My new mill

Discussion on all milling machines vertical & horizontal, including but not limited to Bridgeports, Hardinge, South Bend, Clausing, Van Norman, including imports.

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Bill Shields
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Re: My new mill

Post by Bill Shields »

Spent many years lifting really large loads and was trained that lifting limits are generally a function of the 'eye' or 'lifting ring' and not the hole into which it is screwed....assuming that the hole size / threads were correctly calculated in the first place.

Professional riggers generally use a swivel that is designed to take off-center loads without snapping off...since single ring eyes are generally rates only for direct line loads

I personally like the idea of lots of slings around everything to limit the 'single point of failure' concept
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ctwo
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Re: My new mill

Post by ctwo »

We had three straps around the ram on my mill, just to get it up to the flatbed.

Really, the eye would fail before the thread? I'd expect a lifting eye and its threads to be so much stronger than those cast threads.
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Bill Shields
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Re: My new mill

Post by Bill Shields »

Yes..an eye loaded so that it is not coaxial with the threaded area can bend and /or snap off unless it has a SHOULDER on it to prevent such.

do a google search on LIFTING SWIVEL and /or SWIVEL EYE BOLTS

and if you have a RIGGING HANDBOOK...the Bible from which I learned rigging in the previous millennium.

https://www.energy.gov/sites/prod/files ... entals.pdf

You will see on page 21 how it begins to describe how LIFTING EYES should be used - note vectored loads and how you can get into SERIOUS TROUBLE if the load is not along the axis of the thread.

The LIFTING SWIVEL is a variant of the SHOULDERED EYEBOLT
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ctwo
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Re: My new mill

Post by ctwo »

I've learned all my rigging lessons the hard way, so this will be good.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...
RSG
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Re: My new mill

Post by RSG »

Thanks for the tips for the base guys! As for the position in the corner, it's the best I can do as my shop is so small. I'll have to deal with trying to get behind it should I need to.

Liveaboard - you need to see a pic of my shop while I am in full production, with mounds of swarf on the floor :lol:

All this talk of lifting from the eye has me thinking I might have gotten lucky! I thought it looked precarious but the machinery guy said that's how he lifts all his machinery. I would have preferred to sling the ram from both sides myself and from here on out I will do so regardless of what others say.

I reinstalled my power feed last night and thinking on getting one for the knee as well. Next up is a four axis DRO from DRO Pros.
Vision is not seeing things as they are, but as they will be.
pete
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Re: My new mill

Post by pete »

Just like ctwo I've learned all my rigging lessons the hard way as well and always wished the companys I've worked for would have put me through a proper rigging course. What they can't do in those courses is show you real world rigging failures that can and do happen right in front of you. Showing it on videos doesn't hammer home the lessons in quite the same way. But fortunately I've not had any major failures. I came close a few times, but I'd like to think I learned from those. I've seen the results of a few who got unlucky. I can't think of one where it ultimately wasn't the operators fault. And almost always because they didn't take enough time to be 100% sure of sucess. Even more fortunate there were no injurys or deaths. It doesn't take long being around large heavy lifts before you figure out luck should never be a part of any of it. If I wasn't comfortable then it got rerigged until I was. As Bill has pointed out it's a bit more complex than a lot of people realize. Yeah I've talked to guys where it's mentioned "oh this is how we do it all the time". Yep on suspect rigging methods you have to be lucky every single time. Until that one day when things don't go exactly as planned. I've always done it so that if one sling is thought to be enough then add at least two more. Lame excuses after the fact are a poor substitute for good planning.

After taking my mill apart to get it into the shop I'd say the ram dovetails are probably heavy enough to take the load. The thinness of the rams casting above the dovetails didn't inspire much confidence that it would take those same loads. I still can't see through or know exactly how well it's castings were done or bet on there not being any flaws in those castings. If I ever had to lift my whole mill as a complete machine? I wouldn't be comfortable at all about using that lifting eye as the only point. Your mill made it over the fence and into the shop RSG. So it was a sucess, and just maybe someone at some point might learn something from this thread.
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Bill Shields
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Re: My new mill

Post by Bill Shields »

You are going to have to be quite agile to wiggle in there to attach the DRO...giggle...
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RSG
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Re: My new mill

Post by RSG »

pete wrote: Wed Aug 15, 2018 4:00 pm I wouldn't be comfortable at all about using that lifting eye as the only point. Your mill made it over the fence and into the shop RSG. So it was a sucess, and just maybe someone at some point might learn something from this thread.
Yes, and one of those guys is me, trust me it will never happen again.
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RSG
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Re: My new mill

Post by RSG »

Bill Shields wrote: Wed Aug 15, 2018 4:11 pm You are going to have to be quite agile to wiggle in there to attach the DRO...giggle...
I'm young enough to take a few lumps on the back of the head while crawling around under the mill still, I'll survive :lol:
Vision is not seeing things as they are, but as they will be.
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ctwo
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Re: My new mill

Post by ctwo »

A good point on the dovetails. You can back them up with some wood.

The very end corner of one of mine got chipped off from the fork banging it. My neighbor had a small stand-up fork and he was operating it to get the mill from the driveway into the garage. He lowered the forks a couple inches and then bumped the lever, so the fork jumped up and smacked the corner of the dovetail. I was going to round both sides off, or just JB weld the piece back on. It's just a visual thing.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...
Mr Ron
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Re: My new mill

Post by Mr Ron »

I have spent most of my working life in shipyards and have observed heavy lifts (500 tons). I was an engineer and even had to design (yes design) rigging arrangements. Everything in a shipyard that has to do with rigging, has to be inspected and certified on a regular basis. I saw what happened in a private shipyard on the West coast when a crane operator over reached while picking up a load. The load didn't go anywhere, but the crane did, right off the pier and into the waters of Puget Sound. Rigging is serious business. I too would be very worried with that single point lift. When a rigger says "that's the way it's always been done", I think the guy is too lazy to do it the right way.
Mr.Ron from South Mississippi
RSG
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Re: My new mill

Post by RSG »

The Mill came with a lamp that had a 110v plug on it and when you plugged it in the light was so dim it wasn't worth having so I pulled it apart to look at it and when I took the cover off it had a transformer in it and a label that said 220V - 12V, 50 Watts. So it's actually rated for 220v. So I cut the plug off and test wired it to the main switch and it worked great!

Now, my question is - Can anyone tell me if it's ok to attach this to the main wires on the switch so it's powered up even when the mill isn't running?

Image


Thanks in advance.....
Vision is not seeing things as they are, but as they will be.
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