Buying advice sought re Milling Machines: e.g. Proxxon: FF230 vs. BFW40/E vs. MF70

It's only 4 screws holding the column of the sieg x1 to the base? Would it be too time consuming to separate into two halves to be put away?

Edited By Pete. on 31/03/2021 16:57:51

I fear the answer is no! It's a really tough requirement because the machine needs to be lightweight AND high-speed AND powerful AND able to handle milling stresses. The limited budget doesn't help either.

Might be more practical to meet the requirement with two different tools, a high-speed drill plus a small milling machine within the weight limit. Or to accept the compromise imposed on drilling by a slowish mill.

Using a drill as a mill isn't an option: trust me, everyone since Adam has wondered if might be OK! If drills worked as mills we'd all be doing it. Sadly, drills just aren't rigid enough to take milling forces. Poor results and dangerous to the operator.

Speed isn't the only criteria: the power / torque needed to cut metal is proportional to the area under the cut, so a 6mm drill needs about 9 times more power than a 1mm, which suggests trying to combine high-rpm drilling and low-rpm milling in one machine is mechanically tricky. For that reason a specialist high-speed drill for small diameters will work well with a dinky motor and modest bearings hopeless for milling. And the power and bearings of a milling machine don't favour high speed. High-speed and high power at the same time exist in CNC world, but are well outside the budget.

Although small drills like to be run at high-speed, they work fairly well at 2800rpm, so a mill might be good enough. It depends on what you're doing and how much of it. Cheap poorly ground drills perform badly at low speed, and low speed is always a problem drilling hard materials like PCBs.

May not be relevant, but the slow speed of a mill can be used to make holes much wider than 6mm in steel. Providing a hole big enough to take a boring bar can be made first, hole diameter is only limited by the size of the table.

If I knew of a good answer I'd share it. Perhaps someone else knows of a suitable machine?

Dave

Edited By SillyOldDuffer on 31/03/2021 17:09:25

Because of the hours you put in inserting little bits of packing to tram the head to the table....

John, I was going on the assumption it would be fit for purpose out the box, if it's not, we'll that's another topic on it's own.

Francis, the updated x1 sold by Arc has a fixed column.

Two points.

As far as I am aware either the Taig nor the Sherline mills have quills for drilling. Both rely on the Z-axis leadscrew for such motion, and that makes drilling on them a little tedious I suspect. That's one reason I bought an SX1LP rather than a Taig (I have a Taig lathe) or Sherline mill.

If most of the work you want to do is small scale and milling is more important than drilling, have you thought about a small lathe with a vertical slide. I have done small scale milling on my Taig lathe before getting the SX1LP, and would suspect that it is at least as good at milling as the small Proxxon. It is also considerably lighter and easier to put away than any capable mill. Axminster do the C0 which weighs 13kg, the C2 weighs 37kg. My Taig weighs about the same as a C0 . It has the side benefit that you also get a lathe!!

I've had a few small mills and used quite a few more. Imo the sieg sx1lp would make most sense for your applications. I would just put up with the weight.

You see the problem with most of the very small machines is the round column. Trust me it soon gets tiresome loosing position when making adjustments.

The Sherline is not a bad second choice, its a nice machine (regretted selling mine) and it could be modified quite easily to better suit your needs. The motor for example would be fairly easy to swap and you could buy a "sensitive drilling attachment" to make drilling easier.

The only other options are an Emco 5 mill or Cowells mill. Unfortunately both of these are quite rare/uncommon so finding one might be a challenge.

I have some friends with small Proxxon MF70 mills and they love them. They are ideal for small modelling work in softer materials. One of them bought a pillar drill within weeks if I recall correctly.

I was looking about that time and it never occurred to be to go so small and light, because I was already focussed on steel and doing relatively-precision engineering, so I knew I had to pay for pounds weight and put up with a permanent installation.

However all I have done in since I got it could have been on on the Proxxon, and most of what I will do could be. It really does come down to what you want to do with it.

