Lathes & M/C tools

[sagaguy]

I must admit that there are some peculiar angles there but the second from left could be used for turning & facing.

Can you fit the inserts in any position on the holder or do they fit into a recess.

Ray.

[bertiedog]

The basic rule with inserts is any corner can cut, and the ones overhanging the bar at the front are the cutting point in action. You have facing and cutting left and right, but the two at the right I cannot see the overhang details. They look like fast cutters for roughing bars.

Centre held types like this go into a shaped ledge in one set position.

 

No one job is defined by the point on inserts, if the point suits, then use it for the job. All inserts like this should suit most fine finish work as they have formed rounded tips.

 

With a light lathe take only shallow cuts, only build up as you get more experienced.

 

Stephen.

[bertiedog]

The set is described as side and face left and right, face, and the rough face cut left and right, across the box.

 

Stephen.

[Pugsley]

Thanks Stephen, and Ray. I'll give them a try and report back.

[Ohmisterporter]

A strange thing you may find out about carbide tips is that while they will happily remove plenty of material with a deep cut, just gently winding the tool up to the face of the job can result in "ping" as the cutting edge breaks off. I am writing about deep cuts on bigger lathes of course. For the lathes we are discussing here, smaller cuts are prefered. As you build up experience you will get to know what you and your machine can do together.

 

Geoff.

[alcazar]

I've only ever used one carbide tip tool, bought tyo make a thread. It broke early in the process. Never again, total waste of money.

[flubrush]

A strange thing you may find out about carbide tips is that while they will happily remove plenty of material with a deep cut, just gently winding the tool up to the face of the job can result in "ping" as the cutting edge breaks off. I am writing about deep cuts on bigger lathes of course. For the lathes we are discussing here, smaller cuts are prefered. As you build up experience you will get to know what you and your machine can do together.

 

I would agree with that. I find I have to work carbide insert tools quite hard to get a reasonable performance. If I want to do fine finishing cuts then I use HSS or carbon steel tools - especially on non-ferrous materials.

 

Jim.

[bertiedog]

With modern insert tips, it is more to do with chip-breaking with the insert tooling, on a CNC machine centre it is vital to ensure no continuous swarth is made, it would foul the machine badly. The modern machines need swarth size that can be flushed away with coolant reliably. Most inserts have a chip breaker top, a groove which curves the swarth and breaks it up.

 

There are zero top rake types with no groove as well, often used for rougher cuts.

 

Any HSS tool will take a better finish than a carbide, but cannot retain it for long. A carbon tool with hardening can take a finish and last well, but with strictly no overheating when cutting.

 

Most carbide is quite brittle, and chips itself if in any way the cut is intermittent, such as squares in four jaws, or eccentric stock. The first rough could be best done with HSS, and then switch, although one type of material is best with carbide and that is cast iron, which can be very hard at the surface.

 

Do not throw away the carbide tips when chipped and worn, they can be easily re-sharpened on the small diamond steel disks in a mini drill like a Dremel.

 

It is worth removing the tips on new tools cleaning the seat, check there is no burrs on the seat or around the screw and firmly fit and tighten. Never trap dirt under the tip, it can cause a shatter.

 

There are several grades of carbide including diamond, and nitride types, but for most amateur home use it's best to stick to the normal common types. Many of the specialist types HAVE to operate with continuous copious lubricant at all times, as they are designed to work at higher speeds and feeds than any home workshop.

 

Stephen.

[ozzyo]

Yes, it's one way, but normally division heads, or rotary tables, are used for more than 4 faces and odd numbers, not a square, which would be milled in a vice, the bar held vertically, and automatically give the two axis for four accurate faces without any division being required.

 

When new to milling it always pays to take the simplest way any way, and few here are going to have a rotary table or centres, let alone collets capable of taking a axle box blank, but they should have a decent machine vice, a basic for all mills.

 

 

Hello Stephen,

 

thanks for the reply. Now to business.

 

Using a D/H 3 index's. 1 using a 8mm cutter set on the center of the horne slot, 2 the index for the 6mm square, the index for 4mm base of the horne slot.

 

Using a vice 8 index's, 1 the height of the horne block, 2 the first face at 7mm, 3 the second face at 7mm, 4 the first face at 6mm, 5 the second face at 6mm, 6 the height of the side and face cutter for the horne slot, 7 the depth of the first horne slot at 5mm, 8 the second horne slot to 4mm.

 

Or if you part it off before the horne slots, 1 depth of the horn slot to 5mm, 2 the center of the horne slot.

 

So the best you could manage would be 8 index's, doing it in a vice.

