RE: Skygate Hawk - build (virtual manual)
 

Don't worry everything has been copied and traced, 4 hours on the carbon laminated plates alone!

Looks like I'm away skiing when the T hawk arrives with you so will arrange to pop over when I'm back after the 22nd.

marcs

RE: Skygate Hawk - build (virtual manual)
 

Tough life!

RE: Skygate Hawk - build (virtual manual)
 

Marc,

As usual great job and very well thought out. I do have a question about the gear door cylinders. Are the collars installed on the rod end to limit travel when using a actuator that might have more throw than needed? Very basic question and I think I have the answer, just fiqured I would ask. Thanks.

Jason

RE: Skygate Hawk - build (virtual manual)
 

Yes they are!

RE: Skygate Hawk - build (virtual manual)
 

Jason, as Mark said yes.
Most cylinders tend to never have the correct throw so adjust the opening at full stoke, then mount the cylinder fixing, then close to the correct point and tighten the collet up against the cylinder base, works a treat and allows very accurate closing position, I also tend to add a small silicone rubber washer between the collet and the cylinder - sort of cushions the last part of the throw.

marcs

RE: Skygate Hawk - build (virtual manual)
 

Thanks Mark and Marc,

That is what I was thinking and I am going to do the same thing on the Velox XL I am building right now. Picked up some Jet Model Products door cylinders (very nice units) when I bought his accumulator for my Booster 160. The throw is close but I did not want that pressure on the arm and hinges causing fatique and early failure. I appreciate it and really enjoy the builds. Take care.

Jason

RE: Skygate Hawk - build (virtual manual)
 

Marc,

What material are you using for these parts? Is it balsa core with carbon laminate or foam core?

David s

RE: Skygate Hawk - build (virtual manual)
 

David,

The formers for the turbine mount are carbon laminated ply, same thickness as the original formers but without the cut outs, significantly stiffer with very little extra weight. The rails etc are carbon faced 5mm ply, required around where the turbine sits but probably overkill in the forward tray areas. It was easier to make the piece as one so hence the major 'lightening'.

The tank formers (when the tank arrives) will probably be herex/carbon laminate, or end grain balsa/carbon - yet to decide.

marcs

RE: Skygate Hawk - build (virtual manual)
 

Quick update on the new tank, first one out of the mould, well half out to be precise!
Thanks go to Alex and his team at UKR for making it, and when fully tested and mounted in new formers it will be available via Als Hobbies, designed for the Skygate Hawk, Tomahawk Hawk and any jet needing around 6.3-6.5L (not sure of the final exact volumn yet)

marcs

RE: Skygate Hawk - build (virtual manual)
 

Typical you wait for things then just as your about to go on holiday the bits arrive!

Well ducts have had the final testing in the fuselage, and since the pictures are now sanded, primed and should be glasses today or tomorrow, the first prototype bypass is in, made from glass although the final version will be carbon, seems to be a good general fit but won't be able to check this for another day or so.

New air valves are due from Emcotec and the new fuel tanks are on the way as well!

Will update on return.

marcs

RE: Skygate Hawk - build (virtual manual)
 

Bypass resting on the formers, needs a little tweaking to get the positioning right, mainly due to the physical size of the P200, but we'll get there.

I was asked to fit as large as is possible air tanks in this jet, due to the large cylinders that are required to drive these large scale jet gear systems, I was handed 3 x 500cc tanks, with a view to ganging two for gear and have one drive doors/brakes. I made two ply formers to sit under the cockpit tray shaped for the tanks to rest in, they will be secured with either a clamp or springs (yet to be decided). Whilst on this topic I searched to see if there were larger tanks around and found it hard to locate any bigger units. The space available in the SG Hawk would allow for larger units so it seemed logical to try to fit the biggest possible to give the best air capacity - especially as they weigh very little.

My search led to tin tanks which were not ideal, but then finally by luck I received some sample 800cc units, so now 2 ganged for gear gives 1.6L of capacity and the doors/brakes get 0.8L capacity. I'm having screw caps fitted to accept a fitting to connect the 4mm air line to. In these bigger jets bigger air tanks seemed a good route, linking loads of smaller units could increase failure due to leaks etc.

Couple of pics shown against the 500cc units.

marcs

RE: Skygate Hawk - build (virtual manual)
 

Marc,

Good find. I'll take 3 samples for the Tomahawk. ;)

M

RE: Skygate Hawk - build (virtual manual)
 

Marc,
Unbelievable work!
Scott

RE: Skygate Hawk - build (virtual manual)
 

Nice bottles Marc,

I'm thinking of using these for my Tomahawk-Hawk.
What's the weight of these bottles?

Remco

RE: Skygate Hawk - build (virtual manual)
 

Remco, the 800cc cans are 72g each without the caps, I weighed the 500cc bottles which have caps fitted and they were 72g so I suspect the bigger cans once fitted with caps would be around 85g.

