Cutting off Inner C's: Need Advice

Polishing up a new D30 HP for 35's. I will be sleeving it with 3" OD x .250" wall DOM then trussing. I have cut off all the brackets and am now trying to get the inner "C's" off. I have cut off all the weld fillet. I have cut down into the axle tube about 1/3 of the tube thickness to get at the weld penetration. I have back cut the C's about 1/8 of an inch to make sure all the weld is off of the C's.

Wailing on it with sledge hammer has no effect. Tried to drive it off (hitting along axis of the tube), tried to twist the C's by hitting them on the side to twist them off the axle. No joy.

I am not comfortable cutting any deeper into the tube. Lots of meat on back side of the C's beneath where the weld filet use to be so I can cut deeper into the C if need be. There is no weld on the outboard side of the C between the C and tube.

Do I need to heat it up with an oxy-acetlene rose bud (its pressed on at the factory then welded), should I keep back cutting the C or is there something I am missing here?

Picture to follow.







John

We've done quite a few of these, mostly 44's and 60's, never a fun job. Pics are always deceiving but it looks like you need to grind more into the C, use a thin cutting disc and keep it about 20 degrees up from the axle tube so you're cutting into the C more. I've never touched at torch to an outer, just a 4lb hand smacker. You'll see that weld crack and work it around.

Good luck!

Thanks for the reply. I will continue to cut into the C. Lots of meat, unlike the tube.

BTW: I have run a set of your rails for 5 years now and absolutely love them. Great product at a fantastic price.

John

When you grind far enough into the C to get through the weld, a thin rust line will appear in the grind area. Don't be too surprised if you have to grind back at about a 30 deg. angle on the C to get through the weld. They get huge penetration at the factory. Once you get the C off the tube, don't grind the tube down any more or work on the inside of the C. Even just to "clean it up." Heat the C , and leave the housing outside overnight to cool down the tube before you smack it back on.

Now's also the time to adjust pinion angle/castor relationship if you need to. 'Given it any thought?

tbburg,

Thank you for the advice. I will try to keep the angle at 20-30 degrees , perhaps closer to 30 to cut deeper into the C. I will be welding up any cuts into the tube, but the fewer and the shallower the better. I am surprised at the penetration into the C. Cant wait to see the rust line.

I have given some thought to caster and pinion angle, this is particularly important since its a D30HP and I wont have lockout hubs. I will be rotating the C's to set the caster and pinion angel to a more favorable range. I am building for a low COG at 4.5" to 5" lift. I was planning on setting caster at 5-6 degrees with the pinion up from 11-12 degrees. I When I get to that point I will put the C's on, set the XJ at ride height and place the axle underneath to line everything up before tacking it in place. I may set Chassis at a ride height of 5" when I do the tacking so the set will be close to correct for anything from 4.5 to 6" even though I dont plan on going up to 6.

John

AJsArmor said:

We've done quite a few of these, mostly 44's and 60's, never a fun job. Pics are always deceiving but it looks like you need to grind more into the C, use a thin cutting disc and keep it about 20 degrees up from the axle tube so you're cutting into the C more. I've never touched at torch to an outer, just a 4lb hand smacker. You'll see that weld crack and work it around.

Good luck!

Click to expand...

Exactly what AJ said.
Billy

Sounds like you're well down the road to knuckle removal, which makes wonder why......with all the other options. Rotation of the knuckle doesn't require removal.

Here's another idea for beefing up the housing/tubes....Mt Logan Offroad has done this on several rigs.

http://www.rockymountainextreme.com/showthread.php?t=60824

XJEEPER said:

Sounds like you're well down the road to knuckle removal, which makes wonder why......with all the other options. Rotation of the knuckle doesn't require removal.

Here's another idea for beefing up the housing/tubes....Mt Logan Offroad has done this on several rigs.

http://www.rockymountainextreme.com/showthread.php?t=60824

Click to expand...

It says you need to register to view those pictures.

XJEEPER said:

Sounds like you're well down the road to knuckle removal, which makes wonder why......with all the other options. Rotation of the knuckle doesn't require removal.

Here's another idea for beefing up the housing/tubes....Mt Logan Offroad has done this on several rigs.

http://www.rockymountainextreme.com/showthread.php?t=60824

http://www.rockymountainextreme.com/attachment.php?attachmentid=40334&d=1229371503

Click to expand...

It's tough to get the .250" wall DOM tubing over the knuckles

nosigma said:

I will be sleeving it with 3" OD x .250" wall DOM then trussing....

Click to expand...

EDIT: OIC - The link illustrates sleeving the inside of the tube.

