Notices
Scratch Building, Aircraft Design, 3D/CAD If you are starting/building a project from scratch or want to discuss design, CAD or even share 3D design images this is the place. Q&A's.

good for something...

Old 12-18-2009, 09:02 AM
  #1  
crash bandicoute
Senior Member
Thread Starter
 
Join Date: Aug 2009
Location: McChord AFB / Orting, WA
Posts: 643
Likes: 0
Received 0 Likes on 0 Posts
Default good for something...

im getting ready to start my first scratch build and was trying to think of a way to keep all the notches in the ribs and bulkheads the same size for my stringers and sparsinstead of having some a little too loose and too tight. you can get a small piece of brass square "tubing"in the size you need for spars andsub-sparsand sharpen the edges and use it for a type of punch, if the wood you're using isn't too thick,lining the edge of it up withthe edge of the piece of wood after you get it cut out. if it is too thick to go through, at least you get a marking of where to cut it instead of guessing.even for bulkheads orformersor WHATEVER...the link to it...http://www3.towerhobbies.com/cgi-bin...?&I=LXR847&P=0. and it's in different sizes.
Old 12-18-2009, 09:32 AM
  #2  
kdc
 
Join Date: Nov 2002
Location: Shenfield, UNITED KINGDOM
Posts: 685
Likes: 0
Received 0 Likes on 0 Posts
Default RE: good for something...

Good idea. The tube ( round or square ) is of course sharpened on the inside.
There was a whole 5 page article on making proper punches from silver steel by Alec Whittaker in the English magazine RCME January 2009.
Lots of info including the important point of having a soft pine wood underneath as an anvil. Also could be punched halfway and the wood turned over to complete the cut to cut cleanly. Some people wet the wood to soften before punching in kit production it seems.
Old 12-18-2009, 01:33 PM
  #3  
ARillos
 
ARillos's Avatar
 
Join Date: Mar 2004
Location: Overland Park, KS
Posts: 105
Likes: 0
Received 0 Likes on 0 Posts
Default RE: good for something...

For ribs, I use the sandwich method. Build two rib templates from 1/16 or 1/8 hard plywood, drill two holes and use two long 3/16 bolts for clamping the ribs. Cut the rectangles for the ribs (half wing at a time) drill the ribs using the template, bolt them together and sand them to match the template. For any additional notch use the X-Acto saw and or no.11 traditional blade. Good luck! Alex.
Old 12-18-2009, 04:25 PM
  #4  
yel914
 
yel914's Avatar
 
Join Date: May 2005
Location: SALT LAKE CITY, UT
Posts: 742
Likes: 0
Received 0 Likes on 0 Posts
Default RE: good for something...

I've also cut out those notches with short lengths of fine toothed hacksaw blades, stacked together for the proper thickness and taped on the ends. A few passes makes a good fitting notch.
Old 12-18-2009, 08:01 PM
  #5  
Edwin
My Feedback: (2)
 
Join Date: Feb 2002
Location: Leander, TX
Posts: 6,204
Likes: 0
Received 0 Likes on 0 Posts
Default RE: good for something...

I use a hardwood sanding block the width of spar with some 80 grit stick on sand paper. It makes the slot the exact width.
Edwin
Old 12-18-2009, 08:07 PM
  #6  
Jim_Purcha
My Feedback: (8)
 
Join Date: Sep 2003
Posts: 1,915
Likes: 0
Received 1 Like on 1 Post
Default RE: good for something...

I've done this too. Use the same size of spar with sand paper. Works great. Used it on tapered spars.

Jim
ORIGINAL: Edwin

I use a hardwood sanding block the width of spar with some 80 grit stick on sand paper. It makes the slot the exact width.
Edwin
Attached Thumbnails Click image for larger version

Name:	wu61624.jpg
Views:	16
Size:	56.7 KB
ID:	1337220  
Old 12-20-2009, 08:05 PM
  #7  
Laird SS
Senior Member
 
Join Date: Apr 2005
Location: Peoria, AZ
Posts: 603
Likes: 0
Received 0 Likes on 0 Posts
Default RE: good for something...

Jim's method of sanding the slots is the way we did it back in the days of rubber powered models like those from Cleveland Model Supply. It worked well. Also, as Jim said, it works well on tapered wings where the slots may not be perpendicular to the sides of the ribs.

Old 12-20-2009, 10:06 PM
  #8  
BMatthews
 
BMatthews's Avatar
 
Join Date: Oct 2002
Location: Chilliwack, BC, CANADA
Posts: 12,355
Likes: 0
Received 10 Likes on 8 Posts
Default RE: good for something...

You've got the right idea but the wrong tool with the brass tubing. At least it's the wrong tool unless you want to put the spars into the middle of the ribs. The brass tubing will tend to crush the wood and produce oversize holes unless it's extremly sharp. I cut holes with round tubing that I sharpen but in that case I can twist the tubing to aid the cutting. But with the retangular or square tubing you're stuck with a pure push.

For normal three sided notches the methods mentioned above work out far better. For myself I prefer to make my own spar "rasps" by gluing together fine tooth hacksaw blades. The final size being achieved by stoning off a little of the tooth set to get a light but firm push fit for the spar wood. That makes for a good glue joint. The less glue the better.

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


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.