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bigal

Help! Can cast iron be soldered?

Got a great engine recently and the price was heavily discounted due to the broken cast iron piece that spans the cylinder assembly and the axle of the flywheel.

 I've always heard cast can't be soldered but some articles on the net say it can.

Photobucket
Photobucket

cast

Any suggestions?
tmuir

It can but with difficulty.

Here is an article about it.

http://www.brazing.com/techguide/procedures/cast_iron.asp

If the part is not subject to high temperatures or stresses you could try one of those 'liquid metal' glues.
Dampfzauberer

I think best would be glueing....
MooseMan

Soldering cast iron's hard, and it can go wrong very easily....I'd be tempted to pin and glue it. Drill holes into the break and insert some rod, reassemble and glue. Fiddly, but strong and permanent.

Alternatively, glue and then mount permanently on a rigid base.
IndianaRog

Al, since you live in the US, a VERY good form of epoxy I have used is called "JB Weld".  It is sold in auto parts stores and my local Walmart carries it.  The stuff is grey in color when mixed and dried and takes about 24 hours to fully set up...lots of working time to get it right.  The stuff will glue engine block cracks and a friend of mine successfully patched a hole in the oil pan of a Honda motorcycle.

I think the key would be exceedingly good cleaning of the cast iron before glueing, perhaps with an aggressive spray solvent like Gun Scrubber (sold in Walmarts).

If you have one side that will be concealed, a strip of steel as a brace could be glued on that side for extra support.  

If I cracked a cast iron engine, JB Weld would be my very first choice for repair...I think you would find it to be the answer vs. brazing.

cheers,
Rog
rangerssteamtoys

IndianaRog wrote:
Al, since you live in the US, a VERY good form of epoxy I have used is called "JB Weld".  It is sold in auto parts stores and my local Walmart carries it.  The stuff is grey in color when mixed and dried and takes about 24 hours to fully set up...lots of working time to get it right.  The stuff will glue engine block cracks and a friend of mine successfully patched a hole in the oil pan of a Honda motorcycle.

I think the key would be exceedingly good cleaning of the cast iron before glueing, perhaps with an aggressive spray solvent like Gun Scrubber (sold in Walmarts).

If you have one side that will be concealed, a strip of steel as a brace could be glued on that side for extra support.  


If I cracked a cast iron engine, JB Weld would be my very first choice for repair...I think you would find it to be the answer vs. brazing.

cheers,
Rog


JB weld is great stuff, I fixed my torch with it and my dad fixed his A/c on his car. Cast iron is hrd to solder but I'm sure it could be done if completley necessary
bigal

JB Weld sounds like a nice alternative.     I've soaked ends in acetone and metal is now a nice clean lite grey color.  Now off to the hardware store.  
Thanks Guys    
alan2525

Yep - JB Weld is good stuff, it's also available in the UK too, as already mentioned, make sure the surface is good and clean. I'd also suggest cutting a piece of steel flat and file it to fit underneath, you could then use the JB weld to affix that and really get quite a strong piece.

Some of the modern epoxies are actually pretty good stuff. Some cars like Lotus' are even glued together with it!
spatial_pan

I personally couldn't live with gluing metal together be it super glue, araldite or any other epoxy resin that claims to be liquid metal. Its glue with iron filings in it. Why dont you Braze it!
IndianaRog

spatial_pan wrote:
I personally couldn't live with gluing metal together


Not to worry...there are support groups that can help you get over this glue uncertainty!!!

The beauty of a product like JB Weld is that once cured, it can be sanded, drilled and even machined.  Brazing such a small spot would leave a "hump" of brazing material and be far more noticeable.  That toy engine frame is not a high stress situation requiring such strength so the glue would be more than adequate for bonding AND virtually invisible.

I watched a program on "How it's Made" TV show about modern glues and adhesives which are used extensively in auto production and elsewhere.  The even had a glue that could be applied underwater to wet metal pieces and instantly bond.  They had two hooks each with a 4 inch flat disk opposite the hooks...the disks were pressed together in a tank of water with a bead of one of these new glues in between.  A crane then lifted on hook while the other was attached to a large truck weighing thousands of pounds.
The narrator then finished his discussion standing beneath the truck suspended in air by the crane...with that glue being the only bonding material...put together wet and fast.

