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ahidley
06-06-2008, 07:47 AM
Ok, Customer wants to change to a differant engine in his jetski. Thats no problem. He wants the Drive shafts to be cut and welded, Thus use the front half from one ski and the other half from the other ski. This will make the splines on both ends fit. So the question is what kind of welding rod do I use? Material looks like stainless but is rusty in spots. It also is magnetic. The two shafts that will be joined are from to differant manufacturers. Not a clue what kind of steel either one is. If I use 7018 and the base metal is stainless will that bond to stainless? If I use stainless rod and the base is steel, will it bond? The driveshaft is solid and is about .825 in diameter

torker
06-06-2008, 08:39 AM
That's actually a tough call.
No.. don't use 7018. An 8018, 9018 or 11018 would get you closer but still not right.
EG... welding most SS to mild steel you should use E309 (or E310).
not your case.
For welding 304 SS you need E308 and so on.
If it's 303SS you shouldn't weld it.
It's hard to tell you exactly what rod to use.
Some of the guys here may know or have a better guess what the shafts are made of.
A smallish shaft like that is best welded with tig but if you are careful with inclusions you can use stick.
Guess that didn't help much huh?
Was me in an emergency I'd try E11018... cuz I keep that on hand and have used it to weld "mystery" SS.
Russ

wierdscience
06-06-2008, 08:54 AM
You need to narrow down on the type steel it is first.Try the magnet again,first on the shaft and then on another piece of low carbon steel.If the pull is the same then it most likely is steel of some sort.If it is less on the shaft then it might be SS,but probably something not easily welded.

Some of the jetski mfgs like to use 1045 that they then chrome plate,7018 would be fin for that,better would be 8018 or 9018 like Russ mentioned.

Others like 8620 which can also be welded.

There are a few though that use Aquamet stainless,but I doubt that's what you have since your seeing rust.

torker
06-06-2008, 09:13 AM
Thanks Darin.. kinda thought you'd jump on this one. I've never had anything to do with jetskis so have no idear what shafting they'd use.
I can tell however... I have recently leaned on a jetski... I took one in on trade and just kinda lean on it once in awhile.
I may stay at a Holiday Inn soon as well then I'd be an expert on the things ...no? :D
Russ

lazlo
06-06-2008, 09:25 AM
Some of the jetski mfgs like to use 1045 that they then chrome plate,7018 would be fin for that,better would be 8018 or 9018 like Russ mentioned.

Are the shafts hardened? If you weld on it, you're going to anneal it...

wierdscience
06-06-2008, 09:30 AM
Here you go Russ,just what you need:D

http://www.youtube.com/watch?v=Nq8Fn55axd4&feature=related

wierdscience
06-06-2008, 09:32 AM
Are the shafts hardened? If you weld on it, you're going to anneal it...

Sometimes yes,sometimes no.At least it's a jetski so it's only running a pump impellar,not too much shock loading to worry about.

ahidley
06-06-2008, 10:55 AM
I'll try the magnetic differance and see.
I think that there is a LOT of shock. That thing is in and outa the water every 5 seconds for its entire life.
Customer said one seemed harder than the other with a "file test".
I'll post a pic tonight of the two shafts. Perhaps the color of them will be a tell tale sign ...........

oldtiffie
06-06-2008, 11:02 AM
I think I'd discuss it with my insurer first!!!

Forrest Addy
06-06-2008, 11:52 AM
An over the fence guess on the correct welding filler to be used on a highly stressed part? I wouldn't touch that with a ten foot pole. If there's room I might consider a silver brazed sleeve but then the heat may detract from the strength of the shaft.

Nope. Send the man down the road. There's the possibility the shaft will fail stranding the dufus is out on the briney. That's a tort action waiting to happen.

shawnspeed
06-06-2008, 12:35 PM
#1 I would Tig weld that shaft , not stick weld.#2 I would make a sleeve that is fitted to the shaft, slide it on before mating the ends, weld the shaft together check for straitness,correct if neccisary,dress the weld,slide sleeve over welded joint and plug weld sleeve to shaft,along with welding around the ends of the sleeve. check for strait again.....now having said all that..I would strongly suggest you seek out someone that can make you a splined shaft to meet your needs...if the splines are out of alignment (concentric) it'll beat the snot out of the crank bearings & pump bearings ....rapidly.....Good luck Shawn

torker
06-06-2008, 08:15 PM
An over the fence guess on the correct welding filler to be used on a highly stressed part? I wouldn't touch that with a ten foot pole. If there's room I might consider a silver brazed sleeve but then the heat may detract from the strength of the shaft.

