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-   -   Skygate Hawk - build (virtual manual) (https://www.rcuniverse.com/forum/rc-jets-120/9222791-skygate-hawk-build-virtual-manual.html)

marc s 04-08-2010 03:16 AM

RE: Skygate Hawk - build (virtual manual)
 
They look like they are going to get bashed at any opportunity.....
Shut off valve has been done like this to get it as close as possible to reduce fuel line length, only done smoke one currently and the line length is no longer than it would have been without, the valve is placed 1 inch away from the pump. The fuel valve shut off will achieve the same. If I had placed the valves so that they were accessible to fingers the fuel lines would need to have been considerably longer.

marcs

Ali 04-08-2010 04:32 AM

RE: Skygate Hawk - build (virtual manual)
 
Thanks for that. I can have a marking made and applied to the airframe to show which way on-off is on those valves.
Good to hear tubing lengths are short.
Dont worry about removable fins. Its just more weight at the back end where we dont need it. A decent cradle protects the fins in transit.

simont 04-08-2010 06:45 PM

RE: Skygate Hawk - build (virtual manual)
 
Oops, sense of humor bypass. :D:D

marc s 04-09-2010 01:27 AM

RE: Skygate Hawk - build (virtual manual)
 
Now now!

marc s 04-12-2010 04:27 AM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
Finishing off the small detailing on the rear fuselage section, I had to cut the two large rectangular vents out, which in itself is tricky to get nice straight lines - then the fun started, getting the supplied moulded intakes fitted, hours or filing, sanding and fettling. Eventually go the fit about right and will look OK once a slither of filler is added to the glue joint areas and painted. One little piece of advice, the moulds are square (ish!) the fuselage is not, to get the end of the moulding to follow the contour of the fuselage I heated it up with a blow gun and when warm enough to be pliable I set it over the side of a coffee cup to give it a slight curve, this mated nicely with the fuselage, and reduces the finished required to get a nice edge.

On the leading edge of the two vents are little deflectors, I was sure they were in the kit as mouldings - could I find them [:@] spoke to a friend who has built one and he said they were very basic and required alot of altering to get them to fit so I had to make my own....

Traced the opening shape, cyano'd 4 small pieces of balsa together to make a block, made a template from a thin piece of scrap FR4 and cut the block to shape, using a FS picture as a guide to the shape. Once sanded applied an even layer of thin cyano, sanded smooth, added another layer and sanded, once fairly smooth I cyano'd the whole thing to another piece of scrap FR4 to make the base - the whole thing took 10mins to make - a record for me! Made a test 'deflector' last night using 2 layers of light cloth, result is a good fit and not bad on the scale looking front as well. Will make two in white pigmented glass tonight, maybe adding a third layer....

Made a small fuselage vent and started on the main plumbing and wiring, fitted the smoke pump into the former cut-out and made up extension leads for the two elevator servos.

Made and fitted a battery mounting for the two 2s lipo packs, this now finishes the battery allocation, 5 items in total. Added a pic of the three air tanks hooked up (as Ilike it!)

marcs

schroedm 04-12-2010 04:33 AM

RE: Skygate Hawk - build (virtual manual)
 
Marc, getting there now!!

Are you sure it's not going to be nose heavy with all those packs up front? I've seen several installs on several different models and never seen all the packs up front like that? Most sit alongside the wheel wells or by the fuselage join. My Hawk had the ECU pack in the tail, the light battery in the tail and the drogue chute in the tail with the lipos on the wing tube. This resulted in the CofG being as per the instructions - this isn't to say that's where it HAS to be as I know a certain someone who bought it off me felt it was awfully tail heavy and ripped me for it (and still does ;)) however, I believe he only then removed the lipos and put 2 nimhs just under the rear cockpit.

I know I'm going to get stick for saying that from a certain someone([8D]) but I'm fairly sure you will be waaaay nose heavy.

