Australian Belly Tank

[Dr Goggles]

I'm edging ahead on the differential transplant job....

I had a crack at removing the plug welds that hold the axle tubes into the centre housing on the weekend, I am not exactly sure where the material sits on the *GRTOH( generally recognized table of hardness)but it was harder than what they make drill bits out of....I had a certain Colonel suggest cobalt drills....I baulked at the price and anyway I flattened the tip of my centre-punch on it, another suggestion was stellite... but they'll cost me $200 and then I still have to mount the diff centre somewhere on my drill press table and that strikes me as potentially troublesome.

The maintenance man at work Markput me onto a small engineering works out near the airport ...."Yeah, we'll have a look at that, we'll be able to get them out"....so I'm off to see Stephen on Saturday morning. I will take the chunk of hollow bar that I got yesterday which will be used to turn up the inserts which we'll use to slide into the axle tubes and attach the new diff centre . It is 50 ID by 70 OD , it wasn't cheap ...

*
1./ Harder than goats knees.
2./ Harder than chinese algebra
3./ Harder than a mother in law's stare

[Milwaukee Midget]

As long as it's less than 7, you'll be fine.


*
7./ Harder than the determination of an Aussie salt racer.


 

[generatorshovel]

Doc,
While deciding what material to use for my supercharger drive shaft I ran it past my friendly engineering guru, and to my surprise, he suggested I use a grade 8 bolt,
I asked him if it would machine ok  and yes,,it did, both in the lathe and then drilled and tapped.
Your axle housing must be some pretty weird stuff mate ?
T'fer

[Dr Goggles]

 I could have a crack at them with a torch but the housing is either grey or graphite iron and will likely let go before the weld . The welds look to be about half an inch dia. and as I said they are so hard that they took the point off a centre punch, I made a well in one with a burr ( so a drill could at least start)but a bit still just felt like it was sitting in a bearing, made heat and made the bit blunt but that was it.

All of the welds have a bubble in the top of them which makes it look like they were very hot and then probably because of the bulk of the housing cooled very quickly and are probably pure martensite.

[SPARKY]

we take them out with a torch----leaves room for BIG rosett welds    thought about trying a hole saw!!!

[wobblywalrus]

A stone bit in an angle grinder?

[Dr Goggles]

we take them out with a torch----leaves room for BIG rosett welds    thought about trying a hole saw!!!

I was standing there with my set of hole saws......and thought hmm , nah...... pretty hard to wrangle one of those without a guide bit in it....

I figure annealing them and drilling or a torch is probably going to be the final chapter in this short but thrilling story.........

I need to get the insert pieces turned and so I'm going to take it all to the above mentioned workshop and see what they reckon.....

A stone bit in an angle grinder?

anything that is small enough to get to them doesn't have enough edge speed to do anything, except the die grinder and with the amount of progress it made I estimated the entire job to take about 3 infinitys........

I'm pretty sure Sparky will get the biscuit on this one, for cryin' out loud he's done it before.......

So, Bill do you run a shrink weld around the inside of the tube after you blow the the plug welds out or what?

c'mon give over..

[Rex Schimmer]

I like Sparky's hole saw idea but you would need to do it on a mill that way you can clamp the housing to the mill table and then you will not need a guide drill on the hole saw. I would think that a hole saw that is somewhat larger in dia than the factory weld should be out side the heat affected zone and the material might not be diamond hard. I know you guys are probably like me and don't "just happen" to have a mill standing in the corner of your shop. Maybe if you have a "Jigajoint" cutter set up for doing tubing ends you could "adapt" it to work on your housing. I also like the "blue wrench" method but it is messy.

As the saying goes: "If it was easy ever (insert your favorite minority here) would be doing it"!!

Rex

[SPARKY]

When we took the tubes out of the Caddy 10-12 we tried several things.  But the way we got them out was to cut the plugs out and rotate the housing with a 36" pipe wrench to make sure that it was all out then cut the tube off flush, then carefully cut it out of the housing. inserted the new tubes and allinged the new tubes. We hard tacked the out side with 3 welds but did not weld insided at all for this was a frt driving axle and we need to be able to install an inner seal.  we are now working on another that we will tack inside and out before we reweld plugs completely

[Dr Goggles]

When we took the tubes out of the Caddy 10-12 we tried several things.  But the way we got them out was to cut the plugs out and rotate the housing with a 36" pipe wrench to make sure that it was all out then cut the tube off flush,

Had the angle grinder not been making such a racket I might well have heard the little voice in my head saying " nay laddy! dooon't cut the toooobs off yet".....

As it stands they are cut off flush, I'll report back on Saturday with what I hope is a successful extraction........

[maj]

Yeah a bit late once cut, 
for removing the shaft from a PTO coupler we weld a chunk of steel to the shaft then drive it out with a big hammer.
is there a step on the inside ?, could it be pressed in ?

[SPARKY]

Majs idea is workable-- we  made a crude version of a cam brg tool-- insert a big bar from the other side, get a BIG sledge and bang away on the "slotted remains"

[gidge348]

If you are having problems drilling anything a trick I learnt from an old engineer is to get a masonary bit....

(yes masonary as in concrete) and then grind a face on the bit.

I do not know what they make those tips out of but I guarantee it will drill through anything.....

Regards

ian...

[Peter Jack]

If you decide to use a torch, why don't you find someone with a plasma cutter instead. It would do a much nicer job.

Pete

[Dr Goggles]

If you are having problems drilling anything a trick I learnt from an old engineer is to get a masonary bit....

(yes masonary as in concrete) and then grind a face on the bit.

I do not know what they make those tips out of but I guarantee it will drill through anything.....

Regards

ian...

Stellite probably..Rockwell C 60-62 hardness even into the "red" range so it works by heating the job til it softens...that's what the little piece is in the tip of the masonry bit......it's a lot cheaper than a stellite drill

If you decide to use a torch, why don't you find someone with a plasma cutter instead. It would do a much nicer job.

Pete

That's what I'm taking it to the engineers shop for, convenience and neatness..............The Colonel has a plasma cutter, but it wouldn't touch that sort of thickness, maybe the shop does ..