Hi Gerald,

Yes, it's 27 lbs, with a JetCat P-120. Not sure of it's flown yet - if you'd like to 'talk' to Ted, I can PM you his email address...let me know.

Cheers,

Dick

I spoke to Ted yesterday. He was held up by ECU probems, now sorted and ready for test flight as soon as weather is good. Mick

Since the support ring is on the section that would have to be cut off, there's a bit more to it than just trimming the pipe - I would need to have a new support ring made and welded on too ... and then I'd still just have a single walled pipe that I'd spent extra money to make it fit, rather than a dual wall pipe that perhaps won't cost me a whole lot more.

We'll see though - the jury isn't in yet on the single vs dual-wall decision. If I do end up going dual, I'll post weight comparisons here.

Gordon

FWIW, all my models have been equipped with a single walled pipe, with and without full-ducting system, no problemo ever!
I had a chance to do a comparison test with my Avonds F16 where I home made the single pipe against a standard Avonds pipe, the difference was marginal where the back fuselage warms-up just a bit when prolonged parked with engine in idle, no big deal however. I also had some hot starts occasionally where the time versus internal airflow is just too short to warm-up the fuselage.

I don´t see any reason why using a double walled jetpipe as for the weight gain. I can however understand the somewhat secure idea for those new to jet-flying and those who doesn´t understand aerodynamics. When improperly installed a single walled tube could heat up the fuselage substantially, it´s the correct internal flow that makes the big difference. Therefor I can also understand why jetpipe manufacturers are mostly making double walled types where there is less risk that a customer could screw-up the installation and hence a hot fuselage.

The choice is really up to the builder of the model, just want to get rid of the tendency that a single walled pipe is per definition a bad idea!

Regards,
Gerald

A doublewalled duct will weigh twice as much and cost more than twice as much as a single wall. Post your duct to me and I will shorten it at no charge.
Mick

Hi Gordon

I'm a little puzzled with your reference to the support ring on the pipe you have for the Hunter, on mine the support ring isn't welded on and is free to slide along its length. My pipe was also a little longer than required and I have trimmed it to size so it sits 3/4 inch inside the rear fuselage with the bell mouth mounted at the front of the rear half of the fuselage. Even though the pipe is divergent and I had to cut off, from memory, about 2 inches there is no play at the support ring and I have lagged the pipe with ceramic blanket.

IB

Dear All
We had to do the same as IB has done, with the Lightning, the ring is free sliding.
The pipe was to long we did actually fly it like that.
On the advice of Tom Wilkinson, we trimmed it so it sits about 12mm inside the ring.
There a couple of pics below, trimmed and untrimmed.

REgards Phil G.

Mine is definitely welded, so it;s possible that Mick may have changed methods a bit at some point. It's really not surprising when stuff like that happens, since I apparently got the very first kit, and some changes are to be expected as any kit "matures" (same kinda deal happened when I got a very early kit of the BVM Super Bandit).

I'll enclose a pic to show that the ring is welded in place, but I'm afraid that my camera doesn't do too well at close-ups of shiny material so it may not be very clear.

Any idea how much weight the ceramic blanket added ?

------------------------

Mick - thanks for the offer of reworking the pipe for me... if I was "local" I'd possibly take you up on that even though I don't know for sure yet what my pipe plans are - but shipping the pipe all the way from California to England and back doesn't seem particularly cost effective when I have a pipe specialist within about 6 miles of me. For anyone else who doesn't have a Tampipes business right on their doorstep though, I'm sure your offer would be much appreciated. Thanks.

BTW, a dual walled pipe apparently doesn't have to weigh twice what a single walled pipe weighs. In fact, when I showed Tam this pipe while he visited my workshop last year, he commented that it seemed a bit on the heavy side for a single-walled pipe and he stated that he could make me a dual walled one that "wouldn't weigh a whole lot more" ... now, to be honest, how much of that may be sales pitch from him, and how much may be reality I have yet to discern - but if I do choose to go down that route I will be sure to post weight comparisons for anyone who is interested.

Later,
Gordon

When we started making jet ducts, we used 0.1 mm stainless steel. We found this was a bit flimsy for the more powerful engines now being used, so we changed to 0.15 hard stainless. The hard material is much stiffer than soft annealed sheet used by some. The hunter duct weighs about 320 gm. Mick

Hi there Gordon.

I run a hobby outfit in New Zealand ... Airsail ...and have had a bit to do with Mick ...sell some of his kits. I've just started a Hunter and I'm interested in your assessment. Already there' a few things that I'm more than a little unhappy about, but I guess when it's all over the "breach birth" will be forgotten as it promises to be a beautiful model of a beautiful aeroplane. There are some very, very good things about the kit, particularly with regards the wings. The same can not be said about the fit-out of the fuselage.