Rgds,
Mark

gregairbus 04-12-2010 05:05 AM

RE: Skygate Hawk - build (virtual manual)
 
I have to agree with Mark,
The Hawks I have seen have no packs in the nose and
have to add weight in the tail for best CG ?

marc s 04-12-2010 05:38 AM

RE: Skygate Hawk - build (virtual manual)
 
Not having experience I suspect you may well be right, the two packs under the nose gear frame are only held in place with foam and slide in so these two can be relocated if required without any problems, remember there is some extra weight around the bypass and new fuel tank area although the tanks are almost bang on C of G - moving packs is always part of the deal is it not ;)

marcs

Ali 04-12-2010 06:04 AM

RE: Skygate Hawk - build (virtual manual)
 
Having flown a few of these hawks I found the stock set up to be too tail heavy!
Great for those that wanted a f3a style plane that needed no down when inverted, but I just felt it lacked the solid locked on feel that a scale jet should have.
To confirm this. The last skygate hawk I owned from Schroedem actually had a battery and some lead in the rear chute area. I questioned this when I saw the model fly and it was obviously tail heavy and was told " Thats how he was told to balance so thats how he did it"
Well a few months later when I owned the model I thought to myself I would give it a try as he balanced it and knew right away that it was tail heavy as sin. I subsequently removed the lead. from the back end. Removed the battery from the back end and then added 2 6 volt 3300 mah sub C batteries to the front cockpit section ( Replacing the light 2 cell lipos located nearer the c of g. The result was.. A totally different aeroplane. Tracked better, sat better, had a much nicer feel on the elevator. Those that saw it commented right away how much better it performed after the changes, and I as a pilot knew right away it was a million times better. But hey! What do I know?
Marc. if Greg would like them moved back then so be it.
Regards Al

schroedm 04-12-2010 06:31 AM

RE: Skygate Hawk - build (virtual manual)
 
Al,

I'm not sure it was quite as bad as you're making it sound [8D] And the only battery in the rear was the 4cell nicad for the lights. No lead that I put in there [X(]


Marc,

pics from Al's workshop to help you plan for possible new locations...

http://i908.photobucket.com/albums/a...y/DSC_0011.jpg

http://i908.photobucket.com/albums/a...DSC_0018-1.jpg

The Jetcat ECU battery was mounted alongside the turbine too.

I accept Al's comments that it probably flew better, my warning to you was simply that you have FIVE approx 5000mah batteries 18" - 2ft further forward than where Al mounted just his TWO 3600mah packs to make it fly 'right' for him.

And it did used to need down elevator to fly inverted so I'm sure it just 'looked' better in flight because of Ali's 1000s of hours on scale jets made it that way!

Ali 04-12-2010 06:41 AM

RE: Skygate Hawk - build (virtual manual)
 
Getting old Mark????
There were a few strips of sticky lead in the hatch cover.
I do agree however that those lipos maybe a little too far forward. Maybe in the position that I positioned the Nimhs at would be a goods compromise.
Trust me, 1000's of hours or not, when I saw the Skygate fly when you had it at I could see it was really tail heavy.
Regards Al

marc s 04-12-2010 07:03 AM

RE: Skygate Hawk - build (virtual manual)
 
Cheers for the comments, ultimately the packs are all movable and there are loads of placement options, the two forward packs as I said are only held in place with the foam and this slides out as it is not fixed. Whatever is required to get the C of G right can be easily done. If only all the problems were as easy as this one!

marcs

Ali 04-12-2010 07:10 AM

RE: Skygate Hawk - build (virtual manual)
 
cool!

marc s 04-14-2010 05:40 PM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
Getting stuck right in now with the main instal, time has come to make loads of extension leads so out with the trusty connectors, cutters etc....

Made the two air intake lips from some white pigmented epoxy and glass and trimmed ready to fit once most of the build is complete to save damaging them.

Plumbed the UAT in, and the fuel shut off valve, this is on the opposite side to the smoke shut off and uses the same method of actuation via a small hole in the fuselage side M2 hex drive. The pipe routing has been kept to the minimum. One real bummer is the fitting son the UAT are for 8mm tygon, great stuff, the pump 4 inches away is 4mm, Mmmmm so 8mm to 4mm in 4 inches. Ended up as 8mm to 6mm for an little, then 6mm to 4mm for the rest - guess thats what has to be done but bigger fittings on the pump would be nice!

Solenoids are in too, mounted below the revised turbine rail.

Made two small mounting plates for the Powerbox LCD screen, Orbit programmer and Flugmodellbau lighting module, these are positioned in the void behind the rear cockpit panel so will be accessible when the canopy is open.

Mounted the equipment trays and offered up the ducting to make sure it still fits, and yes it does with only a few millimeters to spare....

marcs


marc s 04-14-2010 05:42 PM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
few more..


