HBM Questions for Viewers
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- เผยแพร่เมื่อ 14 พ.ย. 2022
- After posting my last update on the HBM I thought about the soft ways and whether they are in good shape or not. I took some measurements and I am asking viewers who have knowledge of machine tool alignments and such things what they think of the condition of the ways.
Enjoyed
I think your way of thinking makes perfect sense.
Unfortunately I'm not a machine rebuilder, so I can't help you with this.
You are asking all the right questions and I wish I could help.
At this point with what you have measured is seems probable that the ways are straight within makers tolerance. There should be no wear on the non master side of the ways, perhaps comparing this over the length may be an indicator. John, Australia.
Hello John. I like your idea of comparing the side of the master to the side of the non master way. I could check that with an inside micrometer. Thanks, Ken
@@hmw-ms3tx Ken is good that you read my comment and you like the idea. That was the way of measuring I was thinking of. Combine that with width measures of the non master side and you will hopefully get a complete guestimate of where things are at. Cheers from John.
Kieth Rucker just did some measurements on his HBM. Maybe some of that would help. You could also put a large parallel between the two box ways with a precision level on top, move it along the box ways, and you should be able to see how much it differs or even use some shims to relevel the bubble and the shim stack would tell you if the two ways are parallel with each other. Just an idea - I have no experience doing this.
I would agree that the ways have very little wear, either from being rebuilt or not used much. One thing that I might look for is layers of paint, or if some electronic components look way newer than the rest. Are you going to check the bearing surface on the rotary table? that is something you can use as a spindle or a surface to sweep on with an indicator.
Hello Kyle. This machine is a bit odd. The ways appear to be in excellent shape yet there are other indications that it saw heavy use. For example, the spindle bore taper is heavily fretted which would indicate heavy use. There are several layers of paint on the machine and there are a lot of cosmetic dings all over the machine (these usually accumulate during a long life of steady use). I am going to strip the rotary table down and clean and (if necessary) repair it. I like your idea of mounting an indicator to the table and sweeping it over the ways. At a minimum it would let me know if the table axis is square to the ways. Thanks, Ken
At least those ways look good . The underside is a common reference point that is used when reconditioning as it has the least amount of wear ( except for my one ! ) My JFMT lathe is a bit similar , some bits with no wear & some the complete opposite . 👍
I suspect my machine saw a lot of hard use and then was sent out to have the ways redone. It probably saw little use after that. The spindle taper is heavily fretted which would indicate heavy usage. In contrast to this is my horizontal milling machine. It is of the same era (early 1970's, just like me) and the scraping is worn off most of the slides but the 50 taper spindle bore is in excellent condition. Since posting this video I found my missing 10 power glass and had a look at the ways under magnification. The scraping marks appear to be on top of the small wear marks that run parallel to the ways. I think that would indicate a rescrape. After being turned off by what I found in the gear boxes I am starting to feel good about this machine again. I can fix almost anything on the machine except worn out ways. Ken
@@hmw-ms3tx Ways are hard to deal with , esp large ones . I have that challenge ahead of me next year on my HBM !
@@swanvalleymachineshop Are you planning on scraping them? In one of your recent videos I think you said you were going to take a scraping class. I'm looking forward to see how that turns out. If it goes well it gives me hope that I may be able to tune up the ways on my large lathe. They are the very definition of worn out. Ken
For a 50 year old machine it is very good, my 90 year old lather cut tapered as it is very worn so I just take a bit more time.
I agree, it does appear to be in good shape for it's age. I have a 60 year old lathe that is so worn you can measure the wear on the bed with a ruler. Thanks, Ken
From here, it looks good. I'm not sure if you'd call that flaking, though. I'm told there are many styles but usually its some kind of half-moon and the marks can vary in depth depending on the application. From across the internet, it looks like 20+ points/sqin scraping. Flaking for oil retention is supposed to be better on the downward facing side to avoid fouling but I don't know if this rule was followed by everyone. Someone mentioned a level, which might be the only practical way to check the straightness of the top surface.
how does z and y axis ways look like?
Hello Harri. I haven't measured them yet but they are hardened and ground and the finish on them looks excellent. I suspect they are in good shape as well. Thanks, Ken
I have a 60” camelback and other scraping gear, in Wpg, and might be able to help. Let me know if interested.
I don't think the top of your ways would have flaking on them .That looks like it has been scraped in the flaking would be on the top side so chips won't get in them
Do you think the bed has been re-ground and flaked rather than scraped and flaked ?
If so you perhaps could have more confidence in the straightness
Hello Steve. From what I can see it doesn't appear that these ways were ever ground. One thing that gives me confidence in the straightness (that I thought of after I posted this video), is that from the little I know about scraping it is likely much more difficult to scrape two surfaces parallel to each other than it is to scrape one surface flat (straight). If whoever worked on this was able to maintain the level of parallelism that I'm measuring they likely had no problem getting the ways flat(straight). Thanks, Ken
Normally on most HBMs those ways would be hardened and ground. That's odd they are flaked.
Have you used a trammel to check across the ways?
Two things.
1. I believe you have a machine that was hardly used.
2. I also believe you are reading way to much from what you are seeing.
A few years ago I bought a lathe from the government. I was positive it was going to be clapped out. It was quite the opposite. It was close to brand new. It just happened to go into service at the same time as a new cnc machine did. They only used it for quick things and the such.
You could have one of those situations on your hands.
Hello Captain McFingal. As I mentioned to another commenter above this is an odd machine. The ways appear to be in excellent shape but the machine has obviously seen heavy use. The spindle bore taper is severely fretted, indicating long hard usage and there are many layers of (post factory) paint on it. I suspect that at some point someone had the ways redone and then used the machine very little after that. If this is the case then I will be a happy man as most other problems can be corrected by me for a reasonable cost. Having the ways redone is very expensive and would require the machine to be shipped at least a thousand miles each way. Machines like your lathe are the holy grail of used machines. Old enough to be well built but still in new condition. Thanks, Ken
@@hmw-ms3tx From the run out you described in your video, I say you scored well.
Hello,
Your logic sounds good to be but I am no expert... "Jan Sverre Haugjord" TH-cam channel may be of interest to you and if you email Jan he is always very helpful.
Take care.
Paul,,