RE: CMP 120 Zero ARF Build thread
 

Yeah I'm running a Pro Glow Products SCRR105 Glow driver.
I started with only using 1 glow plug on each cylinder, but since the driver can run up to 5 glow plugs I now have two glow plugs on each cylinder powered up at 1/3rd throttle & below.
I have a vid of my bench test on the engine with the glow driver etc running inverted & very rich ( factory settings Plus the stock exhausts ).
I have the Saito flexi pipes for the 200Ti fitted up in the Hurricane.
Just to help make up your mind.:)
I'm building a Zero at the moment as well ...love them, really wanted to get the Saito FG57T for it but money was a problem & ended up getting a cheap zenoah GT80 for it instead, should still sound ok I hope with the custom exhaust.
All the best Steff.


http://www.youtube.com/watch?v=N3IcX7skFVw

RE: CMP 120 Zero ARF Build thread
 

Hi Chaps, I haven't looked in for quite a while on account of damaging my own Zero after just a few flights trying to get it in over tall crop on our smallish field hot with no flaps! I put it up the corner and left it for a few months, but have recently dug it out for repair. The worst of the damage was to the fus where the wing had ripped out, but it wasn't too difficult to put right in the end. Once It was all repaired again, I thought I might as well add flaps to it to make the landings more enjoyable! I didn't fancy having to try and match up the paint work, especially after all the effort weathering and panel lining the original covering. So a bit of careful measuring and cutting meant I preserved the original covering panels ready to be re applied to the new flaps. I've tried to keep the flaps as scale as possible inside and out, this was the end results.

http://i40.photobucket.com/albums/e2...08/Zero039.jpg

http://i40.photobucket.com/albums/e2...08/Zero040.jpg

I also decided to re engine the model while I was at it with a Laser 150, didn't much like the RCV 120 sp. Just waiting for some last bits to turn up to finish the engine install, then it'll be ready for a new test flight;)

RE: CMP 120 Zero ARF Build thread
 

Best flaps on CMP Zero I've seen! ;)

What hinges did you use?

Good luck with the re-maiden

RE: CMP 120 Zero ARF Build thread
 

Thanks Vasek;) I checked out some full size pics and three view drawings and noticed that there is no visible hinge on the wing surface, so decision was easy! Simple mylar hinges bottom hinged.
Regards,
Walts.

RE: CMP 120 Zero ARF Build thread
 

Walts, would you share some of the techniques you used during the cutting of the flaps? are those ribs "original" just cut down & how did you drilled the holes in them? how did you make such a clean cut at the trailing edge? any info on the process is welcome. thanks

RE: CMP 120 Zero ARF Build thread
 

Certainly Vasek;)
First I found this picture on the internet to use as a guide for what I was trying to copy

http://i40.photobucket.com/albums/e2...flapdetail.jpg
Then looking at three view drawings I saw that the flaps were in line with the ailerons, so figured that would make them easy to cut out on the rear spar. For some reason the rear spar is 1/4 " further back than the aileron line! That was OK because It allowed me to glue a piece of 1/4" balsa under the wing skin against the rear spar giving a much more solid spar to hinge to. The sheeting was cut out cleanly and the original film peeled back. Once the new spar was glued in the film could be stuck down again up to the hing line and trimed off and saved for using again on the new flaps.

http://i40.photobucket.com/albums/e2...08/Zero023.jpg

The original ribs were cut out (obviously before the new spar could be fitted) and the trailling edge completely removed leaving just the top skin in situ.
http://i40.photobucket.com/albums/e2...08/Zero024.jpg

The flap bay was then lined with 1/32" birch ply attached with contact adhesive.
New ribs were cut and scalaped to allow for the flaps to lay in them. They were 'drilled' to represent the full size flaps using a sharpened piece of tube twisted in to them by hand.
http://i40.photobucket.com/albums/e2...08/Zero026.jpg

The flaps themselves were made from 1/32" ply bases with 1/4" balsa leading edge and balsa ribs. the scale spar goes a long way toward stopping them warping.

http://i40.photobucket.com/albums/e2...08/Zero030.jpg

Everything was sealed with sanding sealer, rubbed down, primed, wet & dried back and painted. Then hinged with mylar hinges. The horns were made from ply and servos mounted on ply plates epoxied to the top wing skins, and all linkages kept internal.

http://i40.photobucket.com/albums/e2..._1/Zero033.jpg

http://i40.photobucket.com/albums/e2..._1/Zero035.jpg

http://i40.photobucket.com/albums/e2...08/Zero029.jpg

The original covering was ironed back on to these flaps to preserve the original finish.

http://i40.photobucket.com/albums/e2...08/Zero027.jpg

HTH's Vasek, If you need any more info just shout mate ;)

RE: CMP 120 Zero ARF Build thread
 

Nice work !!, looks awesome !.;)

RE: CMP 120 Zero ARF Build thread
 

I'll second that!! Those flaps are spot on there, Walts

RE: CMP 120 Zero ARF Build thread
 

YES incredible job Walts! the pictures are spot on, just 2 more questions:

-did you split in half the existing trailing edge with an exacto?

-to remove the covering, did you heat it up a bit?