@Pete
> Would it be too time consuming to separate into two halves to be put away?
Interesting question.
Maybe one could come up with some kind of quick release bolts??

What about removal of the table - or are we saying that it already weights c 50KG WITHOUT the table, and with the table it's c. 60Kg

@SillOldDuffer

If buying 2 machines, what would you recommend for the high speed small one (if not the Proxxon MF70)?

> ...which suggests trying to combine high-rpm drilling and low-rpm milling in one machine is mechanically tricky.

Wait, exactly why are milling machines LOW rpm?
I thought it was just about getting a good cutting speed. And the outside edge of a drill will have the same cutting speed as the side of a milling blade, no?

> For that reason a specialist high-speed drill for small diameters
> will work well with a dinky motor and modest bearings hopeless for milling.
Yes, the bearings will blow up.

> And the power and bearings of a milling machine don't favour high speed.
Why?
And nowadays you see good quality robust bearings are all over place (e.g. on car wheels)
Surely power should help get up to speed.

@Frances IoM
TBH, this all sounds way beyond me.
What's a "DTI"?

@Peter Cook 6
> As far as I am aware [n?]either the Taig nor the Sherline mills
> have quills for drilling. Both rely on the Z-axis leadscrew for such motion...
I don't really understand.
Does this mean that you need to raise to milling table itself in order to drill?

Re getting a lathe instead, that would mean turning the part in question, yes?
In which case, no most of the time that won't be possible.

@Roger Best
Do you ever cut mild steel? What is the maximum diameter for cutting mild steel?
Some reviews think Proxxon MF70 flexes too much.

e.g. Although I've not watched the whole thing yet, this (Russian?) reviewer Sergey Kutuzov seems to find quite a lot wrong with the build quality...
**LINK**

Are there any alternative SMALL (and therefore high speed [e.g. 10,000+RPM] ) milling machines, that would be alternatives to the Proxxon MF70, but which have better build quality?

I think it's 4 cap head screws, probably take you a minute to unscrew, I'd guess this would split the weight roughly 50/50, the weight of the column, head and motor one half, the base and table the other half.

When I sold my x2, the next size up machine, i picked the whole thing up from the bench and put it in his car without any difficulties, the next size down split in 2 pieces could be lifted on to a shelf easily.

As an experiment I drilled a 3mm hole in a piece of 3mm thick probably mild steel with my MF70. The drill was a new Proxxon shortseries drill from one of their sets. Speed was minimum, 5000rpm, the feed was wind as fast as you can till the motor starts to stall. With more consideration given to the feed it would probably have been better but it worked. Here is a video clip:

**LINK**

Couple of points, Sherline do a sensative drilling attachment specifically aimed at small drills which negates the need for a quill. If they did put a quill on it that would likely take it over your initial weight limit, can't have both.

As I have said before I would rather do without a high top speed that be stuck with a high low speed. Sone odd numbers in that Wiki chart you looked at.

One other thing to think about if you go to separate machines. How are you going to mark out and position all these small holes? Taking your plates with the accurate angled side, do you really want to be marking out 70 odd holes and then picking up the position on the part to drill a small hole. Far easier on the mill to use that to position the first hole and then you have a decent size table to mount jigs etc so all the other holes can be positioned with repeatability.

Always, always listen to JasonB. I can only ever remember totally agreeing with his advice. ie.get a sherline.

However, a real alternative might be a Boley jig borer (a mini BCA). I got one under my desk which I can reasonably easily lift onto the desk when needed. Max through size of an 8mm collet is about 4.5mm so it isn't intended to 'drill' above that but not so bad with a stub drill at 5mm. Pics in my album.

Probably not helpful advice as you won't be able to find one if you 'look' but they do turn up.

And btw I have a Proxxon TBM220 drill which I find quite handy. 4mm is really a limit, if already too much. There is some feeling of quality in Proxxon that seems to make them a bit better to use than I expect.

Edited By jaCK Hobson on 01/04/2021 08:31:00

.

