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  1. #21
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    Getting back to the subject, "How good does it have to be?" Look at all the worn out machines making good parts. I always say you can see a good machinist if he is making good parts on clapped out machines. When a machine builder is making a new machine, they follow the new machine spec's found in a Schlesinger book, ASME standards, JIS, etc.

    How Accurate Is Your Machining Center? |


    Modern Machine Shop
    .

    If you own a machine rebuilding company as I did we told our customers, "the machine will preform as good as or better then new" This was easy in my Dad's time as many of the machines were built during WW2, so they were built to last a short period of time, so the USA could win the war. Many of our readers on PM are new to rebuilding or some who come here for help. I say to them, How good do you need it? He is learning to scrape and his best with-out a skilled journeyman teaching him in person, with out the proper tools will not be able to get it as good as new, but will make it better then it was.

    We have many here I would consider "pro's" who can scrape and rebuild machines to new machine standards. Just think about it, a hobbyist buys a machine worn out of new machine spec's, but he is going to machine farm equipment needing repair. He doesn't need tenths precision. If they hold .001" they are will with-in the spec they need.

    A few years ago while teaching a class at Keith Ruckers shop in Tipton GA. He had a Leblond lathe with a hard bed. We checked it out and I believe it was worn .004" near the chuck. He decided he could live with it as he could file out any wear errors. He bought the machine for $2000.00 and if he took it apart and had the bed ground he figured he would spend $25,000.00 Even with a perfect rebuild a 1940's Leblond would sell for $5000.00 So that machine was good enough to him. So the point I am trying to make, is. If you buy a machine and your a hobbyist or even a Journeyman Machinist what do you Need to make the parts your making?

    You may have the skill level of Sip as he has been in the machining business for over 1/2 his life, like me. He knows his stuff and he can make perfect parts on a worn machine. I am sure he would prefer to have a new machine.

    This is a forum about rebuilding and scraping. I am writing to thousands and not a few here. I am trying to make a point, not start an argument with anyone. I wish more will be written about machine scraping and questions from legitimate members who need help, not some knucklehead with nothing to do but read and write here.

    I am hoping the experienced members would start new posts to teach the new rookie members even if they don't ask a question.. Pass on your knowledge before you drop dead.

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    Thank you for the knucklehead. At least capable of distinguishing between then and than

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  4. #23
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    Mechanola....I may not have perfect grammar, but I do have this...Scraping Class 2019 with Richard King - BIAX


    and this. KING WAY Scraping Classes (English) - YouTube

    Let's see your credentials and your class info on scraping. Or sign-up for an Austrian class and learn how. They have classes this fall in Austria.

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    Give it a rest...

  6. #25
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    Thank You Mark.

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    Quote Originally Posted by Mechanola View Post
    No, it’s for Richard King and the perfectionistic psychiatrist. Typical amateur error to overdo.
    Those are sort of fighting words. Do you not see that?
    Disrespect up front. Not always in agreement with Mr King on all stuff but respect.
    This guy is no some random internet idiot. I do not think him a perfectionist and the argument would be opposite.
    A good balance but a little rough and flighty IMO.
    Trash as wanted but this guy knows things that very few on the planet do. I can not understand basic fights over qualifications or name calling.

    Bob

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    Lets just stick to the original topic, it is a good discussion lets not let our prejudices get in the way of useful content.

    I seem to remember a comment made a few years ago supposedly a Russian proverb, "Perfection is the enemy of good enough..."

    We all get stuck in our own battle over just how perfect we need to be. Sometimes we need the opinion of an another person to help keep us on track with what our goal should really be. The nice thing is that perfection isnt a crime, just a temporary affliction.

    Hope everyone has a nice weekend.

    Charles

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    Name calling and general lack of civility aside, I find this to be a super relevant thread. During one of my past lives i had many engineers of all experience levels under my care. I used to tell them the most important question in engineering is "how do you know when you're done?" The topic of this thread is kind of like that. Invariably my customers wanted the best widget their money would buy and in some cases were reluctant to accept a product that was simply compliant with their requirements. This is very similar the topic of this thread. Most of us want the best machine we can get within the limits of our time talent and treasure. It's good to be reminded that there is a point when you need to call it done.

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    Thank You Charles and Marka.

    What Marka said, It sort of reminded me when we did some machines for Control Data years ago. We were rebuilding some Do-All Slicer Dicers that we rebuilt. The cut wafer bars with diamond wheels in the electronics field. Or they did, not sure anyone still uses them. They were also called a creep feed. Anywho, They wanted us to paint them Ivory White, I said why Ivory White? The fellow said I want my shop area to look like a laboratory. It to another week to do the job, he didn't care how much it cost. It was a pain and a year or so later, I was out there quoting on another job and saw the white machines. They were dirty and the foreman who wanted them white was gone, they fired him because he ordered the white machines. lol...

