Here is a list of all the postings Neil Lickfold has made in our forums. Click on a thread name to jump to the thread.
|Thread: Batch turning small parts to tolerance|
When I was making a series of parts with a thread and a 45 deg taper that was a fit to another part, I made a series of tool stops. So I faced the end of the bar, then tuned the Ø6mm length based on the tool stop that touched the end of the part. Then when the diameter stepped up to 9mm , the length was on the step of the tool stop,and again touched the end of the work piece. The final diameter of 13mm and and allowance for parting off, was the last step in the stop bar. So it is progressed a bit like a wood workers tool. The taper turn tool had some of the material removed already, and again had its own tool stop that referenced off the end face of the part.
It worked really well, and is only as good as the stop is set / made. The down side is if the radial distance is too close, it becomes not a very practical of an option.
The Parting tool used a stop as well. When the part was at about 3mm to go, the stop had worked its way off the diameter of the end detail, so it was free to fall and not jam up on the parting tool. My lathe does not have DRO. From batch to batch, these parts were quite accurate. As long as there was no swarf on the end face etc, and no pip at the centre. I normally where ever possible, leave a centre drill spot on the end faces. That way the tools never have to turn to zero when facing, Makes all your tools so much longer , on harder materials for sure.
It looks to me , that part can all be made using a MDT , multi direction Turning tool. Looks like a parting off blade, but has side clearance to be able to takes cuts left and right. If both ends are the same diameter, you can plunge cut the outer end, then go in to the 1st shoulder length and cut to finish diameter and traverse out. Skim the od, then plunge cut the back shoulder, and the remainder of the back material, then part off.
Without knowing the stock you have and material etc. But with the above approach is quite easy on a Myford, If you have decent digit read out, it will be even easier.
Keep in mind, that with most digital readouts, you need to be still going in the same direction every time to get really good results. A bit like taking away the backlash on a lathe nut.
|Thread: ER32 Collet Chuck|
So, if you now have it correctly registered on the spindle nose. Also you have re turned the inner 8 deg taper per side. If this is correct, then the next area of error is the thread for the nut. If the thread for the nut is not concurrent to the 8 deg taper, it will not work correctly either. The thread will be a 1.5mm pitch thread. So can be recut again with care.
Then you have the collets and collet nut itself to sort through.
As simple as the ER system is , for it to work properly, it all needs to be concentric and true.
|Thread: New collets. Bankrupt now.|
When I do up the ER series bigger than ER16, I do it up with a tap with my copper block on the end of the spanner. Then I put the spanner on 180 deg and do it again. Sounds silly I know, but I have found this to create the most consistent results. Another company that make really good ER series collets, is the Big company from Japan. But their collets are over twice the price of the Regofix ones. I do find that the C spanner does not do the initial tighten to be as good as the mutli tooth ER spanner. However, when tapped from each side 180 apart, they seem to be the same result. I also found that some ER nuts are alot better than others for getting a consistent result. The Hex nut on my ER20 spindle, seems to be very good, even if only tightened from one side. A bad nut can cause a runout of 0.02mm easily , when a good one will result in a runout better than 0.006mm easily with the same collet and test piece or cutter. The part I don't fully understand ,is that the bad collet nut will often have the same run out at the nut face, but measuring the bottom of the pin, so like 30mm away, is where the differences are really noticed. The pin can be tapped to run true, but my thinking is, if it can be tapped true, it can chatter out of true as well. I have not found a Bad Regofix nut yet. The cheaper copies have definitely been the ones I have seen issues with, especially the bearing nuts.
|Thread: Ball bearing spindles|
What you really want in a spindle, is a bearing where the inner and outer race and the swash of the race is as true as possible. There are tables for the precision that the outer and inner race is made to. Now sometimes you can pick up a standard tolerance bearing with its concentricity as good as a spindle grade bearing. But that is very rare.
|Thread: VFD recommendations|
I bought Eric drive VFD made by Rich electric. I only got this as the company that I got the replacement 3ph motor from sells them. Told them what I wanted to do, they matched the settings for my application, and then showed me where and how to adjust it. Like the ramp up or ramp down, start and stop. Also how to connect the microswitch for the stop with the carriage in the forward direction, etc
I have a few more now, and are very happy with these.
a picture of my lathe set up is in my album.
|Thread: Measurements from the past|
In Western PA, North of Pittsburgh, they use the term mills for thousands of an inch. Until then I had never known it to be referenced to linear measurement, but to volume like cc. As to its origins have no clue, but what has been mentioned does seem very feasible. I think James Watt made micrometers in 0.001 inch graduations in his time. So it has been around a while.
