Welding Old Alloy

Bikes or not. Whatever
User avatar
Bob.Murphy
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 947
Joined: Thu Nov 29, 2012 10:32 pm
Location: Kirkliston, on the West side of Edinburgh.
Contact:

Welding Old Alloy

Postby Bob.Murphy » Tue Jan 07, 2014 7:44 pm

Folks,

I am in the process of restoring a 1931 P&M Panther 500 (Model M50). It was found as a heap of bits in a barn and its going to be an interesting challenge getting it fully restored.

There are a couple of broken castings that I want to weld. One is a mounting for a through-stud on the lower part of the oil tank (no scavenge pumps here you know :lol: ).


Image


The other is on the underside of the 1929 Sturmey Archer LS240 Gearbox - where one of the three mounting studs has pulled out (there was a piece of wood in the hole - keeping the "Gargoil" heavy oil in :D ).


The question is - Does alloy of this age weld OK ?? I have been machining the gearbox end cover to replace the kickstart shaft sleeve and its like turning a sugar cube on the lathe.

If I do it myself I'll be using a Migmate 150 with pure Argon and reversed polarity. I have done some alloy welding but I'm better with steel !

Any thoughts / advice folks ??

Many thanks.

Bob.
(Why didn't I put this on the Panther Owners' Club site ??? Well, its not very active and I'm told that a lot of POC members don't have computers . . ;) ;) ).
My avatar shows the late Len Rich in 1970 with the bike I now have - a 1958 Ariel VH

dave.angus
Posts: 8
Joined: Fri Jun 29, 2012 11:50 pm
Contact:

Re: Welding Old Alloy

Postby dave.angus » Tue Jan 07, 2014 8:39 pm

Would use tig rather than mig but each to there own.

nevhunter
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 4061
Joined: Tue May 10, 2011 9:42 am
Location: Victoria.. Australia.
Contact:

Postby nevhunter » Tue Jan 07, 2014 9:48 pm

Use TIG.. I do a lot of really old stuff. Oil and oxidation are the main problem depending on the porosity of the original casting. Try first on a similar bit of metal to select the rod to use. Prepare well, and use 5% silicon on most stuff. Preheat well especially if the weld is in the middle of a substantial section. Nev

User avatar
daithomas
Posts: 72
Joined: Fri Feb 25, 2011 9:59 pm
Location: South Wales
Contact:

Postby daithomas » Tue Jan 07, 2014 10:32 pm

Could you use a spot-facing tool with a long pilot and machine away the boss down to a good face and fit a piece of drilled alluminium bar to replace the removed metal, check the thickness of material at the bottom first.
If you have access to a lathe. You could make a one time use spot-face from EN8 or silver steel these can be flame hardened. make the pilot to fit in a hole at the bottom and cut the teeth with a hacksaw and file to sharpen
or you could mill away the broken portion with a slot drill if you the the facilities

User avatar
ColinPeck
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 106
Joined: Tue Jul 02, 2013 11:40 pm
Location: Essex
Contact:

Postby ColinPeck » Wed Jan 08, 2014 1:15 am

Hi Bob
I bought my Ariel with a con rod through the side of the crankcase about a 1 1/2" dia. hole, I welded this up with a mig using pure argon by going round the edge of the hole and working my way in. Despite a thorough clean and de-grease beforehand I did get a fair amount of oil coming out of the case from the heat, however this didn't seem to affect anything and "job's a good un". Not sure I'd trust if for a high strength area though, but I'd certainly do it again for a similar repair.
An earlier thread on this forum was discussing alli welding and this product was mentioned (eBay link) http://www.ebay.co.uk/itm/10-Aluminium- ... 2c78c763bf
I have bought some and have a couple of pieces to repair, including a Bantam crankcase with the same half stud hole situation you have. However I haven't had a chance to use it yet and it will probably be a couple of weeks before I get around to it.
If you do a you tube search of the rods there's a very impressive video demonstrating them, impressive enough for me to risk some of my "hard earned" to give it a try. I did buy something similar many years ago but haven't had a lot of luck with them on the few occasions I've tried them, I'm hoping to have better luck with these!
Colin
'53 Bantam, '55 Huntmaster, '61 Bantam, '79 GS 850, 2004 Burgman 650, 2002 Burgman 400

robin.parker
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 275
Joined: Thu May 19, 2011 6:25 pm
Location: Worcestershire
Contact:

Postby robin.parker » Wed Jan 08, 2014 10:25 am

From past experience and disappointments (despite making use of very capable professional help) with ancient and oily ally castings, I'm inclined to agree with Dai, if you can find a way to affect a repair without welding that's the best approach.
Good luck.

