Stuck Morse Taper in Warco Major 3024YZ

Thank you, I shall, I'm grateful and a bit overwhelmed by the explosion of responses.No luck this evening,, tried drawing it out with the collet nut. I haven't run the machine yet so got about giving that a go before rigging up some wobbly milling setup. Plugged it in, pushed 'forward', and nothing. It turned out that there's a post, which I think is meant to hold a guard, which was interlocked. I didn't get the guard so bypassed it and now it's working but it's a bit late to continue exploring. Fortunately my electrical knowledge exceeds my mechanical.

I use a cheap stainless steel "thermos" Just replace the stopper with a foam plug including a vent hole.

Robert G8RPI.

I certainly hope that people considering buying a new mill read this thread right through before choosing a Morse Taper spindle. These threads repeat several times every year.

Nothing wrong with a morse taper. The user just needs to be aware of the operational requirements and actually follow them. There have been no stuck tapers in my workshop - except when I put a cold taper into the warm spindle on my lathe. No real problems, otherwise, and that one was extracted quite easily with a little thinking outside the box, as I recall. The main problem at the time was that it was a reducing sleeve with nowhere to use wedges.

My wedges are now linked as pairs - and easily found hanging on a hook on the wall.

That these threads repeat several times every year just shows that some do not read these threads, or just have no idea/experience of operating machinery. Morse tapers have been around for far longer than the R8, which old mart clearly prefers - or maybe he doesn’t know how to simply and safely remove morse tapers?🙂

Question: Does anyone know of a hobby lathe with other than a Morse taper, if provided with a centring option in the spindle? My lathe has one (MT4) and has had it for over 50 years.🙂

Look for any signs of heat discoloured metal on the morse taper socket.

By the amount of force used already it is possible that the mill has had the cutter stop and the spindle spin on the morse taper long enough to get red hot and when stopped has welded them solid.

More likely the pervious owner used big long spanner to winch up the drawbar way too tight.

Insert the morse taper of the tool half way into the socket then slap it firmly home.

Advice I was taught Use the correct size spanner on the drawbar,

Hold the spanner in your fingers put your thumb on the spanner at the centre line of the spindle.

The amount of torque applied with the fingers is enough to hold the drawbar firm.

Totally agree, never had any issues with them apart from the one I posted because the previous owner had put a tangless sleeve in the tailstock.

Martin P

The R8 taper was developed for milling machines and is self-releasing, the Morse taper wasn't, and isn't.

Andrew

I’m guessing R8 wasn’t around when my Centec 2B was manufactured. I don’t see many old mills with an R8. Mills have been around far longer than R8, so when were these fittings introduced?

R8 was a Bridgeport thing originally. So probably started when they did about WW2 era. Then spread through the ubiquitous clones to the general population.

A drilling machine which uses Morse taper usually has an extraction slot for a wedge to remove the tooling. Very few mills have this feature, unfortunately. Morse taper mill fans are always people who are stuck with one and try to justify its shortcomings by telling potential mill buyers it is perfectly satisfactory. I repeat, as usual, if you are in a position to choose between Morse taper and R8, go for the latter.

People fail to understand that a MT drawbar doesn't need to be cranked up to 70ftlb.

Try doing the same thing again. Leave it for a while under pressure then, still under pressure, add more force by giving the drawbar a clout. Also more force can be added by givng   the collet nut spanner a good clout to create a shock load.   Colin

Edited By colin hawes on 19/08/2022 12:18:31

^^^^ THIS.

I think maybe some of the confusion arises out of R8 vs Morse. R8 is a self releasing taper, so a good heft on the drawbar nut helps snug it up nice and solid without causing the taper to jam up.

But the same heft on a self-locking Morse taper is A. totally unnecessary as the taper does the driving and retaining with the drawbar there as backup when side impacts temporarily jar it loose and B. pulls that slow taper up into the socket until the molecules in both are sharing electrons and chances of getting them to separate are diminished by the square of the force applied.

Light side tapping will assist.

Tony

Early Bridgeport heads, for use on horizontals, offered a choice of Morse or B&S tapers. I think the R8 taper was introduced in 1938 during the design of a completely new milling machine, which became the Series 1. All three rely on the taper to transmit power, and so are limited in the power that can be transmitted. The concept of the 7 in 24 steep tapers, such as the ISO series, for milling machines was first patented in 1927. With these the taper is for location, power is transmitted via seperate drive dogs.

Industry moved away from self-holding tapers in the 1930s as milling machines became more powerful. The R8 taper is only popular due to the success of the Bridgeport Series 1. Two of my milling machines use R8, and the third is ISO40.

Andrew

If you are going to hit it again please arrange some packing between the bit with the female taper and the table. Putting impact loads through the spindle bearings is not good

If a lathe is available, I suggest making an aluminium or brass sleeve to be clamped up with the collet nut as before. It needs to be good and solid, and the nut tightened once again as hard as possible. If it only catches on the spindle by a little, make a steel support spacer and split it with a saw so that it can be fitted to support the sleeve, and both clamped.

Now run the spindle slowly, and heat the sleeve with preferably two blow torches to something like 250C. It needs to be as quick as possible so that only the sleeve gets hot. This should produce expansion of 20 parts per million times 200C – about 4 thou per inch. A medium thump on the drawbar at the same time is worth a try.

Thanks, I have a lathe, a very old drummond. It's a bit of a chore to use and it's 3/4" spindle thread limits it's duty a lot. With patience I could make this out of brass or aluminum. I've also got a Smart and Brown Model A, which I imagine would do this in a blink, but it's not running yet.

I've started milling out the plates to make the wedge as suggested by other posters. This is my first time on a mill so taking things slow. I've squared them up, with the drawbar loose, and it hasn't dropped yet! Ready to put the taper on them now, have to work out how to hold them to get a repeatable angle.

Hi Duncan,

Thanks, I am worried about the bearings. I would really rather not have my first experience with a mill be to strip the spindle and change the bearings. I've only run it up to 300rpm so far and it's happy there, but can go to 2000rpm which I imagine is quite different and damage to the bearings would be much more apparent.

The collet holder diameter is about the same as the spindle nose which makes it hard to get any support in there, once I have these wedges made up I can at least use them to support the spindle while smacking it.