Basic lathe tools to get started

[precisionworks]

I'm not sure WHY he's doing it this way,

Because nothing has to be moved :nana:

The compound is always set at 29° more or less. Cutting that angle with a boring bar requires running the spindle in reverse & feeding on the far side of the part. Habit I guess. Fast too.

 

[darkzero]

I'm not sure WHY he's doing it this way

I also chamfer this way 90% of the time. It's much more convienent this way & I just use that method naturally. Sometimes I even machine tapers this way too. Don't remember why or when I started doing it this way but I probably learned it from Barry if he mentioned the method in the past.

 

[las3r]

Does anyone no any good sales going on right now for any good lathe bits ?

Mostly for cutting grooves and cutting mags

 

[wquiles]

Does anyone no any good sales going on right now for any good lathe bits ?

Mostly for cutting grooves and cutting mags

The grooving tool to get (in my humble opinion) is the Top Notch system from Kennametal. TONS of cheap inserts on Ebay, specially the size #3. The same tool holder can use different inserts to do various styles of grooving (including threading), as seen here in this post:
http://www.candlepowerforums.com/vb/showthread.php?333154-best-grooving-tool&highlight=Top+Notch

Here is one on Ebay (for external threading/grooving):
http://www.ebay.com/itm/new-kenname...950?pt=LH_DefaultDomain_0&hash=item4cff7715d6


This top notch tool is what I use for grooving bodies/heads on my custom 1xD's.


Now you also say on sale "now". Just set up a search on Ebay and get notified daily. Eventually you will find a good one

Will

 

[precisionworks]

Does anyone no any good sales going on right now for any good lathe bits ?

Mostly for cutting grooves and cutting mags

The term "lathe bits" has many interpretations. One is a square bar of HSS with a ground edge. Another is a square bar of steel with a brazed on carbide tip. Probably what you want is a tool holder that uses carbide inserts (like those that Will referenced).

This one has a 3/4" shank & is too large for your tool blocks but it's the type to look for: Kenna Top Notch

 

[BVH]

While not for my lathe, do the quick change R-8 collet systems for mills provide decent accuracy - accuracy equal to individual draw bar type R-8 collets? There's one on Ebay for $350. ERF-38740-D - ER-40. Can't see a brand unless ERF is a brand. I forget what the ER40 and lower numbers mean? I would be using them on a small, not a mini, mill drill like the grizzly 0704.

 

[darkzero]

While not for my lathe, do the quick change R-8 collet systems for mills provide decent accuracy - accuracy equal to individual draw bar type R-8 collets? There's one on Ebay for $350. ERF-38740-D - ER-40. Can't see a brand unless ERF is a brand. I forget what the ER40 and lower numbers mean? I would be using them on a small, not a mini, mill drill like the grizzly 0704.

You should be fine using R8 collets. The ER number is the size of the collets with ER 8 being the smallest & ER 40 being the largest. It's not exact but a ER 40 collet is close to 40mm in dia, ER 32, close to 32mm, etc. So each ER collet family will have a max size (shank), ie. 1"(?) for ER 40, 3/4" for ER 32, 3/16" for ER 8. ER collets also have a wider clamping range for each individual size collet compared to R8. I believe ER collets also have better clamping area compared to R8.

Using a collet chuck can make collet changes quicker & easier especially with larger full size knee mills like a BP where you would have to reach way up on top to loosen the drawbar, break the R8 collet loose, then proceed to unscrew the remaining of the drawbar to take the R8 collet out. But in theory with a collet chuck you would loose ridgity as a R8 collet, you're tool would be as close to/inside the spindle as you can get. But I don't know, I've never used a collet chuck in a vertical mill, only R8.

What's important is you have to think about the size of the collet type. An ER 40 might be too big for a smaller size mill. A collet chuck will also eat up valuable Z axis capacity on a smaller mill. The ER 40 might sound better cause you can go up to 1" but you also have to think about whether a small mill will benefit using a 1" tool or even run one at all depending on what it is. They make smaller sizes for a reason. I think ER 40 might be too large for a Grizzly 0704. You might be better off just using R8.

 

[tino_ale]

Hey guys,

As I am ordering a PM1236 so I need to build a shop list. I'm starting from scratch in the lathe business so I'm focussing on the must-have first.