G.VITTINI 04-14-2010 08:38 PM

RE: Skygate Hawk - build (virtual manual)
 
Nice work Marc, looks stunning...I read the upgrades will be available thru Ali, put me down for the whole set.

Thanks

tassos p 04-14-2010 11:56 PM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
Marc,

I've been following your threads for a long time now. Very informative and very innovative. Well done and thanks for all the great ideas you're giving to the jet community.

I have a quick question-tip to make regarding the fuel system of the P200. I saw in the picture you're showing the fuel valve and the kero valve that you're using a Y connector to feed them. Have you tried this in the past with the P200?
I think this could cause air bubbles to build up and I'm talking from personal experience. When the pump of the P200 is pumping @ 6V or more the amount of fuel going through this connector is 730 ml/min. This has the potential of air bubbles being created in the Y connector and also a larger resistance than usual.

Instead I'd recommend a T connection (pic #2) so that you have a straight line with no obstructions when the fuel is travelling which causes less resistance at the pump's full speed and thus it is less likely to cause an air bubble to be formed. And an even better solution would be a barbed T connection as my #3 picture here bellow. I know the barbed connection is not as versatile as the festo fittings but I think it is more robust.

Once again thanks alot for all your great ideas and innovations.

Tassos


marc s 04-15-2010 12:31 AM

RE: Skygate Hawk - build (virtual manual)
 
Thanks guys,

Mr Vittini you will have to chat to Ali, we are finishing the fist five sets within the next few days so should be shipping these next week to interested parties.

Interesting Tassos, seems logical to me what you are saying, before I re-do this does anyone else have any experience or feedback on the current Y connector verses the T?

marcs

shaun1 04-15-2010 03:11 AM

RE: Skygate Hawk - build (virtual manual)
 
Mr Vittini,

Should you want to proceed with ordering upgrades they are exclusive through Al's Hobbies, please contact Ali direct - [email protected] where he will be happy to help with your requirements.

Marc, keep up the superb work!

Regards,

Shaun

marc s 04-21-2010 05:14 PM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
Lots going on which is not worth pictures or info, but have cut new strakes in the FR4 board to replace the more fragile plastic ones supplied, and my cnc guru is now making cad files to cut the wing fences and smaller items supplied in plastic in the SG kit in FR4 as well, these items will be much more durable than the originals, I have a few builders who have asked about these so if there any of you are interested in these upgrades let me know via PM and I will arrange to give you a cost and cut a few sets out to ship.

Started on the canopy tonight, a job I am not looking forward to but its got to be done. The Hawk will get the Details 4 Scale side hinged conversion, but before starting this part I wanted to work out a good secure latching system as the pneumatic system was not opted for. The kit supplied uses spring loaded hatch type pins which are fine, but having recently used a neat system on a PC21 I built I wondered if the same system could be used here. After a few drawings I came up with an idea along the same lines. A 'striker' plate made to slot into the channel in the canopy frame carries 3 slots for matching 'hooks' which will run inside the fuselage edge, retained by a spring holding the 'hooks' locked into the 'striker' plate. The canopy frame was sanded inside to get a good key, and the little lugs made to fit into the 'striker' plate to add fixing area and follow the inside frame contour were sanded along with the 'striker'. The lugs were cyano fixed to the 'striker'. I applied a bead of Aeropoxy to the inside edge of the canopy frame and where the lugs locate, and positioned the canopy frame over the 'striker' which was flat on the work bench - after making sure it was flush to the canopy frame base I clamped the unit to the bench to let the Aeropoxy dry.

marcs


marc s 04-22-2010 01:30 AM

RE: Skygate Hawk - build (virtual manual)
 
Sorry the last post would not show, had to add this to get it to kick......

marc s 04-22-2010 02:02 AM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
'Striker' plate fitted into the canopy frame rail...

marcs


marc s 04-23-2010 05:57 PM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
Just a quick update on some of the re-worked plastic parts cnc'd in glass board, rear strakes, wing fences, elevator cover plates and soon to be with me the various antenna and plates. I have had some interested parties in these sets as they are more durable than the ones supplied, so I'm getting 5 sets made up for those interested.
PM me if you want to know more.

