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  1. #21
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    Quote Originally Posted by dian View Post

    michigan, i might take you up on the offer concerning the wheel. a wheel in the 200mm size costs upwards of $100 locally anyway.

    (btw, you have to understand the business culture in switzerland. there are no tool shops, no automotive shops, you cant walk into a grind shop and talk to the owner, its all big companies making big business. thats what makes us so efficient, i guess.)
    Just curious, why can’t you order from foreign Sources IT, GR, UK? ( in general, at the moment things might be difficult)

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    1 QT: the scraping marks are visible almost everywhere from what i remember.
    2 QT: i was planning to touch up the chuck because i know there are a few high areas (5-10 mu),
    1. With scrap marks visible very likely the machine is still in very good condition
    2. 10 microns is not a big deal for much/most work, likely the close to you chuck area is still very good.
    *So, don’t mess with the machine or chuck until you confirm what is best. / except to keep proper oil and normal maintenance.

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  4. #23
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    My Rant….
    We bought a heat shrink at the big shop for tool cutter length set-up and the calibration screen was in microns…
    Tool lengths that many were originally in .015 or .032 back in the inch days and perfectly functionable were changed to microns…So the engineers reduced the tool length to a few microns .. We were shooting for 5 to 10 microns... JPS (just plain stupid. / big waste of time.

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    QT: in switzerland. there are no tool shops, no automotive shops, you cant walk into a grind shop and talk to the owner, its all big companies making big business. that's what makes us so efficient, i guess.)

    Then why do you have a grinder / shop..just for hobby work? Here in the USA I can walk into a number of 1 to 30 man shops. Big shops not without an invitation.

    Do you have any GI friends? US military guys? I could ship a box of wheel to a GI for a low cost.

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    no u.s. military in switzerland. but first i have to take off that wheel and check it out on the balancing stand. then get hold of some prehard to make some adapters. no idea if my supplier is in business now.

    and yes, in many european countries (and japan i believe) people go to work, come home and just consume what others have produced. they dont fix their cars, work on their house, not to mention doing gunsmithing or similar. some might call an electricial to change a light bulb. its more and more difficult to get screws, tools or materials, at least in smaller quantities. thats why i buy a lot on the net and also from britain and the u.s. most parts for my cars come from rockauto, summit etc. and even for my porsche 914 i get parts from venice beach. in eastern europe, britain and scandinavia (at least i have that impression) people are still more "universal" and self sufficient.

    btw, i would be a very good customer of mcmaster, but they dont do overseas business. their prices are about a third of what i pay here and the range of products is incredible.

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    You could make adapter of CRS and they would be good for the rest of your life.
    With being able to angle dress you can live with one adapter.
    Dress angles? it is goo to be at least able to dress a 45*. A 45* on a wheel makes a find bevel-the-corners for a quick and pretty part beveled corner.You can 458 the front and back of a wheel and still use that same wheel for normal grinding/what I call topping a part.
    So one can get along with just one adapter and one wheel.But the wheel should be one of multiple uses like a 46k or near that.

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    Dian if you need help getting something from McMaster just ask someone here. I'm sure there are plenty who would be willing to help out a like-minded individual. There are definitely fewer and fewer folks who repair and make their own stuff around here.

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    yes, to have a bevel on the wheel is handy. what i have done is just run the wheel hard against some 45° piece of steel. as i purchase stuff on an ongoing basis and in smallish quantities i wouldnt want to bother anybody with it.

    but the question about grinding the working surface parallel to the worn ways doesnt want to get off my mind. i have a large magnetic parallel, its almost the size of the chuck. so if i were to put this on the chuck and grind it in, it would mirror the "banana" ways. a long, flat part ( e.g. 15" long, 0.5" high) would get sucked down and come out flat. or is my thinking flawed?

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    Both surfaces when ground on the first surface will end up being the same shape as the ways, doesn't matter if the part pulls down or not - machine travel is machine travel. If you put a flat-scraped mag chuck on the machine rather than one ground in place on the machine, whatever geometric error the ways have will show up as a parallelism error in the part. Even with the bottom held perfectly flat, the machine and thus the work would still travel in an arc or whatever shape it has while grinding the top. When the chuck is ground in place on the machine, it has that error already ground into the top surface, so when you put your part on the chuck it will pull down into the same shape that is being ground on top, producing a parallel workpiece.

    Trouble arises with very thick workpieces that can't be pulled down tight against a non-flat magnet. Since wear on most grinders is usually pretty minor, this usually only happens on a massively worn out machine though. (Alternatively also when grinding with very low magnet force). In that case you can get double the geometric error present in the ways, as you grind an arc (or whatever shape) in the first surface then flip it and grind another in the second surface.

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    Agree, I saw a big G&L 96" or so SG that had been run for a long time with two chucks, the finished part was a convex surface low at both ends..Re scraping fixed he problem
    still with the Ops grinder with having scraping visible don't his machine has this problem.
    Yes mounting a true flat parallel would tell

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    dian ..
    there are endless good cheap suppliers in the eu.
    mail me at gcode dot fi at gmail dot com

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    Qt;[ i have a large magnetic parallel, its almost the size of the chuck.]
    if you set that parallel on a surface plate and found it to be less than 3 microns out of flat.
    Then set it on your chuck with the mag off and shimmed it to indicate to be near zero-zero at the ends with moving long travel..and found less that 3 microns belly or dish your ways are decent.
    Even 12 microns is about 1/2 a thousandth..
    likely one would not want the fresh ground chuck to be 1/2 thousandth off (concave-convex)but a lot of/some grinding work can be a half thousandth off and be in spec.