|Thread: Emco Compact 5|
The compact 5 is a home hobby mill. Not an industrial power house. But many fine parts have been made on one for sure. It's more set up time to mill stuff etc, but great fun, and very easy to set up from turning to milling. Like a lot of thing the accuracy comes from preperation and thinking about how you do the job. Depending on the accessories you get etc, but on a friends one, he can turn a part, transfer the chuck to the rotary table and then do the milling work, then back onto the spindle and part off the workpiece with everything done at the same setup. So some advantages there for a small number of parts. Like any machine if looked after will last many many years.
|Thread: Gatwick Drone 'Attack'|
My friends fishing drone, can take a 1Kg Payload, fly 500m off shore at 20m atlitude, then drops the baited hook set, and fly's back and lands on the 2mx2m blanket that it took off from. It can be programed to have a higher return path, or the same height return path.
About the only way to safely bring down a drone is concentrated lasers. Some are pre programed now. Not controlled at all from the handset/ controller. Some use a GPS, or use the handset/controller for a reference position. There is no constant signal going to the drone, like a regular RC plane or the early controlled drones. So you cant just easily find the person controlling the drone, depending on the size and type of course. Yeah a drone into an aircraft does have the potential to do real damage. Firing projectiles at drones is almost useless , with a high certainty of what ever you are firing at the drone, also ending up where you dont want these pieces to land. Being as it is an airport, Lasers are the best solution, and should target the drone a safe distance from the runway as well as a known no fly zone. So drones near the vacinity should be automatically removed, and destroyed.
Governments have no clue for laws, as they themselves want and need drones in modern warfare.
|Thread: turning hardened steel|
If you have the TNMG16 tool holder, and get a tngg160402r-s pr1125 insert from Kyocera.
Another good insert is CCGT09T302MP-CK for the 09 holders or the smaller 06 insert CCGT060202MP-CK I have the tnmg16 holders and the ccgt06 holders and inserts.
These inserts will cut steel to 60 Rc at 30m/min surface speed and feed rate of 0.05mm /rev (2 thou) and a depth of cut max at 0.2mm Ø0.4 and finish passes at Ø0.05mm at 400 rpm to 480rpm . Use cutting oil or coolant.
If you have the 1/3 hp motor you may need to make the cuts at 0.1mm deep Ø0.2mm but keep at the 2 thou per rev feedrate.
These inserts can handle the interupted cutting as well.
|Thread: DNMG110408 & CNMG090308 Inserts|
Ron, the inserts that appear blunt work by generating a lot of heat, and plasticise the material. This plasterised material then shears off the stock, with the majority of the heat going into the chip itself. For this to work, it needs surface speed, and rigidity , and a reasonable depth of cut, anywhere from 50% of the tool radius and higher, or the nose radius of the tool in diameter as a minimum cutting depth/pass. Also the edge of the insert has clearance of around 5deg to 7 deg from the radius edge looking sideways.
Your brazed blanks came most likely with 0 to very little side relief angle on them. If you try and grind them on a green wheel, under a microscope there will be micro cracking of the edge and top surface. This micro cracking does not lend itself to very good cutting and shear and surface finish. If you diamond lap the edges, by hand very slow, but a diamond lap wheel is quite fast, the surface is very good and so becomes the surface finish.
For a lot of home / hobby lathes, the Aluminium grade carbides work really well on steel as a finishing tool and can take quite small cuts. The Al inserts do not do well when facing to the very centre, so where possible, put a dimple on the very centre to eliminate that part.
I have given up on negative inserts with my myford and now use ground positive geometry inserts , like the wonder inserts etc
|Thread: Removing Grit after Lapping Ways|
What lapping grit did you use? Like been said scrapping or flat filing will help. Stones and lapping compounds seem to always embed into cast iron. Unless it is hardened. Seldom these days is the cast iron hardened anymore. If soft iron, it is best to just re scrape the surfaces. Things like break clean and microfibre cloths do help. If you see black oil coming from the slide, you know that there is still some abrasive working in there somewhere. Ground slides can have the same issue, particles caught and embedded into the surface. Especially from a fresh dressed wheel that has not been cleaned correctly after dressing.
|Thread: DNMG110408 & CNMG090308 Inserts|
Those insert sizes work just fine on small lathes. As for the actual inserts I cant advise without more info on them.
|Thread: Arc Euro ER16 runout|
I have spent a considerable amount of time looking into errors with the ER collet system. MY conclusions are , if the collet itself is not concentric everywhere, then the errors seem to multiply and get worse. The ultra precision collets are worth it in the end as the tooling does work better as it is held more concentric. ER collets should only be used with parts or cutters that allow the entire length of the collet to be engaged in the collet as well.
