Thread: Cross slide scraping

Originally Posted by jhovel

I get it! I think I know what happened on the fruit cake visit (with dovetail slide in his back pocket - or in an innocuous non-plastic shopping bag).... and the oil in the surface grinder was still warm..... and Phil said "just put it on the magnet while you are here"..... voila, 2 thous just disappear in a blink....

How close am I?

Surely not? I'm horrified...... and a little disappointed.

I thought you were hard core Stuart!

Originally Posted by jhovel

How close am I?

You win. This is why you’re an elder statesmen Joe. That’s pretty much what happened. He did bring beer. But forgot to take the fruit cake.

Originally Posted by simonl

I thought you were hard core Stuart!

He still has much to do, that has to be the worst gib / jib I've ever seen.

Originally Posted by Anorak Bob

And where is Greg Q? I know he's flying long haul but he has to land at some stage.

BT

I saw him on Thursday. That plane has to run out of fuel eventually.

Phil.

Phil beat me to it Joe,(in my defense I was out in the cold getting some more pictures.)
Phil kindly offered to knock 0.003" off for me(I don't recall the exact numbers we came up with were). I hadn't even thought up until that point about working around the tee slot, I thought knocking it off would be easy. Since I got home I've also realised there would be more than twice the amount of metal to remove on that top side for the same depth.

Thanks again Phil, I think you saved me at least another day, more likely two.
Still I think I learnt a lot spending a day on the bottom, for starters I know just how little metal I am moving each cycle even when I think I'm really getting into it with body strokes.

I spotted the carriage four times, these are the best of the pictures. Its not as good as I have been hoping.
Wow it starts getting tough now. To do the flat ways I have to keep them level left/right and front back(which I'm not sure it is anyway...... what was it you were saying about planning RC?)

Stuart

p.s. best I can say at the minute is its less that 0.0015". shame its curve didnt match the crosssilde

Just to skip back a little(I found a half done post from early)
Hi John,
I really should get a shed pc for ideas like that. Hmm maybe the camera in tablet could come in handy. If not I have my coloscopes, its about time they started earning their space.

Though I'm starting to think trying to do more than just check the carraige on the lathe wouldnt get far. Cleaning up the scraping mess could be painful.

Stuart

Well, you may have taken the easy way out (or is that the smart way out- my old boss used to say "work smart AND hard") but it just proves nicely what Michael, Dave and I were saying about the help that forum members are willing to hand out.

Only one problem, aren't you the guinea pig? What are those of us without access to surface grinders going to do?

I was just watching Nick Muller's vid on cross slide scraping (thanks for the link Mark).....It seemed like it only took him 10 minuets......

Ewan

Hi Ewan,
lol Yes Nick Muller's does make it look easy.
Dont worry about your guinea pig, he has just been saved from 2 days of "repeat as necessary" there is still lots of work to so. After all not only an the the proud owner of (likely) the worse T&C grinder table Phil has seen, I can now add the worse Gib. I took the gib into to show Phil as I said to him "the pictures just don't do it justice"

Originally Posted by Stustoys

Still I think I learnt a lot spending a day on the bottom, for starters I know just how little metal I am moving each cycle even when I think I'm really getting into it with body strokes.

Don’ discount the work you put into it to make the bottom flat, had you brought it here or any where else with a 2 thou bend in it, I could have slapped it on a chuck and made it shinny. But as soon as you release the magnet, it will still have that bend in it.

Phil.

Hi Stuart,
Where are the pictures of this shinny top? I saw a surface rust spot on it in some earlier photo's, so it would be gone now.

One thing I noticed in the earlier photos was your lathe doesn't look like it had much work on the cross slide as there wasn't much wear, mine has bedded itself in together over the years, but at least yours will be strait after this. Are you starting up a cross slide service? I might send mine down to check over, LOL

Dave

Hi Stuart,

I've been snowed under with work projects (paying type that is )... so haven't been following the crossslide scraping project all that closely, from the little snippets I've seen it's looking the goods.

I'm going to have to get serious about scraping the T&C grinder pretty soon, it's building up a backlog of work that's not getting done at the moment.

The machine survey and planning the sequence of steps is the bit that's the hardest to get my head around.

Regards
Ray

Phil makes a good point

Dave I dont have a picture of the shiny top ATM, I'll get one tomorrow.
My hands seem to be able to rust just about anything.
I'm starting up a "get it flat enough to put it on a surface grinder service"

Been thinking about alignment, I was just going to check that the way was 90 deg to the spindle....... but I haven't really checked the spindle is parallel to the ways. Like I know its "close" but I cant recall how close...... damn deep rabbit hole for a beginner.. still as long as I am not making it worse I have to be making it better.

Stuart

Originally Posted by Machtool

Google tells me “Wells Injectivity” is some thing to do with the petro chemical industry, how much water they have to pump down the well, to push oil out. But some how that’s included in a surface plate inspection report.

Phil.

Hi Phil,

I'd be inclined put some of that down to translation difficulties, just the last few weeks, I've all but given up on communicating complex details by text with chinese companies, and I've taken to sending them pictures instead...

I wonder what it really was they were trying to put on the granite plate spec sheet?

The best google mis-translation I've come across was Swedish to English, "ratchet pawl" came back as "frozen asparagus wheel"

Regards
Ray

PS... Ok, I think I've got it, water absorption of granite ranges from 0.10% to 0.40% or in that general range, so I'm guessing that's what they were trying to say.. their granite water absorption rate is 0.13%.... . gotta love chinglish..

Phil,
In the first spec sheet, have you seen a plate spec sheet that wasn't 0.0 on diagonal corners?* I mean if you knock those two 0.0s out the whole plate is within 0.001mm

Stuart

*not that I have seen many spec sheets but thats how they have all been.

Originally Posted by Stustoys

Phil makes a good point

Dave I dont have a picture of the shiny top ATM, I'll get one tomorrow.
My hands seem to be able to rust just about anything.
I'm starting up a "get it flat enough to put it on a surface grinder service"

Been thinking about alignment, I was just going to check that the way was 90 deg to the spindle....... but I haven't really checked the spindle is parallel to the ways. Like I know its "close" but I cant recall how close...... damn deep rabbit hole for a beginner.. still as long as I am not making it worse I have to be making it better.

Stuart

Just remember it shouldn't be 90 degrees with the spindle, but face slightly concave. I think it's something like 0.02mm per 300mm or less, but never the other way as you know. If you aim for spot on and it goes concave slightly it will be in spec, LOL