That’s pretty

**LINK** for convenience

https://www.model-engineer.co.uk/albums/member_album.asp?a=55241

MichaelG.

A very useful thing!

Dial Test Indicator, sometimes just Dial Indicator or Clock Gauge. Used for checking that work is parallel to the axis on a milling machine, concentric on a lathe and so on. I have a small lever style gauge on a magnetic base and adjustable stand. I use it all the time.

There is also the plunger style gauge. I have one of those too. I keep intending to arrange clamps to hold it parallel to my lathe axes but never got a round tuit.

The MF70 is not magnetic. I've added a couple of bits of 4mm steel plate between the XY table and base on mine so that the magnetic base has something to stick to. Other folks have made clamps to attach one to the spindle housing.

Hi john,

I'm coming late to this debate, sorry. But I faced this very choice a couple of years ago. I went the Proxxon route and frankly it was a mistake.

I do very light engineering with plenty of brass and aluminium aluminium. The Proxxon looked on paper to be ideal but it lacks guts so is painfully slow to make parts with, and its size restricts it by and large to Proxxon consumables.

I bit the bullet and sold it, moving up to a Sherline. I have to move it out of my way frequently due to space restrictions so a 'liftable' machine was essential. The Sherline is easy to get hold of in the UK although it can sometimes take a week or two to get the parts. Mill Hill supplies of Basildon are the main importer and DPP -an online shipper from California - will list parts for you on eBay. (David, on [email protected] - or just enter Sherline milliing machine on eBay search)

My recommendation - get the DRO (easy after fit) and get a 10mm mill bit holder. You can then buy 10mm shank waldon bits from Arc Euro or ACCU.

Whilst I mostly mill Aly and Brass, I have milled mild steel and its just fine. Online videos show it machining a wide range of materials.

If you want to know more - happy to answer, Or talk to Kevin at Mill hill Supplies 01279 418300.

Regards

Stuart

ps. A high speed mill head is available with the sherline if high RPM is essential. Normally it maxes out a 6000 rpm but with the high speed head, I believe 10,000 is achievable.

Stuart

On machines designed for drilling (most small mills and drills) there are two ways to lower the drill bit towards the work. One is to move the whole head down, the second is usually a rack and pinion or similar arrangement that moves the spindle holding the drill bit relative to the head. This parts that move within the head and allow this is known as the quill. If a machine does mot have a quill, then the only way to drill with it is to move the whole head down to feed the drill into the work.

The Sherline & Taig small mills don't have a quill, and to lower the drill into the work you would need to wind the vertical (Z axis) leadscrew down. Accurate in terms of Z position for milling, but slow and cumbersome for hole drilling. You can use a sensitive drilling attachment, but that limits the size of drill (the Sherline unit has a maximum of 4mm).

Using a lathe with a vertical slide for milling doesn't mean turning the work. You mount the workpiece on a vertical slide fitted to the saddle of the lathe, and put the milling cutter in the lathe chuck (use a collet). So the work stays still and the lathe motor rotates the cutter. It's like a small mill laid on its back. If you search "vertical slide" on Warco's site you will see an example fitted to their version of the small lathe.

Peter is right about how long it can take to lower the drill bit by winding the Z axis and if you are doing repetitive work, you would be surprised how tiring on the arm it can be. You can acquire a stepper motor, indeed you can upgrade to full CNC! But if you're going that far there are probably better alternatives available.

Sherline also make a lathe (I've bought both). The lathe uses the same motor/head combination which by the way, has fully variable electronic speed control up to the standard 6000rpm (10,000 max with optional extras). The lathe can also have a mill column fitted creating a combined mill and lathe unit. I'm not sure how useful this is but it does reduce the combined size and cost.

You can probably tell I'm a Sherline fan but I make small, low volume, non repetitive components for which it is ideally suited. Those on this site who build model railway engines would find it woefully inadequate. Horses for courses.

Stuart

Thank you. But have you tried milling mild steel?

J