RCRCM Typhoon Build

[Peewhit]

Hi folks,

That kind Santa brought me an RCRCM Typhoon.

Looks "cool" in the snow.

 

This is my first mouldie and I will probably make lots of mistakes, but I thought I would share my experiences with you.

 

Started with the fus which is very tight and does need some careful planning.

Also wanted to see if I could get a fifth AA battery cell in as with six digital servos (and Spektrum 2.4) I would prefer 6v as opposed to 4.8

Sorry about the out of focus picture - have now found the macro button on the camera.

These are the bits of spruce which I epoxied under the deck to screw the servos to. Before gluing them in I brought the two halves of the supplied wiring harness through under the deck as there would not have been much space to do so afterwards.

The servos need to go as far back as possible and, to save even more space, I mounted them crossways.

Measured the pushrod movement (two carbon tubes in this beast) needed to give the required all moving tailplane and rudder movements, epoxied the supplied M2 threaded rod into the pushrods, screwed on the clevices and connected the servos up.

The holes in the bulkhead did need making a bit bigger for clearance as the pushrods move slightly across the fus when the servos are operated.

 

 

 

[Tim Mackey]

Lucky boy.... I want one

[Peewhit]

Now for some nose weight and that fifth battery cell.

 

Spent several hours making a wood template of the nose under deck, dunked it in a cut off beer  can filled with sand and pushed a copper pipe in the sand to represent the battery.

Melted some lead on the wife's gas cooker and this is the result.

The copper pipe was stuck in the nose weight but thanfully with the gentle use of a heat gun, it came free.

 

Battery and lead together weigh 5oz, so will need 2-3oz more lead on top of the deck.

And it even fits.

Took a five cell 2000 MAh Eneloop battery apart - the cells were hot glued together so got the heat gun out again, and reconfigured it to a square four plus one.

 

The switch is going directly behind the battery so I soldered it directly onto the battery to save on the spaghetti of wiring.

Here is where things get interesting as I made a mistake and soldered the charge wires on instead of the battery ones, and nothing would work - no power at all.

There must be some form of circuitry in that Futaba switch, and after an hour of testing with a circuit meter, I discovered what I had done wrong, and yes, the air did go blue at times.

Soldered the battery connection wires on instead and perfect.

Charges up OK too. 

I would have thought that both the battery and charge wires would go to the same connections on the switch and therefore it would not matter which one was which - apparently not!

Edited By Peewhit on 07/01/2010 14:45:23

[Peewhit]

It took a bit of hinting Timbo and it was a combined  Christmas and birthday present!

[Peewhit]

Battery and switch in - forgot that macro button again

And this is the almost completed job.

Spektrum 6200 receiver crossways between the switch and servos with sattelite unit under the pushrods.

This is the extra two ounces of lead needed to get the CofG at 85mm behind the leading edge.

Epoxied on and wrapped with insulating tape just to make sure it doesn't come loose.

 

And this is my baby all balanced up

I have put the wing servos in but that was before I found the macro button, and I used Z-bends to connect the pushrods to the servos.

Not happy with this as there is too much slop in the linkage, so I am going to redo with clevices at each end, and will then post some more pics.

Waiting for clevices and threaded stud to arrive.........

[Tom Satinet]

looking good.

 

good thinking with the battery. that shaped piece of lead is a good idea as well.  

[Peewhit]

Design, design, and more design Tom, plus a bit of inspiration.

How are you doing with your holes?

[Tom Satinet]

fine thanks. did one last night. filled and redrilled.

 

I've taken a step back. I wasn't happy with the ball links on the servo horns. the hyperion servo horns are really poor (very weedy even on the 095amd) and they were just too thin to support the balls. I have bought the hyperion programming lead to reduce the throws on the servos so I can use a longer arm and use clevises. I've had the servos out to move them slightly to accommodate (and change the arms obviously).

 

it annoys me that they send out the 095amd (4kg+ of torque) with servo horns with tiny holes that are close together. I mean if you need a servo with over 4kg of torque you are not using a bit of 22swg wire as your pushrod are you.  Not when you are trying to compete against futaba s3150s and the like.

 

 

what are your fuse servos?

