Straightening a rear end housing

Jump to: navigation, search
m (Reverted edits by 99.172.180.123 (Talk) to last revision by Jon)
(Minor clean up; format.)
Line 1: Line 1:
 
{{youcanedit}}
 
{{youcanedit}}
 +
==Introduction==
 
Here's how to make a fixture and rack for straightening a rear end housing.
 
Here's how to make a fixture and rack for straightening a rear end housing.
  
 
==Building a straightening table==
 
==Building a straightening table==
The straightening fixture pictured below is an old gas cylinder cart, bought at a garage sale and the top cut off.  A 6" X 6" I-beam was then welded to the cart. You don't need a cart, any sturdy legs will do. This cart just happened to be handy and had nice wheels so we could wheel it around the shop.
+
The straightening fixture pictured below is an old compressed gas cylinder cart, bought at a garage sale awith its top cut off.  A 6" X 6" I-beam was then welded to the cart. You don't need a cart, any table with sturdy legs will do. This cart just happened to be handy and had nice wheels so we could wheel it around the shop.
 
[[Image:Axle_straightening_table.jpg|frame|none|A gas cylinder cart, converted for straightening rear end housings.]]
 
[[Image:Axle_straightening_table.jpg|frame|none|A gas cylinder cart, converted for straightening rear end housings.]]
  
To prevent any mishaps involving slippage and gravity, common jackstands are cut up to wrap the leg of the I-beam. The bottoms were notched and a slice made at each corner to get the stands fitted to the I beam.[[Image:Modified_jackstands.jpg|frame|none|Basic inexpensive jackstands are modified to wrap the I-beam for stability.]]
+
To prevent any mishaps involving slippage and gravity, common jackstands are cut up to wrap the leg of the I-beam. The bottoms were notched and a slice made at each corner to get the stands fitted to the I-beam.[[Image:Modified_jackstands.jpg|frame|none|Basic inexpensive jackstands are modified to wrap the I-beam for stability.]]
  
A straight bar is necessary. This hardened and chrome-plated bar is about five feet long, and 1.5" in diameter. It's available from McMaster-Carr for about $115.00. Alternatively, an old length of scrap steel shafting can be used. V-blocks and a dial indicator can be used to verify that a used bar is straight. Smooth, round and straight is best. You could use 1" round bar but the accuracy will suffer. One of the manufacturers that sells these alignment fixtures uses 1 11/16" bar. Bigger than 1 3/4" and the bar will be too big to handle.
+
A straight bar is necessary. This hardened and chrome-plated bar is about five feet long, and 1.5" in diameter. It's available from McMaster-Carr for about $115.00. Alternatively, an old length of scrap steel shafting can be used. V-blocks and a dial indicator can be used to verify that a used bar is straight. Smooth, round and straight is best. You could use 1" round bar but the accuracy will suffer. One of the manufacturers that sells these alignment fixtures uses 1-11/16" bar. Bigger than 1-3/4" and the bar will begin to become too unwieldy to handle.
 
[[Image:Hardened_bar.jpg|frame|none|A hardened and chrome plated steel bar.]]
 
[[Image:Hardened_bar.jpg|frame|none|A hardened and chrome plated steel bar.]]
  
Line 24: Line 25:
 
[[Image:PICT0040.JPG|frame|none|9" Ford center section with inserts and bar.]]
 
[[Image:PICT0040.JPG|frame|none|9" Ford center section with inserts and bar.]]
  
Another way to determine if the housing is straight is to machine the inserts for the diff center with a small center hole, clamp these in and install centre in housing.Then usng a sheet of paper with a small hole held at the bearing end site through and line up with two holes that are in the center then run your finger around the tube end marking the paper. find the center of you mark and this will show you how far your diff is out by comparing the hole in the paper to the center.
+
Another way to determine if the housing is straight is to machine the inserts for the diff center with a small center hole, clamp these in and install centre in housing.Then using a sheet of paper with a small hole held at the bearing end site through and line up with two holes that are in the center then run your finger around the tube end marking the paper. find the center of you mark and this will show you how far your diff is out by comparing the hole in the paper to the center.
  
 
==Measuring==
 
==Measuring==
Line 34: Line 35:
  
 
==Heating and bending==
 
==Heating and bending==
Next, rig a chain at the point of bend and put a 12-ton bottle jack under the end of the axle. To prevent bending the center casing, attach the rear cover. You can try to bend the axle tube at this point, without heat. If you want to bend the tube in this way, push the tube approximately 5 times the amount you want it bent. In other words, if your alignment is off by .030" , you need to push the end of the tube about .150" or more to overcome springback. If your axle housing end is off by more than .100" from the alignment jig, you will probably need some heat.
+
Next, rig a chain at the point of bend and put a 12-ton bottle jack under the end of the axle. To prevent bending the center casing, attach the rear cover. You can try to bend the axle tube at this point, without heat. If you want to bend the tube in this way, push the tube approximately 5 times the amount you want it bent. In other words, if your alignment is off by .030" , you need to push the end of the tube about .150" or more to overcome spring-back. If your axle housing end is off by more than .100" from the alignment jig, you will probably need some heat.
 
[[Image:Bottle_jack_and_chain.jpg|frame|none|A bottle jack and chain are used for bending.]]
 
[[Image:Bottle_jack_and_chain.jpg|frame|none|A bottle jack and chain are used for bending.]]
  

Revision as of 18:23, 31 March 2012

Personal tools
Namespaces
Variants
Actions
Navigation
Categories
Toolbox