Another issue is the concentricity of the thread on the outer body to the inner 8 deg taper, and then the concentricity of the inner thread of the nut to the 30 deg taper. Errors in these, will prevent the collet from correctly locating and being concentric.
I have trued the inner 30 deg taper of the nut, by locking the nut onto the outer with a sleeve. Then made a chisel looking boring bar to just clean up the inner 30 deg taper. In my case a screw cut the M50 thread and then turned the shoulder in the same setup. I had made the sleeve 1st. This has corrected the cheap nuts that I brought. The other nuts with the rotating inner are junk and I found no simple way of correcting these. They will only be to about 0.02mm or so for concentricity . Yes they can be tapped to knock the item into alignment. The RegoFix 1 piece nuts with their low friction coating is concentric to better than 0.005mm when tested on my correction fixture. Did not use a better dti at the time. The cheap 1 piece nuts were out by about 0.03mm aprox. After correction, and using the good collets, a part or cutter can be held and be better than 0.01mm for concentricity all the time.
|Thread: 3 phase vs single phase|
The motor draws the most current at start up. So with my Myford and its VFD, I leave it running in between if making lots of parts. I really like the variable speed the VFD give me, as well as the controlled motor start and stop. With mine the stop can be controlled and take place over a range of program time. Mine is set for either .1 or .2 seconds, cant remember now. It also allows for near instant reverse, just like a regular 3 phase set up does. But because it has a program start and stop, is not as harsh.
Given the choice of full 3phse and VFD, I have chosen VFD over the full 3phase.
I can have a micro switch and stop the motor and feed position when screw cutting internal or external threads.
|Thread: Thread Wires.|
|I still use thread wires but only when I have to. Now that I have a thread mic set to 2 inches I use that most times.i put white grease or vaseline on the wires to hold in place. The plastercine method is only good on small stuff. You would think that the vaseline would make the wire measurement wrong. But no it's just as accurate as if it was dry.the main reason for measuring the thread is so you know what it is for a replacement. As been said, often the mating part is not easily accessible.|
|Thread: Cheap carbide inserts - where's the market?|
The largest cause of insert early failure and chipping is turning to the centre. So where ever possible, just use a centre drill to remove the very centre, unless the part does need the flat face.
I have come to the conclusion that cheap inserts maybe the reason so many think that HSS is still very good. With good inserts, you do not need super fast feeds and speeds like what used to be required 40 years ago with carbide tooling. The newest inserts cut pure copper and leave like a mirror finish , and then you can cut a piece of HSS and turn down the shank to fit something else. With the same insert. With the hard HSS, it will be cutting at 15m/min surface speed, so a 10mm pin turn down to 3/8 will be done at 400 to 500 rpm at afeed rate of 0.05mm /rev or 2thou.
They also last a very long time. The market for cheap inserts is accountant based companies wanting always the cheapest things.
|Thread: Blackening steel parts|
I use the hot bath method. It runs at 135 to 140 C. So some care is needed. It works very well and I have never had any issues with it all. The downside is the time required to heat the bath, and the cleanliness of the parts. Some steels with high chrome content do not blacken very well with this process.
It is cheap to set up though and the basic formula is very simple. My current bath starts with 10 deionised water chlorine free. Chlorine free is important. 10 L of caustic soda pearl, or alternately 10 L of concentrated caustic soda solution, Mix water and pearl very slowly adding the pearl. Ready made solution does not need any extra pearl add. Then after it is close to room temp add 10 l of sodium Nitrite powder/crystals. Mix etc, use care as this is very caustic. Slowly heat to 135C or untill it just simmers. Stir often. The parts will take about 5mins for small sections (less than 25mm thick) to 15mins for 50mm sections) . Remove from the bath, let hang and drip off, then wash in hot water and I use vinegar water to neautralise the basic solution. Dry and oil. All done. This is really a more commercial set up, but does work very well. There are slight adjustments to the basic formula, like adding sodium Nitrate, and some add other stuff as well. If you have a set up in such a manner that you may drop and splash parts into the hot bath, then your set up is wrong. It needs to be arranged so that you can not make any splash of any kind , no matter the reason. You do not get a second chance with hot caustic things. But I am happy with with I have, have been since 09 when I started doing this commercially. Do not allow any non steel parts to contact the bath either.
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