 

Doing it in a D/H 3 index's.

 

For M/Cing up to about 24 flats using a D/H on some models you dont even use the dividing handle (drop it out of gear), just use the direct indexing plate at the head stock end.

 

I have noticed that you have not replyed to my other two points, M/Cing the horne blocks between centers and the M/Cing of the small hex headed bolt.

 

OzzyO.

[bertiedog]

I did cover the other points, at no point have I ever mounted hornblocks between centres, there's no need, the accuracy is up to the milling operator.

 

Whilst the faces may be accurately set by setting on centres, and rotating for the opposite face, the average home mechanic has not got the gear to do it. If a hornblock ends up with the axle out of line it is simply bad practice in milling. For 3 ¹/₂ and 5 inch gauge the block is fully finished before coordinate drilling the axle holes in the mill and then boring in situ in the mill. Each horn lock is dropped into the jigged vice and gets the same setting applied.

Everybody has a milling vice with the milling machine, but few have rotary tables or division chucks to hand.

 

Very few models are going to need hex heads milled, even in live steam models, I do use rotary tables to make Bugatti Bolts, with integral washer heads, in 10/12/14 BA for miniature steam engines, these are made entirely by milling the head, no lathe work. In many years in model engineering the people who make hex bolts could be counted as .......very near zero!!

 

The bolts are made mounted in a collet, with the rotary table underneath to provide the hex division via a direct hex plate to save using the handle, which is de-clutched. Two stops on the bed are set to allow the cut for the bolt faces and the washer edge is a continuous rotation with the handle engaged on the second stop. The bolt top is done freehand with the top tip.

 

Stephen.

[bertiedog]

A lathe tool holder to make at home, takes 1/8 carbide drill shanks, you can buy broken drills as shows or gather your own, make in steel, with the screw bearing on a brass disk to soften the grip so the carbide does not shatter.

 

The tip shape is ground on a diamond disk, or green grit wheel, to whatever shape you want, and the finish is as good as the grinding standard. Very good for fine light work.

 

The body size is simply made to suit the lathe tool holder from 6mm upwards. The retaining bolt I use is 2BA or 5mm metric.

 

 

Stephen.

[ozzyo]

I did cover the other points, at no point have I ever mounted hornblocks between centres, there's no need, the accuracy is up to the milling operator.

 

Whilst the faces may be accurately set by setting on centres, and rotating for the opposite face, the average home mechanic has not got the gear to do it. If a hornblock ends up with the axle out of line it is simply bad practice in milling. For 3 ¹/₂ and 5 inch gauge the block is fully finished before coordinate drilling the axle holes in the mill and then boring in situ in the mill. Each horn lock is dropped into the jigged vice and gets the same setting applied.

Everybody has a milling vice with the milling machine, but few have rotary tables or division chucks to hand.

 

Very few models are going to need hex heads milled, even in live steam models, I do use rotary tables to make Bugatti Bolts, with integral washer heads, in 10/12/14 BA for miniature steam engines, these are made entirely by milling the head, no lathe work. In many years in model engineering the people who make hex bolts could be counted as .......very near zero!!

 

The bolts are made mounted in a collet, with the rotary table underneath to provide the hex division via a direct hex plate to save using the handle, which is de-clutched. Two stops on the bed are set to allow the cut for the bolt faces and the washer edge is a continuous rotation with the handle engaged on the second stop. The bolt top is done freehand with the top tip.

 

Stephen.

 

 

 

 

Stephen,

 

I have one or two rough quoits from you, #157, as it is used mainly for between center work ( the dividing head), #163 when most work on a dividing head is held between centers, #164 the work is held on the two centers (or some thing similar).

 

Yes I would M/C 3 1/2" or 5" axle boxes that way. but my example was for some thing 6mm square.

 

I have not seen a reply to M/Cing a 0.5mm bolt with a 1mm head and how you would do it.

 

All M/C accuracy is always up to the operator.

 

If you do want some small BA bolts with hex heads try Items Mail Order.

 

 

OzzyO.

 

PS. if we had a lot of hex heads to mill we would some times set up a pair of side and face cutters to do the top and bottom faces in one cut. This only took three cuts rather then six, but it all depended on how many we had to do. We were not on piece work at the time.

[bertiedog]

We do seem to be at odds un-needed, everybody has ways of machining parts, all I am suggesting is keeping it within the limits of a home machinist, without a rotary table, CNC or even a mill if they are working with the mill as a lathe.

 

Small headed BA bolts are indeed made, but I was not describing that, but the making of Bugatti Type bolts use by Bugatti on cars, Aero engines and Italian engineering that Bugatti was involved in.

