Sieg SX2 or SX2.7

[Nikhil Bhale]

I know this is an old topic discussed in hundreds of forums but I am posting it anyways.
I just got myself unmachined kits from PM research for #1 and #5 steam engines. I have a Sieg C4 lathe but I may need a mill to complete these engines.
So the question is which one is preferable Sieg SX2 or SX2.7 ?
SX2 is selling for about USD 1000 and SX2.7 for USD 2000 here in India. I need a machine that will work out of the box and not need any mods.
I also considered some Indian mills and now it has become truly confusing.
https://ravimachines.com/product/drilling-cum-milling-machine-19mm/ about USD 650 or
https://ravimachines.com/product/drilling-cum-milling-machine-25mm/ about USD 800 or
https://ravimachines.com/product/zay7020g-column-type-geared-drive-fine-feed/ about USD 1900

Any advise or opinion appreciated.
P.S. I have to move the machine to my spare room on first floor so weight of machine is definetly an issue.

Thanks
Regards
Nikhil

 

[bazmak]

I have the sx2 long table and it does everything i have ever wanted.It will work out of the box but i have done mods.Gas strut etc
I bought the fixed column the swivel coumn is a nightmare to tram i understand.I got r8 spindle.The sieg 2.7 is a bigger beast
so in your situation is far too heavy

 

[awake]

Nikhil, the trade-off is going to be capacity vs. weight vs. cost. With mills, the capacity is not just the size and motion of the table, but also the maximum distance between the table and the spindle - you can eat up that space very quickly with a drill chuck, drill, vise, and part. That may mean, with a smaller machine, creative ways of holding the drill bits and/ or parts!

The good news on all of these Sieg type machines is the dovetail column, allowing you to move the head up and down without losing position on the X and Y - something you almost always have to do when moving between endmills and drill bits. I have an ancient mill-drill with a round column (not the typical Rong-Fu style - even more primitive than that!), and it requires a lot of extra effort to manage.

I wasn't able to access the links you had to the Indian machines, but would be curious to see what is available.

Where in India are you? I've only been to India once, down in the South (Kerala) for a couple of weeks - I thoroughly enjoyed it. Since most of my childhood was in Southeast Asia, it felt very much like home to me! But I would love to visit more of the country ... maybe someday ...

 

[blanik]

I have had a Sieg SX2.7 for about three years now. Out of the box, it needed a good cleaning to get the sticky anti-rust grease cleaned off, and then a thorough lubrication of all of the sliding surfaces and the lead screws.. Also, all of the gibs needed to be adjusted, as the gibs were all loose for shipment. The gibs are all of the tapered gib design, so adjustment is quick and easy - just one slot headed screw at each end of each gib. The lead screw nuts all have anti-backlash adjustments, but none needed adjusting on delivery.

The Column Base and the Head are not adjustable (easily) - the machine is trammed at the factory and then locking pins are installed to ensure the machine can be reassembled back into a trammed state if you ever have to completely disassemble it. So, in simple terms, the SX-2.7 is trammed at the factory and is not designed to be tram adjusted in use. I check the tram state of my mill every few months, and the mill has shown no sign of going out of tram so far. Should the base of the column ever need to be adjusted to correct a tram error, you would need to shim the column base.

I have made two modifications to my SX-2.7. Mod 1 was to install an X Axis Power Feed (https://www.ausee.com.au/shop/item.aspx?itemid=3884). Sieg's power feed is OK. It certainly beats hand cranking the X Axis for long periods. The use of the Power Feed also greatly improves the surface finish. My only issue with Sieg's power feed is that at it's slowest feed rate, it is still too fast for use with a 100mm Fly Cutter.

The Second modification I made to the SX-2.7 was to install a Two Axis DRO. A very useful addition to the mill.

I have a third mod which is currently a work-in-progress. That is the addition of a second "High Speed" spindle. The spindle is a 2000 rpm to 25,000 rpm unit (a 3 phase motor driven by a single phase to three phase variable speed controller) that I intend to use with small (typically under 2mm diameter) end mills, for milling of mainly brass components of clocks and other small items.

Once you've unpacked the mill, it weighs 101 Kg fully assembled. Two people can manage to lift the mill OK. But DO NOT let anyone lift the mill by lifting on the mill's table. You could remove the mill table and the mechanism beneath the table to reduce the weight of the mill so you can carry it up the stairs more easily, but by doing that you'll only reduce the weight by maybe 20 kg. I don't recommend removing the mill head to reduce the weight, as reinstalling and tramming the head is not a trivial task.

I hope that information has been useful.

Regards,

RoyG

 

[Nikhil Bhale]

Thank you all for your suggestions.
@awake I live in central part India. Its mostly hot and dry, not much tourists, though we have some tiger reserves here.
@blanik I was thinking the same thing. Remove the column and then it will be easier to get it to my room. But I will have to rethink it.
@bazmak SX2 i am offered is the basic version.