Edited By Tom Satinet on 08/01/2010 09:26:30

[Peewhit]

Hi Tom,

 

Fuse servos are Savox SH 0257 as they are just the right length (or should that be width?) and also the right height to line up exactly with the pushrods. Torque is 2.2kg which should be enough for amt or rudder.

 

You are very brave to fit ball links onto those skinny hyperion arms!

 

They look a bit like Multiplex fittings to me. When I take mine out to fit the clevices which still haven't arrived - don't think my postman likes the snow - I will try a Multiplex arm and let you know.

 

Had to reduce my aileron servo throws to 50% so perhaps my arms are a bit long, yet they still fit under the servo covers.

 

You can get super strong arms for Futaba servos so why not Hyperion.

 

Having said that, the Hyperion seem superb. They center beautifully with no play , and are fast and positive in action.

 

Much snow down your way? My father lives near Worcester so may be worth a trip.

 

[Tom Satinet]

yeah pretty snowy and very cold........ brrr  Do you slope near worcester?

 

Yeah the servos are good except the horns. I have bought the programming lead. I will decrease the throws and the deadband.

[Peewhit]

Don't slope near Worcester as normally it's a one day trip and have to spend time with my dear elderly Dad.

Think that the Malvern Hills is the nearest decent place.

So where do you fly?

 

Clevices arrived today so have made a start on the flaps.

Servos were set up for z-bends so are slightly out of line for clevices.

 

Have 90 degree down flap for crow with no problem. Just rake the servo arms forward a bit.

 

Discovered that the flap wipers can catch on the wing when returning from 90 degrees.

Makes a big bang and could possibly dislodge a servo.

They need the front edge sanding smooth and a 45 degree bevel on the top edge to prevent this.

[Peewhit]

I can't believe this!

 

Redid all four wing servos with clevices at both ends of the pushrods as opposed to z-bends at one end - no slop at all now - pics etc t/f.

 

Was setting up the wing nicely with crow on flaps and ailerons, and ailerons working with flaps to give full wing camber.

 

Dead chuffed as I unexpectedly had two programmable mixes left on the DX7 which I used to link the flaps to ailerons  thereby increasing roll rate, and one flap servo started to jitter occasionally.

 

Then it jittered more occasionally, then it would only move in one direction, then not at all.

 

Plugged it into another receiver and it was absolutely dead.

 

Of course it is one of the two most expensive servos, so now need to go back to the supplier for a replacement.

 

Maiden flight deferred for the while!

 

[Peewhit]

Started the wings with the flap servos and decided to use the supplied servo mounts.

Think they are designed  for Hitec (5)125s as they needed a bit of trimming for my Hyperion 095FMDs and the pre-drilled pilot holes did not line up with my servo mountings

Needed to angle the bottom left side to give pushrod clearance and grind off a bit of the pocket edge in one place so that the screw would go in.

 

The pushrod also needed a slight bend at the flap end to clear the trailing edge spar and some grinding of the clevice at the servo end in order to clear the servo spindle when fully forward

 

All connected up and ready to go.

 

I originally  used z-bends to connect to the servo and found there was too much slop.

 

Hence when replacing them with clevices the servos are mounted slightly too much to the left - a bit too late to break the epoxy holding the mounts to the wing but they do seem to operate OK.

[Peewhit]

90 degree of flap for crow braking is not a problem, and the other flap works too

This photo was taken before one of the brand new flap servos packed up - the replacement should arrive soon!

 

There is not much depth of wing at the aileron servo pockets and you need a really thin servo here

I opted for Hyperion 090AMD as they are only 9mm thick and fit nicely.

The mounting brackets are vertical and they supply some nice clip on plastic bits and rubber grommets which convert to a horizontal mounting.

 

They are simply screwed to two pieces of epoxied on plywood, and for a "belt and braces" approach have a dollop of aquarium grade silicone sealant underneath them.

 

This was far easier than the flap servos  and the pushrods can be straight although there is not much space between the two clevices.

 

Next job is to replace the faulty flap servo, then on to the electronic trickery bit.

 

[Peewhit]

Well it's all done.

 

Faulty servo replaced and after much research and head scratching the DX7 is programmed.

 

Have managed to achieve:-

 

Ailerons moving with flaps to give full wing thermal and speed settings

 

Flaps moving with ailerons to act as flaperons and increase roll rate

 

Crow braking with flaps down, ailerons up and elevator compensation.

