Subject: FAQ part 5 of 8

From: [email-masked] (Jim Kirkpatrick)
Date: 3 Oct 94 03:14:15 MDT

This is the FAQ for rec.crafts.metalworking.  It is in several pieces
to keep the overall size of each part below the limits imposed by
some news systems.  This is part 5 of 8.

Generally, units below are United States dollars, degrees Fahrenheit,
and all the other silly backwards units we Americans still use.  Sorry.

The questions being answered in part 1:

0.  Where is this FAQ kept, and where are archives of the newsgroup?
1.  The original rec.crafts.metalworking charter.
2.  The CLOCKS bitnet mailing list, and other related lists.
3.  What are some good books and/or video tapes on metalworking?
4.  Who makes good lathes/mills/etc?
5.  Where do I buy a machine?

The questions being answered in part 2:

6.  What are good magazines to subscribe to?
7.  Where might one take classes or get instruction?
8.  Where can I get raw material for my projects?
9.  Where can I get tools, drill bits, etc.?
10. What are some of the related professional/hobby associations?
11. How do I harden/temper metal?
12  How do I wire up this strange motor?
13. How do I deal with mail-order suppliers?
14. How to sharpen knives, chisels, and other tools?
15. Some safety reminders.

The questions being answered in part 3:

16. How do I drill round holes?
17. What's TIG and MIG?
18. MIG welding technique.
19. Which MIG welder should I buy?
20. Books on welding.
21. Soldering/brazing topics.

The questions being answered in part 4:

22. What are bolt grades?
23. What is XYZ made of?
24. How do I build a furnace or forge?
25. What is Damascus steel?
26. How do I repair/replace this old leather belt?

The questions being answered in part 5:

27. Can I use a drill press as a cheap vertical mill?
28. What is involved in building a steam engine?
29. How do I anodize aluminum?
30. Rust!  How do I deal with rust?

The questions being answered in part 6:

31. Are there any machinery museums?
32. How do I cut metal?
33. What kind of oil should I use on my lathe/mill?
34. What are the various tapers (Morse, JT, R8, etc.)?

The questions being answered in parts 7 and 8:

35. What is Electric Discharge Machining (EDM)?
99. Names and addresses of publishers and suppliers
    (OK, so I got tired of re-numbering it every time a new
    question was added!)

-------------------------------------------------------------------------------

27.  Can I use a drill press as a cheap vertical mill?

     Sometimes people want to use a drill press with an X/Y table attached
     as a cheap vertical mill.  Will this work?

     Generally, yes, but you should not do this.  The bearings in a drill
     press are not designed for side loads.  This may cause premature failure
     of the bearings, and may also cause significant sideways deflection
     and wandering (if you must do this, don't expect finish-quality cuts).
     If you extend the spindle down very far towards the work, the deflection
     could be quite severe.  Mill spindles are more stout than drill spindles.

     In some presses, the chuck is held in only by a taper.  Side pressure
     could cause the chuck to fall out.  Some milling tools are not designed
     to be held by a drill chuck, or if your spindle does have a taper, the
     taper will be wrong (mills usually use either a Morse or "R" taper
     while drills often use a Jacobs taper; check this out before buying
     any tools).

     An X/Y table often does not come with finely-marked dials, and may in
     fact be quite inaccurate.  For coarse cuts this may be OK.  Note too
     that a real mill will have controlled Z-axis feed, while on a drill
     press this too will be quite rough to control.

     As for how big a cut you can make, or how accurate your setup will be,
     there is no consensus.  You'll have to set it up and try it.  Considering
     the bearing/deflection problems, moderately light cuts would be
     recommended.

     Speculation:  use end mills, not fly cutters (or at least avoid fly
     cutters, or be careful).  Depending on the setup, a cutter may enter
     the work, then due to the deflection the cutter might be driven into
     the work farther, jam, and break itself or the work.  An end mill cuts
     more or less continuously and might not have the same problem.

     Paul Amaranth <[email-masked]> volunteered his experience:
       ---
       I have only machined soft materials (copper, plexiglass and other
       plastics).  I would not recommend using anything but very light cuts
       (if at all) in anything harder.