Most of the wiring is now installed, just need to terminate the ends to the correct length, wiring the lights currently for the fuselage and cutting and making the bases for the supplies plastic light covers.

marcs

marc s 04-26-2010 03:03 AM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
Main work on the canopy is now underway. The 3 point larch bar system I have made to fit this jet was copied from the system used on a recent build, its very simple and very secure, plus I think with large canopy items to have three points of security is no bad thing.
The striker plate is already fitted inside the canopy frame, so it was time to fit the latching bar, this is sprung loaded to always engage the 'locked' position, achieved using a spring from the good old assortment box! The latching bar is heavily lightened so needs to run on a flat support, this is done using an L piece of thin light aluminium, the three fixing slots are marked and drilled through the aluminium, as well as a notch for the spring to run in.
I taped the canopy frame in place, added a few shims to raise it slightly to allow for paint and such like, and tested the alignment, to get the latch bar to fix to the fuselage side a few balsa blocks were glued to the aluminium and profiled until the fix was nice and square, once everything looked good I fixed the latch bar using some 5 min methacrylate as a first fix, this was allowed to go off, I then removed the canopy frame and checked the mechanism for freedom and general operation before fixing with 30 min methacrylate.
The latch bar is operated by an M3 cap headed bolt, mounted through the fuselage side, the head of the bolt is positioned in a natural 'hole' moulded in the fuselage side just behind the nose hatch, I added a collet, flatted the bolt shaft where the collet grub screw would normally fix, and replaced this grub screw with a steel turn buckle end, the hole at the end of this allowed a clevis and a short length of M2 threaded rod to connect to the front of the latch bar where provision has been made to fix another clevis to.
The operating bolt was mounted through a small brass plate which I glued and screwed to the top of the battery ply plate already in the fuselage.
A 1/4 turn of the bolt head, from outside the fuselage releases the canopy latches, so removal can be made without opening other covers or hatches. I will add a safety wire connection too which will terminate in a location that can be accessed should the linkage break of fail to open.

marcs


marc s 05-01-2010 03:31 PM

RE: Skygate Hawk - build (virtual manual)
 
1 Attachment(s)
Not wanting to put a fine point on this, but I have to say the installation of the side hinge system has been a real challenge, hours of head scratching and testing to see what might work.
Before I explain how I have installed this system I have to say the Details 4 Scale kit is good, it just seems the moulding for the inner cockpit frame is just too small to allow it to be installed as suggested.

The D4S kit shows how after mounting the supplied hinge posts into the fuselage, with the flat faces flush with the fuselage outer skin, the canopy inner frame will then allow you to fit the hinge blocks inside it - unfortunately due to the dimensions there was around 5mm between the frame outer edge and the fuselage side, the holes for the steel pin to run through was ending up outside the canopy frame. I re-think was required to get the hinges to work.

In the end I decided to try to run the wire pin through brass tubes, these seemed to rest roughly on the outer face of the canopy frame, the question was would the canopy open without fouling if done this way. I had to test it first so shimmed the frame .75mm (1/32) tacked the brass tube in a few places and tried the canopy, all seemed to work and no binding!

So knowing this part worked I cut brass tube into lengths, so they fitted exactly in between the hinge posts, I omitted a brass tube on the last rear section of the canopy as you have to bend the steel pin slightly to get it out, a brass tube glued here would prevent the pin retracting and the canopy being removable. Next came the gap problem, the brass tube once fitted to the side of the canopy frame allowed the outer frame moulding to line up flush with the fuselage, but if the canopy plastic was introduced between the inner and outer frame the resulting extra thickness pushed the outer frame past the fuselage edge, and this looked all wrong.

Eventually I decided to cut the canopy plastic short so it finished just above the brass tube. After doing this i noticed that the canopy plastic would now seat in a position which left a sizeable gap between it and the outer frame. Next fix involved cutting down some balsa strips to the correct thickness to keep the canopy plastic the correct distance from the inner canopy moulding, and positioned so it rested close to the outer frame. I also added a balsa shim the same thickness as the brass tube at the base of the inner frame to give the outer frame a flat surface on which to be glued to.

After all this I had a system which seems so far to work, tonight I have started to fix the canopy plastic to the frame (whilst in situ) so time will tell if all keeps going to plan.

I decided to omit the carbon plate supplied to strengthen the hinged side of the inner canopy moulding, and replaced it with a thin plate of FR4 which fills in the underside of the inner frame and keeps it looking like the latching side - this was glued into place after fitting two thin balsa stips along the inside edges to give a lip onto which the FR4 panel could be glued flush to the base. The result is a very rigid frame.

Its been a long week, but hope this helps out others who come across the same problems.

marcs



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