Mills

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Since we beat up the lathe thing pretty good...how about mills...Im doing the drill press with a sliding vise thing (learning some stuff) but now, that has wetted my appatitte for a real machine. Ive been watching on e-bay and have seen machines for 200 to 15,000. I am, as the lathe question stated, not looking to do commercial work, but my own projects and stuff for my buddy's (will work for beer) . Harbour freights got a fairly heavy one for around 800 but am always sceptical of any purchase from there...comments ?
Reply:I've eyeballed those 800 mills @ Harbour Flotsum, and if I was given one, I'd be hard pressed to not sell it for whatever I could get, and buy a real machine.One of the BIGGEST things with a mill is travel.  In that respect, mills are like welders.  You can always make a 1/4" cut on a #2 Brown & Sharp, but it's a lot of setup time to make a 24" cut on a Bridgeport.  I have an Atlas benchtop in my cellar, and it's a handy little machine, BUT most of what I mill gets done in the big machines.The ARMY web site I posted on the lathe discussion also has a lot of good information on mills, and I'd encourage reading that.Depending on geography, there are a lot of good machines available for cheap money.  A achine that will make a home shop guy happy for a lot of years is no longer cost effective in a production shop.Appreciation Gains You Recognition-
Reply:Franz, I checked out that website, and one of the locations is literally across the street from me..Of course they have nothing selling now...lol...Ill just keep watching e-bay and the swap sheet and putting the word out around..Hopefully I can stumble on to a sweet deal soon !!
Reply:Communication problem JohnCheck this web site.http://155.217.58.58/cgi-bin/atdl.dll/tc/9-524/toc.htmAppreciation Gains You Recognition-
Reply:John,There's some great deals on ebay currently.  One is in Syracuse, although it's 3ph, the guy emailed me the specs required to make it single phase.  Been spending loads of time on the home machining site and it seems like everyone is running those rotary coverters anyway. Check out the one in Syracuse - last check it was around $600 with 2 days to go.  I'd get it, but still too early in the learning process for me.Good luck and keep checking the classifieds for closing shops.  That is usually a great source.
Reply:Ive got a 220v electric motor that I salvaged from a large swing saw that came out of a pallet shop. My plan was to use that on a mill that had a 3 phase. Now that Ive gotten a little more educated, Ill have to treck out the shop and see what hp it is. Look back at the post re: phase converters. I believe there was some talk about them not being ideal. I also found a Bridgeport in Vt., about an hour from Albany..$425. with no bids. Just not sure if Im ready for the 5 hour treck to go pick it up..Im really not in a big hurry, and being close to Buffalo, Rochester and Erie Pa, Im hoping to find one close..Maby Franz will give me one of his !!!
Reply:I will agree with Franz in that size matters a LOT. That said, you can often do a job with a mill that seems to small.  To reiterate, large cuts take  setup, setup, setup. I would avoid the small far east imports unless you are willing to do a lot of work to make it usable-I am told some are ok, but I have seen several different versions of the $2000 and under-all needed lots of work from the crate.IFull size runs from the tabletop/school size Bridgeports (M-head, I think was the small head) on up. They are tremendously easy to find, fairly cheap. If you can find a shop that is upgrading and getting rid of the last manual mill, you might get it for the cost of moving. Recently let a 17" shaper go to the junkyard for lack of space. Spent months trying to get it a home. Ditto for the old J-head (which did find a home) when we upgraded a year ago. Auctions tend to be pricey.The only time to not go for size is for very small work: A big mill often has difficulty with very small parts. This only begins to matter if you are doing things like making watch parts.To give you an idea of new prices and machine capacities, we ended up with a Vectrax for about $15000 (MSC house brand) that is pretty fine-- did a 36" dia boiler head on it without needing to remount. This has a nominal travel of 14"X30". proper fixturing and planing helps. Made a LOT of chips with no major issues over the last year. It seems to be basicly a knockoff of a Lagoon.f you are looking for modelmaking size, the Sherline has a good rep. I have a friend that uses one with CNC option for production runs of circuit boards and small parts.
