No/Low machining welding

[weyland]

Greetz guys,

Have a question I came up with during a sleepless night...

Say you had a piece of aluminum that had a hole drilled/bored in it, and that hole had a crack running to/around it that you wanted to weld up.

The kicker is that you want to minimize/eliminate re-machining the hole after welding.

Can you simply plug the hole with a proper fitting plug of something like tool/carbon/stainless steel, and then weld the aluminum?

What about using graphite for a plug?

The thinking being that the aluminum being applied by the welding process wouldn't stick to the plug being used, thus minimizing the necessity to re-machine the hole.

Thoughts? Ideas?

Best,

Weyland

[R. Nelson]

Re: No/Low machining welding

Originally posted by weyland
Greetz guys,

Have a question I came up with during a sleepless night...

Say you had a piece of aluminum that had a hole drilled/bored in it, and that hole had a crack running to/around it that you wanted to weld up.

The kicker is that you want to minimize/eliminate re-machining the hole after welding.

Can you simply plug the hole with a proper fitting plug of something like tool/carbon/stainless steel, and then weld the aluminum?

What about using graphite for a plug?

The thinking being that the aluminum being applied by the welding process wouldn't stick to the plug being used, thus minimizing the necessity to re-machine the hole.

Thoughts? Ideas?

Best,

Weyland

Hey Weyland, are we talking cast aluminum? How thick of material?

[lranch]

That's a good one! Not looking at the part, load type,path,etc, the best solution I can suggest would be to install a threadsert. This is a threaded object designed for compression joint attachment of soft metals ie, aircraft panels etc. Size the hole for the device, tap in from back, then use compression tool to seat. If hole doesnot require threads remove them with drill. The thinking here being that the insert will displace cracks, that is, insert hole will remove damaged material. The other method would be to core out damaged area, turn down od of round stock for tight fit, drill (leave enough wall material to stay away with torch), part off at thickness, then weld around. Best I can do with info provided. Good luck.

[DaveH]

Back and clamp the piece with some scrap steel. Use the original hole as a guide and drill the steel. Weld the aluminum area around the hole with the steel still clamped. After welding, drill the aluminum using the hole in the steel as a guide.

[Guest]

I've used graphite plugs many times in a critical situation like this and it works great. Machine the plug to the shape you want, and weld away! Then after welding if you can't just pull it out, bust it up.

[weyland]

Re: Re: No/Low machining welding

Originally posted by R. Nelson
Hey Weyland, are we talking cast aluminum? How thick of material?

Well, in this case, yes.
But my question seems, to me, irrelevant of
the type of aluminum as far as cast or not.
Am I incorrect here?

As for thickness -
In this particular case, it's approximately .750" and the bore is .561".
Again, though, my question pertains more to the theory of plugging the hole/bore to save machining time later.
Is the thickness a concern here?
(I do understand that in thinner sections you'd get some distortion no matter what)

Thanks for any help,

Weyland

[weyland]

Originally posted by lranch
That's a good one! Not looking at the part, load type,path,etc, the best solution I can suggest would be to install a threadsert. <snip> Size the hole for the device, tap in from back, then use compression tool to seat. If hole doesnot require threads remove them with drill. The thinking here being that the insert will displace cracks, that is, insert hole will remove damaged material. The other method would be to core out damaged area, turn down od of round stock for tight fit, drill (leave enough wall material to stay away with torch), part off at thickness, then weld around. Best I can do with info provided. Good luck.

Thanks for the reply, but we're speaking of a bore or hole that is already sized and critical in normal operation (like a bore for a bearing), and so is not available to be bored larger. Hence, the original idea of plugging with a disimilar material that won't stick to the aluminum being applied.

Best,

Weyland

[weyland]

Originally posted by DaveH
Back and clamp the piece with some scrap steel. Use the original hole as a guide and drill the steel. Weld the aluminum area around the hole with the steel still clamped. After welding, drill the aluminum using the hole in the steel as a guide.

Excellent idea Dave. Consider it viked.
But in this particular case, the hole is a precision one, and so a drill won't do here.

I'm still stealing the idea though~! (:>)

Best,

Weyland

[weyland]

Originally posted by Rocky D
I've used graphite plugs many times in a critical situation like this and it works great. Machine the plug to the shape you want, and weld away! Then after welding if you can't just pull it out, bust it up.

Excellent. Thank you, Rocky~!
I thought as much, but wanted to know if others had tried it with any success. I'd only done it with brazing and silver solder.

I have the ability to re-machine the bores fine, but I'm interested in cutting my labor down where possible.

In answer to everyone's nagging question -

This is a 1974 Harley Davidson Sportster engine case. Cast aluminum. And the bores are for the cam bearings in the right side case half.

The back side (inside of motor) of the case is cracked from improper installation of the bearings previously by someone else.
My thinking was to weld up the fractures so that nothing more happens, but wanting to reduce any machining time by plugging the bores with graphite before doing so.

Can this be done with a plug of stainless steel or tool steel? Or will they melt/bond/contaminate with the aluminum?

Thanks to everyone for their great replies~!

Best,

Weyland

[Hobart Expert Rock]

HI WEYLAND.....MY 1970 XLCH HAD BRONZE SLEEVES IN THEM FOR THE CAMS TO RIDE IN............ GRANTED 900CC VS 1000CC I CAN'T SAY AS I'VE EVER LOOKED AT THE BEARING RACES (SLEEVES) IN YOUR VINTAGE................WELL LET US KNOW HOW IT WORKS OUT............ WHAT DID THE LOCAL HD GUY SAY BUY THESE NEW CASES.........HAHAHA............ I HAD A 1940 SPRINGER WITH FREEZE CRACKS IN THE SPRINGER LEGS......... WELDED SEVERAL YEARS AGO WITH CHROME ROD, STILL LOOK NICE AND NO RUST............... HD GUY SAID THROW THEM AWAY....HAHAHA... WHAT A RIOT................I WORK FOR A WELDING COMPANY THAT CAN WELD MOST ANYTHING....................BE SAFE............ROCK[email protected]

[Guest]

Originally posted by weyland


Excellent. Thank you, Rocky~!
I thought as much, but wanted to know if others had tried it with any success. I'd only done it with brazing and silver solder.

