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Hello. I have a lathe like this and i want to regrind ways. There is no machine shop in my area to do this. How can i do this myself ? What are the teqniques that exist to do this? The lathe ways is not very long about 1.2m but machine is heavy about 5 tons.
Look into hand scraping: a time consuming, low tech way to get them "perfect"
On a machine like this the ways will most likely be hardened which can only be GroundQuote:
Originally Posted by dbsharp
It's not likely you can do it without a large machine to put the lathe bed on, we used to use a large Bridge mill / planer with a grinding head added, so it does not have to be a special Grinding machine just a large bridge Mill Planer with enough travel, snip below are machine types that you can do this on by adding a Grinding head if it does not already have oneQuote:
Originally Posted by mrsa
Not even with carbide scraper on a biax power scraper? I see they list hardened ways under the heavy duty model but not the others. :confused:
No not even with a carbide scraper, which you would not want to use on a hardened bed, if he does get the bed Ground then he would be able to use a hand scraper to fit the saddle Etc.Quote:
Originally Posted by dbsharp
Not sure it's a great idea, but "scraping" a hardened way with a grinder is possible. Google "scraping hardened ways grinder". You will see how people have replaced a scraper with an angle grinder for hardened way. I honestly wouldn't recommend it for you right now -- scraping is tricky and using your lathe bed as your first project isn't a great idea. In addition, you will not benefit from the amazing amount of scraping content on the internet in the last five years, because you would be using an angle grinder.Quote:
Originally Posted by mrsa
Once you scraped a couple of small projects in the conventional way (small angle plate, etc.), then maybe you could take what you know and transfer that knowledge to grinding with and angle grinder. Don't forget that scraping is not just getting things flat, but getting them aligned precisely, as well.
Hope that is helpful. If you do grind them this way, please document some (maybe make a thread here about it). It really helps the community to see what does / doesn't work!
You are obvious are not a machinist, and don't under stand what is required, Scraping and Grinding are two very different things and a angle Grinder would never be suitable to Grind a Lathe Bed, you can find all kinds of things on the internet doing it in practice is a different storyQuote:
Originally Posted by ebrewste
You can't scrap a Hardened Lathe Bed, Precision Grinding is required
Calm those horses...I didn’t slap your baby. Here is a direct link to a YouTube link that pops up when you do the search I recommend, showing what I’m talking aboutQuote:
Originally Posted by mactec54
https://youtu.be/YXLk0mJOwJM
This is essentially scraping, but using a hand held grinder (right angle air grinder in this case) doing just what is done in conventional scraping, but
on hardened ways. You can see the bluing, the peaks, valleys, no overlapping scrape marks. The whole enchilada.
From your response, I can only assume you took me to say that an angle grinder is a surface grinder? Not sure what set you off.
"Angle Grinder" (wedge) you would not do this to any machine hardened or not hardened, that would end up as a terrible job which in the machine building industry would be called a hack job, don't be fooled into thinking that this is an alternative way someone would do thisQuote:
Originally Posted by ebrewste
I have done a lot of machine scraping rebuilding and scraping and a angle Grinder are 2 very different things, if you don't under stand the differences and don't want a slapping than don't post something that you don't know much about other than looking on the internet :)
We had a guy scrape a hardened bed on an old Mori SL65, he did a fantastic job actually, but took him a week to do 25 inches, and he was a master fitter. That machine still runs today, 15 years later. Either way, this is not a job for a beginner, and the V ways make it even tougher to do. Even if you did find someone to grind in your area, you still have to deal with gibs and saddle fitting.
The SL65 I have done them also and they are not what you would call Hardened ways, they are a little tougher than a regular cast iron bed but you can scrap them without any problemsQuote:
Originally Posted by underthetire
Agree most forget that everything else has to be refitted to the new surface, they are only about 1/3 of the way done with just the bed
Scraping lathe ways... good god! Not that's its not feasible (?!)... its just that it would take half year+ to get angles, flats and underlips to line up. That hourly rate/cost would add up to about the same of sending a lathe bed to Russia by boat (twice) to get it done professionally. Flattening is one thing, lining up is another! Best left to machine grinders (hardened or not, normally).
And 5T for a 1.2m bed lathe?? Are you 100% sure about that? that is a pretty heavy spindle motor and tailstock you got there.
Dblcheck that... I'd bet its roughly 2~2.5T max which is what your typical UPS truck can easily carry (if not in a rush lol)
Crate it up and send it out, you'll be pleased.
Hello again.
Machine actually is 6Tons 15kw spindle heavy duty machine.
The ways are new at both ends about 20cm under the chuck and 25cm where tailstock is because in this place never reached by saddle.
tailstock has different ways from saddle the are not worn.. can i use them as reference for grinding saddle ways ?
I have a huge granite surface plate 2.5m x 1.5m x 0.36m about 4T (bed from a mitutoyo cmm)
also i have linear ways that i can attach to granite...
and i can get moglice material to "copy" the flatness of surface plate on strip of granite 130cm x 6cm x 3cm
so i will have a precision 130cm x 6cm x 3cm that i can place on the ways and because ways are new at the ends i will see how much have worn but what can i do to fix them ?
I have an idea to put epoxy granite cover complete the ways and on top install hiwin type linear ways.. i will make flat the surface where linear ways will installed with granite surface plate..
Any ideas how can i use this surface plate to restore lathe ways ?