The Biplane Forum > Biplane Builder's Forums > Pitts > Pitts Fuselage & Empennage > Restore,Busting rust.
Reply
 
Thread Tools Display Modes
Old 08-09-2017, 03:02 AM   #1
Smarcoux
Registered Users
 
Smarcoux's Avatar
 
Join Date: Apr 2015
Location: Central Mass.
Posts: 64
Liked 7 Times on 7 Posts
Likes Given: 50

Default Restore,Busting rust.

To all you guys that do restores. I have tail pieces that need rust busting. I have walnut and black beauty for blasting. I understand black beauty should not be used but I have fine grit walnut witch I don't think will do the job.Should I use plumbers mesh?


IMG_0212.jpg   IMG_0213.jpg  
__________________
I'll try and keep skydiving and flying two separate sports.
Smarcoux is offline  
 
Reply With Quote
Old 08-09-2017, 03:36 AM   #2
TFF1
Registered Users
 
Join Date: Apr 2010
Location: Memphis,TN
Posts: 2,516
Liked 398 Times on 306 Posts

Default

Your not going to like it. I say glass beads. That is no light cleaning job. You want to know how deep the pits are and if you need to replace metal or not. That is not a conservation job. It is evaluation if it should be scrapped or not. Airtractor uses the black beauty on new aircraft, but they have thick metal that the paint really needs to stick to.


TFF1 is offline  
 
Reply With Quote
Old 08-09-2017, 03:39 AM   #3
TFF1
Registered Users
 
Join Date: Apr 2010
Location: Memphis,TN
Posts: 2,516
Liked 398 Times on 306 Posts

Default

I think it is 10% of metal thickness where you have to consider the pits too deep.
TFF1 is offline  
 
Reply With Quote
Old 08-09-2017, 03:49 AM   #4
Lotahp1
Registered Users
 
Lotahp1's Avatar
 
Join Date: May 2012
Posts: 3,225
Liked 614 Times on 443 Posts

Default

Aluminum oxide is what the place I take my fuselages etc to uses. A&A Dry Strip. Was that under the fabric or just built and left outside for a long time? There will be rust INSIDE the rear spar as I see it's not sealed (the horizontal slides onto the carry through structure/spar so it's not suppose to be sealed).
Lotahp1 is online now  
 
Reply With Quote
Old 08-09-2017, 03:49 AM   #5
wzm
Registered Users
 
Join Date: Sep 2016
Posts: 26
Liked 20 Times on 5 Posts
Likes Given: 4

Default

I'd rub it down by hand with some red scotch brite and see what's left. If it starts to dissolve, or you see heavy pitting, stop and use it as a template instead. It isn't too hard to duplicate the rudder and elevator, and that's looking pretty far gone.
wzm is online now  
 
Reply With Quote
Old 08-09-2017, 04:03 AM   #6
Smarcoux
Registered Users
 
Smarcoux's Avatar
 
Join Date: Apr 2015
Location: Central Mass.
Posts: 64
Liked 7 Times on 7 Posts
Likes Given: 50

Default

These are the parts that did not get treated with primer or paint. They where never covered.
I feel like it would only take a little more time and money to do them over. (build new ones.)
The digital pics does tend to exaggerate the condition. Best guess it was made in the 70'S and waited for the rest of the build and assembly.
__________________
I'll try and keep skydiving and flying two separate sports.

Last edited by Smarcoux; 08-09-2017 at 04:26 AM.
Smarcoux is offline  
 
Reply With Quote
Old 08-09-2017, 11:44 AM   #7
EAABipe40FF
Registered Users
BiP_SUPPORTER.png
 
EAABipe40FF's Avatar
 
Join Date: May 2009
Location: Springfield, WV
Posts: 3,937
Liked 706 Times on 561 Posts
Likes Given: 461

Default

Yea, they may look worse than they really are but my first reaction was to scrap them.
__________________
Finished Spezio Tu-holer N92JM(Oct. 2011), AcroDuster 2- SA750 N22JM, first flight 12-14-15
2Cor5:17
EAABipe40FF is offline  
 
Reply With Quote
Old 08-09-2017, 12:50 PM   #8
Lotahp1
Registered Users
 
Lotahp1's Avatar
 
Join Date: May 2012
Posts: 3,225
Liked 614 Times on 443 Posts

Default

May just be surface. But like I said, the tube was left open...I'd want the rust out of the inside of the tube. Maybe some navel jelly? (I think that's what it's called?) even if the outside is ok after clean up...you don't want it rusting away from the inside out.
Lotahp1 is online now  
 
Reply With Quote
Old 08-09-2017, 01:03 PM   #9
Knight Twister
Senior Member
 
Join Date: Jan 2008
Location: My mom\'s basement in flyover country
Posts: 2,245
Liked 809 Times on 530 Posts
Likes Given: 68

Default

From looking at the pics light media isn't going to cut it. I've taken lightweight parts that rusty to the regular sandblast place and told them to be careful and not over do it. The spar and leading edge may be rusted a few inches in. A small dingle berry hone used for automotive wheel cylinders may salvage the insides. Worth trying to save. With pre bent leading edges and ribs there is still 6 to 8 hours of time to build new ones. They may end up being wall ornaments.
Knight Twister is offline  
 