I'll be copying your process as close as my ability will let me ;)

Thanks,
Vasek

RE: CMP 120 Zero ARF Build thread
 

Thank you for your kind comments chaps;)
Vasek No, the T.E was carefully cut through to the top sheeting then remove a bit at a time with a sharp scalpel and finally sand paper to just leave the top sheeting. Then even once the 1/32" ply was glued in place the edge of that was feathered down as can be seen in one of those pic's. The idea is to end up with the thinnest T.E. practical with the flaps closed. If you do your flaps the same as this, I would advise you use a smaller tube to cut the holes in the ribs so as to leave more 'meat' on the rib. My holes are much too big and leave weak ribs, but it was the only size tube I had laying around when I done the job, and the flap bay area feels strong enough for the job it has to do, even the full size wasn't very strong in this area, that's why they put no walk lines on top of the flap bay:D

The covering was simply cut with a brand new scalpel blade and a steel rule used obviously to keep the cuts straight, then peeled back cold. Be careful because it will tear as easy as anything as you can see in my pic it has started to go in places, this does iron back down though;) I painted all the areas where I needed to re attach the covering with Balsa loc. I don't know if you have this exact product available where you are, but It's basically a white glue that once dry you iron the covering on to it and the heat reactivates the glue and grabs the covering,...the covering Itself doesn't seem to have enough glue on it to stay ironed down again on It's own, especially over ply wood!

One more tip is when you cut the flap bay in line with the aileron hinge line this will leave the sheeting over hanging the rear spar by 1/4" as mentioned earlier. Once you have removed the old ribs and T.E. and before you add the new spar, add the 1/32" birch ply. This way you get the ply right over the top of the new spar for much greater strength to the flap bay. Oh,...and don't worry about trying to find a rib to cut the flap bay up to, just cut it to the best position you can and add a new end rib under the sheeting. On the full size the flaps start from just under the wing fairing, and go right up to the aileron. On this model you cant quite do that, otherwise you will have an angle on the flap where the T.E. becomes straight and it wont look right when the flaps are down, so I made mine just 1/4" shorter or so to keep the T.E. of the flap nice and straight. But do scallop the very last rib next to the aileron so the flap can be fitted full length right up to the aileron.

Regards,
Walts.

RE: CMP 120 Zero ARF Build thread
 

will do THANKS!

RE: CMP 120 Zero ARF Build thread
 

I am glad I haven't started on my zero yet. I like the scale flap mod you did Walts.
Your pictures are worth more than a thousand words. When I start mine I am going to use your tutorial to install flaps along with the retract gear attachment mod mentioned earlier in this thread.
Might as well do it all at once . :D

RE: CMP 120 Zero ARF Build thread
 

WD, can you point me to the retract gear attachment mod page? thanks

RE: CMP 120 Zero ARF Build thread
 

Beautiful job Walts. Can't wait to see this Zero in the air.

RE: CMP 120 Zero ARF Build thread
 

Thanks again chaps;) Guy's when you do the retract mod, do it once and do it properly! Not like me! I done a bit of a bodge on mine to try and not cut up the wing too much. Mine is still not very strong and I will need to be very careful with it at all times! Misha shows a very good mod for the retracts on page 12 post #300. Thats what you really need to do! Cut the whole lot out and add new ribs from substantial ply, and spread the load on the retracts over several ribs, not just two like they have designed it, the model is far too large and heavy for that! and the long legs offer a lot of leverage too on the mounting if you hit the ground at the wrong angle! I can see I will eventually be doing mine properly too :eek:

RE: CMP 120 Zero ARF Build thread
 

L16pilot did a clean mod back on page 16, p.ost 386

RE: CMP 120 Zero ARF Build thread
 

Attached are a few photos my Zero has a DLE 30 and beed flown a few times not sure why the gear folded as I beefed up the gear mounting area as talked about in this thread.. When I rebuild I will use fiberglss cloth to reinforce all the gear area..[img][/img]

RE: CMP 120 Zero ARF Build thread
 

Rainbow1,

I modified my gear mounts first thing. With my flying on our grass field I needed a lot stronger mounts. Posted about it earlier but pictures won't come up there. I opened up the entire gear area wing bottom and built new gear mounts. They have been well tested and have held up so far.

RE: CMP 120 Zero ARF Build thread
 

Here it is more or less finished. I moved the gear mount in one rib bay and made struts sligthly shorter and used larger wheels, 4". May not be quit scale but it holds up.

RE: CMP 120 Zero ARF Build thread
 

Nice work RBean. :D

RE: CMP 120 Zero ARF Build thread
 

I picked up on of these hard to find kit recently,, I plane to use the DLE 30 also,, but will convert it into a Rufe float plane ;)

RE: CMP 120 Zero ARF Build thread
 

I will definitely be looking forward to seeing your build documented here! That just sounds WAY cool:D

RE: CMP 120 Zero ARF Build thread
 

Whish you all Marry Christmas and Happy New Year,

RE: CMP 120 Zero ARF Build thread
 

To you as well!!

RE: CMP 120 Zero ARF Build thread
 

To all my CMP120 Zero basher brethren, I hope you all have a happy and safe New Year. I haven't updated on this thread since the initial flight of my Zero earlier this year, so here's a quick recap. I finished the Zero as an A6M3-32 "Hamp", weighs 18 lbs with Robart retracts and a DLE-20. I added flaps, reinforced the grear mounts and added 25% to the elevator surface. I balanced it at 135mm. First flight was great until landing....my test pilot got it a bit slow with a cross wind and it hit hard on the left gear leg to the point that it bent the Robostrut and deformed the aluminum trunnion...but did not damage the gear mounts in the wing, so the reinforcement bashing must be pretty good. Also cracked the firewall around the plywood reinforcement. Tooks several weeks to get new Robart parts and everything repaired. Have since flown the airplane and I must say it flies fantastic. The DLE-20 has plenty of power and I cannot imagine this airframe with a DLE-30! All is on charge tonight and the weather is supposed to be super for a New Years' day flight...or three.

Cheers!