Martack

[weak-link]

Searched and just found mentions of it. But I'm looking for a specific length to place the weld so I know I'm close.

The more i think about it, it should be the same as the mini trucks...right?


stolen from pbb

Martack - See 'Birf Stuff' above for more info on this....

The easiest way to find the correct location for a Martack is to put tape on the spines of the axle shaft and insert the axle into the housing while watching the seal location. And keep moving the tape until you found the correct position.
http://www.pirate4x4.com/forum/attac...postid=1537731

Also note that after tacking the splines you wil have to carefully grind them doen flush so the axle will slip into the spider gears/locker all the way to the tack. Another way is to grease the splines but for me that has never worked as good as using tape. You want to place the tack weld so the axle can not slide into the diff to causing the seal to leak diff fluid into your knuckle. This is also used with aftermarket Birfs so you can remove the outer most clip to add in removal of the axle from the birf n the case of trail breakage.

Another think tha tis important to note is that you SHOULD measure this distance on you axle and not following any one elses dimensions becasue there are too many variables to only use on tack weld location for all set-ups.

Quote:
Originally Posted by 4RnrRick
Here a sketch that I did quickly to show you what my understanding of what a Martack does.

The top version (factory) allows the axle to float a bit on the axle spines in the diff due to tolerances and expansion or contraction due to the change in temperature.

The version on the bottom allows the axle to float a bit in the star of the birf and the splines in the diff to tolerances and expansion or contraction due to the change in temperature.

Quote:
Originally Posted by 4RnrRick
And here is the Camo Method.

This verson allows the axle and Birf assmbly to float a bit on the brass bushing inthe spine, on the splines in the star of the birf and the splines in the diff to tolerances and expansion or contraction due to the change in temperature.

 

[KLF]

Check this out:

Toyota Front Axle Rebuild

I've read that you can find the optimal spot to tack by putting a rubber band around the inner splines and stabbing the axle into the housing and diff, pull it back out and the rubber band will be at the spot where you should put the tack. You can also use duct tape.

 

[weak-link]

rubber band would work If I didn't already have the seals in there.

 

[weak-link]

I had placed the Martack @1" from the end of the shaft, that wasn't deep enough.



I wrapped some tape around the shaft, pushed into the locker. pulled it out and measured it @ 1.5". tack welded it @ 1.5" slamed it back in, took a file to the tack and so far so good.


setup is

UM06 birfields
stock inners
ARB RD33

 

[Sarcastro]

I guess I have my dunce cap on. whats a martack and why would you weld on your splines? the only thing I can think of is to keep the axle from sliding around, but is this really a prob?

 

[GLTHFJ60]

I guess I have my dunce cap on. whats a martack and why would you weld on your splines? the only thing I can think of is to keep the axle from sliding around, but is this really a prob?

Im in his boat. Purpose is to eliminate c-clips so that when you disassemble the knuckle, the birf / axle can be taken out without having to deal with c-clips?

 

[RredFJ40]

see his quoted post above. It lets you leave out the inner birf snap ring so that it's easy to separate the birf from the inner axle.

There are no c-clips in the front axle, GLTH60

 

[Sarcastro]

see his quoted post above. It lets you leave out the inner birf snap ring so that it's easy to separate the birf from the inner axle.

There are no c-clips in the front axle, GLTH60

hmm, i still dont get it, but thats ok, par for the course really

 

[weak-link]

lets put it this way...

You know how a lot of guys in the 60 forum say it takes 2-3 hours to replace a birfield... well a Martack is part of the "15min birfield change"

It makes it so you don't have to put the inner c-clip in the birf, keeping the shaft from going to far into the carrier. If the shaft goes to far in your axle will go past the sealing surface of the outer seal.

A Martack also makes it a lot easier to dig out a broken inner shaft at the birf.


Clear as mud?

 

[weak-link]

bottom of this page shows a missed placed Martack

IH8MUD.com Forum - View Single Post - weak-link's 60 bulid

 

[Pighead]

Im in his boat. Purpose is to eliminate c-clips so that when you disassemble the knuckle, the birf / axle can be taken out without having to deal with c-clips?

Bingo. Trail-side repairs are much quicker with the mar-tack...

 

[lehiguy]

Bingo. Trail-side repairs are much quicker with the mar-tack...

Or eliminated with alltogether with a chomemoly Birfield. Best $400 I ever spent. And yes, I used a martack weld. Just look for the witness marks on the axle shaft where the splines are engaging the side gears. Then make sure it will move in far enough to not bind when you bolt the spindle onto the knuckle. You should have some play there when the wheels are pointed straight ahead.