Thanks: 0
Likes: 0
Needs Pictures: 0
Picture(s) thanks: 0
Results 1 to 15 of 28
Thread: How do I weld Cast???
-
13th November 2008, 04:10 PM #1Novice
- Join Date
- Jul 2008
- Location
- Berrigan
- Posts
- 17
How do I weld Cast???
G'day Guys,
I have recently bought a small CIG inverter welder for some home hobby stuff. I have some experience with stick and taught myself the basics of TIG in the last few days.
I am trying to use some old pulley's and gears to make up the base for a set of bar stooles and table. I presume they are of cast iron???
How do I weld it and can i weld it to mild steel???
I have tried with the stick and mild steel rod's but the weld is veryn brittle and has no real strength.
Any suggestions...
cheers
-
13th November 2008 04:10 PM # ADSGoogle Adsense Advertisement
- Join Date
- Always
- Location
- Advertising world
- Posts
- Many
-
13th November 2008, 04:24 PM #2
I don't know about welding cast to something else but a bloke in Cairns repaired a cracked cast iron planer table for me using Spray Facing Powder, the stuff that is used to put hard facing on mower blades & dozer blades etc.
Cliff.
If you find a post of mine that is missing a pic that you'd like to see, let me know & I'll see if I can find a copy.
-
13th November 2008, 05:38 PM #3GOLD MEMBER
- Join Date
- Jun 2007
- Location
- sydney
- Age
- 64
- Posts
- 3,566
I have welded cast iron to stainless using mig and rods both fillers were nickel not sure how it would work with steel.
The rods are dear as well as the wire but ask around you maybe able to purchase a couple and give it a try.
-
13th November 2008, 07:38 PM #4
you can get special rods or welding cast and welding othr steels to cast. cant remember what they are called give a welding joint or similar a ring
www.carlweiss.com.au
Mobile Sawmilling & Logging Service
8" & 10" Lucas Mills, bobcat, 4wd tractor, 12 ton dozer, stihl saws.
-
13th November 2008, 07:38 PM #5SENIOR MEMBER
- Join Date
- Feb 2004
- Location
- kuranda north qld
- Posts
- 717
try bronze filler rod flux and an oxy torch . cheers bob
-
13th November 2008, 07:51 PM #6
Did in the past weld Cast using Nickel rods on an Arc welder. Doing it other ways caused cracking to the material due to expansion. TIG might work.
StudleyAussie Hardwood Number One
-
14th November 2008, 12:02 PM #7
We need Grahame here. My understanding is that you have to clean the hell out of the pieces to be welded, then use an oxy torch to heat the metal until it turns orange, then weld it using special cast rods, then leave it alone to cool naturally.
-
14th November 2008, 01:24 PM #8Novice
- Join Date
- Jul 2008
- Location
- Berrigan
- Posts
- 17
What I have found out so far...
I called a welding place today, they said it can be done with med.- high nickel cast rods.
They will sell them to me on a per rod basis for about $5 per 3.2mm rod. or $160 per kg.
They also had what they called disimilar rods which are used for welding metals that are different eg steel to stainless etc. but they will also do spring steel and high tensile. They couldnt confirm if they would do Cast?? They are $115 per kg.
Total Tools had the high nickel cast rods but they were selling for about $114 for a packet of 12 - 15 rods.
I'll try to track down a place where i can them abit cheaper...
-
14th November 2008, 01:34 PM #9
My understanding is similar to Ross', the parts need to be heated first so there is no thermal shock when welding begins, and a slow cooling (no quench) for the same reason.
I have done a few jobs, but not with arc rods, just Oxy-acet and a brazing technique.
CheersAndy Mac
Change is inevitable, growth is optional.
-
14th November 2008, 02:16 PM #10GOLD MEMBER
- Join Date
- Jun 2007
- Location
- sydney
- Age
- 64
- Posts
- 3,566
All the welding of Stainless to Cast Iron that I have done has allways been done Cold ,no preheat.