       As you would expect, I had a number of problems.  Fine vertical depth
       adjustments are difficult.  I set the quill stop at the desired depth
       and held it in place by hand.  You could move the table up, but most
       drill presses seem to use a fairly coarse rack and pinion for the table.

       I used an endmill, which worked fairly well.

       Any backlash in your x/y table will get you into a load of trouble.
       This may not be too serious if you're facing off a surface, but will
       cause lots of problems if you want to make slots or cutouts with any
       precision.  Backlash may also cause chatter.

       In summary: this works if it's absolutely the only way you can do it,
       you don't need a lot of precision and you're working with soft
       materials.  I got around these limitations by buying a real mill.
       ---
     Alternatives:  If you have a lathe, consider buying/making a milling
     attachment, if your work size and lathe will allow.  Consider buying
     an inexpensive mill/drill machine if you can't quite afford a mill.

     In general, some of the same comments apply to buying a mill/drill or
     other combined unit as opposed to a dedicated machine for each purpose.
     Mill/drill machines are not as rigid for milling as a pure milling
     machine, but may be the only alternative before the money runs out.
     Combinations seem to work adequately for many woodworking applications
     but metalworking generally requires a lot more force.

28.  What is involved in building a steam engine?

     NOTE: see also the FAQ entry in rec.railroad.models on live steam
     railroad modeling.

     (with thanks to Tim Kirby and Ian Kirby (no relation))

     The creation of working steam engines, be they stationary engines, road
     engines, marine or rail locomotives, is quite a common hobby throughout
     the world.  Many people who would like to get involved in such modelling
     are, however, frequently at a loss as to how to start.  What follows is a
     set of simple pointers to get you on board.

     - Magazines and Journals

      There are four (English language) magazines that specifically deal with
      this subject:
        "Model Engineer" and "Engineering in Miniature" from the UK
        "Modeltec" and "Live Steam" from the USA
        (they may be available from a local worthwhile model store;
        alternatively, check the FAQ book list for the publishers)

      Reading any of these magazines will quickly give a feel for the hobby.

     - Clubs and Associations

      They are all over the world.  Look through the magazines listed above for
      club addresses; most if not all of them have the names and addresses of
      clubs all over the world.  If you can't find a club remotely near you,
      here are a couple of suggestions:

       Try posting a request on the net!  It can be a remarkable resource.
       Try writing to the editor of one of the magazines.

     - Scales and sizes

      Stationary engines are most often tabletop sizes; they can be very
      decorative and interesting exercises in machining but are not often
      "used" once built.

      Marine engines are often built as decorative or "stationary" models,
      however you may also find some installed in model boats.  Some of the
      suppliers in the magazines listed above may provide more information
      about marine engines.

      Road locomotives are usually referred to purely by scale, most often
      somewhere in the range of 3/4" scale (3/4 inch to the foot) to 4" scale
      (4":1') A farm traction engine in 3/4" scale will probably be around 12"
      or 14" long - quite handleable by most people.  A 4" scale model is 1/3
      full size - big, heavy and arguably no longer "Model Engineering", at
      least with respect to the resources available to the average mortal.

      Rail locomotive scales can be a little more confusing because of a
      tendency to refer to them by the rail gauge that they run on.
      Unfortunately the gauges are not completely standardized for some scales
      (although one might expect that they would be.) The following table lists
      the most common "larger scales" and the gauge lines they run on (based on
      a nominal 4' 8.5" so-called standard (USA) gauge track):
 
      3/4" scale (0.75":1') =   3.5" gauge
      1" scale   (1.00":1') =   4.75" or 5" gauge
      1.5" scale (1.50":1') =   7.25" or 7.5" gauge

      There are 10.25" and 15" lines as well as smaller (2.5" gauge, Gauge 1)
      that are modelled in live steam.  Availability of land, track and
      facilities will often affect a builders choice of scale.  Note that the
      modelling of narrow or broad gauge models introduces another confusion
      factor - a 1.5":1' scale model of a prototype that ran on 3'6" gauge
      track in real life would result in a track gauge of 5.25".  This would
      commonly be adjusted to fit on a 5" or 4.75" gauge line.

