Small Milling Machine and Accessories recommendation needed

[bbussey]

Carpet tape might work.  Too strong and it may destroy paint or decals.  I have used lighter, basic cellophane tape, but the cuts were truly light and the surface area at the tape joint was fairly large.

I use Permacel tape. The late Bob Fingerle of Anerican Limited advised me on the equipment and supplies. I ended up getting the same setup he had, as at the time I was planning on milling my own passenger car side molds out of brass stock to ALM's specs. Bob even made a pair of special cutters for me for milling the fluted sides. San Juan Car did the injection molding. But the car sides market collapsed before I perfected using the equipment, so now I use it in my modeling, where it comes in very handy.

[Sokramiketes]

I use Permacel tape. The late Bob Fingerle of Anerican Limited advised me on the equipment and supplies. I ended up getting the same setup he had, as at the time I was planning on milling my own passenger car side molds out of brass stock to ALM's specs. Bob even made a pair of special cutters for me for milling the fluted sides. San Juan Car did the injection molding. But the car sides market collapsed before I perfected using the equipment, so now I use it in my modeling, where it comes in very handy.

I think it turned into Nitto Tape in 2009 when they bought Permacel.  In any case: https://www.amazon.com/Nitto-Permacel-Double-Coated-Kraft/dp/B000QDL9GK

[bbussey]

I think it turned into Nitto Tape in 2009 when they bought Permacel.  In any case: https://www.amazon.com/Nitto-Permacel-Double-Coated-Kraft/dp/B000QDL9GK

Quite possible and not surprising.  I've had my supply since before 2009.

[cgw]

Sherline mill is the way to go.   My set up is a 2000 mill with a micro kinetics cnc retrofit.   I have had it for several years and it is perfect for N scale and other use around the house.  go slow on the depth and feed and it cuts like a champ. Cnc is a nice feature to have but is not necessary for the casual frame modification.   The CNC software that i use in micro kinetic mill master pro and vector cut 2D. Parts are readily available and there are a wealth of resources on line and locally.    The best advice I can give you is do not skimp on the end mills.  Cheap end mills  are available on eBay and amazon. The metal quality is very poor and they either wear out/dull  prematurely or shatter if you feed to fast. 

Quick question for Bryan,  What do the cutters look like for cutting the car side flutes? Are they just a micro ball mill?     

[bbussey]

Cutters for milling passenger car flutes in a brass or hard wax cavity mold actually are available now commercially at a reasonable price from Harvey Tool and other cutter manufacturers. They are called tapered rib cutters, with a ball point. Harvey offers them in multiple degree angles, up to 15 degrees.

[narrowminded]

Harvey Tools makes an unbelievable variety of specialty cutters as well as standard.  A little pricey but fair and very good, consistent quality plus virtually the whole EXTENSIVE cutter catalog is available from stock.  Also USA made.  You have to buy through a distributor but usually ships from factory.  You can check them online.

[jdcolombo]

Just to bring this conversation to a close, I decided on the Proxxon mini (micro?) mill. In addition to the recommendations and analysis of Narrowminded (backed up by a bunch of reading I did on proper milling speeds for small - 1/8" and less - milling bits), I considered the space I had and what I would be doing (mostly milling N-scale diesel frames). I got the mill on Friday, milled my first frame with excellent results yesterday (Saturday) and also used the mill to sand down the insides of a old shell using a 1/4" Dremel sanding drum and a 150-grit band. It all worked exactly as I had hoped, although I still need to practice. The mill is a perfect size for this work, and in fact I now realize that one of the larger R8 mills really would have been way too big for what I wanted.

The other great thing I learned about the Proxxon is that it is a widely-used mill by hobbyists, and as a result you can get reasonably-priced kits to convert the mill to CNC. While I don't want to do this just yet, the CNC conversion option is very attractive, particularly because one of the things folks have used it for is to cut custom circuit boards. I hadn't even considered this as a possibility, but it certainly may be useful in the future.

There are certainly a LOT of things this mill couldn't do - I'm not sure it would even be a good choice for milling HO-scale frames, for example. But for N-scale stuff, it's perfect.

Could a small lathe be in my future???

John C.

[wazzou]

I had read some reviews claiming adjustment issues from the factory and horrible noise.
What has your experience been and what other items did you purchase?

[peteski]

Just to bring this conversation to a close, I decided on the Proxxon mini (micro?) mill. In addition to the recommendations and analysis of Narrowminded (backed up by a bunch of reading I did on proper milling speeds for small - 1/8" and less - milling bits), I

John,
I'm a Sherline owner since the 1980s and I wouldn't swap it for any other machine.  I must also live in a hobby vacuum because I didn't even know Proxxon made lathes or mills!  I own some Proxxon hobby power-tools but I would not trade my Sherline for a Proxxon.

EDIT:  That didn't quite sound right. I probably never heard of Proxxon mill and lathe because (owning both Sherlines already) I didn't really look for alternatives.  The Proxxon tools do I own (The Mini Table Saw and X-Y Table were purchased from Micro-Mark and are identified as Micro-Mark brand (not Proxxon).

[jdcolombo]

Hi Bryan.

No horrible noise.  It's actually quieter than my Dremel when just running.  There's a bit of cutting whine, obviously, when you start milling, but it is MUCH quieter in cutting than trying to use a cutter in a Dremel or a cut-off wheel in a Dremel.

There are no adjustment issues that are any different from setting up a "big" milling machine.  You attach the table with four hex bolts, and there is a bit of play, so you need to make sure the table is square with the head block before locking down the bolts.  The gibs for the table were adjusted well with no play in the table itself (but see next paragraph); I saw no need to do anything with them.