 

Two types were made, on for the cars with a constant sized head, despite different bolt sizes. The other type was related to the bolts size, but with a smaller hex than the diameter of the thread.

 

They all have a washer shaped head to spread the load, and work better than ordinary bolts, especially for appearance, fit of a socket, and the need in the case of the Bugatti cars , the need for only one spanner and socket size for all the main bolts.

Such miniature Bugatti bolts have never been made commercially, anywhere.

[bertiedog]

This the Bugatti bolt, and matching nuts, as it has been queried by another member, a bolt with a flange instead of the head bearing on the load surface, they are far more sophisticated than plain bolts, the picture is a car set with two sizes of head plus hand tightening butterfly types for covers in a 1920's engine. Most cars have hex heads, some with square heads.

Although famous for his cars, Bugatti was a brilliant engineer, designing engines for aircraft and high speed steam engines of advanced design.

 

Stephen.

[ozzyo]

Professional advise request chaps!

 

I'm considering buying a small/mini lathe, but never worked with it... I found http://www.micromark.com (US based) and they happen to have 2 mini lathes. Search for the items 82710 (7"x14", USD 590) and 84631 (7"x16", USD 690). Problem is, being US based, the power supply: 110 VAC... Oh, and the USD 500 for getting the stuff here in Europe, not including Customs duties... So, should I buy one of these or select a European supplier (if so, which one?)

 

 

 

You could have a look at Axminster tools on the web, do some lathes about the same size, will be a bit less in the P&P department.

 

OzzyO.

[bertiedog]

The UK suppliers, Clarke, Axminster, Warco, Chester tools, Arc Euro, all supply versions of the basic Chinese Sieg Models, 7x10, 7x12, 7x14, in various small details they differ, for instance Warco have the latest tailstock design, and some suppliers offer the very latest coreless DC motor on the top model.

 

All would be 240VAC supply for the UK (approved), and all have the US made speed Boards or up-rated types.

The exact spec' does vary, so contact the suppliers, and ensure the tailstock is the new lever lock in the deal....or make an offer for "the older models" the lever can be added later!!!!

 

I have personally set up Chester, Clarke and Warco versions, no problems at all, just an inspection, clean, and go! Warco will pre-inspect anyway.

 

Stephen.

[Baby Deltic]

Thanks! Any suggestions on which machine (brand, type, etc).

 

Colchester Mascot 1600.

 

Just kidding. The Colchester Triumph 2000 and Mascot 1600 were always my favourite lathes, with plenty of grunt for roughing out. Too big for domestic work. The Axemister and Seig do look good.

 

With lathes, its 'horses for courses'. It depends on the size of the work you are going to want to do on the lathe. Obviously the distance between centres, the swing and the spindle bore/chuck size have to be big enough. If you only want to trim the pinpoints on OO scale axles and skim wheelsets, a Unimat style lathe would probably suffice. If you want to turn flywheels and drive shafts, and profile steam loco wheels, maybe a seig or Axeminster. For larger 'garage' lathes, you could look on Ebay, but buyer beware.

There are often Myford Super Sevens, Colchester Chipmaster's and Colchester Students being flogged online. I say buyer beware, because some of these lathes are quite old, and may have worn slides and spindle bearings, and backlash in the dials. I've worked on a few old lathes in my time, and its annoying when you start taper turning because the slides are worn.

[bertiedog]

http://www.warco.co....D4121A9297.aspx

This is the Warco, with extras, check for price with vat and delivery, they may have deal.

It has the new tailstock with cam lock.

 

Also they offer a certificate of accuracy......

[halfwit]

Colchester Mascot 1600.

 

Just kidding. The Colchester Triumph 2000 and Mascot 1600 were always my favourite lathes, with plenty of grunt for roughing out. Too big for domestic work. The Axemister and Seig do look good.

 

With lathes, its 'horses for courses'. It depends on the size of the work you are going to want to do on the lathe. Obviously the distance between centres, the swing and the spindle bore/chuck size have to be big enough. If you only want to trim the pinpoints on OO scale axles and skim wheelsets, a Unimat style lathe would probably suffice. If you want to turn flywheels and drive shafts, and profile steam loco wheels, maybe a seig or Axeminster. For larger 'garage' lathes, you could look on Ebay, but buyer beware.

There are often Myford Super Sevens, Colchester Chipmaster's and Colchester Students being flogged online. I say buyer beware, because some of these lathes are quite old, and may have worn slides and spindle bearings, and backlash in the dials. I've worked on a few old lathes in my time, and its annoying when you start taper turning because the slides are worn.

