Finally got the milling machine home.

I looked at the link for the guy manufacturing leadscrew nuts, and I don't think he has any suitable for the L V. I made two X axis nuts out of leaded gunmetal, but it was not straightforward. The leadscrew is 3/4 X 5 acme RH, too small to pass laydown inserted tooling. I bought a tap from Tracey tools and did not think I could produce the thread just using it as the torque required was likely to break the tap. I used a cut down tool with an 8 TPI acme form running at the 5 TPI to produce a partially finished thread. The tap finished it. As cut, the nut had some backlash, but my modification was to use two nuts and extend the leadscrew thread and also even out the wear in the leadscrew threads. My backlash is much improved. As long as your nut still has some threads, you can rely on the DRO for travel. Just remember that climb milling with lots of backlash is not recommended. I could make you a nut if you supplied the bronze, but the backlash would depend on the leadscrew condition. Or I could lend you the tap, which might work if the core diameter of the thread was increased by about 0.010".

Thanks for that old mart. Today I have read your article / thread on the mods you did. On my X axis the lash is .6mm on the Y it is just under 1.5mm So not ideal but with the DRO , not really a problem. I am hopefully going to have a go at milling down the base of a Q/C toolholder by 4mm on Sunday so will see how I go. Was going to try 0.5mm 1st to see how hard the steel is. The others I did in the lathe were murder. 1st few I did with HSS but then I got tips for the toolholders I had & it was not as bad. I even did one with a brazed tipped tool, which I guess would have been carbide.???. Are these cutters any good as it's all I have for now. Regards

Steve.

We were lucky with the Y axis backlash, it was acceptable without any work, just as well as they are LH threads.

I notice that you have a Clarkson Autolock for the mill. To compensate for the flexible MT2, there is a threaded collar, LH, I believe, which is snugged up AFTER the drawbar is tightened. It stiffens the assembly considerably. Be careful not to get imperial and metric threaded cutters mixed up, if the size of the cutter is fractions of an inch, never use a metric collet with it and vise versa. If you are not conversant with using the Autolock, just google Clarkson Autolock instructions.

The cutters will do for a start, keep an eye out on ebay for resharpened solid carbide, up to about 12mm, don't touch them down on steel unless they are rotating or they will chip, and don't drop them ever, and always store them in a tube. 

Edited By old mart on 14/03/2020 20:53:16

This drawing from the Denford Forums shows the TS head and it is obvious why an extension screwed into the bottom of the quill to hold a larger taper roller bearing is necessary if converting to R8.

**LINK**

It looks to me like Steve has a Clarkson S type chuck.
My MT2 one doesn't have the extra left hand threaded collar.

Also it's not suitable for plain shanked cutters, requiring threaded ones of the Clarkson style.

The C type (still a Clarkson Autolock) has a separate collar into which the collet fits, and also has the left hand nut at the top.
Mine works fine with plain shanked cutters, as the extra internal collar closes the tines of the collet.

On the S type, the cutter's shank needs to project backwards through the threaded portion and engage on the pointed centre to shove the collet forwards far enough for the nut to close it.

The C type has two little pegs on the back of each collet to drive it, whereas Steve's S type has two flats.

The similar Titanic, has a half cutout on the rear to provide the drive, but again, can't cope with plain cutters.

Fortunately, it looks like Steve also has some ER collets so he can use plain cutters OK; all carbide cutters I've seen have had plain shanks.

Bill

Maybe in horizontal sure.

I don’t worry about that on my Centec. Thinking is that vertical (plunge) cutting with a vertical mill is one thing but sideways milling can exert as much, or more, side thrust on a 2MT spindle than when used in horizontal - as the horizontal arbor is supported at both ends. Bearing sizes are likely the most important factor? It is only used as a hobby machine, so I don’t (need to) over-stress it.

Thanks old mart but I don't think I am that brave. will take on board all you have said.

Steve.

You can hold threaded shank cutters in an er collet as long as the threaded section does not interfere with the clamping length.

As I mentioned, having already got machinery big enough to do the mod on the spindle is essential. I spent much more time than usual setting things up to run perfectly before cutting any metal and have been rewarded by having a sweet running r8 spindle in the TS.

One mod still to be done is to have a quick change knee handle like a Bridgeport to supplement the wheel. With heavy tooling on the bed, the weight makes lifting the knee very difficult with my arthritis.

If I didn't already have a large number of carbide endmills, I would be tempted to buy these, great value and not at all bad:

**LINK**

I have a set of these same carbide endmills i got from Banggood, very good quality indeed & cut far far better than my branded hss cutters. Brilliant price as well makes them even sweeter.

This evening I have purchased some cutters. Not sure if they are the correct ones. E-Bay seller. Job lot brand new. The makes are various. Says they are carbide.

Sorry more pictures for comments. The large ones not sure how they fit or if it even if possible to fit the up to a MT2 taper. Idea's please. Also got a gallon of this stuff given , any idea what it is for. Smells like paraffin, but oily too.

Steve.

Edited By Steviegtr on 15/03/2020 23:28:06

Merlin 414 Carbide End Mills general purpose 30° Helix, centre cutting, K30, 4 Flute, TiALN Coated £28.95.