I've used ProSkin on a number projects and you wont be sorry. It's advantage becomes very obvious when you get to the finishing.

I'll keep an eye on your progress.... Cheers ...Brian Borland.

Impressions so far are that overall the kit is pretty much what I would expect from a "cottage industry" manufacturer - some high quality stuff, some lower quality stuff, some well thought out areas, and a number of areas where things simply have to be reworked (in my opinion) in order to get the kind of quality / durability / etc that I personally feel comfortable with. Some of these are very subjective areas, of course, so there can be considerable disagreement on those topics.

An additional factor that I have to take into account with my particular kit, is that this was supposedly kit #1 according to Mick - and so some of the little "nigglies" that I see in my kit (e.g. the nose-gear has no steering mechanism - I will need to make up my own) are to be expected to some degree - See my BVM Super Balsa Bandit review where I found and reported a number of small errors - even though BV totally has his act together and can put more time & effort into his kits since he's looking at considerably higher volume than Mick, there were still a number of little things that were wrong in that very first batch of kits. In other words, I don't know how representative my #1 kit is of the others.

Obviously, since I'm not finished yet, there may be some patches of quicksand still ahead of me, but - if I had known, when I was getting ready to buy this kit, what I know now - would I still have bought the kit ? Defintely, yes. I certainly wouldn't have bothered with the drop-tank kit, and I would have looked around to see if I could find another source of the landing gear, but I'd still have bought the rest because there's still more that I like about this kit than there is that I dislike about it. Sadly, some people here can't see that, and repeatedly focus only on the negative aspects that I report... but such is life. I don't whitewash any of the reviews / build-threads I do - I tell it just like I see it, and I've paid good money for the right to have my opinion ; others are of course perfectly welcome to disagree and post their own praise for things that I don't like, or their own disdain for stuff that I do like. This is, after all, a discussion forum - not an agreement forum - and IMO it's better for customers (or prospective customers) to see multiple opinions than none at all.

OK - just don't hold your breath. I seem to have so many other things going on, that I simply haven't spent any time on the Hunter for ages. The fact that I just changed jobs a few days ago promises to further add to the list of things that keeps me out of my workshop...

For the areas that you say you are unhappy about - feel free to post details (or if you don't have Nomex underwear, send me a PM) - if its anything that I've come across and have some ideas on I'd be happy to share. Mick may also be able to make suggestions here.

Later,
Gordon

One improvement we recommend is to fit tubes in the fuselage to take the aluminium main wing tubes. These can be made by wrapping some Pro-Skin around the alloy tubes. These are then glassed into the fuslage to give a durable snug fit.
The elevator drive system supplied in the kit wortks very well, and avoids having non scale external horns etc. Some builders are frightened by this and change it, OK , no problem.
Mick

Earlier, it was suggested that a dual wal lpipe would weigh twice what the single-wall one that came with the kit does, and it was also suggested that instead of dealing wit hthe extra weight of a dual wall pipe I should consider just wrapping the single-wall pipe with a ceramic blanket..

Well, those weight estimates now appear to have turned out to be considerably off... I had Tam make up a dual walled pipe for the Hunter and it came in at 410g ; by comparison, Mick's single walled pipe weighs 340g - so if I used even 70g of ceramic blanket with the single walled pipe, I wouldn't be gaining anything weightwise. Note also that the pipe Tam made for me has a larger diameter to suit the chosen P120 powerplant (you may be able to see the diameter difference in the enclosed pics), which means more material and more weight - so in other words if he had simply made a dual wall pipe to the same dimensions as the original single-wall pipe, the minor weight difference would have been even less.

I also had Tam add a 3rd strap to the front of the pipe to aid in holding it in place, and I added a thin plywood doughnut to position & support the tail end of the pipe.

Hey Gordon:
Who's little Doggies are those on there tippy toes

Dave

I've also added the Sabrinas now. I don;t know who Sabrina was, but she must have been a buxom lady, since the "Sabrinas" are rounded bulges that protrude down from the fuselage. They were used for collecting the spent shells from the aircraft. Here you can see the Sabrinas added & faired in, as well as some added scale factor via the brass tubes.

I have considerable experiance wrapping pipes in ceramic blanket. DON'T DO IT. Two things, the ceramic blanket browns and starts coming apart, and it retains a lot of heat insulation wise, which helps it break down further.

I tried multiple variations including wrapping a pipe in aluminum foil, safety wire, ceramic blanket on the outside, more safety wire and aluminum tape, you name it I tried it and none of it worked.

The only person I know personally that has had success with single wall pipes is Eddie Weeks and Marc (Woketman). Both of them are considerably smarter than I, and neither used any ceramic blanket at all. I bought a roll of ceramic blanket around 400 square feet for 85 bucks a year ago in anticipation of using some. I ended up shipping it to Todd at Dreamworks and telling him to sell it off. I did however get a beer or two out of the deal and that was worth it to me.