 

If anyone wants the details send me a pm

 

All I need now is some decent weather to maiden it in

 

Mental note - must do a range test first!

[Tim Mackey]

Nice one PW...yes please send me the details - save me hours of fiddling that will

[Peewhit]

Ok will try and make it as brief as possible.

 

The basis is the setting of ailerons as flaps/ailerons using flaperon mixing

 

Set up flaperon mixing for ailerons ie right aileron into aux 1 and left aileron into aileron

 

left flap into throttle channel.

disable gear switch by setting gear servo travel to 0,0

right flap into gear channel

PMIX 5 (so that flap trim levers will work) throttle master to gear slave - both flaps now work off throttle stick.

Use throttle servo adjust to set left flap movement and PMIX 5 settting for right flap movement.

 

crow braking - PMIX 2 throttle master to flap slave - both ailerons now travel the same way off throttle stick - note offset value of +100% needed

PMIX 1 throttle master to elevator slave -  gives elevator compensation - offset vale of +100% also needed.

 

thermal camber and speed reflex using 3 position flap switch -  I use down for thermal and up for reflex 'cause that's the way the surfaces move - set up required aileron movement using usual flap %ages

PMIX 3 flap master to throttle slave to set flap movement - the interesting and nicely surprising thing here is that both flaps move. I don't know why. could be something to do with the fact that they are linked on PMIX 5?

Anyway, it saves a crucial PMIX which leaves two free for flaperons.

 

Flaperons (flaps moving with ailerons)

PMIX 4 aileron master to gear (right flap) slave

PMIX 6 aileron master to throttle (left flap) slave

 

Bingo - it works

 

All donations please to McMillan Cancer Research

 

[Tim Mackey]

Cheers - well done

[Peewhit]

Feel free to copy and make a donation.

 

Time for bed now

[Stefan_L]

Hi, please give me a short statement about the quality of the painting. I read in a German forum that the surface quality of planes from RCRCM is not so good.

 

Also some issues about the spar in the wing, some space between spar and upper / lower part of the hull.  Some space between and not complety glued. Do you have the same on your Typhoon?

 

Best wishes from snowy Berlin

Stefan

[Peewhit]

Hi Stephan,

 

My Typhoon seems to be reasonably well finished.

 

It was unpacked and inspected by Ian at Sloperacer before he shipped it to me.

 

The wing seems fine and, having further inspected it after your post, there are no gaps and everything seems to glued down nicely.

 

I do have two very minor paint blemishes on the tail, but you have to look very hard to see them.

 

For the price of the Typhoon, which includes bags and wiring harness, I cannot really complain as many much more expensive mouldies also have some paint blemishes.

 

Greetings from snowy (no longer) Yorkshire

[Peewhit]

Two lovely chunks of 20mm brass rod arrived today from e-bay.

I tend to have two stages of ballast in my slope soarers - all or nothing!

 

The ballast tube on the Typhoon is not placed centrally. There is more of it forward of the C of G than aft.

So if I were to fill it completely, the Cof G would move forward and I firmly believe that the C of G should not change with ballast.

 

Put a chunk of elapor for cushioning at the front and back of the ballast tube and then measured what was left in relation to the C of G.

 

 

Six 40mm lengths of brass rod will give 120mm of ballast each side of the C of G with a wooden spacer at the front to stop them from sliding forwards.

 

It fits a treat - nice and rigid in the ballast tube with no longitudinal movement and the elapor to (hopefully) cushion and stop the ballast  smashing into the fus servos with a rough landing.

 

Total weight of the ballast is 24oz which by my maths is a pound and a half.

 

Job finished and I knew those nice plastic boxes that the Savox servos came in would prove useful.

[Tom Satinet]

Hi Peter

 

glad you got your typhoon flying.  24oz ballast should give you lots of range I reckon.  It sounds about right.

 

Looking forward to getting mine flying although I have a couple of other models to fiddle about with first before I get it done. 

 

What's your second mouldie going to be then??!!!

 

Tom

[chrispy]

Hi, very neat you integrated the battery with the lead balance. Can you tell me where you bought the  five cell 2000 MAh Eneloop battery ?

Many thanks,

Chris.

[Tim Mackey]

Try HERE