The one issue I've seen so far is that if you are moving the Y axis with the outer roller arm on the wheel (instead of turning the wheel itself), the table does have some "jiggle" to it.  It's hard to describe - it's the whole table moving as you rotate the wheel using the roller arm.  If you turn the wheel instead, that goes away.  I'm going to investigate that further (it may be a case of the gibs being a bit too tight and creating too much drag), but I think it's just a matter of a small aluminum (light weight) table getting overpowered by a human being twirling the arm at the end of the long axis.  However, this is one area where a stepper-motor for a CNC setup would take care of the problem - or just a motor on the Y axis and controlled with a manual control box would also work.  For milling frames, the little wiggle produced by turning the roller arm isn't a big deal, but if I were doing something that needed high precision, I'd have to turn the wheel itself, not the roller arm sticking out of the wheel.  The X-axis wheel doesn't have this problem, but that's probably just because it's not trying to move the table lengthways.  Again, I think this is all just a byproduct of the fact that this thing is SMALL - so you just don't have the heft in the table you'd have with a 150-lb R-8 mini-mill.

Everything else seems to work precisely as advertised.  At some point, I'll get a small dial gauge to test the trueness of the movement in all planes, but right now I'm not doing anything that calls for that kind of precision, and I don't expect to be any time soon.

As for accessories: I ordered the 3-mill set (1mm, 2mm, 3mm).  I used the 3mm mill on my projects and it worked fine; I have some additional 1/8" mills coming from McMaster-Carr tomorrow, but I think the 1/8" size is what I'll be using 90% of the time.   I also ordered the vise, and there was a slight problem with that: they sent mounting bolts that had a hex key head.  But the way the bolts mounted in the vise, you couldn't get to the head of the bolt to put in a hex key to tighten the bolt to the table.  So I ended up going to Lowe's and getting a couple of short M6 bolts with standard hex heads, and used the 10mm wrench that comes with the mill to tighten them to install the vise.  The vise itself is very nice - it's small, but nicely machined and works great for holding my diesel frames (I used a small piece of 1/8" masonite on the front and back side of the frame to protect it from the jaws and create a flat surface for holding in the vise).  I also ordered the 3-jaw drill bit chuck to hold drills up to 1/8", but I haven't used that yet.

Overall, I'm very happy with it for what I wanted a mill to do.  If you needed something to do some machining that needed extremely close tolerances (e.g., .01mm or .001 inch), then probably you should go with one of the larger mills or at least consider converting this one to CNC.  A CNC kit costs about $400, so you could set this mill up for CNC for about $800, which is less than a larger mini-mill would cost by itself.  I think the key to a decent purchase decision is to be brutally honest about what you're going to use a mill for.  If you're doing small modeling or jewelry work, this one is great.  If you're in HO or O scale, or need to occasionally cut parts for the engine block of your '57 Chevy, this isn't going to do it.  The Sherline would be a much better choice IF you have available space and are doing any project that is larger than maybe 3" x 5" rectangle.

John C.

[narrowminded]

You may have to set up those gibs a little.  Do it with the vise tightened in place.  There will be a slight bit of drag when they are tight enough.  Not excessive but if it's free running there will be play as you described.  And gripping the wheel instead of the crank is probably better as you have better control for a smooth feed.  For those times when you need a close tolerance take a finish cut of only about .002" - .005".  I have very good success holding .001" that way when it's needed.  Also, take the finish pass as a climbing cut if you can and a smooth feed.  Not necessarily slow but smoothly dialed.  You can also go right back through without changing dials, taking what's called a "spring" pass.

If you're not familiar with that reference to climbing, do a search and I'm sure you'll find a reference that will explain why that works.  If you think through how a cutter engages the part as it's cutting you may see it for yourself.  It lets the cutter be a cutter and not a burnisher... then cutter... then burnisher... and that action shows up in the finish as well as is a little tough on the cutter edge.  Don't take heavy cuts that way as you're begging to spit a part and/ or break a cutter if it bites in and kicks but it's excellent for finish passes.  Also, don't be hard on yourself if this is your first crack at running a machine tool.  It takes a little practice.  Get some scrap aluminum and practice taking some different cuts and holding some decent tolerance.  Slow it down, speed it up, see what happens.  Heavier feed, lighter feed.  Depth of cut roughing then finishing.  You may surprise yourself.

[Chris333]

If it makes swarf, run it 

[jdcolombo]

Narrowminded was correct.  I played around with the gibs on the Y and X axes, and tightened things up to the point where there is no play at all in the table, even using the crank instead of the wheel.  I didn't realize how a tiny bit of adjustment to the gibs has such a profound effect on table play.  I still have a lot to learn about this milling stuff . . .

John C.

[wazzou]

That's one of the reasons I asked about that is that was one of the chief concerns that I read from reviewers about the machine. 
I'm glad to hear that it works as expected when all tightened up.

[narrowminded]

I read the Proxxon reviews before to buy and the theme was either, 1) it works good, 2) it is too loose and noisy, 3) it won't cut my (choose model) gun barrel.  What was evident for the most part when folks had troubles was that they really weren't very experienced in machine tool operation and then purchased the wrong machine for their intended use OR didn't know how to use/ set up what they did buy.  Understanding what the reviews said, tempered with my understanding the requirements of my needs machining model train parts, as well as decades of experience in machining large and small parts in my design and build business, I purchased the Proxxon as I described it and for the reasons outlined, very small parts using very small cutters, in a spare room in the house and stored in a closet, and machining mostly non ferrous metal or plastic.  For this application rigidity is not very important, high speed spindle IS very important.  As my review started, if you are going to be using 1/4" and up cutters, the iron machine with an R-8 spindle would be the better choice.  That's not what I was doing nor is it the normal need encountered doing most small scale model machining and I chose accordingly.  I hope it helped some folks.