Billy

JeepFreak21 said:

EDIT: OIC - The link illustrates sleeving the inside of the tube.

Billy

Click to expand...

Regarding the "inner-sleeve":

Mt. Logan Off-Road said:

We do a bunch of welding on this conversion. We have a piece of dom turned down to fit inside the stock axle. The new tube has a .250" wall. We weld the full radius of the opening at the inner c, we drill a bunch of holes through out the axle tube and weld the outer tube to the inner tube. We drill and weld 4 holes right where the tube goes into the cast housing, then weld the cast housing to the outer tube, and gusset the inner c.

Click to expand...

Pretty cool idea.
Billy

If you're going through all of that work you mind as well have upgraded to a narrow 44 up front. Or something to that effect.

I wonder where you got this idea nosigma?



I broke 3 4 pound hammers before I picked up a 12 pound sledge. I had two friends hold the housing while I took my swings, I started to see the cracke show after 5 or 6 swings.

You need to shave the entire housing down really smooth in order to get the sleeve over it. If you haven't taken metal off of every bit of the tube, you won't get it all the way on.

Begster said:

It says you need to register to view those pictures.

Click to expand...

x2, anybody have them saved? Don't need any more forums to check.
The d30 I have has a inner sleeve of .25" wall 4130 tubing, I'll snap some pics when I get better and head back to the shop, the only problem is the id of the d30 is not a readily available tubing size so the od of the tube you are going to shove in there has to be turned down slightly.

How hard is it to get the sleeve over the tubes once cleaned? Does it just slide over, do you tap it on with a BFH or do you press it on with a press?

We took two grown men (myself and a friend), lifted the housing (with the sleeve pointing to the ground) as high as we could, jumped up into the air and slammed the tube into the sleeve with our combined body weight on it.

It took about an hour of that. We had to cut the bottom 1" of the sleeve off because it was mushroomed, and use some spare tube to drive it the last bit.

Whats amazing is that we didn't bend it in the process.

Why I'm asking is that if it's a relatively tight fit and you get it on some way and then discover there's one bit you didn't shave enough, you probably won't get off again!

Put the sleeve in the oven at 450 for a half hour and pack the housing in ice for about an 4 hours. Take some welding gloves to handle the parts and beat them together as quickly as possible before the temps equalize.

Thank you again AJ & tbburg.

I finally hit rust. The total depth into the C was over 3/8 of an inch and very close 1/2 inch in some spots. No point in even bothering with cutting off the factory weld. I will probably try to use the factory weld as a "tool guide" and cut down 20-30 degrees from there to give about the right depth into the C. The back of the C looks more like a deep cone now!

Here are some pics for reference to anyone who is going to do this for the first time.

If you look carefully in the first pic you will see a very thin rust colored curved line. Thats the axle-C joint just like promised. What joy to finally see that!



In the second picture you can see how deep the cut was and can see the same rust colored line at the top (a bit wider) and the one from the first picture appears a bit out of focus on the side, still very thin.



The final picture gives you some sense of depth, just under a 1/4" has been cut off the inside face of the C with the depth to the "rust line" marking the axle tube inside the weld penetration another 1/4".



Hopefully it will come loose with just "persuasion" and light grinding tomorrow. It didnt move much with several dozen hits after the rust line appeared all the way around.

John

After a few minutes more of very judicious cutting, a lot of hammering the C began to move. A couple good soakings with PB, and the next day after a lot more hammering its off.

Note the depth of the cuts into the axle tube. I will be welding these up and grinding them smooth.



I am looking for some experienced advice (welders & axle builders out there), should welding it up be OK or should I worry about making the axle more brittle and breaking at this location? The 3" OD tubing sleeve will not cover this area but the welds that hold the inner C and the tube in place will. I plan on using a MIG welder to do the filling work.

John

Make a fixture that will allow you to rotate the housing around the shaft center. ('Pair of jack stands with deep "V" notches will work) Have a friend slowly rotate the housing while you fill weld that groove. You stay on top and let him move the housing around so you are always welding down. When you finish your pass, cover the tube(welding blanket/asbestos cloth would be ideal) and let it cool down slowly. The slower the better. DO NOT quench the tube to cool it down, or even blow cool air on it. Quickly cooling the metal will leave it brittle, and it will be prone to cracking right at the edge of the weld zone.

Look at some of the pics. on Currie's web sight. They add a gusset to the bottom of the "C" that runs down the tube about 2". You should definitely add something like that.

When you cut the other "C" off, keep the grinding wheel parallel to the tube, and only cut into the weld on the "C". If you're careful, you can cut the weld out without marking the tube up at all.