     - It must cost a fortune and take forever

      Not necessarily.  There are many suppliers in this hobby who can provide
      as much or as little as you need, from a set of original blueprints for a
      prototype, through those who can provide scaled drawings of proven
      models, books giving detailed operation-by-operation procedures on how
      to create a model, sets of castings that need machining or even ready
      machined kits that can be assembled on a kitchen table... or they will
      sell you a complete, ready-to-run model.

      The amount of money spent will vary typically as a function of how big
      the model will be, how much work the builder does (as opposed to buying
      ready-built parts) and what resources the builder has in his/her 
      workshop.

      Needless to say, the amount of time spent building such a model will be a
      function of the same things.  As a rule of thumb, the more you do
      yourself, the cheaper it is and the longer it will take you.

      Reading the classified advertisements in the magazines listed you may be
      able to pick up a part-complete or secondhand model for less than the
      cost of the parts new (though you are at the mercy of the workmanship of
      the builder.  Let the buyer beware).

     - What about boilers?

      The subject of boilers is complex; each country has its own rules and
      regulations - which could never be justly covered here.  Some pointers,
      though:

      + If you build a 'published plan', there is probably a published boiler
        plan to go with it.  This usually means it is a proven design, which
        is *good*.

      + Steam clubs will have some sort of regular boiler inspection and test
        requirement.  Talk to the appointed boiler inspector at your club.

      + If you are in the slightest bit wary or unhappy about building a
        boiler, *get some help from someone who knows what they are doing*.
        Some companies will sell you "standard" boilers for published designs
        ready made; there are others who specialize in building custom boilers.

        You may be able to lower the cost by doing all the preparation work and
        getting someone else to (braze/weld/whatever) the bits together.

      + Remember... this is a pressure vessel full of very hot water and steam.
        You *really* do not want it to fail.  You will probably be closest to
        the boiler if it does...

     - What's a good book on the subject?

      There are many, many books available on this and associated subjects;
      some are general texts, some specialize in particular aspects.  A good
      place to start is (unsurprisingly) read through a couple of issues of
      the magazines mentioned; most of the publishers (Village Press, TEE,
      Argus) publish and/or sell a number of texts; writing to the publishers
      should elicit a list of currently available books.  Also try some of
      the suppliers catalogs found in the magazines; A.J. Reeves Ltd.,
      Power Model Supply and Coles Power models all carry books on general
      topics and specialist areas such as boilers, valve gear etc.

     - Do you have any other advice?

      Reading the magazines is all well and good, but try to find someone to
      talk to who has had some experience - this can not only save lots of
      frustration but can also lead to lots of very useful shortcuts and even
      material help.  It may mean finding and joining a club, which, if one is
      considering building a rail vehicle, at least means that there will be
      somewhere to run it when completed, without then having to build a track
      too!

      The first-time builder is strongly recommended to consider choosing a
      published *model* design (from one of the magazines or plan suppliers)
      where all the scaling is done, and the finished article will work if
      built according to the plans.  Converting full size prototype drawings
      to a working scale model is not recommended for the "normal" first-timer!
      As you might expect, the published plans cover some models suitable for
      the beginner and others best attempted by an experienced builder.  Again,
      we cannot recommend strongly enough getting advice from a club of some
      sort if you can find one.

      Ask the supplier if the design was ever serialized in any of the
      magazines and if the text is available, either as copies, back issues or
      as a published book - blow-by-blow instructions can be very reassuring,
      even if you know what you are doing in a machine shop.

      Choose wisely, so that interest is maintained.  In particular with rail
      models, you need some rail to run it on.  Unless you are fortunate enough
      to have plenty of land and money, you will probably want to run on a club
      track - find out what your local club has before you build or you may
      spend several years creating a beautiful working model with nowhere to
      run it.  If there are several gauges available at your track of choice,
      consider carefully which track you want to be able to run on.

29.   How do I anodize aluminum?

      (pieced together from various sources, including the newsgroup.  JK)

      First, this is only meant to apply to aluminum.  Other metals, such
      as titanium, niobium, and possibly magnesium and others, can also
      be anodized.

