes in this area would be a great help in removing the hot air from the hottest area

Ian.

I also made up the little identification plate for the cowl, included in the kit it consists of a laser cut steel plate and 2 dry rub downs, the main and a load of letters and numbers so you can personalise it to the model you are doing.

The top is out as thats where the bearer is for the struts, but I reckon I could form a slot about 15mm wide in the side.



Will do 

Mud

Radiusing the LE of the main hole will also help....................