Reply:Ditto my lathe comments on power requirements.  HP on the small machines usually isn't much but decide whether you can change the motor to single phase if the 3-phase won't work in your application.  Rigidity is another key feature in a mill so look for heavy castings and bearings.  Also make sure it uses relatively easy to find collets like R8 or 5C. We had a big Acer that used EM40 tool holders, which are expensive and hard to find.  Our smaller Acer used R8's and was a good mill if it wasn't used in high production.  We wore it out in daily use over about an 8 year period.  Whatever you find, you won't want to try and mill with a Jacobs chuck.  Some older mill/drills have Morse tapers in the spindle, which are fine if the holders and/or cutters come with the machine.Make sure when you install it that you use a machinist's level and get it dead nuts from the beginning.  My mill got out of level due to the foundation settling and there was enough twist in the table to produce a 3-4 thou variation across a 10 inch cut.  May not seem like much but it made a difference on that job.I have a Bridgeport J-head that came out of a maintenance shop in a stamping facility.  It was used rarely because there were so many others on the production floor and still has the scraping marks on the ways plus there is only about 5-7 thou backlash on both X and Y screws so it doesn't have much wear.  It was made in 1963 but is completely adequate for me.  I have installed a power feed and plan to mount a digital read out in the near future.  Good luck on your hunt...H
Reply:Phase convertors DO work well, especially for someone who is not running production on a machine.  Bridgeport stopped making single phase machines 30 years ago, and switched to supplying machines to single phase customers with a static type convertor.One of my shops only has a single phase service, and we use a convertor there to drive a #2 B&S mill, and haven't encountered any problems yet.Also, given the reduction in cost of VFD units, those are an excelent way to go for a guy who only has single phase available.All of these phase conversion schemes are really bumming me out cause I went to a lot of trouble to get 3 phase at my place years ago, and used to be able to steal machines before convertors came along.Appreciation Gains You Recognition-
Reply:To you East Coasters out there,As far as used machine prices go I've been buying used equiment for several years now off of the east coast and having it shipped to wild, wonderful, no end-to-end shipping Wyoming. The New York state area serves me quite well with two outstanding dealers: Ronnie Cammarata up in Wappinger Falls and Andy Popky out on Long Island. I've had excellent service, quailty packaging and just plain lousy e-mail from both of these individuals from day one. Ran into both of these individuals as e-Bay sellers and quickly decided to cut eBay out of the equation. Your experiences and prices may not be the same as mine as Wyoming was never a tool or equipment Mecca by any means and finding any used equipment at any price here is nearly impossible. Toss me a line privately at rwebster at vcn dot com if you wish contact information for either of these two guys. Just remember what I said about their e-mails.
Reply:Sorry about the mis information..maby it was welders that do not run well on the phase converters...Franz..is there a big difference between rotory and static..which would you recomend for a mill ??
Reply:John pen,You will see a noticeable drop in performance when using a static converter over a rotary converter. Basically the static converters do nothing more than trick the 3-phase equiement into starting and than feed them single phase power from than on. Now that is a very general generalization, but truthful. A rotary converter will give you true 3-phase out the power end with little or no loss of power to your machine if it is matched correctly. If incorrectly sized to may have some problems with "plug reverse" situations. A VFD, variable frequency drive, is also another method of obtaining 3-phase current. If you have an older machine with step pulleys to provide speed changes you can also use a VFD...within reason...to provide variable speed without belt changing by means of varying the frequency one way or the other from the standard 60 hertz most American motors are rated for. Some motors like it, some don't...the 1 hp Bridgeport J-head I own seems to prefer it over the static converter I started out with. Static converters will work for most conversions, but only if you are willing to trade off power and efficiency for the cheapness of the converter. These days VFDs can be had to run most 2hp and under machines for about 2-3 times the price of a cheap static unit and less than the price of a "manufactured" rotary unit. The price differential starts to turn sour above 2 hp, but there are available VFDs out there for much larger machine ratings as well. Upside of rotaries are that they can be homebuilt rather cheaply with a wealth of knowledge and plans out there on the Internet. Don't let a 3-phase tag on a piece of equipment scare you away from a potential purchase. 3-phase power is easy enough to come by with converters and the price differential of a 3-phase machine is often quite attractive even with a converter or VFD tossed into the equation.