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: The size and shape of drill holes|
Gun drills are an illusion to me. The trick is to get the balance of the cutting force, from the centre to the outer, so that it want s to stay on centre. So they have support lands etc to guide the drill. The sharpening of a gundrill to drill straight is quite specific for that drill, and material etc. Now days, there is a new very high speed drill, that out dates gun drilling, with a catch. It needs a very accurate spindle, and very high through coolant pressure to work.
Gun drills can be hand re sharpened , but twist drills, some can sharpen them really well, and others not.
The best firm but removable pins, are tapered pins. The reamer can be a simple D bit reamer to a taper that you can easily reproduce. You can also take a tapered pin, and make it into a D bit, assuming that you hardened it of course. Anything from 1.5 deg per side to 3 deg per side does work very well.
|Thread: Mass Production|
Back to the OP, quite a lot of high volume work was done on multi spindle lathes, with 6 to 7 stations. Each station did a particular operation, often with form tools , or gang tools or other tooling that was made specifically for that part being produced. These were either capable of hand loaded and unloaded parts, or bar feed with parts coming off.
Then the other end detail would be done as a second operation, hand loaded into a basic 2nd op machine, or into a 2nd op semi auto machine. The 2nd op machines, don't have the bar feeders on them, and require the operator to activate the start sequence. Most of the USA machines, needed 2 hand to simultaneously button start.
So in your example, without seeing it, the threaded end would be done 1st, then the end with the hole would be done in a dead length stop collet, for the hole and other detail and the final length as well.
I once saw an old WW2 American cam auto machine that was making the 1st part of a .303 shell casing. It was just as it was last used in 1945 when production stopped. It was the last one, that the owners Grand father did not sell off or scrap or break down the set up of. It was as I was told, his personal piece of history. It had carbide tooling that was top secret in those days. Anyway, it drilled, did the hole for the primer, turned the out side, did the inside , the ring groove and parted off, all in 6 seconds. Makes on heck of a lot of noise and fluid and stuff goes ever where. It ran cutting oil, and they had what looked like an old washing machine, that spun the chips to reclaim the oil from the swarf. I was really impressed and they ran it that day for us to see. This was back in 07. Similar to the video, had a super rapid turret indexing, on the inline turret, and the back turret. It had a similar vertical part off , and a front tool that did not index, but profiled. This did the retaining grove.
The shells were not necked at this stage, that was done latter, along with the former for the primer hole final sizing.
|Thread: Is there a new standard for taps?|
Serial taps out here, is the taps that different thread pitch diameter. Yes they have a single ring being the 1 undersize and the 2 rings being the 2nd undersize tap. Usually the smallest thread pitch diameter is on the 1 ring tap.
Most taps will be like M6 X 1 H7 with the H7 being the thread limit range of that particular tap.
|Thread: Cyclone Vacuum Separator|
I just use one of those inline Vacuum cleaner ones. What I like about it, is the clearish container. It is easy to take off and empty. If I suck up a little part, it is not so hard to find.
I used to have a bigger 25 L bucket with cyclone thing. But prefer the smaller unit that is easier to handle.
This is what I have now. My actual one is made by Hoover, this is a knock off, but is the same thing.
Edited By Neil Lickfold on 31/08/2018 10:54:09
|Thread: clocking in a mill vise. Problems.|
I have a selection of bolts and capscrews with thick washers. They are in 5mm length increments. Keeping things clean is a key to consistency when clamping, especially the T slots, so that swarf does not damage the underside of the clamping area.
|Thread: Bench grinder|
I have found that the hole size of the wheel and that of the shaft, is too loose. I suggest either turning a better inner bush, for the wheel, or using some form of tape, to make up the diameter to a better fit. Once the wheel is in position and clamped it will be good. Cheap wheels need the sides dressing as well as the diameter.
|Thread: TNMG1604 Shim|
There are many shims for TNMG holders. So a brand of holder is needed. You can probably by a cheap brand holder for the price of some shims these days.
|Thread: Calling all Kiwis|
Carbiidenz I think is the best there is. Particularly because he will sell inserts one at a time, and there is next day delivery as well. Has a lot of things and runs specials every now and then.
|Thread: Setting a Machine Vice Parallel on the Mill|
A great topic Andrew. I have seen where some use a single (pivot) tennon to adjust the vice on. Like you say , it takes less that a few minutes to set to within 0.01mm over the length of the vice. To get better that 0.01mm over the length of the vice, it needs to be clamped with a reference of some descript.
|Thread: Calling all Kiwis|
he also has spare coils in 1.5D and 2.5D
Very good to deal with. If the order is in by 4pm, it will arrive by courier the next morning.