 

[Nikhil Bhale]

Hi
Finally I was able to get home from work after 7 months.
And first thing I did was order a Sieg X2.7 mill.
Now I want to get some tooling for it.
I already got a ER 25 collet set, some carbide end mill (3, 6, 8,10 and 12mm) a 100mm milling vice and a clamping kit.
What else do I need immediately?
I plan to work on PM research mill engine or coke bottle engine. (I have castings for both).
I know all the tools are Indian and there was a recent tread about India tools.

Any suggestions would be helpful.

Regards
Nikhil

 

[awake]

Nikhil,

My experience is that once you have some basic cutting tools, you have to jump in and start machining in order to figure out what you need next. That said, I do have a few suggestions to offer:

First: The one thing that I think you MUST have before you go any further is an edge finder. I use a simple, inexpensive spring-loaded model that has lasted me for years and years. Absolutely essential for accurate positioning. Even better with a DRO, but I have done a LOT of milling with just the edge finder and the dials, long before I got a DRO.

Second: Get some good-quality high-speed steel end mills. Carbide is great for high-speed removal of material and for milling hard metal ... but it is also much, much easier to break. It is not as forgiving of interrupted cuts, and needs a rigid setup ... and it is a lot more expensive. You may eventually decide to run with all carbide, but I would suggest starting out with HSS as you are learning the capabilities and quirks of your machine. You may find that HSS takes care of 95% of your machining needs - that is my experience. The only carbide I run is a 2" face mill with carbide inserts, good for facing off large swathes of material and for getting under a hard layer of mill scale.

Third: As you move further along, you may find that you need a boring head ... a rotary table ... a dividing head (which might be the rotary table with accessories, e.g., for cutting gears) ... one or more fly cutters ... v-blocks ... and the list goes on. You will likely need some milling cutters beyond just straight end mills - t-slot or woodruff cutters, dovetail cutters; gear cutters if you want to cut gears; and so on. Some of the items in this list I have made rather than bought - fly cutters are particularly easy to make with basic lathe and mill tooling, but I've also made a good many specialty cutters (t-slot, dovetail, v-groove), and I made my own boring head. It turns out that I am one of those people who like making tooling as much as I like using the tools to make other projects! And indeed, with the right stock and equipment, one could in theory make any tool one wants ... but be warned that making it yourself does not always save money, and never saves time. When the budget permits and the time or interest does not, I will buy tools as the need emerges.

Fourth: Some things are not absolutely essential, but nice conveniences to have. A DRO would probably be at the top of that list for me. Another would be a coaxial indicator for finding the center of round features. You can do this also with a much less expensive dial indicator and a way to hold it in or onto the spindle. You can even do this - with care and experience - using the edge finder, but depending on the size of the feature, that can be much harder and less reliable. Power feeds are on this list as well.

I am sure that each of us will have a somewhat different list, with different priorities on what should be first, and hopefully others will share their lists to give you a broader selection of perspectives. Meanwhile, I hope this gives you at least some ideas to work on ...

 

[Nikhil Bhale]

Thanks Awake
That is a comprehensive solution you have provided.
I will get additional tooling as and when required.
As for edge finder I have ordered it now.
For end mills I was initially going to get HSS cobalt end mills.
But when I visited a shop in Mumbai, HSS and carbide were same price. So I purchased carbide thinking they will last longer.
In India tools are cheap. Don't know about quality as I have hardly used milling machine before.

First thing when the machine is delivered is to clean it and make some chips.
I will have to practice before I try milling the castings.

 

[awake]

Ah, it will be interesting to see what your results are with the carbide tooling. Normally carbide is at least twice as expensive as HSS, sometimes even more - at least that is the case for the tooling we can buy here in the US (even when it is import tooling from China).

Let us know how it goes!

 

[kwoodhands]

Thanks Awake
That is a comprehensive solution you have provided.
I will get additional tooling as and when required.
As for edge finder I have ordered it now.
For end mills I was initially going to get HSS cobalt end mills.
But when I visited a shop in Mumbai, HSS and carbide were same price. So I purchased carbide thinking they will last longer.
In India tools are cheap. Don't know about quality as I have hardly used milling machine before.

First thing when the machine is delivered is to clean it and make some chips.
I will have to practice before I try milling the castings.

