xanaphyst

My Feedback: (17)

PROP SWEEP !!!

Larry Driskill

In my experience when using bladders with 1/2as the following are truisms.

1. Ideally, you need a fine thread needle. Probably about 100 threads per inch minimum. The KK (Kirn) needles for the TeeDee are 128 tpi. VAs are about 110 tpi.

2. You need a low pressure bladder. Thin wall latex works well. Thin meaning 1/32" wall. I have used 1/8 O.D. , 5/32 O.D., and 3/16 O.D. latex. The 3/16" gives the easiest settings, but all three work OK. The smaller tubing is easier to fit in small places. The 1/8 fills to about 5/8 diameter and the 3/16 to about an inch.

3. Don't try to use a bladder for very many fights before replacing. Also, the useful shelf life of bladders is weeks after they are once filled with fuel and used. Change them fairly often.

There is a longer rant on my website. Look under Tips and Techniques and Bladder Fuel Pressure Systems.

matchlessaero

Sorry to see that your delta went in...: ( but glad to hear you are reincarnating it!

If you still need pipe dimensions, I can help with that. Just send me a PM (got your other one btw)

Keep us posted on your progress [8D]

xanaphyst

My Feedback: (17)

Thanks for the info Larry...I got your order in very fast the other day...you have your "kit" together man !! It's looking like I will need the 1/8 tubing for my bladder tank needs due to the thin airfoil design of the Mini-Dust. My question is...Can the bladder holder be shaped so that it forces the bladder to fill in a more ovalish shape? As you can tell by the attached picture I'm assuming a carboard tube of 1/16 walls (Hence the 3/4 space and not 5/8 for the 1/8 tubing). The reason I ask about the oval shape is because I would like to move the bladder directly over the CG but the fuse is tapering down too fast to allow the full required space thus I need it to "squish" down a little. The word forward in the pic points towards the front of the aircraft.

Also...where can i get a fine thread needle setup for the norvel ???

combatpigg

My Feedback: (3)

I can chime in here, you DON'T want the bladder to get squished in any way by the compartment. This will lead to false needle settings, the extra pressure exerted on the bladder goes away after the bladder empties a little and it will leave you with an engine frying run. The best set up is to mount the bladder externally[ if your wing is too thin], if you do it "right" it will look like a canopy when the bladder is full. Another thing I have done is to turn a plastic canopy into a fuel cell, if[when] the bladder breaks, it's external to the plane.

xanaphyst

My Feedback: (17)

Well...the ribs, carbon rods, and engine mount are cut out.....I had a small epifiny and decided that the cure to my tail heavy problem is to incorporate the reciever batteries into the LE sides of the engine mount....the AAA's would be too long to use all 4 cells so I ordered some 1/3AAA NiMH cells that are going to do the trick....this will allow me to slide the servos much further forward. The weight savings of the smaller cells and lighter servos ( hitec 81 VS. hitec 55)are going to shave the weight down to 10.25 OZ !!! Lastly is the FMA reciever that this Dust is going to get. It features horizontal pin-outs and crystal, is very small, and is a full featured reciever..none of that single conversion park flyer stuff. The size of the reciever should allow it to be placed in front of the fuel bladder....Lastly I figure that careful selection of covering, changing the TE to balsa instead of spruce, and a few lightning holes in the control surfaces will have me on the money at 10 OZ or if I'm lucky a sub 10 OZ delta...
Hopefully I'll get these little critters down to a science before long....

combatpigg

My Feedback: (3)

10 ozs is excellent! Last time I checked the rule book for 1/2A pylon they had to weigh 20 ozs minimum[OINK!] No problem, if you want to race AMA rulebook all you have to do is tape something onto your plane that weighs 10 ozs, like 1/4" steel plate that measures 3"by3"! Let us know if you find the cause of the crash, it's always good to get a FYI if you got let down by bad equipment. With a 1/2A it is hard to get a plane to balance if the engine isn't sticking out somewhat, you've done a good job of getting all the heavy stuff in front of the CG.

xanaphyst

My Feedback: (17)