I have the ability to re-machine the bores fine, but I'm interested in cutting my labor down where possible.

In answer to everyone's nagging question -

This is a 1974 Harley Davidson Sportster engine case. Cast aluminum. And the bores are for the cam bearings in the right side case half.

The back side (inside of motor) of the case is cracked from improper installation of the bearings previously by someone else.
My thinking was to weld up the fractures so that nothing more happens, but wanting to reduce any machining time by plugging the bores with graphite before doing so.

Can this be done with a plug of stainless steel or tool steel? Or will they melt/bond/contaminate with the aluminum?

Thanks to everyone for their great replies~!

Best,

Weyland

Not steel, Weyland, use graphite .The steel will liquify and give your weld fits! The amount of heat used to weld the aluminum will vaporize the steel. Nix on brass and copper, too.

[weyland]

Originally posted by Hobart Expert Rock
HI WEYLAND.....MY 1970 XLCH HAD BRONZE SLEEVES IN THEM FOR THE CAMS TO RIDE IN............ GRANTED 900CC VS 1000CC I CAN'T SAY AS I'VE EVER LOOKED AT THE BEARING RACES (SLEEVES) IN YOUR VINTAGE................

No, no, no...
I think you're confusing the right case half with the outer cam cover. The cam cover has the bronze bushings in it, but all Sporty and K models had needle bearings in the right hand side case half. (what the cam cover mounts to)

WELL LET US KNOW HOW IT WORKS OUT............ WHAT DID THE LOCAL HD GUY SAY BUY THESE NEW CASES.........HAHAHA............

Screw Harley.
I've no love for the company, only the bike.
I wouldn't go to the stealership for _anything_.
If I can't buy it aftermarket, I'll make it.
And I'd rather it be that way.
I made most of the parts on my bike, and have been doing so for over 15 years.
This bike for the Ol' Lady will be no different.

I HAD A 1940 SPRINGER WITH FREEZE CRACKS IN THE SPRINGER LEGS......... WELDED SEVERAL YEARS AGO WITH CHROME ROD, STILL LOOK NICE AND NO RUST............... HD GUY SAID THROW THEM AWAY....HAHAHA... WHAT A RIOT................I WORK FOR A WELDING COMPANY THAT CAN WELD MOST ANYTHING....................BE SAFE............ROCK[email protected]

Yeah, that's exactly the attitude I'm talkin' about.
I'm more interested in keepin' my iron on the road than I am in giving them my money.
Man, I _LOVE_ those older springers. About the classiest front end ever made in my humble opinion.

I've been documenting the project on our website, and plan on taking pictures during the whole process, including the welding of the cases.
(right now I'm rebuilding the flywheels)
If you want, I'll post a link to the page so you can see how it goes.

Thanks for the help~!

Best,

Weyland

[weyland]

Originally posted by Rocky D


Not steel, Weyland, use graphite .The steel will liquify and give your weld fits! The amount of heat used to weld the aluminum will vaporize the steel. Nix on brass and copper, too.

Okay, kewl. Thanks. That's exactly what I was afraid of.

Best,

Weyland

[Hobart Expert Rock]

WEYLAND.........POST IT I FOR ONE WOULD LOVE TO SEE IT...... AND YOUR RIGHT I'M THINK WRONG SIDE COVER........HAHAHA... I TOO LIKE TO REPAIR THINGS..............I'VE HEARD THE STEALERSHIP THING BEFORE...............AND I MUST CONFESS I HAVE A PILE OF HARLEY SHIRTS FROM DIFFERENT SHOPS I'VE VISITED.......... YES I'VE BEEN TO YORK PA WORKING ON EQUIPMENT AND TRIED TO TALK THEM OUT OF A SIDE HACK TO FIT MY 49 BUT TO NO AVAIL...........ALSO BEEN TO SOME OF THE ONES IN MILWAUKEE....................... YOU KNOW THE MUSEUM IN YORK HAS SEVERAL SIDE HACKS WONDER WHY THEY WOULDN'T GIVE ME ONE............HHMMMMMMMM........BE SAFE AND TAKE CARE............................MAKE IT HAPPEN WITH THE POSTING.....ROCK
[email protected]

[weyland]

Originally posted by Hobart Expert Rock
[B]WEYLAND.........POST IT I FOR ONE WOULD LOVE TO SEE IT...... {/B]

http://www.varangiankindred.org/starlyng/critter.htm

YES I'VE BEEN TO YORK PA WORKING ON EQUIPMENT AND TRIED TO TALK THEM OUT OF A SIDE HACK TO FIT MY 49 BUT TO NO AVAIL...........ALSO BEEN TO SOME OF THE ONES IN MILWAUKEE....................... YOU KNOW THE MUSEUM IN YORK HAS SEVERAL SIDE HACKS WONDER WHY THEY WOULDN'T GIVE ME ONE............HHMMMMMMMM........ROCK
[email protected]

Stingy, ain't they? (:>)
You'd think with all those side hacks layin' around, and all that your company has done for'm, they'd be knockin' yer door down to give ya one, huh? (:>)

Oops, back to reality...

More updates and pics for the site are on the way, but I probably won't have them posted until the weekend due to time.

Best,

Weyland