    Most production shops wanted a "rebuild" and not a Rebuild with paint job. I started to brush and roller paint the machines though after I delivered (I was the truck driver too, when you own the company you do everything) a W&S Turret Lathe and as they unloaded it the rigger called over the operator and he said "there that piece of (you know) S__t. I figure he saw the outside and not what was inside. He had a negative reaction.

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    To paint or not to paint is also an interesting question. One one hand, one could argue that when a machine is completely disassembled is the perfect time to re-paint it. I myself had this conversation with myself as i am in the (painfully slow) process of what i hope to be a proper functional restoration of a 1941 Monarch 16CY complete with a bed regrind. When i had the apron down to the bare casting it took all the will power i could muster to not strip the old paint and apply new paint and primer. However, the apron is just a small part of the machine and after consultation with my brother, a machinist who has operated professionally restored machines, i decided against it. His point was "they all leak and in a year the new paint will be peeling just like the old". Even if this was a bit of an exaggeration his point remains valid. It's a huge amount of work to strip the old paint and properly apply new and it doesn't make the machine perform any better. The machine will just get covered with oil, grime and swarf anyway. I decided to put my energy into proper cleaning and functional restoration. When complete, the machine will look just as gnarly as it did when i bought it but it will be clean, properly lubricated and, I hope, will be more accurate.

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    The rigger's reaction can go deeper.... "it's a piece of crap, so run it like yah stole it"..... can lead to a lack of maintenance, even lack of oil. Seen it happen.

    And folks who do not understand see a nice clean paint machine and think it works as well as the paint looks... The ebay "rusoleum rebuild" works on many, including purchasing agents.

    As for how good is good, it needs to meet customer requirements. That may mean that the scraping is better than the rest of the machine, feedscrews, etc, but if that is what is wanted/requested, it can be done. Seems silly, but like the white machines, you do what the customer wants.

    Some stuff on a mill is worth getting quite accurate, if you can... other things no. Very irritating if a mill has a tram error scraped-in.

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    I think this is a great topic, but none of the posts so far talk about some things that I always think about when evaluating a machine I'm about to buy, or one that is not performing satisfactorily. One is how well made it is, what would it be like if it was new, how well maintained is it. Some machines I have owned are so well designed that they retain their precision and accuracy for many decades, as long as the basics are attended to. In that case, I see my role as the factotum of the machine, replacing seals, keeping the oil level up, cleaning the machine, repairing the lube system, replacing bearings, scraping the surfaces that do wear. I think both my Monarch 10EE and my Deckel mill fall in this category, with the Deckel being the better of the two.

    Other machines have flaws that originated in the factory, and those flaws need to be corrected to get them to perform to the level desired. So I will do what is needed, and probably do it again from time to time, since it is hard to solve basic problems in one go. For example, I have a large Taiwanese horizontal bandsaw that has never cut a perpendicular surface in 40 years. It keeps running, and from time to time I get disgusted and fix something on it. The basic problem is the design (or lack of design) of the pivot, and the alignment of the pivot , wheel axes, blade guides and table. Its not hopeless, but it would be a major project to get it to perform the way I want it to and be easy to adjust when it gets out.. Easier by far to replace it with a machine that has a good design, but I continue to use it because even with its flaws, I can correct the poor cuts on other machines. But when I buy some metal stock cut by some vendor, the cuts are always good and perpendicular, so I ask, why can't my machine do that.

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    Quote Originally Posted by rimcanyon View Post
    I think this is a great topic, but none of the posts so far talk about some things that I always think about when evaluating a machine I'm about to buy, or one that is not performing satisfactorily. One is how well made it is, what would it be like if it was new, how well maintained is it. ...................
    The amount of work to be put in is really dependent on the basic goodness of the machine for most who operate commercial shops. And on the ability to get a replacement that is in new or good used condition instead.

    While rebuilding a small machine of limited quality (Benchmaster, or one of the not-to-be-named types, for instance) is possible, it would not pay to do it unless you can do it yourself, and have a reason to spend the time vs some more productive activity. It probably would not pay to do ANYTHING to such a machine, in reality.

    The goodness of the work in re-aligning it (the real intent of "scraping") would be similar, there is no good sense in going all-out on a machine that was never meant to hold that accuracy. But, if you do your own work, it is your option to do it to any degree of goodness that you want.

    I can see doing it to create a special machine or tool for a particular job, if there are not better options. Then it is really a tooling project, and will pay.

    A machine that does not perform as it should is similar. Most any that has an original defect will be one that isn't of good industrial quality to begin with, even if made perfectly, and the better choice is to surplus it off (junk it, sell it, whatever) and get one that just does what you want.