I will test them when they are back (along with some 700cc cans I also sourced) from cap fitting to see how many reliable cycles they give on the standard SG Hawk gear.

marcs

RE: Skygate Hawk - build (virtual manual)
 

Back now from a family holiday, ready to get stuck back in......

Been playing about with the air valves and sequencer to get the best position on the upper deck, after a few hours trying different locations for the three valves and sequencer I eventually settled on the current locations, this allowed most of the plumbing to head off in the right direction.
The unit complete with main door cylinders removes as a whole unit. I added 4 quick release air valves on the lower front face of the deck to connect up the nose gear and doors, there are also four Multiplex plugs to connect up batteries and nose lights etc on the same panel. One further quick release air valve on the upper deck will connect the air tanks to the system.

I was going to use two air tanks for the gear and one for the doors/brakes but as the sequencer has a safety air pressure connection I decided to keep all three tanks hooked up to the whole system, following advice from Emcotec the brake valve is connected to the gear down supply so it only has air available for braking when the gear is down, an additional feature which could prevent air leaks. I still need to complete wiring on this unit and paint it grey but its close to where it needs to be.

Got the first two ducts off the revised moulds and they seem to fit nicely, the two intake moulds required the lips levelling off, this was done buy mounting a diamond Dremmel disc into my mini router and clamping it in a vice so the disc was 1/2 inch or so above the vice jaws, the intake moulds were then rested on the jaws and this provided the height fence to allow a neat level edge to be cut around the intake lip.

Before fixing the ducts I needed to make the retaining system for the two intake moulds as these are to be removable to allow access to the turbine and smoke tank etc. I cut two lite ply formers to match the intake mating face shape, then glued each into the inside of the two intakes so they just rested on the pre-moulded hole locations for the location studs. I drilled out the lite ply to match the holes in the intakes and then mounted them to the fuselage and using M3 bolts drew M3 captive nuts into the lite ply, this provided a 4 point fixing for each intake.

Once I have finished these I will fix the ducts to each intake gluing when in the correct position.

marcs

RE: Skygate Hawk - build (virtual manual)
 

more..

RE: Skygate Hawk - build (virtual manual)
 

Keep this thread going chaps, mine arrived on Thursday. It would be an understatement to say I'm impressed, but NOT with the fuel tank, it leaks badly ! Otherwise its absolutely superb..
Regards, David Gladwin.

RE: Skygate Hawk - build (virtual manual)
 

I'd be interested to here your views on the elevator linkage David.

m

RE: Skygate Hawk - build (virtual manual)
 

Will do Mick, David.

PS My INITIAL impression is that it is a better system than Airworld because the two servos are not hard linked to the rigid stab and if one servo should fail the other, if the failed servo is locked as in a burn- out, locked, should allow a degree of stab. movement due to the geometry of the bar connecting the two servos.

I bought two JR brushless servos (MPT80) for this application anyone have any in service experience of these ?

RE: Skygate Hawk - build (virtual manual)
 

I hooked up the 2 servos on the elevator linkage and was suprised that there was zero bind without any work. The setup feels very solid and free from slop. I used a digital amp meter and it showed very minimal readings with the 8711 servos, even during deflection.
I kept debating moving the two servos to the tail as it would be such a simple setup and would get the rod out of my hatch! What a short pushrod it would need if the servos were in the back!
I made this nifty stand yesterday that I can use to put on wings and even cycle gear while its in place.
Scott

RE: Skygate Hawk - build (virtual manual)
 

Hey Scott,

Let's see some more details pics of that hatch?! That's the first SG Hawk I've ever seen with one!! Nice stand too - may copy that for my new TomaHawk Hawk.

Oh, and the debate of the elevator linkage can run and run and run based upon the type of failure and servo position at failure. The std setup is the best all round solution.

Cheers,
Mark

PS Do you have a bouncing u/c setup to go with those blue gangsta neons you've installed?!?! What are they? :D :D

RE: Skygate Hawk - build (virtual manual)
 

Hey Mark,
Those gansta neons are my big pimpin Fromeco regulators!!
Heres some hatch pics.
Scott

RE: Skygate Hawk - build (virtual manual)
 

Scott, great work on the hatch, as you can see from my post I wanted to add a decent sized hatch but it was muted it might reduce structural rigidity, the area where the RAT is on the FS would have been a good option as well - anyways like your work ;)

marcs

RE: Skygate Hawk - build (virtual manual)
 

Started working on the ducts, trimmed the leading edge lip to fit over the intake mould and have started to add the carbon tow reinforcement bands.
The intakes moulds are mounted via M3 bolts through the captive nuts fixed into the lite ply former, hopefully they should be all accessible once the ducting is in place although I suspect one might be a little bit tricky to get to but with a ball hex should be do-able.
Made up an air distribution manifold (cheers Rich ;)) where the main feeds from the valves will enter and then get directed to the main gear cylinders, doors and brakes - I used this system on the PC21 I recently built and found it made final connections very simple. I may change the push fit connections shown in the picture to simple barbed ones, but this will depend on what connections may require removing for servicing etc.....

marcs