The Ship Model Forum

Good advice - in principle and if you have the space for it. :big_grin:

Industrial machines are usually floor-standing and not so easy to accomodate in an European house/appartment. Here in Europe the small industrial machines, as were used in the watchmaking and instrument making workshops, command high prices. Arboga-sized machines ([url]http://www.lathes.co.uk/arboga/index.html[/url]) are indeed quite cheap here too because they are too big for most amateurs and outdated in a professional context.

wefalck

You may be able to purchase a small industrial milling machine or drill-mill like an Arboga EM825 for less money than a new hobby machine.

Often, a larger machine can do very fine work, but a small machine cannot do larger work.

I was able to purchase a milling machine like this for a ridiculously low price because homes in the U.S. are typically not wired for three-phase power, and many businesses went with CNC machines long ago.

In fairness, buying a phase converter cost slightly more than the machine (!), I ended up well ahead for the type of work I do and there is no blaming substandard results on the machine!

It is certainly worth discussing this with a machinist, who also may be able to give you some good advice about machining techniques.

Certainly worth a beer! :joker:

Cheers Wefalk, going there now.

Andrew

Holding small cutters in the SHERLINE should not be an issue. The main spindle has a MT1 and there are either MT1 collets (down to 1 mm) or WW-collets (with an adaptor sleeve and special drawbar) available. The WW-collets are the same as in watchmaker lathes and go down to 0.3 mm.

Small (carbide) milling cutters typically have either 3 mm or more commonly 3.2 mm shafts. The ubiquitous burrs normally have a 2.4 mm shaft, but the ones sold by Dremel also have a 3.2 mm shaft. According to my experience there can be an issue with these burrs running concentric - they are designed for use in hand-held machines, where concentricity is not such an issue.

A problem in my experience can be the view on and illumination of small workpieces. The spindle head of the SHERLINE is quite big and you may have to be quite close to the table so that cutters can be chucked-up short in order to minimise runout. I have an antique machine of about the same size as the SHERLINE and I always find this a bit awkward, particularly when the machine sits on the workbench. raising the machine on a box or similar might improve this.

The old machine buying rule is to get one with twice the capacity you think you need :big_grin: The table travel should be length of biggest workpiece plus twice the diameter of the biggest cutter diameter you think you will be using.

BTW, you may find it useful to have a look at the machine tool section of my Web-page (below).

wefalck

[quote="wefalck"]In deciding what machine you want (and can afford) you should first know what kind of materials you want to machine, what the likely maximum size of part you would be working on, and what kind of operations you may need to perform.

The PROXXON MF70 is made from aluminium. Particularly the table and all dovetails are aluminium. This more or less excludes in my opinion steel as working material. The steel swarf is likely to damage the machine sooner or later. On the other hand SHERLINE machines are also made from (eloxated) aluminium and their manufacturers promote their use with steel. The eloxation toughens the surfaces.

The PROXXON MF70 is designed for the application of small high-speed milling cutters. The maximum capacity of the collets is 3.2 mm if I am correct. This limits you to largely the small carbide cutters that seem to be ubiquitous these days. Most HSS-cutters have a shaft of 6 mm or above. If you have a lathe, you could make yourself flycutters to either screw onto the milling spindle directly or to be held in a collet. This would allow you to face larger items. The maximum size that can be machined is in the order of a cigarette pack (I am not a smoker, so I hope my size guess is about right).

In its basic configuration the PROXXON MF70 has three axes, x, y, and z. There is small rotary table (without worm-drive though) that allows you to make simple dividing work. I don't think that PROXXON offers an angle bracket, but it could be fashioned easily and would allow to mount the rotary table in a vertical position, greatly expanding the machining options. With it you can mill facets onto round objects, drill into the circumference etc.

Another thing to remember is that you (have to) typically invest another 50 to 100% of the basic machine price into accessories and tools, such as a good milling vice (go for a small screwless one, rather than the PROXXON one), a rotary table, clamping devices and cutting tools.

wefalck[/quote]

Thanks Wefalck, clear and sensible advice. I had been thinking along the same lines myself.

I will not be looking to machine large pieces of steel, mainly brass, plexiglass, HIPS and resin (castings). I model in 1/72 scale so most pieces will not be too much larger than your "cigarette packaging size....." (But one of the fundamental laws of tool selection is that "I should have got the bigger one.....' :big_grin: )

Consequently I have been considering a Sherline as an alternative to the Proxxon. However I am concerned that for the fine work, when i need to use the very small cutters, that I will not be able to use them in the Sherline chuck - any comment or further advice?

Much appreciated.

Andrew

In deciding what machine you want (and can afford) you should first know what kind of materials you want to machine, what the likely maximum size of part you would be working on, and what kind of operations you may need to perform.

The PROXXON MF70 is made from aluminium. Particularly the table and all dovetails are aluminium. This more or less excludes in my opinion steel as working material. The steel swarf is likely to damage the machine sooner or later. On the other hand SHERLINE machines are also made from (eloxated) aluminium and their manufacturers promote their use with steel. The eloxation toughens the surfaces.

The PROXXON MF70 is designed for the application of small high-speed milling cutters. The maximum capacity of the collets is 3.2 mm if I am correct. This limits you to largely the small carbide cutters that seem to be ubiquitous these days. Most HSS-cutters have a shaft of 6 mm or above. If you have a lathe, you could make yourself flycutters to either screw onto the milling spindle directly or to be held in a collet. This would allow you to face larger items. The maximum size that can be machined is in the order of a cigarette pack (I am not a smoker, so I hope my size guess is about right).

In its basic configuration the PROXXON MF70 has three axes, x, y, and z. There is small rotary table (without worm-drive though) that allows you to make simple dividing work. I don't think that PROXXON offers an angle bracket, but it could be fashioned easily and would allow to mount the rotary table in a vertical position, greatly expanding the machining options. With it you can mill facets onto round objects, drill into the circumference etc.

Another thing to remember is that you (have to) typically invest another 50 to 100% of the basic machine price into accessories and tools, such as a good milling vice (go for a small screwless one, rather than the PROXXON one), a rotary table, clamping devices and cutting tools.

wefalck

Hi All,

I am thinking of investing in a mini milling machine. Does anyone have any experience with milling machines - I have been looking closely at the Proxxon MF 70.

Thank for the advice

Andrew