Setting up, cleaning, break-in, lubes... :
- honda spray cleaner and polish or WD40 for cleaning
got it
- precision bubble level
- headstock oil to replace original oil after beak-in
- hard drive or strong magnet
got it
- mason feet or equivalent
- way oil
- ball "nipple" grease gun

Minimum cutting tooling :
- QCTP PM "kit" =RH and LH cutting tool + straight cutting tool + boring bar+ DCMT/DCGT Inserts or CCGT/CCMT
got it but don't know which inserts I should request
- another small boring bar for small ID boring
- parting tool
- threading tool for OD threading
- threading tool for ID threading
- center drill
- drill bits set
- steady rest, follow rest, drill chuck, 3-jaws and 4 jaws chucks, spindle plate, dead and live center,
got it : all included in PM preferred package

Other tooling :
- magnetic base + dial indicator
got it
- 6" caliper and 0-1" micrometer
got it

Before I start asking questions on each piece I need to source, do you guys think this list is reasonably complete ?
Any help much appreciated

 

[gadget_lover]

In addition to the above...

A dial test indicator (DTI) in .0005 or better for precision measurements of concentricity. The dial indicator usually has long travel of an inch or more. The DTI is frequently .100 inch movement.

The inserts have to match your tools. Matt should be able to tell you what sizes and shapes you need for the tools that you got. It is likely that there is a number like CCMT 32.50 somewhere in the packing. CCMT is the shape and 32.50 is the size. There are different grades of carbide, some of which are hard and sharp (but brittle) and others that are less fragile that can handle interrupted cuts. You'll have to figure out what you need to match the work you will be doing.

You'll also need cutting oil and tapping fluid.

Dan

 

[tino_ale]

What I have is a DTI, what I don't is a dial indicator (my bad). I don't feet I'll need a DI immediately, in fact, I'm not sure I'll need it at all.

Thanks for the other info.:thumbsup:

 

[gadget_lover]

What I have is a DTI, what I don't is a dial indicator (my bad). I don't feet I'll need a DI immediately, in fact, I'm not sure I'll need it at all.

Thanks for the other info.:thumbsup:

You will want a dial indicator (with various tips) for centering parts in a 4-jaw. It also works better on rough pieces or pieces with slots that will snag the DTI's probe.

A depth gage is also nice for checking how deep you've cut a pocket.

A large part of machining is a matter of measuring parts and marking parts. For instance if you want to duplicate a flashlight you will need to measure lengths, depths, angles, threads, bores and diameters. If you are making a flashlight from plans you will need to measure the same things to ensure that your parts agree with the plans.

Dan

 

[tino_ale]

Can you recommend a lathe operation handbook ?

 

[gadget_lover]

Can you recommend a lathe operation handbook ?

Many recommend the southbend "how to run a lathe" which is available online via PDF. I searched google and found this: http://vintagemachinery.org/pubs/1617/3789.pdf . The book is 100 years old (copyright 1914 ) but the same basic processes still work.

I learned a lot about working a lathe by reading the US Army's online training manual. The section on lathes is fairly up to date. At one time the manual was publicly available directly from the Army web site. Security concerns shut that down but copies are available from other sources. A copy is available at http://metalwebnews.com/machine-tools/fmt.html .

It's a lot of reading. After all that reading I looked long and hard for videos. There were not too many available 10 years ago. The MIT metal working series had some of the best videos. Start at http://techtv.mit.edu/videos/142-machine-shop-1.

The way I look at learning is that first you need to see what's going on without understanding it. That gives you a point of reference to attach to the knowledge. Then you need to read about it and learn the "what" and "why". Videos can help there. Then you test the knowledge by attempting the skills, studying any aspect that did not go exactly as you expected. The objective is to be able to confidently approach a task with an expectation that there will be no surprises.

Daniel

 

[tino_ale]

Excellent ! That should be enough to keep me busy for years

 

[gadget_lover]

It's really much less complex than it seems. You will learn quickly.

It's my opinion that metalworking is a science, not an art. That means that if you know what the metal is and follow the proper procedures you should get the same results every time. This is the cornerstone of modern manufacturing.

On the other hand, metalworking is much more forgiving than one would expect from reading the manuals. That's where the art comes in. As an example, while there is a perfect speed to turn a 2 inch bar of 6061 aluminum, you can do it successfully over very wide range of speeds. That's why most lathes have only 6 to 12 spindle speeds. Most small lathes with variable speed don't have a way to measure the RPM so you set it to a speed that is "about right".

You'll find that after a while you will get to know the lathe that you are using and set the speeds and feeds without thinking much about it.