Not sure in this application how vital Pre heating maybe.
There are times that I have had to Pean the welds to relieve stress.
-
14th November 2008, 02:24 PM #11
From memory you must preheat to fusion weld with Oxy. So the whole job gets pretty hot, then you heat the area you are welding enough to melt it. Cast runs like butter when it melts so careful. You use a rod to add material to it.
StudleyAussie Hardwood Number One
-
14th November 2008, 09:02 PM #12
Hi Guys,
Cast iron is something you don't weld unless you really ,really need to.
Welding cast iron to itself presents enough problems but welding it to something else,well it just gets more difficult.It not a job for a novice welder.
The reason is that cast iron has 100 times the amount of carbon it it than say a piece of mild steel.Add carbon to a ferrous metal and subject it to welding temperatures and hardening will occur.
The more carbon ,the more hardening.
Is there a picture forming here yet?
So whether you are weld Ci to itself or something else there is going to be a very hard area along the bead boundary .
The other pain in the rrse charecteristic of good old CI is the shrinkage rate as it cools. In short the little inverter machine will be hard pushed to weld your cast iron and produce something you will be happy with.
Another problem that arises is that all cast irons aren't equal as there are several. I would guess your pulley bases are grey cast iron which is machinable.
If you can't be swayed from stick welding, use a pure nickel rod as first choice, a stainless steel 316L electrode as next choice and finally a low hydrogen electrode as the cheapest ,but nastiest choice .I think what will ultimately dictate your choice is the cost of the electrode,be sitting down when you get the price!
However, if you can be convinced not to stick weld ,pally up with someone who has an oxy set and braze the job - best option of the lot.
Does that help?
Grahame
-
15th November 2008, 07:10 PM #13Novice
- Join Date
- Jul 2008
- Location
- Berrigan
- Posts
- 17
Thanks Grahame,
I dont have an oxy set or any experience with oxy welding so I will have to stick to the arc option. Though I may be able to change the method of construction and use a large bolt through the center of the pulley form the under side and weld a nut to the inside of the vertical mild steel pipe.
I have heaps of old gears/pulleys sitting around so I might try it anyway just to see what happens.
Thanks for the info on the welding options
cheers
-
16th November 2008, 09:42 AM #14
g_man,
Ok! If you have to stick weld!
- Preheat the cast to cherry red -or if its a large piece as hot as you can get,
- Weld it.
- Cool it out slowly- A tub of lime in which the recently welded item is buried in- come back 24 hrs later-slow cooling is the trick -if its going to work at all-
if it doesn't work toss the lime into an acid soil part of the garden -Lol
As one of the other blokes said ,you might try a welding works to see if they will sell you just 1 rod.
Cheers
Grahame
- Preheat the cast to cherry red -or if its a large piece as hot as you can get,
-
16th November 2008, 11:08 AM #15
For Cast iron welding this is the go.
Although the powders are expensive in the long run it works out cheaper because it works first time around.
Kev."Outside of a dog a book is man's best friend ,inside a dog it's too dark to read"
Groucho Marx
Similar Threads
-
How do I TIG Weld 1mm Aluminium
By Watts2759 in forum WELDINGReplies: 23Last Post: 23rd August 2011, 09:28 PM -
Learning to weld. Where to start?
By Maxwellbest in forum WELDINGReplies: 10Last Post: 2nd August 2008, 05:10 PM -
Cast Iron Weld Repair
By Woodlee in forum WELDINGReplies: 4Last Post: 22nd June 2008, 10:13 PM -
Where to get spot weld drill bit from?
By Com_VC in forum METALWORK FORUMReplies: 10Last Post: 24th January 2008, 07:53 PM -
Cast Iron vs Cast Alloy Wheels
By TerryG in forum BANDSAWSReplies: 4Last Post: 25th February 2003, 10:42 PM