I think JB Weld will hold a toy steam engine cast frame for sure...I would even stand under it myself!!!!

Rog
spatial_pan

IndianaRog wrote:
spatial_pan wrote:
I personally couldn't live with gluing metal together


Not to worry...there are support groups that can help you get over this glue uncertainty!!!
Rog


Ach Rog I am in the engineering industry and... a craftsman. I'm not disputing the benefits of moderen paints and adhesives, and I'm sure they can make a boing 747 out of tesco carrier bags(read walmart us ) Its that personal thing about glu I have the same hang ups with pop rivits I mean would you repair a dint in a boiler with plastic padding even if it was 'as strong as real metal'.  

If the man brazes it he can file it and polish it and it will be what it is a broken casting repaired with good sound practice, I'm new to all this resto game and even I feel guilty about using moderen paints.

So its not uncertaintity hell why not make the whole engine out of plastic and that immitration brass, its just... well I haven't seen any evidence of isambard kingdon brunell running around with a tub liquid super duper metal stuff  when his bridges were a looking dodgy.

It just seems a cop out to me thats all
tmuir

I must admit I prefer to do things 'the hard way'.
I still like using handtools when doing woodwork even when a modern power tool will do it quicker, gives me more satisfaction.

I have taken a bit from the Japanese though and use Japanese wood saws and to sharpen my chisels uses Japanese water stones (modern synthetic ones though as natural ones are too expensive). I don't consider my chisels sharpened unless I have a mirror finish on the cutting edge and I can shave the hairs off my arm with it.
But saying all that I have never soldered cast iron and would be wary about making my first attempt on a rare part.
johnreid

If it is to be brazed, take it to a pro.
spatial_pan

tmuir wrote:
I must admit I prefer to do things 'the hard way'.
What are water stones? Seriously moderen engineerining has evolved as indiana so correctly says and I do in the course of my work use adhesives and sealents (again it irritates me using on a pump what is essentially the same stuff that mi mum seals her bathroom bog seat with instead of proper gasket material) its just when I joined this forum and I saw the craftsmenship of the members and in awe a great deal that when confronted with a problem use some wiz bang glue. I beleived the ethos was to replicate those standards of the era, Mr indiana is clearly experienced and has helped me but in the past. Stilldrillin explained to me in pm that we all have our own ideas and I agree we should respect others opinions and preferences, i would regard the adhesive answer the last resort not the first... but then I have destroyed mqany things in the past tryin to weld the unweldable
spatial_pan

johnreid wrote:
If it is to be brazed, take it to a pro.


typical John Reid...sex on the brain
alan2525

If I had to choose between a well done repair using JB Weld or a botched part with a crummy brazing job on it...

...i'd still say go for the JB Weld, unless you have experience brazing cast iron with oxy acetylene.
tmuir

spatial_pan wrote:
tmuir wrote:
I must admit I prefer to do things 'the hard way'.
What are water stones?


It is the traditional way Samurai swords were sharpened.
Basically in certain parts of Japan (and else where too) there were natural formed rocks that had abrasive particles suspended in a clay medium that had turned to rock. Ther stones were collected and dress flat and then soaked in water.
The swords were rubbed across them and it would remove small particles of the metal. This would mix with the abrasive particles in the stone and the clay and produce a slurry that would sharpen the swords. After the Samurai was outlawed the swords smiths turned to making woodwork tools and used the same processes they used to make swords. This is why traditional Japanese woodworking tools are considered the best there is due to them been basically made by people who used to by swordsmiths.

You can get waterstones down to 12000 grit (I use to 6000 grit) so used properly you can get a mirror finish on the cutting edge.
High quality diamond sharpening pads could probably produce as good a finish but I like my water stones.

This is a link to some
http://www.timbecon.com.au/products/waterstones-381_0.aspx
johnreid

We call them Whetstones over here.
Wallace

Aka spit stones. And yep, people use spit on them  

I always used them to sharpen woodworking chisels
Cedge

God and Roger both know, I'm no big fan of J B Weld, but there are a few and quite rare circumstances where I'd probably say its a viable option... distasteful, but definitely an option...LOL.

I know how to preheat the casting and braze it. I also have the tools to do so. However, assuming that one doesn't have both the knowledge or the tools, then J B Weld would be perfectly acceptable to repair such damage as what is shown in the photo.  