I could not find spare coils on Jcar website. The V-Coil is German made kit and a very good quality product.
|Thread: Aluminium thread strength|
The BSW thread form is stronger in weaker or notch sensitive materials due to it's radius on the root and crest. The metric and the UNC form, has sharp edges on the crest of the thread form.
|Thread: Are you a Man or a Mouse When Milling?|
The uneven helix angle and spaced fluted milling cutters work really well on manual mills and the mini mills. They are way better than any HSS cutter as well. The face cutters with the positive geometry uneven spaced inserts also work really well on the mini mills. Got a good laugh from the man or mouse video. Using compressed air with a bit of oil works really well for milling , especially if you adopt the full flute depth of cut with a shallow radial cut techniques. All that you need is some way to stop the chip from being recut again, and the cutter life increases quite significantly. If you also have ball screws or some way to control the back lash, climb milling also increase the cutter tool life as well.
|Thread: How to drill holes in ABS plastic without splintering?|
Having support material above and below the part. Negative or dulled off a drill bit like the video is good for plastics. Also withplastic , not too hi a rpm. Otherwise it will want to melt the material. Same for a lot of other plastics.
|Thread: Ring Light for mill/drill|
What a great idea, and really cheap as well.
|Thread: 3-Phase Motor Conversions: Are They All Hype?|
I was told that the motors, 2 pole or 4 pole can safely go to 40% over their rated max rpm.
Maybe you need to get back to them, so that the person who helped you, finds out that they either messed up, or need more training. Possibly take it further up the chain. The local place here in Hamilton, they will set the drive to suite the motor and the application it is being used for. Really great service too. Companies are only as good as their staff.
After setting the motor to the lower voltage option, get the hand book that came with it, and check the current settings, for your motor. From the motor data plate. The drive will generally go from 20hz to 50hz, but is programmable to 400 hz. Don't go over 70hz on the max limit. Some say don't go over 60z,(USA and Canada power frequency). Like others have said, as the frequency drops,so does the RPM, and so does the total power available. Also there is breaking options, and slow down/ decelleration settings. I think mine is like 0.3seconds or something like that, and have the accelleration at the same rate, on the motor start up and shut down.
I am surprised that if you brought the unit as a complete set up ready to run, that they would have the motor not in the correct configuration. I am assuming that your VFD is the 220V 3phase output one, and Not the 415V output one.
I have a microswitch inline on the S1 control circuit. This micro switch I use is a normal closed one, and is opened/broken circuit when the contact is made. It stops the lathe for when I do forward thread cutting. And allows me to turn the switch to reverse to wind back for another threading pass. Really good for internal threads. I have some pictures in my Album with it.
|Thread: Thread cutting with carbide inserts|
So I have an album here, https://www.model-engineer.co.uk/albums/member_album.asp?a=48822
I have the microswitch on S1 one connection. So when the switch (normal closed) is opened, it stops only the forward direction of the motor. Reverse direction still works . I set the VFD to stop in about 0.3 seconds I think, maybe 0.1 seconds. When the switch opens, the motor stops, then I switch to reverse, wind back.and can take another cut. The microswitch is set on a movable stop to set it in the Z distance.
Will add more to the album when I thread cut next.
Edited By Neil Lickfold on 29/07/2018 12:47:03
The problem you have is that the thread needs to be concentric to the taper seat in the head insert. If you make your heads, bore the inner diameter for the thread form, and turn the taper seat angle as well. Then use a small threading tool to screw cut the thread form. When it is mostly thread cut, you can use a tap to act as a thread chaser. If the tap is run just straight down the drilled hole, often the tap does not start concentric to the hole. I also found, that if the taper seat angle is made a very small amount, tighter on the front, over the nominal angle. I make the Nelson taper seat 34.75 deg instead of 35 deg. With the Turbo plugs, I make the taper 60.5 deg included angle. With bearing blue, the plugs will seal on the very front of the taper seat. Some glow plugs the seat is not concentric to the thread form. Those plugs will always have sealing issues. You can also correct a head, by making a precision thread form and use that to get the head insert concentric to the thread. Then rebore the taper seat.
SInce setting up the myford S7 with a VFD and a micro switch to stop the spindle, it has made doing internal threading quite easy, with confidence to internal thread cut.
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