Thread: Morse Taper Turning

Originally Posted by jvdv

Hi Metal Head,
Thanks for the alternative method. It makes sense to me and I will give it a go in the future.

Milling Operation:
Are you saying that I should be feeding the work into the cutter in such a way that the work is moving in the opposite direction as the direction the teeth is going in?

Dazzler,
In my case I plan to mill (saw/slit) a locking color and some clamps that I plan to make. See attached pictures a bit higher in the tread. I guess you can saw/mill anything that HSS will cut.

Hi JVDV,

Hopefully this link will be able to explain what I was trying to get at in my previous post.

http://www.mfg.mtu.edu/marc/primers/milling/index.html

Regards
David

Hi,Jan,

Convential v Climb milling. http://www.hanita.com/hanita_protected/tec00006.htm

http://me.mit.edu/Lectures/MachineTools/mill/intro.html

I prefer to climb mill, though do not let it get away from you. As David said it can do a lot of damage. Best to wear the brown pants

The mandrel has a right hand thread. The key takes the drive and removes lock/unlock torque from the nut. Why in your case make sure retaining bolt/nut/screw is well tightened.

Regards

Dennis

Originally Posted by cub3

I prefer to climb mill, though do not let it get away from you. As David said it can do a lot of damage. Best to wear the brown pants

Regards

Dennis

Personally I have only ever "climb milled" when doing final cuts on aluminium as it gives a better finish. However it is up to the individual as to how they want to do it.

Regards
David

Unfortunately, I stuffed up the taper that I was busy with. I grind the finishing tool as depicted earlier in the thread, and took multiple passes in order to get a good finish. I did not check the taper diameter on a regular basis, and when I checked the taper was to turned down too much. The finish was also still not acceptable (in my view).

Anyway at that point I gave up and started to move some wood that I have bought into racks.

It would be great if anyone can provide some pointers on surface finish that I can expect and should aim for. I am not getting even close to “near-mirror” like finish that some people on the internet is describing.

Hi jvdv,

Now that it is too small, you have something to practice on.

Ignore books.

Reduce top rake to 1 to 2 Degrees.

Nose radius 1/16" to 1/8". Diamond lap radius after grinding.

Use slowest speed. (I can drop down to 8 RPM)

Depth of cut 0.002" to 0.004"

Hand feed compound slide Very Very slowly.

Use coolant flow.

Another book for you to ignore

http://www.tokentoolroom.com/files/T...%20turning.pdf

Best Regards

Dennis

Hi Dennis,
I like the positive spin that you put on my first taper turning attempt.

I will give your suggestion a go.

My lathe can only drop down to 50 RPM in back-gear.

I do not have a coolant setup, but I will try to put some temporary coolant mechanism in place.

I do not have a diamond lap yet. What grit are you using? I was thinking of getting one. I do have an oilstone and normally use that to finish of the HSS bits.

Thanks for the advice.

Regards,
Jan

Hi Jan,
Sorry not the reply that i want to give, If you have 5 minutes/can escape. set up drop speed have a go any WD 40 will post later.

Best Regards.

Dennis

Hi Jan,

I completely gree with what Dennis has said. The only thing I would add is buy an el cheapo plastic spray container and place any coolant you may have in it and spray it on the workpiece frequently with your left hand. If this doesn't quite give you the finish you want then get some emery cloth/wet & dry and clean up the surface with various grit sizes until you get the finish you want.

Regards
David

Hi Dennis and David,

I was wondering what is the main purpose of the coolant in this finishing operation. Is it for cooling or lubrication or washing the chips away?

I do have a spray bottle that contains a 50/50 mix of kerosene and neatfoots oil. I use it for tapping and it works for me. I do have a can of WD40 around so I will give that a go as well.