Reply With Quote
Old 08-09-2017, 01:40 PM   #10
pigpenracing
BiP_SUPPORTER.png
 
pigpenracing's Avatar
 
Join Date: Dec 2009
Location: Brenham Texas
Posts: 1,923
Liked 392 Times on 244 Posts
Likes Given: 398

Default

That looks like a part off the Titanic.
pigpenracing is offline  
2
People Like This 
Reply With Quote
Old 08-09-2017, 01:56 PM   #11
EAABipe40FF
Registered Users
BiP_SUPPORTER.png
 
EAABipe40FF's Avatar
 
Join Date: May 2009
Location: Springfield, WV
Posts: 3,937
Liked 706 Times on 561 Posts
Likes Given: 461

Default

What's worse is when you take the fabric off and that's what you find.
__________________
Finished Spezio Tu-holer N92JM(Oct. 2011), AcroDuster 2- SA750 N22JM, first flight 12-14-15
2Cor5:17
EAABipe40FF is offline  
 
Reply With Quote
Old 08-10-2017, 01:11 PM   #12
mjk51
Member
 
mjk51's Avatar
 
Join Date: Sep 2006
Location: N. W. Ohio, United States
Posts: 119
Liked 23 Times on 18 Posts

Default

I would not attempt a restore on parts in that condition. You will never be confident in their integrity.
mjk51 is offline  
 
Reply With Quote
Old 08-12-2017, 08:34 PM   #13
Smarcoux
Registered Users
 
Smarcoux's Avatar
 
Join Date: Apr 2015
Location: Central Mass.
Posts: 64
Liked 7 Times on 7 Posts
Likes Given: 50

Default

After attempting to knock off the rust with different media, I can say with confidence "Wall hangers they are!"
AO 180 worked the best but they are to far gone.......not sure if they were acceptable even if they were rust free.
The whole confidence thing is an excellent point.

I know it has been mentioned before but, where is a good supplier for 4130 on the east coast?
IMG_0215.jpg   IMG_0217.jpg  
__________________
I'll try and keep skydiving and flying two separate sports.
Smarcoux is offline  
 
Reply With Quote
Old 08-13-2017, 02:02 AM   #14
lakeracer69
Registered Users
 
Join Date: Nov 2016
Posts: 42
Liked 6 Times on 4 Posts
Likes Given: 2

Default

Quote:
Originally Posted by Smarcoux View Post
After attempting to knock off the rust with different media, I can say with confidence "Wall hangers they are!"
AO 180 worked the best but they are to far gone.......not sure if they were acceptable even if they were rust free.
The whole confidence thing is an excellent point.

I know it has been mentioned before but, where is a good supplier for 4130 on the east coast?
I would try TW metals in Agawam, Mass. I live in NH and think that's where I'm getting any additional tubing for my project. Where are you in Mass?
lakeracer69 is offline  
 
Reply With Quote
Old 08-13-2017, 02:30 AM   #15
Smarcoux
Registered Users
 
Smarcoux's Avatar
 
Join Date: Apr 2015
Location: Central Mass.
Posts: 64
Liked 7 Times on 7 Posts
Likes Given: 50

Default

Hubbardston about 5deg and 6 miles off runway 18 from Gardner airport.

Thanks I'll look into it. At least I have a decent templet.
__________________
I'll try and keep skydiving and flying two separate sports.
Smarcoux is offline  
 
Reply With Quote
Old 08-13-2017, 08:17 PM   #16
jrs14855
Premium Member
 
Join Date: Feb 2011
Location: Lake Havasu City AZ
Posts: 1,366
Liked 239 Times on 185 Posts

Default Stabilizer

The inboard stabilizer rib is missing two diagonal brace channels that prevent the fabric from bending the rib.
Problem building these is that the leading edge tube is difficult to bend properly. You may want to see if Aviat or Steen will sell prebent tubes.
__________________
jim stanton
jrs14855 is offline  
 
Reply With Quote
Old 08-14-2017, 12:54 AM   #17
Smarcoux
Registered Users
 
Smarcoux's Avatar
 
Join Date: Apr 2015
Location: Central Mass.
Posts: 64
Liked 7 Times on 7 Posts
Likes Given: 50

Default

Hu prebent, it never occurred to me.

The age of this project was started before the stiffeners for the stabilizers were drawn in.

I will try my hand with some scrap first. If I'm not happy then I will look into it.
__________________
I'll try and keep skydiving and flying two separate sports.
Smarcoux is offline  
 
Reply With Quote
Old 08-14-2017, 06:44 PM   #18
jstreat
 
jstreat's Avatar
 
Join Date: Feb 2011
Location: Kelly Airpark, Elbert, CO
Posts: 577
Liked 145 Times on 85 Posts

Default

junk


__________________
JSTreat
jstreat is offline  
 
Reply With Quote
Reply


Thread Tools
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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Rust under new fabric Dennis Flamini Acrosport 5 09-15-2014 03:54 PM
Rust on fuselage jetsareforkids Waco & Hatz 8 12-01-2013 03:07 AM
rust removal bonanzadrv Skybolt Fuselage & Empennage 0 07-16-2009 05:49 PM
surface rust!!! bonanzadrv Skybolt Fuselage & Empennage 9 01-31-2008 05:05 PM
Rust prevention scottly Hangar Talk 3 11-12-2007 12:48 AM