    If you have a machine that needs, and DOES justify, a rebuild, or rescrape, then there is every reason for that to be done to restore original performance if done at all. Might not be what actually gets done, but it would not be a waste of money or time to do, depending on your other options.

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    Quote Originally Posted by rimcanyon View Post
    For example, I have a large Taiwanese horizontal bandsaw that has never cut a perpendicular surface in 40 years. It keeps running, and from time to time I get disgusted and fix something on it. The basic problem is the design (or lack of design) of the pivot, and the alignment of the pivot , wheel axes, blade guides and table. Its not hopeless, but it would be a major project to get it to perform the way I want it to and be easy to adjust when it gets out.
    FWIW I have an American made saw that fit that description exactly. A Rockwell 9X16 I bought new about '79 or 80. I fiddled and adjusted endlessly to no end. I was determined to have it cut correctly and kept at it. I even stripped it and sent the bed out to be ground parallel to the pivot axle on a Blanchard because we could see the bed casting wasn't flat from one side of the main slot to the other, I was sure that would correct the blade traveling non-square to the bed also.(Never again, Rockwell. You had a name at one time.) Reassembled, same problem. (!!!) I finally figured out with the help of a cast iron angle plate and indicators that the rear hinge casting was misdrilled where it bolted to the swinging frame with 4 bolts, so the pivot wasn't square to the swing frame, and the blade was travelling in an arc (not a slant) in relation to the base. blocked up the frame, unbolted the hinge casting, milled slots to adjust it about 3/16", bolted it back together and haven't had to adjust it in 40 years except for when replacing guide bearings. It has cut a mile of barstock up to 9" dia and cuts square within .005. We've put new bearings and seals in the gearbox 5 times, and replaced the wormwheel 5 years ago, put several v belts on it and 2 coolant pumps. Moving the hinge a little might be all your saw needs.

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  22. #35
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    Quote Originally Posted by marka12161 View Post
    To paint or not to paint is also an interesting question.
    I used to get carried away with paint ... after you go to the trouble to make it work well, it should look nice too, yes ?

    But after a while I learned moderation. In use, machines get banged up and dirty. On the other hand, it makes the shop look better and fits a self-image of "doing a good job" better if the paint is at least okay.

    So I now think 'middle of the road' is a good approach. Kinda like Mr King's scraping, good enough to do what's needed and maybe a little more for good luck. Doesn't need to be new Porsche quality but we don't want the rusted-out hulk look, either.

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    Jerry put it better. He wrote this in another thread in here. I'm not the only one who thinks about repairing used machinery and how good does it have to be.. Many on PM try to encourage new people who read here and not always write negative things.

    06-27-2021, 09:54 AM#14JST's AvatarJST JST is online now
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    Short story is that restoring machines can be a hobby/business.

    One fact is that you really do need to balance the value and work. I basically WILL NOT scrape any machine I restore for hobby types. They will not pay for it, and it's a lot of work.

    How good?

    Well as per the above, for hobby sales, make it "work", and hopefully not be to bad. The alternative is a chicom machine that was worse when built, so..... no scraping for them.

    A machine to be sold as "better"? Well, I cannot find much of a market for the "better" used machine, so still no scraping for them... Not worth trying to sell that work. A few times someone has wanted it, and OK, then it can be done. Most don't like the price, a few were willing to pay up like gentlemen, and their work got done.

    So that leaves the alignment and scraping-in stuff for myself, for my own machines. I did do a not-so good machine, a Benchmaster mill. Probably is better than it ever came from the factory, but still not chasing tenths on that one, it's a mill.... and not a very good one, but it was the first mill on which I did (had to) a full ground-up restore, improvement, scraping and alignment job.

    Did it because I had the mill, and it needed either fixed or disposed of. Wish it had the 36" table, but not many of those around. It's done and in use. It really makes a difference in usability.

    Was it "worth it"? Well, I now have a $2500 machine I can get maybe $800 for (it has both H & V setups). But, I'm not trying to sell it, I'm using it.

    Kind of an "apprentice project", I guess. Good learning experience, not doing any more mills until I have a decent Biax.

    I don't advise anyone in the "gee scraping sound like fun" category to start on a mill. It's more work than those folks want to do.

    I have a Rivett 608 that I bought for a song, with all parts... dirtiest machine ever. Also worn, but not 'too" bad. That one is worth my best efforts, no matter that "plastikdreams" probably considers it a "shitbox". And it is getting my best efforts, which means it does not go fast. My problem, not anyone else's so I really don't care what anyone thinks. Both it and the Benchmaster are for use, not being a polished-up "hangar Queen".


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