      Aluminum oxidizes very quickly, and rapidly forms an aluminum oxide
      coating that inhibits further oxidization.  This coating is useless
      as is, in terms of protecting the metal, because it is so thin.  A
      thicker coating can be produced by immersing the part in an
      electrolytic solution and passing an electrical current through it,
      similar to electroplating.  The resulting film is nearly colorless,
      and can be easily dyed because it is very porous at the molecular
      level.  Then, by placing the part in boiling water, the film's
      pores can be sealed; the oxide changes from one form to another
      as a result.

      To be more specific, parts should be very clean and grease-free.
      Commercial plants will first clean and etch the surface in a caustic
      solution, such as lye (sodium hydroxide), followed by a thorough
      wash.  The parts are placed in an acid solution, such as 15-25%
      sulphuric acid, and connected to the positive source of a power
      supply (use only aluminum hardware to make the connection; no
      copper in the solution!).  The part(s) comprise the anode, and the
      cathode is lead (lead sheet, or the whole tank might be lead).
      Appropriate current is applied, e.g. 1.5 amps per decimeter (3.4
      square inches).  This lasts 15-25 minutes if no dying is planned,
      or 45-60 minutes for dying.

      Dying is the next step, if desired.  Since the pores are extremely
      small, many common dyes will not work.  Some wool dyes are known
      to work, or you can purchase commercial anodizing dyes from an
      industrial supplier.  Typically this involves immersion in the
      dye solution, which may have to be heated to be effective.

      Sealing is then done by putting the part in boiling water, which
      changes the film from "gamma" aluminum oxide a hydrated form
      called boehmite.  Boil for about 20 minutes.

      Another anodizing process involves using chromic acid.  This is
      not suitable for alloys with more than 5% copper.  The film is
      thinner, but very durable.  The very thin film is also a benefit
      when very close tolerances must be maintained.  However, because
      chromic acid is a very nasty chemical, its use on an "amateur"
      basis is discouraged, and is commercial use may be closely regulated.

      Anodizing is sensitive to the type of alloy.  For example, alloys
      for die casting have a lot of silicon, which makes it pour and
      mold well, but it makes anodizing almost impossible.

      By all means, find a few references and read them carefully before
      attempting anodization.  If at all possible, try it out on scrap
      pieces before attempting it on your masterpiece.  Be sure to flush
      the part completely to remove remaining acid.
 
      An alternative is to use a commercial firm to do the anodizing.
      Some net folks report they can be a bit rough to deal with, as
      they may be more used to dealing with large jobs and may not
      appreciate a home machinist with a single 5-inch part.  Look
      in the phone book under anodizing, or [electro-]plating.

      Some have reported using a lye solution to treat the surface,
      which yields a fairly uniform "fuzzy" surface, that may be
      acceptable as a final surface without further treatment.  Don't
      use a strong solution or the aluminum will disappear too fast;
      do this in a well ventilated area, as hydrogen gas is emitted,
      stay away from flames/sparks, and remember that lye will eat
      people as well as aluminum!  The resulting surface can be dyed,
      or painted with a chromate primer.  (One tablespoon of lye per
      pint of water has been suggested).

      Another alternative is a product called Aluminum Black from
      Birchwood Casey, which is often advertised in model railroading
      magazines, and may also be available via gun stores (it is in the
      Brownells catalog).  Brownells also lists a nickel plating
      solution for aluminum, though it appears non-trivial to use.

      References:

        1.  There are two books mentioned earlier in this FAQ that
            deal with anodizing.
        2.  "Anodizing Aluminum in the Amateur Workshop", in Ham Radio
            Magazine, January 1979, pages 62-69, by David W. Hembling.
            Sadly, this magazine is out of business, but should be
            larger libraries, or available via inter-library loan.
            This article lists several other references, including
            addresses for dye makers.
        3.  "Passivating Aluminum Alloys" in 73 Magazine, September
            1965, pages 74-80, by Robert A. Kidder.
        4.  Some jewelry-making suppliers deal with anodizing.
        5.  The magazines Strictly IC and Model Engineer allegedly
            have discussed this, but I don't have exact references.
        6.  Argus Workshop Practice Series, number 11, by J Poyner.
            (see name/address section for Argus' address).
        7.  Sandoz Chemicals Corp supplies dyes for aluminum anodizing.
            Their phone number is (704) 372-0210.