It looks like the problem was the antenna being rapped all around the batt. leads and servo wires before running out the back....my faithful assistant was kind enough to tell me the ailerons were jittering on each take-off before he released it...I noticed it did seem to take a few "hits" while flying....oh well....[:@]

combatpigg

My Feedback: (3)

I am sloppy about antenna routing, but don't have trouble with it. The DC power won't interfere with RF reception. If you had one elevon twitching, I would suspect the servo. If both elevons were jitterbugging, then it could be a loose connection in the battery pack, or somewhere on the power bus in the receiver. Problems like this sometimes only show up when the engine is vibrating the plane. I have to send a couple of radio systems back to HITEK to be checked out for the same reason. I doubt if they waste much time once they find the culprit, their cost for the components can't amount to much. I have isolated the cause in one of the RXs with the help of a magnifying lens, but there's nothing I can do about it, the tiny component has dislodged from the board and it is too tiny for me to solder back on[&o]!

xanaphyst

My Feedback: (17)

Well...I'm back at it with Ver. 2.0........The little 1/3aaa batteries turned out to be a little bit thicker than expected so I lined them up against the firewall and the fit looks quite nice so I'll leave them there. At 210 mah and 1/2 the weight of my other batteries I think they are great !! Just like last time I have overlooked getting a needed servo . I'll also be waiting on my reciever !!! I built in the downthrust on the firewall this time to avoid having to put washers under the rear mounting bolts and flipped the colors to white over red because the red bottem should be easier to see than the white..or maybe not I guess we will see....

Stay tuned !!!!!!!!!!!

xanaphyst

rscarawa

Where did you pick this kit up? Or is this a diamond dust that you scaled down yourself?

xanaphyst

My Feedback: (17)

The mini-dust is not a kit..but a set of plans from Winger models...but not a very good one due to the CG problems and if you built it according to the plans it would take a pound of lead to balence the thing. That being said I like the challenge of working around it's quirks and they are very fast !!

Check out the pic !!!! Maybe I'll put the JB weld away this time and do it right..... AME/BSE/RE 061 norvel (that's a lot of E's!!)

xanaphyst

My Feedback: (17)

Allright PIGGY.....It's on now....I had to go upstairs and get some work done after reading your post...so here it is....flight report should be this weekend if the hurricane doesn't wash my house away first...You can see the inflated latex bladder...very low profile bladder ....great for the delta....and the hatch to the right...had to hatch it so I could change out the bladder as needed...

combatpigg

My Feedback: (3)

Lookin good DUDE! I have to point out that the bladder needs to be in a liquid tight compartment for if/ when it breaks you don't want an oz of fuel running around loose inside the plane. The bladder compartment can't press against the inflated bladder either, or you will get a false needle setting, and then wonder why the engine went lean 1/2 way through the run. You have to design the compartment around a bladder that is full of liquid [just use alcohol]. Since you are going for as streamlined a setup as possible, you will probably not find a ready made household type item that will be just right, but maybe you will? The opening of the bladder compartment should be sealed off[from the inside of the plane] as well. If you make the compartment out of balsa,or 1/64"ply and fuel proof it with epoxy, that will be the lightest way I know of to make a custom fit compartment for a plane like yours. Are you going to maiden this ship with the AME?If you are going to run the AME on bladder with the stock needle, my experience has been that it works, but the course thread needle doesn't give much latitude for adjustment. If you are going to run the GZ, the needle is very fine and it allows very precise adjustment. Can't wait for a flight report, hopefully the storm will pass shortly and leave lots of calm air around for awhile!

xanaphyst

My Feedback: (17)

The wingspan of my delta is 22 inches and it is 16 inches long including ailerons...anyone know where the correct CG should be? I think the plans
may be wrong.