 

I worked on a few Mascots, usually 2000's, and Triumphs back in my machine shop days. I think of them as the Ford Cortina of the lathe world. The ones I used always leaked oil from the saddle. I much prefered Harrisons, I used a M500 for a few years. Not as heavily built as a Mascot but a lot nicer to use.

[bertiedog]

http://www.machinemart.co.uk/shop/product/details/cl300m-metal-lathe/path/metal-lathes-milldrills

 

This is the Machine Mart Clarke, older tailstock, ( but you can change, modify or home build the cam lock), and the older motor, which is perfectly good, Warco claim more for their motor version, but you pay more.

[bertiedog]

http://www.axminster.co.uk/axminster-sieg-sc2-mini-lathe-prod809904/

 

The Axminster up rated version with the 500 watt coreless motor, it appears to still have the nut lock tailstock, but this can be changed very easily on all Sieg lathes.

 

Cam lock kits are made, or you can use a dedicated spanner, or make a lock yourself in an afternoon.

[ozzyo]

Professional advise request chaps!

 

I'm considering buying a small/mini lathe, but never worked with it... I found http://www.micromark.com (US based) and they happen to have 2 mini lathes. Search for the items 82710 (7"x14", USD 590) and 84631 (7"x16", USD 690). Problem is, being US based, the power supply: 110 VAC... Oh, and the USD 500 for getting the stuff here in Europe, not including Customs duties... So, should I buy one of these or select a European supplier (if so, which one?)

 

 

 

Hello Dutch Master,

 

just had a look in my Axminster cat. two lathes that my do for you are the SIEG 2 series details as follows,

center height 90mm, between centers 300mm, cross slide travel 65mm, headstock taper 3MT, tailstock taper 3MT.

 

SIEG C2A £436.50 (fitted with digital read out on the carriage X & Y travel),

 

SIEG SC2 £499.50 (no digital read out but can be bought £86.95)

 

Bits that I would add are as follows,

 

digital read out £86 .95,

quick change tool post £43.50,

4 jaw chuck £72.00,

collet holder (chuck) £63.96,

set of ER32 collets £117.50.

 

I think that I would go for the SIEG SC2 with the spindle speed read out (£69.50) and all the above fittings so all up £952.91.

 

You dont need the collets and collet holder so you could save £181.46 bring the price down to £771.45, which will bring it to something like the Micro Mark price.

 

OzzyO.

 

PS. dont forget the tools a set of 5 for £11.86 or a set of 11 for £25.99.

[Pugsley]

Thanks for the answers to my previous numpty question - I've got those set up nicely now after the clarification about what should be used for what task.

 

My next numpty question relates to this:

 

How do I set this form tool up and mount it in the lathe? I'm a bit confused as it doesn't look like I was expecting it to. All help much appreciated.

[bertiedog]

It appears to be a round form tool for wheels, a segment type, and requires a holder, a bolt through the middle to attach the form tool to a tool holder to suit the lathe.

 

The tool bar should be the normal tool size, with a hole drilled through the side and a nut and bolt to attach the form tool to it. For small lathes the bar may have a larger head that sticks out beyond the reach of the tool bar.

 

• The hole could be tapped to take just a bolt as well, both ways are valid. The tool bar should be mild steel, it does not have to be tool steel.

• The form tool is set to exact centre height for the lathe, checked against a tail stock centre for instance, and the form bolted up very firmly.

• The lathe is set to a slow speed,(100+), and the form is plunge cut slowly and steadily into the bar of material to the required depth, measured and checked, and then repeated by the dials or stops for the next wheel.

• The saddle should be locked firmly, and the work advanced by loosening the chuck after parting off each wheel, with a rear parting tool, or for a batch, could be parted off after, say, six tyres are formed.

There are several caveats to form tools, they should be used at relatively low speeds, with a cutting lubricant with steel, or dry with brass. Nickel tyres usually cut dry, but can use cutting oil if the nickel is tough.

When steel is used , then make sure it is a leaded free cutting type, not common mild steel.

 

• The reason the form is used like this is the form is re-sharpenable by just grind the face lightly and honing with a polished drill blank to de-burr. Never touch the outer form edge, only the segment form.

Should the form tool edge reproduce scratches on the work, it should be re-ground again, till the marks are gone. The form tool will last ages, with dozens of re-sharpenings possible.

Picture should show the form edge level, not raised, the bolt must be a good fit to the hole in the form tool, might need a sleeve turned to make it snug fit. ALSO washers should be used to spread the pressure.

Stephen

[Pugsley]

Thanks Stephen.