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  • rkepler
    replied
    Originally posted by J Tiers
    Will that be an expensive lesson? or will I find it is no problem?
    It's not a problem. Just start like you're testing the edge of the scraper and you'll find the right angle pretty fast.

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  • J Tiers
    replied
    Originally posted by MuellerNick
    You'll find out how to at the first cut.


    Nick
    Will that be an expensive lesson? or will I find it is no problem?

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  • oldtiffie
    replied
    Matched vee-blocks?

    Why can't it be done on a T&C or universal grinder magnetic chuck with the quill clamped both in the tail-stock and a good pair of matched vee-blocks?

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  • MuellerNick
    Guest replied
    Maybe TOO easy?
    You'll find out how to at the first cut.


    Nick

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  • beckley23
    replied
    Garlock Multifil 426 is Teflon impregnated with bronze, that is etched on one for the adhesive. It is available in sheet form in several thicknesses. Whatever you do, DO NOT use this stuff on the slides of a tailstock. I made that mistake many years ago.

    Here is a nice write up by Russ Kepler on Moglice;
    http://www.practicalmachinist.com/vb...moglice-98625/

    I did a little checling in MTR tady about the final alignments of the carriage and tailstock, Sections 26.55 and 26.65. The slides are scraped.
    Harry

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  • J Tiers
    replied
    Well, Nick, I understand your point.....

    if you scrape, but also replace the lost height with Moglice, etc, then you can avoid the hassles of bringing other parts into alignment with the new carriage position. You bring the carriage back where it was instead.

    Excellent for the carriage after the bed is scraped...... Might be possible to bring the carriage back to original height?

    And, it will likely be easier to scrape that material than the iron. Maybe TOO easy? I've never worked with it, and it sounds like one might easily go too far. Especially someone who normally scrapes iron only.

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  • MuellerNick
    Guest replied
    Both containers come like that?
    Yes. The catalyst comes in a tiny Al-bottle, the resin in a plastic cylinder shaped thing (I don't know the word).
    The resin's container is sealed with a tin foil. But that doesn't harm, it doesn't get bad with the screw on top alone.

    We should do some horse-trading Nick
    I don't think that will save that much. Add 19% VAT + s&h to me and shipping from me to you.


    Nick

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  • lazlo
    replied
    Originally posted by MuellerNick
    No. Here, Moglice comes in a little barrel with a screw on lid (or how you would say.).
    Both containers come like that? The Moglice I get from Devit, the catalyst comes in that little screw-top tub, but the resin itself comes in the pull-top (non-resealable) container.

    I tried pouring out half of each component (by weight) into screw-top containers, and it was a mess.

    50 g cost 11 €
    50 g sounds few, but it makes a lot way. I never bought bigger quantities from them
    That's a lot cheaper than we pay! 22€ for 100g = $28 USD. We should do some horse-trading Nick. You wanted some Dapra Canode, right?

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  • MuellerNick
    Guest replied
    I think that's intentional.
    No. Here, Moglice comes in a little barrel with a screw on lid (or how you would say.).
    50 g cost 11 €
    50 g sounds few, but it makes a lot way. I never bought bigger quantities from them.


    Nick

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  • lazlo
    replied
    Originally posted by lakeside53
    What does Moglice (and the other products) cost, and where do you get it in the USA?
    It's $40 for 100g of the old graphite-based Moglice (FL/P), and $47 for 90g of the Teflon-based Moglice. Problem is, Devitt tacks-on a $25 hazmat fee, so shipping is as much as the Moglice is.

    Last time I bought Moglice from Devitt, I called UPS with the tracking number and asked how much it cost Devitt to ship it, and there was no hazmat fee

    It's literally 2-part epoxy loaded with graphite or teflon -- absolutely nothing hazardous (you don't pay hazmat for shipping Devcon).

    Edit: the other aggravation with Diamant/Moglice is that they package the resin in a tennis-ball pull-top container, so you have to use all of it in one shot. I think that's intentional.

    Devitt is the only US distributor, and you have to order by phone: 877-368-1528
    Last edited by lazlo; 09-09-2010, 11:24 AM.

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  • lakeside53
    replied
    There is some great information in this thread.

    What does Moglice (and the other products) cost, and where do you get it in the USA?

