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Aluminum Tig ? for the pros or whoever

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  • monte55
    started a topic Aluminum Tig ? for the pros or whoever

    Aluminum Tig ? for the pros or whoever

    I'll try to explain without pics..... I have a 6" diameter aluminum disk x .125 thick. I also have a 6" ID x .125 wall aluminum tube. The disk will fit into the
    end of the tube flush with the end. It's a snug fit. I want to tig these together. I also want the weld to be flush. Do I v taper the inside of the tube
    and taper the disk so when they come together there will be a V to fill and then grind flush. This has to be perfect. It will be spinning about 1000 rpm
    What sequence... do I spot, then weld to have it stay true? Explain. This is the gear enclosure for my helicopter project that will hold oil..
    KB hellllllllllllllllllllp!!
    Thanks ..............................Nick

  • Blackbird455
    replied
    Oh Holy crap!!!!! c 1/222 !!! USAALS. UGGH . Well the gallons of Killians at "the Junction" almost made the morning runs by the River bearable.

    I agree with yall though, I have run an AVA on OH-58's and Uh-60's for several years, and I can tell you, that I got a 58 down to no more than .005 IPS , on the lat, vert, hover, etl, 80 k , climb, and 110k, and it still shook like a table dancer. After Hurricane Katrina we caught a garbage bag on a 58 blade and I thought she was going to come apart. Luckily we were at about 10 ft hovering.

    I have seen vibrations do silly stuff, so yeah, get a grab bag of self locking and castellated nuts, and stainless cotter pins. A few cents of hardware can make or break all that hard work. If you can, get an accelerometer to measure vertical and lateral vibs, and try to balance below .020 ips (inches per second).

    Leave a comment:


  • UH60LCHIEF
    replied
    Originally posted by Fishy Jim View Post
    Oh come on, you miss charlie company 1/222.
    too many trips down the autobahn there beep beep! Vroom vroom!

    Leave a comment:


  • turboglenn
    replied
    I've made a few air tanks to hold nitrogen/co2 for the air shifters on both drag bikes and a few rail cars. I just ground the outter edge of teh disk in about 1/2 way at a ~608 angle and then took a porting tool and made a slight taper in the inside edge of the tubing as well. So far they have held 140psi with no issues, i think it will contain your oil easily, just double echeck for pin holes before putting it into service.

    Leave a comment:


  • Fishy Jim
    replied
    Oh come on, you miss charlie company 1/222.

    Leave a comment:


  • UH60LCHIEF
    replied
    those hours were spent in the back manning the 60 or the 134 and conducting slingload ops. I managed a bit of stick time (off the books of course) and I went back to school to become an engineer afterward so I never bothered to test for my A & P though the thought occasionally still crosses my mind. I miss the flying for sure, and the guys (Army aviation is chock full of wonderfully whacko folks), but the Army... Not so much


    Mark

    Keep posting up the pics. I'm curious to see how this turns out.

    Leave a comment:


  • monte55
    replied
    I'm thinking about installing a rubber seal on top of the brass ring that hugs the non rotating shaft so I can have more lube to keep in contact with the gears. The original version of this unit flew quite a bit with totally exposed gears but since has enclosed them. All hardware will be safety wired upon final assembly. This is a heli that will mainly hover in ground effect but will go much higher. There is a direct relationship between ba!!s and height flown.
    The man who flew his flew his about 20-25 feet agl judging by the videos.
    No safety there Have you seen his videos? Pretty cool. Back in the 70s
    I was going to build the Choppy but realized I didn't have the tools, knowledge etc. But, I did read a lot on fully articulating rotor heads and thought "what genius" and what effects and problems. I learned a lot from a Scorpion I bought, rebuilt some but never flew. Sold it and got a Cessna 150
    and got my licence. I love this stuff!!!!!!!!! Did you pilot or ride for 2500 hours? Are you an A&P on helis...................Nick

    Leave a comment:


  • UH60LCHIEF
    replied
    A fully articulating rotor system it is not. There will be no leading, lagging or aerodynamic feathering here. I worked on helo's for eight years, and have over 2500 hours in Blackhawks and you definitely need safeties on that hardware for sure; ESPECIALLY on anything that rotates. You might want to just put a seal on the top of that oil reservoir and then put enough volume in it so the spider gears will contact it when it is at full RPM. You can figure the fluid volume simply by measuring the diameter and height of the tank, measure the distance of the spider gears from the inside diameter of the tank and subtracting the two (remember to add to that distance how much of the spider gear you want to be in contact with the oil. You will need a seal for sure though as those gears will be slinging that oil everywhere regardless. Itís an interesting idea, but having seen firsthand the results of several helo crashes youíll definitely want that insurance policy paid up.

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  • monte55
    replied
    This unit has no collective. Rotors are fixed pitch and can't be changed during flight. Altitude is achieved by rpm. Direction is through weight shift or rotor tilt.
    They will flex some though.
    Last edited by monte55; 09-16-2008, 03:41 PM.

    Leave a comment:


  • Fishy Jim
    replied
    Nick, ALL helicopters vibrate! It's the nature of the beast. The rotor head has so much going on in it, that it wiggles from simple inertia of the parts changing direction (the blades must change pitch independently or you wouldn't be able to steer).

    If I was on a chopper that stopped vibrating, I would bend over and kiss my azz goodbye - cause that would be very, VERY bad.

    A fixed wing aircraft is just losing that new plane stink at 3000hrs, while a helo is about ready for the bone yard.

    Leave a comment:


  • monte55
    replied
    Originally posted by Fishy Jim View Post
    Please tell me the double nut is for mock-up only...

    You need positive retention hardware for this stuff Nick. That means self retaining bolts, castellated nuts with cotter pins, and safety wire. Otherwise I would make sure your life insurance is paid up so the wife and kids have something after you're gone.

    Helo's do one thing better than vertical take offs - they vibrate like you would not believe. Loctite ain't gonna cut it on this one.
    Well Duh!.............yes, this is semi assembly as it will be taken apart and
    reassembled many times before final assembly.
    Nick

    PS.........if the heli vibrates, there will be other problems as well. Everything has to be balanced.

    Leave a comment:


  • Laiky
    replied
    I agree with FJ ( again!) i assumed your just mocking stuff up. If memory serves the book you want to reference (if you don't already know) is the AC 43.13 available for download from the EAA


    http://www.experimental.ch/component...,15/Itemid,41/

    Leave a comment:


  • Fishy Jim
    replied
    Please tell me the double nut is for mock-up only...

    You need positive retention hardware for this stuff Nick. That means self retaining bolts, castellated nuts with cotter pins, and safety wire. Otherwise I would make sure your life insurance is paid up so the wife and kids have something after you're gone.

    Helo's do one thing better than vertical take offs - they vibrate like you would not believe. Loctite ain't gonna cut it on this one.

    Leave a comment:


  • monte55
    replied
    Gear Housing Pic. part 2

    Here are two more pics. Notice the room above the thin aluminum slinger. I can also insert a foam seal just in case..to keep things cleaner.

    Nick
    Attached Files

    Leave a comment:


  • monte55
    replied
    Gear Housing pictures

    Ok...............here's the housing I came up with. It's a 6" diameter and you can see the gears inside. I found a brass base that I cut and fit to the ID of the can. The outer width of the the brass round should keep the oil in place. The
    ID of the brass is sloped down to allow drainage back down. Just above the brass ring is the thin aluminum slinger. This should sling any fluid that may come out the middle to the can walls again. When I come up with direction
    of rotation of the rotor(depending on engine and drive) I may cut the brass
    to include downward deflectors or add them. The holes on the side will have plugs. They are necessary to remove the bolt from the side gears when the can is in place.
    Attached Files

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