Nope. Send the man down the road. There's the possibility the shaft will fail stranding the dufus is out on the briney. That's a tort action waiting to happen.
Holy Geezuz.. I'm glad I don't live down in the US sometimes. You guys are scared to take a crap sometimes.
Nobody said anything about being stranded in the middle of the Atlantic... unless I missed something.
I weld crap like this all the time and have for years... that's what weldors do.
If I'm really concerned I get hold of the mfg. and ask what the shaft is made of.... simple as that. If it can be welded i weld it...if not I don't.
I think it comes down to ability???? I've had hundreds of my welds tested and have a good idea how it should be done. I judge what I can and cannot do because I take the time to learn what is weldable and what isn't.
Giving ANY advice on the net is a crapshoot.
Forrest... I've read you stuff for years. What if I misunderstood a little thing you said about damn near anything and hurt myself.. aren't you concerned that I may sue you?
And tiffie... how the hell do you justify your comment after showing everyone how to use a drill press vise and a piece of flat bar to equal a Kurt vise????
Welding is welding.. there are proceedures.. if you follow them you are protected by law. If you use your best guestimation as a qualified weldor (as we sometimes have to) and don't do anything blatantly stupid... you are also protected by the law... at least up here you are.
You all need to quit crying wolf all the time (or he may come back) :D
Russ

wierdscience
06-06-2008, 08:41 PM
Cash money,no ticket = no tort,they can pound sand without proof you did anything.

With that said I won't do things that might endanger the general public,crappy tow hitches stupid car mods that sort of thing,of things that are just plain stupid,those guys don't pay anyway.

If he is running his jetski out of sight of land he is a fool and will die sooner or later wether somebody welds his shaft or not.

The worst part of the job will be getting it straight:D

oldtiffie
06-06-2008, 10:34 PM
And tiffie... how the hell do you justify your comment after showing everyone how to use a drill press vise and a piece of flat bar to equal a Kurt vise????

Easy - I need a clear conscience - but not a list of cleared assets!!. and I certainly did not equate it to using a "Kurt" vice. I did advise caution as well!!! And for what its worth, that same method is in just about any web site or hand-book/manual on shaping machines!! And they are still advertised and sold on the net.

If you recall, after a similar "comment" (adverse) about putting that post of mine up for "newbies" and that I had been taught how to use it and that they may not etc. etc. I withdrew it in deference to your comments.

I think that if a rule is going to be applied it should be pretty well universal if it is published without caveat by a very experienced weldor who may well make it look "all too easy" to a lesser competent person or one who is less well advised.

It is all too easy for a "what I would/can do/did" to be taken as a "go for it" by others.

torker
06-06-2008, 10:55 PM
Sorry tiffie.. I don't agree. All over the web are pages of info regarding proper welding proceedures etc. It is not magic. Like I said.. it comes down to "if you can do it". Not everyone can weld. Not everyone can sculpt a weld puddle as required. This is a highly technical manual skill. It's a hell of a lot different than cranking handwheels to a predetermined number.
The poster seemed to know how to weld and was asking which electrode to use. That is all he asked. He did NOT say.. "I don't know how to weld so...."
As for the vise deal... yup...you deleted it...kudos to you. Lets not chase that horse any further.

tattoomike68
06-06-2008, 10:56 PM
stainless is garbage, use some jet rod on a sleave so it cant bust. Iv worked on all kinds of drivelines for farmers and loggers and every other type of person who runs machines balls to the wall.

I think some 7018 wire from a wire feed will work fine, any tougher than that and a part will bust that cost a fortune.

Its not rocket science..

ahidley
06-07-2008, 12:35 AM
Heres the pic
http://i194.photobucket.com/albums/z80/ahidley/post.jpg

The rust musta been from what it was touching because it wire brushed right off. The magnitism was the same as a piece of 12L14.
I ended up using E309 rods in the stick welder. I put a pin in the joint and Ved it out. I then put it in the lathe and put a center in the end and welded it right in the lathe. Then where it was welded I turned it down. It warped alittle, bout .010 at the end where the splines are, The 2bearing surfaces aRE parallel. So I think that the clearance in the splines will allow all to be happy.

Thanks for all your input.

Fasttrack
06-07-2008, 01:16 AM
I like stick welders :D

Everytime I see a post regarding welding I have to chime in on behalf of stick welders. I think they are often under-estimated and under-apreciated. If you know what your doing, you can make as good and better welds in most material as you can with other methods.

Nice job getting it done. I can see Forest's point but if it fails in this case, it is unlikely that it will cause serious trouble. Maybe just some shrapnel up the a@@ :eek:

tattoomike68
06-07-2008, 01:20 AM
I like stick welders :D

Everytime I see a post regarding welding I have to chime in on behalf of stick welders. I think they are often under-estimated and under-apreciated. If you know what your doing, you can make as good and better welds in most material as you can with other methods.

