Giant Scale Aircraft - 3D & Aerobatic Discuss all your 3D & Aerobatic giant scale airplanes right here!

how to cut aluminum??

Reply
Old 11-30-2012, 06:59 PM
  #1
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default how to cut aluminum??

any advice?
i am trying to lighten this backplate. keeping in mind, that when i am done, i will balance it.
it is 5" spinner
this is what i got so far and
i have decreased it by 1 and 1/8 ounce.
i have used a router aluminum bit X 2 (35 dollars)
and a 1 inch drill (30 dollars) did not work.
i could have bought the Tru turn spinner by now, but i am hard headed, so i am making a project out of it.
trying to figure out what else i can use to finish this off??
orthobird is offline  
Reply With Quote
Old 11-30-2012, 07:53 PM
  #2
sensei
 
sensei's Avatar
 
Join Date: Jul 2002
Location: SAN ANTONIO, TX
Posts: 2,630
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

Forget the router, it turns too fast use a drill press and get a UNI-Bit or piloted counter bores to get the job done at slower speeds. Just about any aircraft sheet metal mechanic can show you the way and will have these tools in his tool box if you know any.

Bob
sensei is offline  
Reply With Quote
Old 11-30-2012, 08:32 PM
  #3
hugger-4641
 
hugger-4641's Avatar
 
Join Date: Oct 2008
Location: McKenzie, TN
Posts: 1,875
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

Was there a pic to go with your post? Are you just trying to drill holes in it to lighten it up, or are you trying to mill down the thickness?
hugger-4641 is offline  
Reply With Quote
Old 11-30-2012, 08:44 PM
  #4
sensei
 
sensei's Avatar
 
Join Date: Jul 2002
Location: SAN ANTONIO, TX
Posts: 2,630
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

OK I just saw the pics on another sight; so from where you are at to this point you are going to need a compressor, die grinder with a 1/4" collet, and 1/4" shanked fluted metal cutting bits to finish the job. You can get everything you need at very reasonable prices from Harbor Freight, just take your time and place it on the balancer many times as you go.

Bob
sensei is offline  
Reply With Quote
Old 12-01-2012, 04:38 AM
  #5
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

i am unable to post pictures on this site,  anyone have any advice.
orthobird is offline  
Reply With Quote
Old 12-01-2012, 05:21 AM
  #6
Tony Hallo
 
Join Date: Jan 2003
Location: Springdale, PA
Posts: 1,535
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

At this rate you are doing a better job lightening your wallet than the back plate. You might want to consider buying a new lighten version! But if you are having fun than go for it.
Tony Hallo is offline  
Reply With Quote
Old 12-01-2012, 11:47 AM
  #7
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

wow, i got the backplate down to 2 1/4 ounces.

it originally weighed 5 1/8 ounces.
orthobird is offline  
Reply With Quote
Old 12-01-2012, 12:24 PM
  #8
Yank II
 
Join Date: Jan 2007
Location: Salome, AZ
Posts: 125
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

,
Yank II is offline  
Reply With Quote
Old 12-01-2012, 03:48 PM
  #9
Darryl Usher
 
Join Date: May 2002
Location: Cornelius, OR
Posts: 624
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

When you lighten the back plate you will need a front support for the spinner.
Darryl
Darryl Usher is offline  
Reply With Quote
Old 12-01-2012, 06:28 PM
  #10
sensei
 
sensei's Avatar
 
Join Date: Jul 2002
Location: SAN ANTONIO, TX
Posts: 2,630
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

I read that you decided not to use your modified backplate, thats really OK because you still learned from this experience and I am sure you will apply it later down the road.

Bob
sensei is offline  
Reply With Quote
Old 12-01-2012, 06:40 PM
  #11
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

i have decided i will not be using this.  i will buy a new one. thank you all for comments.
orthobird is offline  
Reply With Quote
Old 12-01-2012, 06:42 PM
  #12
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

that's right bob,
i learned so much
it was fun, and it was an exercise in using high speed routers.
orthobird is offline  
Reply With Quote
Old 12-02-2012, 06:43 AM
  #13
ahicks
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,516
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

And sweeping up alum. shavings?
ahicks is offline  
Reply With Quote
Old 12-02-2012, 05:40 PM
  #14
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

oh yeah, and one impaled me under my eye, even though  i was wearing eye protection.  looks like i got some swelling there right now.  i press deep and there is no pain, so i do not believe there is any metal left in there.
orthobird is offline  
Reply With Quote
Old 12-04-2012, 02:14 PM
  #15
nitro wing
 
Join Date: Sep 2003
Location: surrey, BC, CANADA
Posts: 3,775
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

5 inch spinner, must be a big plane, shaving 2 ounces on the backplate wont to anything for CG changes, if that is why you tried to lighten it.
Take care of the eye, metal fragments can be nasty.
nitro wing is offline  
Reply With Quote
Old 12-11-2012, 03:30 AM
  #16
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

Hi Nitro, you would not believe it, but the balance of plane was within ounces. but it turned out plane was tail heavy, so i re-ordered the backplate and spinner.

Quote:
ORIGINAL: nitro wing

5 inch spinner, must be a big plane, shaving 2 ounces on the backplate wont to anything for CG changes, if that is why you tried to lighten it.
Take care of the eye, metal fragments can be nasty.
Attached Thumbnails
Click image for larger version

Name:	Bz78377.jpg
Views:	6
Size:	110.2 KB
ID:	1828811   Click image for larger version

Name:	Fa86157.jpg
Views:	6
Size:	71.3 KB
ID:	1828812  
orthobird is offline  
Reply With Quote
Old 12-11-2012, 04:12 AM
  #17
orthobird
Thread Starter
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 726
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: how to cut aluminum??

i put in 4 servos for the elevators, 2 on each stab half.  each servo has 500 ou/torque/in
each servo weighs 2 ounces.
the two extra servos is 4 ounces
but at the nose, it is equivalent to 8 ounces needed to counterbalance it.  i did not remove the two extra servos, instead, i undid all my canopy work, and removed the pilot and the instrument panel, and then i perforated the electronics tray.  by doing so, i removed over 1 pound off the plane.
orthobird is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 08:14 AM.