    Leave a comment:


  • MuellerNick
    Guest replied
    Maybe Nick has an opinion?
    The difference is, that Harry suggest using a resin for the carriage.
    You can align the carriage with setscrews or leaving small islands that you file/scrape/shim to get the alignment of the complete carriage (incl. cross feed).
    So this breaks the rule "Work from bottom to top" but gets extra credits on the rule "Save time by thinking".

    Moglice (etc.) is very easy and quick to scrape by hand and a Biax would be simply the wrong tool. If you did your casting right, you only need minor or no adjustments and often enough you are done after scraping over the surface for oil pockets and cutting a groove for the oil.


    Nick

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  • J Tiers
    replied
    I sure don't do it for a living...... I'd starve.

    But I am "lazy", and prefer the way that is not as complex.

    I'm good with doing it either way. Doing the slideways may be somewhat better, more correct, but too much work for me! I think the result in your example would be the same either way, so I take the easier way.

    Maybe Nick has an opinion? He obviously is oriented to the most correct method. I respect both your opinions. And of course Forrest.

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  • beckley23
    replied
    While I don't recondition for a living, which I've always found to be a losing proposition, I do use these machines to make my living. You could say I have a vested interest in the accuracy and condition of my equipment.
    The reality of the carriage is thus; By the time these lathes hit my door there is a good deal of wear in the slides. In order to avoid relocating the gearbox and the right end bracket, the cross slide ways are the first things that gets finished. A few measurements are taken and the decision is made to apply Multifil 426 Way Strip Bearing material, very similar to Turcite, to build height, such that the gearbox and bracket don't have to be relocated. The carriage is than set upside down on the mill, and enough material is taken off the slides to allow for the epoxy, Multifil, and scraping stock. The scraped flat cross slide ways are used as a reference surface for the machine work. After the epoxy has cured, the Multifil is scraped, again the cross slide ways are used as the control surfaces. A level is used on the flat cross slide ways, and the cross slide is indicated against a parallel in the 4 Jaw chuck for that alignment. This is all shown in both threads I linked to earlier. Multifil, and I suspect Turcite, are far easier to scrape than cast iron. I won't use a BIAX on it. Imagine scraping butter with a dull knife, only a little more difficult.
    I have used these methods on quite a few lathes. There are only 3 lathes that I owned, a 6" Atlas, a 9" SB and a 13" Harrison, that the cross slides were scraped using your method, and only because I was touching up the ways. You're right the effect on the cross feed screw is minimal.
    Perhaps our differences are a matter of perspective, and stem from the initial condition of the machine, and what has to be done to achieve our goals. You can rest assured that I don't like doing any more work than what's necessary, as far as scraping is concerned.
    Harry

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  • J Tiers
    replied
    You seem to be opposite to me in everything... presumably that makes me "wrong"......

    As to why?

    Because, as I mentioned, it is two simple surfaces, to scrape to a limited number of constraints, and , if I understand your statement of the problem, the ONLY issue is the horizontal "aim" of the slide, which is "off" towards either the T/S or the H/S.

    If so, you probably do not need to do anything to the horizontal slideway, at least not for any alignment correction, just the dovetails. So any issue with the screw can be a left-right issue, and is probably very slight. Of course it could be a problem, but I am assuming the error is not huge.....

    Otherwise, by attacking the slideways, you may change the alignment of the carriage apron to the leadscrew, both horizontally and vertically, you may tilt the carriage and thus the compound so that it does not track parallel to the spindle when set at 90 deg, etc, etc. Of course that is also a small correction, but the longer length of the slideways means the actual metal removal is more than with the direct correction.

    If it is big enough to affect the crosslide screw, it will be bigger if corrected at the slideways, I think, so the apron will be affected. And the V angle ensures that there is a vertical component to the issue....affecting those other things.

    And for the privilege of possibly opening those cans of worms, you get to scrape at least 3 long surfaces to at least 4 constraints (flatness, overall angular positioning (the correction), V angle, relation of V to flat and vice-versa).

    honestly, it looks like less time and trouble to correct directly. I am looking at it as a business, not as one's personal machine, which of course is not costed the same way. I assume that one would like not to lose money on the job, while also getting a good result to keep the reputation.

    You asked... that is my answer.

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