Swiss tech ones around £25 each from googling them.

I paid £171 for 50 of them. Works out at £3.42 each. So not bad if they are what I need. I can hold up to 16mm with the ER collets. I only have 3 collets for the Clarksone but no threaded cutters anyway.

steve.

Edited By Steviegtr on 15/03/2020 23:26:57

Sorry gone ahead of myself. I had come on to post that I tried to mill down a 250-112 toolholder & failed miserably. The H.S.S cutter would not touch it. The metal does file but not easily so pretty hard stuff. Hence me going nuts & buying those of ebay. Shd last me a while.

Steve.

Looks like a pretty good haul for £170.

Arc sell MT shellmill arbors (To mount the big cutters on) You need to measure the hole in the cutters to determine what size you want.

They only list 16mm and 22mm in 2MT

Well that lot should keep you going! Per tool, good price.

Not all sunshine though. On my mill (WM18, 1100W, max 2250 rpm), I generally prefer HSS to carbide because the machine can't spin small diameter carbide fast enough for best results. Nor is the machine rigid enough to give big carbide cutters the welly they really need. You'll see much the same because your Tom Senior was designed long before carbide milling became widespread. As a machine it's balanced for HSS, which works best at about 20% of carbide capacity.

Don't worry, carbide will work and although your mill is ½HP, I think it has a somewhat higher top-speed than my WM18. But it's very low compared with a machine designed for carbide. Getting the best out of it is a matter of balancing power, cutter diameter, feed-rate, depth of cut, rpm, and machine rigidity against the material being cut. Lots of variables to cope with, so don't be put off if first attempts are disappointing.

I only have 3 carbide milling cutters. A 10mm 4-flute gets used most because it's good at roughing steel. Although it can and does produces a good finish, I usually find it easier to switch to HSS for the detail work. As always much depends on the job in hand.

The cutters in your set most likely to disappoint are the big multi-tooth affairs:

They're designed to remove a lot of metal quickly. Each cutting edge has to be powered through the metal, which means a big motor and a stiff machine to take the stress. A Tom Senior (or WM18) can't be expected to do super work with big carbide cutters.

But try and see. Although carbide works best at high-power and high-speed, it often performs reasonably well on slower machines and is very convenient (can tackle materials too hard for HSS and reduces need to lubricate and for re-sharpening.)

HSS is usually sharp with fast wearing edges. Carbide, being significantly harder and heat-resistant, is often comparatively blunt. Counter-intuitively, blunt cuts are more efficient than sharp provided enough power is behind the cutter. Blunt removes more metal faster and uses less electricity. Power efficiency is vital to industry, who also minimise downtime when tools inevitably go blunt, and like to increase the scrap value of swarf by not contaminating it with coolant.

Industry often put thousands of watts behind a cutter and expect it to last, flat-out, for several hours. The trouble is many carbide cutters are designed with industrial service in mind, not to suit mid-20th Century HSS machines. Although there are suitable HSS-like inserts, keep in mind Carbide Catalogues bulge with less desirable to us types, some of which are unacceptably inappropriate to our machines. HSS requires much less research, and has good general-purpose slow speed characteristics well suited to hobby metalwork and classic machine tools.

I see you've leapt straight into deep water again by attempting to mill a hardened tool-post. Practice on something easier first! The beginner needs to seduce his new tools, not crack-on regardless. There's more to learning the violin than buying a Stradivarius and having a go at Paganini's Caprices...

Dave

Edited By SillyOldDuffer on 16/03/2020 10:57:11

That may well be true of inserts, it isn't true of sintered carbide endmills. The sharpness of the edge is determined by the size of the carbide particles. They're pretty small these days. When I opened my first high performance 10mm cutter bought from Cutwel I carelessly sliced my thumb open. The cutter made an incision any surgeon would have been proud of; didn't half make a mess - blood everywhere.

Andrew

.

That said ... using either two or three inserts [balanced], and running at high speed, would probably make it a useful tool.

MichaelG.

The facemill people are reposting photos of will be the best of the three to use, the round insert ones will put too much strain on the machine but with the right inserts and a moderate depth of cut the other will be OK, they work on the SX2.7 so should work on the TS. I would have thought dave's Warco would also be upto using them.

The Swisstec may not be such a bargain as the price you quoted sounds like full retail but they are often on special with discount in the region of 60% or more eg a set of six can sell for £25. And they have never been near Switzerland either but likely to be a better quality than the unbranded ones liked to last night. They will work fine on the TS even if run at HSS speeds and cost you no more than HSS anyway, just a little care in handling needed as they can chip.

Edited By JasonB on 16/03/2020 13:26:01

Well thanks for the tips. Yes the prices is saw were from the name I googled. That pointed me at the main manufacturer , which of course would have quoted the retail price. Once they come I will try them & see where to go with them. Thanks.

Steve.

Those larger shell mills with their inserts would be best sold on ebay, as MT2 is far too small to hold them without flexing like a wet noodle. That is the reason for the dampening sleeve on your Clarkson Autolock which only holds cutters up to about 18mm, (16mm or 5/8" shanks).

Apart from them, you have a good lot of useful cutters.

Edited By old mart on 16/03/2020 16:52:41