30.   Rust!  How do I deal with rust?

     Some machinists live in areas where rust prevention is important, such
     as those in humid areas.  There are various steps to reduce the problem,
     and sometimes several steps need to be taken simultaneously.  Here are
     some ideas from previous posts on the topic:

     Doug White <[email-masked]> wrote, on 2 Jun 94:

     I have a lot of expensive tools/toys that I have a LOT of trouble keeping
     from rusting.  Over the years, I have tried many different tricks and 
     products, and I've summarized my results below.
 
     The paper is called VPI Paper (Vapor Phase Inhibitor), and it's available
     from Brownell's (address in FAQ), as are raw crystals.  You want to make 
     sure that the 'dusty' side of the paper faces the tool, and don't be 
     surprised if some plastics (vinyl tool pouches) end up with a funny white 
     surface.  It doesn't seem to hurt the plastic, but it's disconcerting
     until you get used to it.  The tools will stay rust free much longer if
     they are sealed in a tight box, or a zip lock bag.  In theory, you should
     replace the paper annually if it's exposed to the air on a semi-regular
     basis.

     There is also another similar product called Zrust.  This comes in a
     number of forms, typically plastic 'cartridges' and flat plastic squares.
     They are also available from Brownells, but if you think you are going to
     be using a lot of this stuff, you're better off locating a dealer and
     buying direct.  The cartridges can handle an entire tool box or cabinet,
     and the little squares are good for smaller containers.  Once again, the
     tools should be stored in some sort of container.  The more airtight it
     is, the less frequently you will need to replace the rust-inhibitor.

     A company called Hydrosorbent sells silica gel desiccant in several 
     convenient sizes.  The nice thing about these is that they have an 
     indicator to tell when they're saturated, and you can 'recharge' them in 
     the oven.  I use the small aluminum packs for some of my tools, and
     all of my target pistols.  There is a new company that makes the same
     sort of thing in a plastic case that you can recharge in the microwave.
     If anyone knows where to get these, I'd love to find out.

     I also use a dehumidifier in my basement.  I live near Boston, and in the
     summer when my basement is still cool, the relative humidity goes through
     the roof.  I have a 25' x 30' basement, and a 25 pint capacity
     dehumidifier can keep the RH down to around 50% without running
     continuously.  It's best if you have a drain, so you don't have to
     remember to empty the bucket all the time.  Mine costs me about $20/month
     in electricity for 3-4 months each year.  If you go looking for a
     dehumidifier, get one that has a freeze-up cutout, and a hose connection
     on the machine, not the tank.  This saves a lot of space, and gets the
     water source up higher for easy draining.  As it is, I have mine up on top
     of a small set of shelves so that it will drain into the laundry sink.
     Check Consumer Reports for the most efficient model you can get,  it will
     pay for itself in electricity in short order.

     Brownells also used to sell 'Gunsmith's Soap', which was supposed to 
     neutralize the pH of your skin before handling things.  They discontinued
     this before I could get a chance to try it, but I have found that washing
     your hands to remove salts from perspiration can help.  If anyone knows
     a source for 'Gunsmiths Soap', I'd love to try some.

     The one last trick I use when I'm handling something I don't want to rust
     (like when I'm disassembling a target pistol) is to wear cotton
     "inspection gloves" that have been lightly sprayed with a thin rust
     preventative oil.  This simultaneously prevents me from etching things
     with my corrosive perspiration, and lightly coats everything I touch with
     oil.  If you are concerned about what the oil does to your skin, you can
     wear latex gloves underneath the cotton.  It doesn't work well for really
     delicate work, and you have to be careful not to let anything slip
     through your fingers.

     There are several spray treatments that work well for storage.  My current
     favorite was developed by Boeing, and is called BoeShield T-9.  It's 
     available from many marine supply houses.  After the carrier evaporates, 
     it leaves a thin surface film that does an excellent job of protecting
     steel from corrosion.
     ==================================
     Doug White <[email-masked]> followed up on the above,
     on Fri, 3 Jun 1994, with these addresses:

     Hydosorbent Co.
     Box 437
     Ashley Falls, MA  01222
     (413) 229-2967

     Sells Silica Gel descant packages in the following sizes:
     750 gram aluminum canister, 6"H x 4"D, protects 57 cubic ft., $24
     360 gram carton, 2" x 4" x 5", protects 27 cubic ft., $10.75
     40 gram aluminum box, 4" x 2" x 1/2", protects 3 cubic ft., $5.95
     26 gram packets, 2 12" x 4", protects 2 cubic ft., $12.00/10

     All but the packets are re-chargeable in an oven.  Post-paid, but
     $2.00 shipping charge.  They take MC/VISA

     Northern Instruments Corp.
     Lake Industrial Park
     6680 N. Hwy. 49
     Lino Lakes, MN  55014
     (612) 784-1250

     These folks sell a variety of VPI products.  The two most useful ones
     are their Zerust Vapor Capsules and Plastabs.  The capsules are plastic
     and have and adhesive strip to stick them into tool chests, machine tool
     cabinets etc.  The Plastabs are small squares cut from a 1/16" yellow
     sheet.

     The capsules come in several sizes, and are rated by radius of
     protection, and lifetime:

     VC-1-1, 1' protection radius for 1 year
     VC-2-1, 2' protection radius for 1 year
     VC-2-2, 2' protection radius for 2 years
     VC-6-2, 6' protection radius for 2 years

     The only ones I have a price on is the VC-2-1, which were $5 each.  The
     protection life varies with the degree to which the container is sealed.
     The capsules have a label to mark when they were installed so you know
     when to replace them.  Considering the cost, you may be better off with
     the silica gel canisters.  They will need recharging more often, but have
     an indicator.

     I couldn't find any detailed literature on the Plastabs, but I bought a
     sack with over 500 1/2" squares for $60.  They are much easier to use
     than VPI paper for small tools and parts.  I just toss one or two into
     a zip lock bag of small tool case.  These are sold in the 3/4" size by
     Brownells as 'Rust-Blox' (see below), where they claim they are good 
     for 300 cubic inches.  Brownells wants $27.20 for 100, which is a good
     bit more expensive than buying them in bulk from the Zerust people.
     You'll need to call them to find a local distributor.  The shelf life 
     is probably limited, even well sealed in a plastic bag, so if you don't
     need a lot, Brownells may still be cheaper.

     Brownells Inc.
     200 S. Street
     Montezuma, IA  50171-9989
     (516) 623-5401

     This is a gunsmith supply house, and sells a lot of good tools and other
     gadgets that even non-gunsmiths can use.  They have an extensive range
     of rust preventing supplies.  They sell the Hydrosorbent canisters for
     slightly less than Hydrosorbent does, and they carry the VPI tablets in
     small (but more expensive) quantities than N. Instruments.  They also
     sell VPI paper and Cosmoline (THE original GI rust preventative grease).
     The paper comes in 12" sq sheets, and can protect 1 cubic ft. for 2 years
     MINIMUM.  Typically, it lasts much longer.  They carry half a dozen
     varieties of aerosol rust preventatives, greases etc.

     Stock #

     415-100-040   40 gram silica gel cartridge             $5.50
     415-100-360   360 gram silica gel carton	            $9.95
     415-100-750   750 gram silica gel canister	           $22.50
     084-058-050   50 Rust-Blox Vapor Tabs                 $15.70
     084-058-100   100 Rust-Blox Vapor Tabs                $27.20
     084-031-010   VPI Paper, 10 sheets, 12" x 12"          $4.20
     084-031-010   VPI Paper, 50 sheets, 12" x 12"         $14.88

     I think that exhausts everything I know about rust prevention.  I've
     been fighting the battle ever since I moved from New Mexico 24 years
     ago, and I hope this can save someone some trouble.

     Doug White
     MIT Lincoln Laboratory

     =====================================================

     If the parts are small enough for that treatment then you can use
     "Blue Bags".  They are made by Bianchi ostensibly to store handguns in,
     but I find that any rustable metal parts are protected by them. They
     have zip lock style tops and come in several sizes.  I believe they also
     sell some in rifle sizes but without the zip lock closure.

     =====================================================

     For rust removal, the most common suggestion was Naval Jelly by Duro,
     available at many hardware stores.  It contains dilute phosphoric
     acid as its main ingredient.  Be prepared to apply a proper preventive
     after removal, as the metal will be left in a vulnerable condition.