The other question that I have is on the finishing tool. I attached a few pictures of the tool that I have ground. You suggest a top rake of 1 to 2 degrees. Am I correct in saying that the tool should look like the one in the pictures, but the slope from the cutting tip to the rear of the tool should be very small. This one is around 30 degrees. I should make a new one which is 2 degrees?

Regards,
Jan

I'm a real novice on my metal lathe, so not really much help. I use diluted soluble oil in a mayo squeeze bottle, and just apply that in a dribble with one hand. Didn't stop me from snapping off a parting tool on Monday though.
As for a fine finish, I've been using a file on the spinning work, as described in several old machining books (including that good link from Dennis, to "Text book of turning"), which would seem a good intermediate stage between cutting tool and emery paper.
I haven't worked out how to taper turn yet, but one day I'll give it a go!

Cheers,

Originally Posted by jvdv

Hi Dennis and David,

I was wondering what is the main purpose of the coolant in this finishing operation. Is it for cooling or lubrication or washing the chips away?

I do have a spray bottle that contains a 50/50 mix of kerosene and neatfoots oil. I use it for tapping and it works for me. I do have a can of WD40 around so I will give that a go as well.

The other question that I have is on the finishing tool. I attached a few pictures of the tool that I have ground. You suggest a top rake of 1 to 2 degrees. Am I correct in saying that the tool should look like the one in the pictures, but the slope from the cutting tip to the rear of the tool should be very small. This one is around 30 degrees. I should make a new one which is 2 degrees?

Regards,
Jan

Hi Jan,

Personally I think the bit you have ground is OK for ally but not mild steel but then give it a go and if it works OK who cares. If it doesn't then grind it to the (angles) dennis mentioned. I would also give it a bit more front clearance. Just ensure the tip is at centre height.

Let us know how it goes.

Regards
David

Originally Posted by Andy Mac

I'm a real novice on my metal lathe, so not really much help. I use diluted soluble oil in a mayo squeeze bottle, and just apply that in a dribble with one hand. Didn't stop me from snapping off a parting tool on Monday though.
Cheers,

With regard to the parting tools: I know exactly how you feel. When I just got my lathe I used a cheap carbide insert parting tool that came with the lathe. I destroyed that one with the carbide being pulled from the tool holder. I then got myself a cobolt/HSS blade that mounts in a clamp arrangement. I was using that for a while without any problems. One day not to long ago, I was parting of a 50mm mild steel bar. All was going well, and then suddenly about halfway through the parting operation the blade just shattered. I think the bar climbed over the blade. The toolholder was also partly yanked from the 4-way toolpost.

I had a massive fright, and since that day I did not attempt another parting operation.

My plan for the future is to build a rear mounted tool post and ask for help with regard to the grinding of the blade. Originally, I just used the blade as it was supplied and that is a mistake I think. The blade comes with a bevel on the top face, and I now think that that bevel was forcing the blade sideways as I was parting.

So until I have build the rear mounted toolpost, I just going to hacksaw the parts on the bench and face in the lathe. If you have any more wisdom on parting, I would be very interested to hear more.

Originally Posted by Metal Head

Hi Jan,

Personally I think the bit you have ground is OK for ally but not mild steel but then give it a go and if it works OK who cares. If it doesn't then grind it to the (angles) dennis mentioned. I would also give it a bit more front clearance. Just ensure the tip is at centre height.

Let us know how it goes.

Regards
David

Hi David,

I did a quick finishing test last night with the existing finishing tool that I ground. Lathe was at 50RPM, I used WD 40 and I put on a finishing cut of between 0.03 to 0.04 of a millimeter. The finish was the best that I have so far achieved. It was almost perfect. The only exception was that in one spot it looks as if the tool digged in, and that obviously left an ugly groove.

I put that down to the tool geometry not being correct. I will keep this tool for Aluminum and grind a new one as suggested by Dennis and use that for the mild steel. I will also make sure that the front clearance is more.

Thanks for all the advise so far.

You had a go, results improved! Good outcome, vast learning curve.
Back later.
Dennis