Nice job getting it done. I can see Forest's point but if it fails in this case, it is unlikely that it will cause serious trouble. Maybe just some shrapnel up the a@@ :eek:


Stick is golden, we know its true.:cool:

oldtiffie
06-07-2008, 01:35 AM
OK - job done - no comment on that score.

But there is another potential "sleeper" here.

If I were welding anything in a machine - particularly a lathe, I'd make damn sure the weld to earth circuit was as short and as good as you could get. Make sure that it is definitely not such that the circuit was through or across any bearing surfaces - whether they be "round" (bushes/ ball or roller) or "flat" (guides). If so it may cause "arcing" and "etching" on or across the bearing or polished surfaces. Same applies on "V" blocks and the like - the list goes on and on.

I particularly remember this from the Navy where things like gun or director turn-tables were concerned. There were lots of others.

A poor quality "local/main" "earth" may give cause or rise to other stray or parallel circuits where they should not happen.

Weld spatter has its own list of potential but not unrelated problems as well when welding on or near machine surfaces.

torker
06-07-2008, 07:47 AM
See this yellow thing? The mud rail I built about 10 years ago. Started with a nitrous SB Chevy and progressed to a 572 blown alcohol engine capable of near 2000 hp. I sold it two years ago minus the motor. It now has a 540 engine that's probably making around 2700 hp.
It's 4wd and has no transfer case. It uses a D60 chain drive setup I built using pieces of 4140 with automotive splines (both male and female) welded together. Same thing.. I got a machinist to bevel them add a center pin then welded them with a STICK welder.... a portable no less.
I had no lathe at the time so I ground and shaped the welds by hand with an angle grinder(I also couldn't afford to hire the machinist to do it on the lathe).
That thing was pounded through some pretty ugly mud pits over the years. Three weeks ago the guy barrel rolled the car 3 times.
Not one of those shafts has ever broken.
http://img.photobucket.com/albums/v210/torker/Hairy_Kanary_2.jpg
I still remember all the "experts" telling me the thing would never work... I'd be killed... my grannie would eat my homework..
Oh ya... you should read the first four words of my original post..
Russ

bob308
06-07-2008, 09:44 AM
well russ we do agree on some things. this liabity thing should not even be allowed on here.

if you are that scared to do anything what are you doing here?

i have seen alot of thing welded that i would not even heard of one guy narrowing rears and cutting and welding the axles.

now back to question why not make a new shaft?

lazlo
06-07-2008, 09:54 AM
now back to question why not make a new shaft?

I was wondering the same thing Bob. Maybe it's just picture distortion, but the splines here look pretty distorted:

http://i194.photobucket.com/albums/z80/ahidley/post.jpg


It warped alittle, bout .010 at the end where the splines are, The 2bearing surfaces aRE parallel. So I think that the clearance in the splines will allow all to be happy.

torker
06-07-2008, 10:08 AM
Robert.. I think those splines are supposed to look like that.
The Nascar boys use a similar spline so they can warp the rearend housings to change the rear camber or whatever other tricks they have up their sleeve.

doctor demo
06-07-2008, 07:37 PM
well russ we do agree on some things. this liabity thing should not even be allowed on here.


now back to question why not make a new shaft?
Hi Guys, What I don't understand is why not just cut some keyways in the shafts and use a coupling , then you could chang motors 'till the cows come home.
F the liability , short of knowing something is suisidal:eek: the customer gets what the customer pays for.
Steve

Mad Machinist
06-07-2008, 07:44 PM
I wouldn't touch it unless I cut the tube away completely form both splines....then made a new shaft using the old ends after they are machined to a .001 interference fit in the new tube. then you could pick the material for the shaft:D With the rpm you are dealing with in a ski....only way I'd do it.

Looks like my suggestion is irrelavelent.....didin't realize it was a solid shaft. I do however tig all drive shaft work.

bob308
06-07-2008, 09:34 PM
i looked at the pic of the shaft. i think the splines could be made that way so the shaft would not bind when the motor and drive flexed.

the keyed and sleeved idea would work too. like the pto on a tractor.

ahidley
06-08-2008, 12:06 AM
The splines are straight on one end and the other end they are shaped kinda like a football. This is because the drive shaft is mounted in the ski via bearings on both ends and the engine is on rubber mounts. This way the motor can actually move around in a circle , not just in and out with straight splines.

I put blankets all around the lathe while welding. I also thought about the bearings being arched so I clamped the ground on the shaft right next to where I welded it.

I thought about making a new shaft also. Customer wants to save $. Welding a now usless shaft into a good one made more sense to him.