Daniel

 

[precisionworks]

Speed (SFPM) is the easiest variable.

Aluminum - top speed on the machine.

Mild steel & alloy steels - chips should peel off brown & drop blue. No color means too slow, peeling blue or red is too fast.

Titanium (6-4) 100 SFPM more or less for turning or boring, 50 SFPM for drilling, 25 SFPM for reaming. All the feed the machine will handle. Using full flood allows running up to twice as fast where the tool is fully exposed.

 

[tino_ale]

Ok, I'm really having a hard time picking up my cutting tools!
Thanks to this page, I get how the codes can be read, but that doesn't mean I know what to choose :shrug:.

I would really appreciate a "set", if no a whole set, at least a set of boring tools, a set for facing/turning, a set for threading (int/ext) then a parting tool. Buying each individual tool and inserts is going to drive me nuts.
I would appreciate solid carbide tools is the price is not outrageous. I really don't want to buy those things twice, I want to get it right the first time.
I would really appreciate if I could use the same inserts on different tools, at least where applicable.

I've noticed Kennametal "top notch" system, it seems good but I'm afraid of the proprietary system. Should I stay with the standard tool system ?

For each tool I will need aluminimum specific inserts for Al and delrin, and other stronger inserts for titanium and harder materials.

What a mess ! oo:

 

[gadget_lover]

Minimum cutting tooling :
- QCTP PM "kit" =RH and LH cutting tool + straight cutting tool + boring bar+ DCMT/DCGT Inserts or CCGT/CCMT
got it but don't know which inserts I should request

It sounds like you already have a "set". The best bet is to reach out to Matt and ask him what he sent you. The next best is to decode what you have. That's a bit more tricky.

But first a word to reassure you. You do not NEED to use a specific insert for each type of metal. Some just work a bit better than others. Some give a better surface finish or last longer in certain circumstances. In reality, the humble triangular insert without coating has been used by millions of home shops to do just about everything. The super-duper inserts that Will and Will favor will work really well, but you can still do a good job with a super cheap and basic set like this one: http://www.shars.com/products/view/2752/12quot_Indexable_Carbide_Turning_Tool_Set which uses triangular inserts for all 5 tools.


Now back to your problem. The main problem is to figure out what size fits your holders. Each holder is designed for a specific shape (match what you have to the carbide depot site) with a specific way to mount (beveled hole, strait hole, no hole, etc) and a specific thickness. Last but most confusing is the "size" which is measured as an "inscribed circle". All of these are on that page that you pointed to at carbide depot.

An inscribed circle is the largest circle that is totally within the outline of the insert. The size is represented in steps of 1/8 inch, so all you need to do is find the largest circle that fits on an insert and convert that to eighths. I don't have a good way to do that. I have a template for drawing circles that has many circles, so I can lay it on an insert to see what size fits within the outline of the insert. A 1/4 inch inscribed circle is a "2".

The thickness is represented as the number of sixteenths. That's just to confuse the innocent. A 1/4 inch thick insert is a "4".

The clearance angle is the slant on the side. You need a good protractor and a good eye to figure out the angle on a small insert. There are suggested angles for aluminum, plastics and steel. You can get away with being "close".

The rest of the specifications basically are fine tuning. There's a thread or two here that go into those in detail.

Dan

 

[tino_ale]

Thanks for the insight.

In fact I am considering getting my tools separately and not the one supplied by Matt. I haven't decided yet. My thinking is I don't want to get some "okay" tools now and buying them twice because after a month I realize I can get something really nicer at an acceptable cost. That would leave me with some unecessary paperweights and unused inserts. I hate unused tools !

 

[gadget_lover]

Getting them separately can be a good thing. You know how to find the maximum shank size for your lathe and tool post, right?

I suspect that you will get used to having unused tools. You will find that sometimes that 3/4 inch shaft on your favorite tool will not fit into the place you need to reach, so you will pick up some with smaller shafts. Sometimes you'll need to grind a tool to make that precise groove, or to trepan a groove for a spring. Then there will be that itty bitty flashlight that needs a 1/4 inch diameter solid carbide boring bar.

As you can see, the list will go on and on.

May I suggest that you not worry about "OK" vs "the best" tools? The difference is not as apparent as you might think when you are doing work at a home shop. In many cases a proper insert makes much more difference than the tool that it mounts in. The different sizes and shapes are mainly to maximize production rates. Home shops don't need to worry about making 7.5 parts per insert.


Daniel