    Oh, do you have a good surface plate? You want a grade A or better for grinding.
    Here in the us one can get a grade A for a very low price, likely it is made in chine so shouls be able to get same in your country
    WoodRiver - Granite Surface Plate 6" x 18" x 2" A Grade

    shars.com - Surface Plates

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    If its a hydraulic feed grinder, is the waylube also hydraulic? If so, is it getting to much oil? There shouldn't be oil dripping off the ways, the table will float and that is bad. There should be just enough oil to keep the ways damp.

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  19. #34
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    Default That;s not the Switzerland I know and remember...

    Quote Originally Posted by dian View Post
    ...
    and yes, in many european countries (and japan i believe) people go to work, come home and just consume what others have produced. they dont fix their cars, work on their house, not to mention doing gunsmithing or similar. some might call an electricial to change a light bulb. its more and more difficult to get screws, tools or materials, at least in smaller quantities. thats why i buy a lot on the net and also from britain and the u.s. most parts for my cars come from rockauto, summit etc. and even for my porsche 914 i get parts from venice beach. in eastern europe, britain and scandinavia (at least i have that impression) people are still more "universal" and self sufficient.

    ...
    I lived in Basel from 1996 till 2000 and the only regrets I have is of not having profited of all what was available to me there.

    Big companies like Novartis, Roche, etc. have dedicated workshops for any of their employees to use for their personal projects (of course, after undergoing safety training and training on specific equipment). At least back then a "Hobbyraum" (a room, generally in the basement of a building, that could be used as workshop for somebody's hobbies) was something highly in demand and hard to come by. It took me over a year to find one I could rent and it was 20 minutes away from my apartment.
    I remember buying specific cuts and drops of various metals at a place on the other side of town, and shopping for various stuff at a few specialized stores. True, those businesses were not highly advertised and the best way to find them was to ask some technician or repairman.

    At least back then, the small-medium size machinery market was fairly active with ads on Fundgruebe (now on-line as Ricardo.ch, a sort of equivalent of Craig's List) and I have always been amazed about what many Swiss had in their basements, in terms of high precision machinery, tools, etc.
    A friend of mine, in Ticino built most of the furniture in his house at what now would be called a makerspace near Magadino. In that area there was also a shop with car lifts that you could rent by the hour, including the assistance of professional car mechanics to do small maintenance to your car, like changing oil, brakes, etc.

    And, another off-topic thing is that pretty much each canton had one or more distilleries, where anybody resident in that canton could bring their own mash and make their own boozes under professional guidance, of course paying the taxes on the final product.

    At the time I was more interested in old cameras (and repairing them) than in machinery. However, I remember going to a couple of machinery swap meets and regretting only not having much money and space. I believe that there is still a large swap meet dedicated to machining, tooling, etc. in Fribourg.

    Pretty much all the friends I still have there are busy with their own hobbies. Yes, because of regulations and insurance, I don't think anybody is allowed to tinker with the wiring of their house, unless he or she has an electrician license. Similarly, given how computerized are modern cars, also that activity is delegated mostly to authorized shops. But, that I'm aware of, there are still plenty of people tinkering with old cars and motorcycles, among many other things...

    I know that everything changes. But I'm rather skeptical that Switzerland has changed so radically.

    Paolo

  20. #35
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    paolo, your talking about the "golden" age. all places where you could get drops are long gone. virtually all suppliers have minimum charges of $200-$300 plus cutting, per item, packing and delivery charges. five years ago i bought some tool steel locally for about $500. i ended up paying $10 per pound. since then i mostly buy on german ebay and have it sent to a service address on the border. ricardo is useless, you have to pay by bank transfer and the prices asked are hilarious. what people do in the "hobbyraum" is to get busy with a model railroad or a model airplane, again consuming and not making anything. rarely would you find a lathe (proxxon). i could go on forever. my biggest problem are screws and other standart parts. if i need screws i need them now. no way. to order is several days and buy a box of usually 100 pieces. thats not only a finaciall problem, but if i had 100 pieces of every screw i would have to rent a warehouse. actually the same with oil. i know of one place willing to sell less than a 60l drum and its 20 miles away. there are no hardware, automotive, electronics, rubber/plastic, hydraulic, leather or whatever stores. there is even nowhere to get fabric (e.g. to make curtains or a shirt). i grew up and went to university in basle, btw.

    yes, i have 80 liters of hydraulc way oil feeding the ways and its not accurately adjustable. i turn it on from time to time but its usually off when grinding. i have a medium sized aa granite plate. the parallel i was talking about is wider and longer than the chuck and 1/2-1" high. its a little beat up and i was thinking to grind it in on the chuck to have a surface that follows the wear in the ways.

    hanermo, not sure what kind of supliers you have in mind, but you never get the kind of prices like in the states and almost nobody ships to switzerland, not even the online shops. it would be prohibitively expensive anyway. besides customs slap on a flat fee of about $25 on everything and you usually pay the sales tax twice.

  21. #36
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    I have not read all the threads,,,but if your grinding parts low in the middle, then your chuck is high in the middle and when you mag it down the part goes convex. you grind it and when you release the part it shows concave or low in the middle. Also you need to buy a spray mister or use a spray bottle to cool off the part when grinding. Another tip would be to put the small plate on 3 machinist jacks and surround the plate with blocks so the magnet does not pull it crooked. The Austrian Hosts of my classes grind all sorts of parts on 3 points. Here is their website..Maschratur - Schaben & Maschinenservice and .email. [email protected]


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