I would add to the list a clamping set. The T-slots on mills may be different widths. My mill has 5/8" wide slots, some mills have 9/16" slots. Your tools may be metric so the dimensions I used are arbitrary.
You will need a milling vice. Kurt vices are known as high quality but they cost a lot. An Indian made quality vice is probably a good bet. I have a 6" rotary table from India that I am very satisfied with.
I use R-8 holders instead of collets for end mills.
A small vacuum cleaner to gather chips is handy.
Andy mentioner DRO's. I use digital scales that are quite accurate for home shop use. I have a 36" digital scale on the X axis ( long way ) and a 6" scale on the Z axis ( vertically for the spindle height).
These cost much less than true DRO's but work well for me.
Make sure any mill you but has a power feed for the X axis.
A hint to install a vice parallel with the table slots, get a piece of steel, aluminum etc that is 4 or 5" wide, 3/16/1/4" thick and about 16" long. The piece gets a cut out 5" or so wider than the vice and deep enough so when the cut out piece sits centered in the vice ,the "legs" will go down into the slots.
This piece will resemble the letter C when rotated 90°. The C goes in the vice with the legs down and the legs pushed forward towards the moving jaw. I have a 3" deep vice, I pack the C with a 1-2-3 block with the 1" thickness against the C and several parallels behind the block. Then I snug up the moving jaw. I loosen the nuts that hold the vice, pull the vice towards me until the legs of the C hit tightly on both sides of the vice. Then snug and then tighten the nuts.
I had to lap the C initially after cutting out the middle. You may have to do the same, one side only is fine. Just the side that hits the slot.
I checked the vice tram with a dial test indicator several times. The needle moved less than .001
my indicator only goes to 3 places.
This method was shown to me by another Home shop machinist.
mike

 

[John Antliff]

I would suggest that you install a key in the base of the vise - this is achieved by machining up a length of mild steel to the width of the table slot that will normally be under the centre of the vice i.e.the bolt down flanges. Note - on my machine the centre slot is a different width to the others not by much but significantly smaller. I think the manufacturer only cut this one slot precisely, the others were ripped out. Having got your piece of metal as a key to fit the slot, mount it in the vice jaws so that half of it is proud and then turn the vice upside down such that the proud part fits into the selected table slot. Fix the vice down firmly with straps and cut a slot across the base of the vice i.e. parallel to X axis, to the same width and half the depth of the key metal. No you have a slot in the bottom of the vice that echoes the alignment of the table slot. Cut the metal key to length, insert into the slot in the vice and drill and tap 2 suitable holes, fix the key using cap screws.
If you do this accurately then the vice will always sit in the slot parallel to the table ways. Check periodically using a dial indicator on the fixed jaw inner face that the vice is parallel or pretty close to it. Necessity demands that the key fits the table slot without shake and as such, alignment is affected by how close this fit is but for normal jobs it will be close enough. A tight fit is desirable as over time it will get looser due to wear. I have done this to all of my tools that are mounted on the table like the rotary table, dividing head, spin indexer and tail stock, 2nd vice etc. to make switching devices quick and easy.
Hope this helps.

 

[ShopShoe]

Something I don't see mentioned is that you need some precision ways to measure and set up, if you don't have them. I would suggest you need a Dial Test Indicator to set up your vise parallel and perpendicular to the table travels and to set up anything else you clamp directly to the table.

Don't confuse the Dial Test Indicator with a Dial Indicator, they are different things, and you probably will need both as things progress. Cheap is OK to start, but precison is better and more expensive.

I would suggest you need machinist squares of multiple sizes, a digital or dial caliper, and a micrometer. The caliper is OK to start. You will need something to act as a flat surface for measurement and laying out parts, and for lapping parts smooth and flat: The Surface Plate is traditionally made of granite or metal, but you can get by with a piece of plate glass.

There's more, but as was said above, you need to start machining to figure out what you need.

Feel free to ask us more,

--ShopShoe

 

[Nikhil Bhale]

Hi
I finally got the mill home. A Sieg X2.7 mill.
I got some carbide end mills, a 100 mm milling vice, ER 32 collet holder and collects, clamping kit all Indian made.
And I started practicing milling.
This is my first mill and I was really surprised to see all the swarf it makes.
On my lathe most of the cutting ends up in the pan below but milling machine throws it all across the room.
I may need to invest it a good shop vac.
I also chipped my 12mm end mill. It fell down when I was trying to loosen the collet nut.
Some 2 flute end mills, angle plate, dial test indicator, steel parallel are on order and on the way.
I have castings kit for PM research #1 and #5 engines.
But i won't touch them till I am somewhat confident about my milling skills.

Regards
Nikhil

 

[awake]

You're off to a good start - making swarf! Listen to the machine as you try different depths of cut, cutter rpm, feed - let the machine tell you when it wants more, or less, or is in the sweet spot.

Be warned that chips coming off can be hot, and as you say, they go everywhere!

 

[JohnBDownunder]

Hi Nikhil, Well you are certainly not the first, nor will you be that last to chip an end mill loosening the collet nut.
I finally got into the habit of putting a piece of old fabric material on the table or vise before loosening the collet nut. If the bit falls it hopefully lands on the material. Not the hard edge so no chipping.

I agree with Andy about learning to listen to your machine. Yes there are speeds and feeds you can use but mostly they are for production machines. Our small hobby mills and lathes soon let us know and much to my brother's horror (A machinist and teacher by trade) I subscribe to the T.S.A.R. system, (That Sounds About Right). You do get to know your machine noises after a while.

Enjoy the hobby, make swarf and learn stuff by doing.
John B