Oh, and some experiance, ceramic blanket does burn

Finished the engine mount ... here I'm using the same BVM mounts (for the P120) as are used in e.g. my Bobcat. You may notice that the engine sits fairly high up in the fuselage.

Here's some pics showing the cannon troughs being created & installed. - basically just cut out the desired outlines in the fuz skin, laminate some balsa to the necessary depth and use the trusty Black & Decker Minicraft to shape the cut-out, then glue the part in place. Repeat as necessary for the 4 cannon.

Next is the engine hatch; needed some manner of locating the sides properly, as well as retaining the hatch once it's in place. For locating, I chose to use some BVM hatch pins.

I had initially intended using a couple of BVM hatch latches too - one either end - and had actually cut the slots for them when I saw a wonderful idea on an A4 model that Tam had at one of the jet meets (Fresno ?). I think Tam got the model from someone else, so if anyone wants to claim bragging rights for the idea, feel free. Anyway, I chose to use a variation of this idea since it is a very clean mechanism. Basically the idea is like this. A small hole is made in the top of the hatch, that is just big enough for a ball-driver to pass htrough. Underneath that hole, we mount a small plate that has a servo arm with a cap-head screw (to match the balldriver) glued to the arm (the second pic shows the arm etc, with the screw facing downwards just so that you can see the mechanism, but in reality it will face upwards once we're finished).

Attached to each end of the servo arm is a pushrod which goes through a guide channel then out the end of the hatch sides, protruding just as the pins from a BVM hatch latch would. Wheel collets are added to the pushrods, to retain and compress a couple of springs that will ensure that the pushrods will push outwards and lock in place. You simply insert the ball-driver and rotate it to place the springs under compression when you want to remove the hatch. A small end-stop (not shown) also had to be added to the servo-arm mount to ensure that I could not over-rotate the system and cause the pushrods to move so far that they came out of their guides.

Gordon--Lookin' good!!! 'Bout time you got crankin' on that bird again!!!---One word of advice--The next time you take a pic make sure you hide those big feet!!!

Kevin

Gordon, can you describe in more detail what is holding the servo arm to the piece of hardwood? I get the 4/40 or whatever, I don't get "glued" to servo horn. Is that a nut on the other side of the screw? How tight if so? Just tight enough that it will turn? Assume too tight and it won't turn? So the glue is to keep the servo horn locked to the screw?

What a neat idea, but sure looks like about 5 hours worth of work!

Fuel tanks.... I bought the 3 litre tank as an extra to the kit - it's the soda-bottle shown below - but I personally have a bit of a dislike for soda-bottle tanks since I just feel that they are more prone to bursting than goold old Kevlar etc tanks. Also, the 3 litre soda bottle has no baffles in it, so that sloshing of fuel occurs easily. I'd seen a magazine article or two on making your own fuel tanks, so I decided this was a perfect time to try this for myself.

First I had to make up some foam shapes representing the tanks. I decided to make up two tanks, shaping them to fit the underside of the fuselage and to fit around some bulkheads. I also wanted the vent lines to be on a "bubble" on top of the tank to ensure that the tanks really fill befor ethe overflow occurs (I've seen far too many tanks where half a pint or so of capacity is wasted due to the tanks not really filling). My first idea is as shown in the pics where tere is a balsa "bubble" attached to the foam.

LOL ... I'm just glad I can see my feet ... 3 weeks ago I was 14 lbs heavier and all you would have seen is my big fat belly. Also, since I was nekkid when I took the pic, maybe you should be glad that it's my feet that you see !

Yup - we want the servo arm to always rotate when you turn the ball-driver (otherwise you could be in a real mess if the screw keeps on turning and you suddenly have no way of getting the hatch off!!), so the cap-screw is simply glued to the arm to ensure that the arm will rotate on demand. If I recall correctly I actually glued a small nut on to the bottom of the servo arm too, I used Pic Plasti-stic to wick into the joint, then used Aeropoxy to make a fillet to hold everything tight.

The plywood plate is just there to hold the servo arm in the right position for you, so you want a tight clearance fit drilled through, then a washer & nylock washer on the other end that is tightened up enough to ensure that the assembly won't slop around, but loose enough to allow the screw to rotate when required.

That hatch latch system is S-L-I-C-K!!!!!!! Just when you think you've seen it all someone comes up with a better mouse trap. I'm archiving this one!!! You've done lots of work on this plane w/lots more to do---Keep at it as it looks to be a winner!!! Many of the "modifications" that experienced modelers take for granted really help the newbies---Keep up the good work---Even those of us like myself that have been modeling for years can learn a thing or two....Now---More pics please!!!!

Kevin