Thread: cast iron and memory

Originally Posted by cba_melbourne

The problem with warpage of cast iron is mostly during the first year after being cast.

Good luck if you beleive that.

Originally Posted by cba_melbourne

Disturbing one side of a table is not unlikely to have some effect on the flatness of the other side. Particularly if it is a precisely ground surface.

Your experience is a lot different to mine. In 30 years being around the slide grinding industry. I've never known any one to do anything other than a 4 face grind, top / botom, top / bottom. They spring as soon as you grind the face. I conducted a tour,of slide grinding 8- 9 guys, last year, they would attest to the fact.

I have that table in the shop right now. A Schublin no less, that had a 0.17mm bend in it. It must be 40 - 50 years old. That only has that bend in it because he pulled it apart a decade ago, and left the table sitting on two timber packers at each end. Those of us in the know, will stand a table on edge.

You are in Melbourne, I'm only in Thomastown. Its still in my shop, I still have to scrape the saddle to the table. Your welome to come and inspect it. The bend is really well documented, as the Schublin belongs to this Ford Engineer, too long a story to go into here, but he finite analized it. We spent the last 15 months trying to press the bend out. That actully worked within reason. We got it down to 0.07mm.There after we ground it out.

To give you a picture. The Monach bed R.C is working on cost $1,500 +GST for 8 facits, grinding. To put you in the picture, that pissy little table cost more in grind hours to flip / flop it. Have you been reading some of those International Forums? It really upsets me, how they think cast iron doesn't move.

Phil.

Hmmm, so is it a forgone conclusion that it will warp once i sink the tool in and release the stress?
This puts me in a bit of a dilemma. I need to add this clearance, otherwise the mill is no good for its intended purpose. At the same time, the project has gone way over budget and i simply cannot afford another $1500 to grind the slides.
i do know a guy with a surface grinder which may be able to do the table slides, but underneath for the Y would be a challenge.

I presume that if i were to drop it off at the heat treaters for stress relieving before milling i would need to grind it anyway?

Thanks for the offer phil, i will bear it in mind but Thomastown is a fair way from me.

I havent been reading any forums on the matter, but from my limited experience cast does tend to warp as you break the surface. After turning down camshafts ive had to get them straightened but was hoping the mill apron might be big enough to hold its own, so to speak.

Well, the deed is done and the top slides looked good with the straight edge. I will do some more checks once i get someone around to help my lift the bloody thing out of the car!

Which brings up the question, how does one accurately check such a thing? Obviously i cant put it on the mill and run the DTI over it without assembling it first...

Originally Posted by Machtool

Have you been reading some of those International Forums? It really upsets me, how they think cast iron doesn't move.

Heres another example, some freaking clown called R.C, on P.M, thinks his old cast iron might have moved.

OzEE rebuild - Page 6

Stop it I tell you now. Cast Iron doesn't move. It's gosple. Bro, you should re-lap your granite to that while you have a master.

Pulling my finger out, I'll send your grinder in the next few. (days, weeks, months)

PHIL.

Originally Posted by Machtool

Heres another example, some freaking clown called R.C, on P.M, thinks his old cast iron might have moved.

OzEE rebuild - Page 6

Stop it I tell you now. Cast Iron doesn't move. It's gosple. Bro, you should re-lap your granite to that while you have a master.

Pulling my finger out, I'll send your grinder in the next few. (days, weeks, months)

PHIL.

Just use the line I use when people ask me when the boat will be launched. I always tell them it'll be in the water before Christmas....

PDW

Originally Posted by Machtool

Heres another example, some freaking clown called R.C, on P.M, thinks his old cast iron might have moved.

OzEE rebuild - Page 6

Stop it I tell you now. Cast Iron doesn't move. It's gosple. Bro, you should re-lap your granite to that while you have a master.

Pulling my finger out, I'll send your grinder in the next few. (days, weeks, months)

PHIL.

I have been reading that thread... Damn he/she is a top person that RC99...

re: the grinder.... Rumour has it that there is a truck heading north with a load of furniture on it... I wonder if we could smuggle the grinder onto it, throw out any worthless things like bedding, cupboards, wardrobes etc to make room if necessary... I could then bail up the truck on the border and reclaim it.... Sounds like a good plan...

Originally Posted by Machtool

Good luck if you beleive that.
Your experience is a lot different to mine. In 30 years being around the slide grinding industry.................... Have you been reading some of those International Forums? It really upsets me, how they think cast iron doesn't move.
Phil.

Dear Phil, did you really read the message that you are replying to? That is what I did write:

Originally Posted by cba_melbourne

The problem with warpage of cast iron is mostly during the first year after being cast. But it is hard to predict what may or not happen in your case. Disturbing one side of a table is not unlikely to have some effect on the flatness of the other side. Particularly if it is a precisely ground surface. I would be careful and remove only as little material as absolutely necessary for whatever your purpose is. Chris

I think in the haste you did understand the opposite of what I was suggesting... Just trying to make sense, Chris