Scraping Makino MCC2013 Column

[Jesse Vanvleet]

I wanted to share some content of the type of things we do on a daily basis pertaining to scraping and rebuilding. In this instance the customer had issues with the column leaning forward creating squareness issues in Z and Y, which happens to most of these large HBM's. Makino factory spec is 12 microns per meter and this machine was showing out about 45 MPM. The first step we had to do was level the X bedways to create a baseline for alignment checks and we got it to ~0 in the Z direction(no twist) and then about 5 micron overall in the X direction using electronic precision levels. The next step was to remove the almost unbelievable amount of covers Makino uses so we could get the column out the front of the machine and the overhead crane gave us about 3 inches of clearance to make for a nice pucker factor. We used i-beam stands to sit the column on and we ended up doing all of the prep and scraping overhead and never had to lay the column down. Doing it this way is what I believe is a major key to running a profitable job and reducing various costs to the customer i.e riggers, more disassembly and much more time between rubs. We ended up getting the Z bed level to the same specs of X before finally reassembling the machine. At the end of the scraping process the Z-Y squareness was down to 6 micron per meter and the X-Y squareness was 3 MPM. Spindle point was out 1 micron in the X direction over a 330mm tram. It all sounds simple when reading the process but I didn't include the hundreds of pounds of chip removal, dozens of metal splinters and hours of pressure washing parts but as they say, You'll have that on them big jobs.

 

[rklopp]

My arms hurt just thinking about scraping a standing column. Do you have some support for the tool?

 

[Richard King]

Can you take a few more photo's. Do you have a spec sheet you could attach too? You say you tramed 330 mm / 13".? Is that traming the spindle to the column?
I see your a pro? So am I. I normally leave the spindle pointing up .0008" in a meter, so as the machine wears it gets better.

I have scraped several Horizonal machines over the years and lay the column down and put it on 3 points. That's the way the factories do it as I have taught scraping classes inside several new machine factories in Taiwan, Germany and Turkey.. it would be easy to lay down with your crane. A lot easier to scrape in my opinion.

I'm just asking these question and observations so the other readers can learn

 

[Jesse Vanvleet]

My arms hurt just thinking about scraping a standing column. Do you have some support for the tool?

Haha it’s more physical that’s for sure, but no just my arms. The only perk is you get to lay down while at work .

 

[Jesse Vanvleet]

Can you take a few more photo's. Do you have a spec sheet you could attach too? You say you tramed 330 mm / 13".? Is that traming the spindle to the column?
I see your a pro? So am I. I normally leave the spindle pointing up .0008" in a meter, so as the machine wears it gets better.

I have scraped several Horizonal machines over the years and lay the column down and put it on 3 points. That's the way the factories do it as I have taught scraping classes inside several new machine factories in Taiwan, Germany and Turkey.. it would be easy to lay down with your crane. A lot easier to scrape in my opinion.

I'm just asking these question and observations so the other readers can learn

Mr. King thanks for the reply. We’re familiar with your methods from viewing much of your content online. But no we trammed the spindle to a square on the table basically just to get spindle point perpendicular to X table. The customer only wanted the column scraped to get the 2 squareness’ fixed due to their large square die’s being off. The head was pointing up out of spec after we squared the column but the customer was willing to let the issue go due to production. These Makinos actually point more upwards the more they wear due to their design. I’m sure we will end up doing the table and head at a later date when they have time. We completed this whole project in about 13 days. The reason we didn’t lay it down was due to the additional cost it would’ve accrued. I was doing scrape, rub, check and back on stands in under an hour. Flipping would’ve made the process to where we only got 2 runs per day. We had to share the crane with the rest of the shop as well all day.