User avatar
Bob.Murphy
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 947
Joined: Thu Nov 29, 2012 10:32 pm
Location: Kirkliston, on the West side of Edinburgh.
Contact:

Re:

Postby Bob.Murphy » Wed Jan 08, 2014 1:02 pm

robin.parker wrote:From past experience and disappointments (despite making use of very capable professional help) with ancient and oily ally castings, I'm inclined to agree with Dai, if you can find a way to affect a repair without welding that's the best approach.
Good luck.


This is what I was afraid of. I would prefer to use TIG but I don't have a set and though I could go out and buy one this is not a job I want to learn on.

I have stick and MIG and have been welding (as an amateur) for 40 years. I have books on the subject and check up on the techniques before tackling something new. I know about pre-heating alloy (to the point where sawdust 'sparkles' when sprinkled onto the surface :shock: ).

My worry was distortion. I was thinking that I would have to bolt both halves of the cases together or else bolt the half case to a strong flat surface before heating and welding. Is this an issue I should worry about ?

I am rather reluctant to go to 'experts' as so many prove to be less expert than they claim and I'll only have one shot at this.

I have a lathe and repair stuff without welding where I can.

The kickstart shaft sleeve on the SA gearbox was broken in three places - due to the bronze bush in the kickstart sleeve being worn.


Image


I set the end cover up on my faceplate and machined the sleeve off. I then threaded the hole.


Image


Next I turned-up a new, threaded sleeve.


Image


The new sleeve fits fine. I still have to finish-off the inside and drill the holes for the kickstart spring to locate in but its almost there. I also turned up a new bronze bush for the shaft and pressed it in.


Image


This sounds easy but in practice it took me a few days. The one thing I could have done better was to cut reverse threads - but I'll peg the sleeve to the case to prevent it from coming loose under the action of the kickstart. The spring will also locate it.

On later Sturmey Archer boxes this sleeve was replaceable, so this isn't a new problem ;) .

As a wise man once said "having a lathe does not make you a Machinist" - I have learned a lot :lol: .

Thanks for all the comments folks. I'll have to make a decision sometime soon as I want the bike to be on the road in 2015.

Bob.
My avatar shows the late Len Rich in 1970 with the bike I now have - a 1958 Ariel VH

User avatar
Steven.Carter
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 3645
Joined: Mon Feb 28, 2011 4:45 am
Location: Eastleigh, Hampshire
Contact:

Postby Steven.Carter » Wed Jan 08, 2014 4:42 pm

Looks a tidy job

robin.parker
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 275
Joined: Thu May 19, 2011 6:25 pm
Location: Worcestershire
Contact:

Postby robin.parker » Wed Jan 08, 2014 7:00 pm

Bob,The real experts make no such claim, they just do it for a living. It's the age and old oil that will have found it's way into the porosities of the casting that causes most concern. Super job you did on that kickstart spring housing.
All the best.
Robin

Knud.Degnbol
Holder of a Waxed Cotton Anorak
Holder of a Waxed Cotton Anorak
Posts: 410
Joined: Fri Mar 25, 2011 12:03 pm
Location: Denmark
Contact:

Re: Welding Old Alloy

Postby Knud.Degnbol » Wed Jan 08, 2014 9:41 pm

I have been inspired by your story. I have an Ariel model A with the same gearbox, which have a worn bush for the kickstart. I might need to do the same to that.
Knud


Return to “Main Chat Forum”

Who is online

Users browsing this forum: No registered users and 4 guests