Guys... it's pretty easy to be a purist when you're equipped well enough to be a purist.  However, everyone isn't.  Don't go throwing a fellow collector under the bus for dealing with what just might be a Hobson's choice situation.

Glue it, if that is the only viable option you have and don't feel guilty.

Tony... ask the HMEM guys how many of them use Red Green or Black Loctite, where soldering or brazing aren't an option....(grin)

Steve
tmuir

johnreid wrote:
We call them Whetstones over here.


Whetstones are similar but not exactly the same as some whetstones can be used with oil, oil will ruin waterstones. Have a look at the wiki here to see the difference.

[url]http://en.wikipedia.org/wiki/Whetstone_(tool)[/url]
xlchainsaw

Cedge wrote:
God and Roger both know, I'm no big fan of J B Weld, but there are a few and quite rare circumstances where I'd probably say its a viable option... distasteful, but definitely an option...LOL.

I know how to preheat the casting and braze it. I also have the tools to do so. However, assuming that one doesn't have both the knowledge or the tools, then J B Weld would be perfectly acceptable to repair such damage as what is shown in the photo.  

Guys... it's pretty easy to be a purist when you're equipped well enough to be a purist.  However, everyone isn't.  Don't go throwing a fellow collector under the bus for dealing with what just might be a Hobson's choice situation.

Glue it, if that is the only viable option you have and don't feel guilty.

Tony... ask the HMEM guys how many of them use Red Green or Black Loctite, where soldering or brazing aren't an option....(grin)

Steve
i agree . unless you are above average (i know many boiler makers welders who shudder at welding cast iron) then welding is out! if the glue option doesnt work send it over to me and i will cast one out of aluminium for you.
spatial_pan

ok ok I made one throw away comment  about my preferences dont shoot me for that  I do accept that different people have different facilities and that can determine what procedures they adopt and I wasn't intending to be controversial. [i didn't however at any stage use the term 'some botch brazing job'] I'm not a purist and certainly not a perfectionist and I wouldn't want to line myself up for a fall later  

A little bit friendly discussion is healthy in a forum anyway.
tmuir

It's all good S_P.

That's what is good about a large forum, there will be many different approaches to the same problems and we all usually learn something new because of it.  
Cedge

Spatial
Sorry if it appeared I was taking you specifically to task. All I was pointing out is the when cats need skinning, there's a lot of factors in choosing the right skinning technique from among many. This forum has seen it share of dictatorial repair advise in the past, so an occasional reminder of just how little we liked it isn't a bad thing.

Steve
johnreid

I think that it also requires one to consider just what exactly is being repaired, is it a fairly common piece or is it a rare old German Engine from the early 20th century. A JB Weld repair migh be just what the Doctor ordered for a common piece but an ols and rare piece requires more thought.

I have seen JB Weld fail many times when subjected to certain conditions and I also have seen long term repairs made using it too.
bigal

Got JD Weld and put the pieces together tonite.
Have it clamped up and pieces appear to approximate quite well.
Will see what it looks like tomorrow.  
johnreid

Give it a good 24 hours before unclamping
bigal

I will John.
I think I will second the repair after this sets with  (yet to be found)  two small pieces of metal along side the rib on the back.
Will be very hard to see anything on the back side once mounted.
xlchainsaw

sounds good to me.
alan2525

When repairing or restoring something. It can be beneficial to chose a means of repair that can be undone. If it's a valuable piece it can be good to see the repairs, it shows a part of it's history and we aren't doing any untoward damage to the piece than cannot be rectified.
spatial_pan

Cedge wrote:
Spatial
Sorry if it appeared I was taking you specifically to task. All I was pointing out is the when cats need skinning, there's a lot of factors in choosing the right skinning technique from among many. This forum has seen it share of dictatorial repair advise in the past, so an occasional reminder of just how little we liked it isn't a bad thing.

Steve

Not at all thats fine, sometimes I have ideas and poo poo others and then do a complete turnaround some time later.

I was doing an electrical repair to a flow switch this morning and it was neccessery for me to 'pot' the circuitry into a small plastic box. I was using a proprietory brand fron RS components which to me looked and smelt like watery araldite and it was a bit of a mess.

I colleague came into the workshop and the first thing he said was "ya wanna use JB weld on that, its from the states"
I suspect a conspiracy going on here  
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