 

[Richard King]

Mr. King thanks for the reply. We’re familiar with your methods from viewing much of your content online. But no we trammed the spindle to a square on the table basically just to get spindle point perpendicular to X table. The customer only wanted the column scraped to get the 2 squareness’ fixed due to their large square die’s being off. The head was pointing up out of spec after we squared the column but the customer was willing to let the issue go due to production. These Makinos actually point more upwards the more they wear due to their design. I’m sure we will end up doing the table and head at a later date when they have time. We completed this whole project in about 13 days. The reason we didn’t lay it down was due to the additional cost it would’ve accrued. I was doing scrape, rub, check and back on stands in under an hour. Flipping would’ve made the process to where we only got 2 runs per day. We had to share the crane with the rest of the shop as well all day.

That makes since. It helps when you explain things. I see you are new to our forum with 2 posts, there are several of us who rebuild machinery for a living and there are several member who scrape their own machinery. Did you hand scrape or power scrape? When I rebuild HMC's I scrape the column laying on it's back resting on 3-points, then match fitting the headstock to the column and tramming the spindle to the column as it lays on the floor. reaching the tram bar from the top of the head to the bottom. That's why i questioned the 13'' swing. Now we know you are traming a square on the table I get it. I have a few other things I would suggest when you do the next rebuild. As if the machine wears like a typical machine the saddle and table will be worn on the column side more then the opposite side. Thanks for sharing your rebuilding techniques.

 

[lucky7]

I copied an idea from Forrest Addy years ago and hang my Biax from an overhead support with a long spring tied to the rope. Esp if doing work on vertical ways. Takes so much stress off my arms. Not sure if a guy could rig up something like that for working under a part?

 

[Richard King]

Dapra used to sell a counter balance devise, no one ordered them and they discontinued the,

 

[metal-ica]

Thanks for this post. Very interesting to see what's involved with things like this.

Curious, what's the year of the machine and what does something like this cost?

 

[lucky7]

Dapra used to sell a counter balance devise, no one ordered them and they discontinued the,

Hmmm, had no idea there was a commercial version. Mine was free- just raided the scrap bin. My Scottish Grandmom would probably smile…

 

[ballen]

Jesse,

Thanks for the great post. Please post some photos if you have them. I'm impressed that you can get one scrape/clean/check/blue/rub cycle per hour on something that size, even with a hoist.

The first step we had to do was level the X bedways to create a baseline for alignment checks and we got it to ~0 in the Z direction(no twist) and then about 5 micron overall in the X direction using electronic precision levels.

I was curious, what kind of electronic precision levels are you using for this? I ask because I've been restoring and repairing older and newer Talyvel electronic levels, so was wondering if that's what you are using.

Cheers,
Bruce

 

[Tyrone Shoelaces]

An old pal of mine used to work for “ Asquith “ who made the enormous floor borers as well as the famous radial arm drills. He told me stories of scraping 30 ft plus tall columns in situ riding in a basket off the overhead crane !

In my experience most hor bore spindle frames develop a sag at the tail bracket end because of the way they are configured around the ways and the position of the counter balance chains.

I’m with Rich in that we used to swing trammel the spindle or facing slide back to the column. Get that right and then you can consider the swing trammel to your big square on the table. Being honest with you we swung to a big square on the long travel ways first and then worked our way up to the table top.

You can get everything right geometrically and still have out of squareness issues when you are milling, especially on older machines. Thermal expansion of the milling spindle.

Regards Tyrone

 

[Jesse Vanvleet]

I copied an idea from Forrest Addy years ago and hang my Biax from an overhead support with a long spring tied to the rope. Esp if doing work on vertical ways. Takes so much stress off my arms. Not sure if a guy could rig up something like that for working under a part?

I've never thought of that.. Good idea I might try it out, our philosophy on upside down days is to just eat your Wheaties.

 

[Jesse Vanvleet]

Jesse,

Thanks for the great post. Please post some photos if you have them. I'm impressed that you can get one scrape/clean/check/blue/rub cycle per hour on something that size, even with a hoist.


I was curious, what kind of electronic precision levels are you using for this? I ask because I've been restoring and repairing older and newer Talyvel electronic levels, so was wondering if that's what you are using.

Cheers,
Bruce

On this job we used the Federal 230 electronic level.