Thanks,
xanaphyst

combatpigg

My Feedback: (3)

I just took a look at 2 deltas that I've designed and the CGs are at 95% of the average chord. Take your root chord plus the tip chord, I'm guessing with yours would work out to 22", next divide by 2, so 11" is the average chord and 10" from the trailing edge of the elevons would be the 95% or so station point. I don't know how I arrived at this method but it works for me when using L.A.R.D. designs to get a working CG. Hopefully someone will chime in with a proven location for you though.

xanaphyst

My Feedback: (17)

OK..after forever and a day here it is !!!! No flight report yet but hopefully early in the week. The changes in version 2.0 are...
Looks like about 10 oz. but not quite sure...need to find scale
1 Used bladder instead of tank
2 AME w/ venturi instead of rc rubberbanded open
3 Smaller NiMh batteries
4 H55's instead of 81's
5 Hatch
6 Vertical fins
7 Downthrust built into firewall
8 THINNER AIRFOIL (believe it or not..it's true)

combatpigg

My Feedback: (3)

That's an amazing job of keeping everything within the confines of the airfoil. Be patient with the needle setting with the bladder, take your time to be sure the engine is happy before throwing it. The initial drip rate should be fast moving drops that are just a few clicks away from a steady stream. I don't prime, just burp the line while spinning with a starter. It is always better to tune from the rich side. Good luck with it! It will be interesting to get this one clocked, it is going to be lightning quick too at 10 ozs, should be capable of mind blowing changes of direction. You must have learned something about the first one to prompt you to put down in the motor?

ptulmer

My Feedback: (5)

You better have great eyesight! What size is that prop?! You might look at an APC or a cut down MAS. If you want speed you'll want maximum pitch. CP oughtta have a good opinion on speed props for the AME.[>:] You two have got me thinking speed now...

combatpigg

My Feedback: (3)

The MAS cut down to 4.25" works well on the AME. If you want to pipe time the AME, I would guess that the APC 4.2-4 is a good match,but this prop needs an engine that can really spin it for it to put out. If you have the airframe to support the speed, keep taking away diameter [of the MAS 4.25-4]. This little delta might even do OK with less than 4" of diameter. If you buy the MAS twin pack, it will cost about a buck to find out.

xanaphyst

My Feedback: (17)

The prop is a 5+3...I'll use it to start because I don't want hyper-speed on the test flights..I have a pretty large selection of small props hanging around to try and also some cut down MAS props. The down thrust is because the original wanted to climb pretty hard before trimming it out. These little buggers are tough when not trimmed!!
I'll be running it blubbering rich for a few flights as the engine isn't broken in yet but I have found these Norvels don't need all that much break in before they run fairly decent,but they do get better with time. I got in late from work today so I don't have a flight report yet..hopefully soon.
CP...I put your resin in some containers and just need to get them boxed and in the mail.
PT...glad to see your thinking of getting in on the speed-wagon !! I'll be getting started on the %75 lil streak soon!!

xanaphyst

combatpigg

My Feedback: (3)

The 5-3 is a good plan, but it's still going to be BALLISTIC! Power/ weight of about 2.5/1[X(]!

mclintock

My Feedback: (3)

dang- I'd have to put a combat ribbon on that thing in order to see it better.. I hope you can get someone to videotape that thing flying!

xanaphyst

My Feedback: (17)

BANG BOOM POW BABY !!!! I finally got a good day in to fly and what a great day it was....The first flight ended in about 1.2 seconds with a nose dive straight in and hairline cracked both R1 ribs..BUT .the bottem sheeting and carbon LE spars were still holding so I decided to give it a go even with the semi-loose firewall. We pressured
up the bladder and fired her off....launch was followed by some hard correction to the right and off she went !!
With the 5+3 it will outrun any plane we're running at the field right now. The bladder fuel system is flawless and I plan to use it as often as possible in all future models..its that good !!! After 4 minutes of knee knocking it shut down and began a decent glide. It touched down 20 feet away from me and I started breathing again !!!
I feel the 5+3 did it's job but it's time to move on to better things....Next installment will be a 4.5+3.5 MAS.
It is not as hard to see as I thought it was going be but I consider today to be the most intense flying moment to date I've ever had....I can't hardly wait to make it faster !!!!!!!

Xanaphyst

combatpigg

My Feedback: (3)

That's a great flight report! Did you follow my rule of thumb guidelines for finding the CG? I'll bet that plane has everybodies' attention front and center when it is show time[X(]!