Member postings for Neil Lickfold

Is there a bulging cap in the picture on page 1 ?. If so, I recommend you get it looked at as well.

Neil

A2 tool steel makes for gudgeon pins, and can be flame air hardened and then tempered.

Neil

I replaced the Hard jaws on my Vice at work 16 years ago. I made them from 2 offcuts of electrical copper plate about 16mm thick. Still there and have lasted surprisingly well. They really should be taken out and refaced.They hold work pieces very well and so far have never damaged anything from holding it in the vice. 3 others have since switched to the copper jaws when the copper was available.

Neil

I recently brought some insize digital calpers, a 150mm and a 200mm.

They came with individual test certificate, showing the internal error to 10mm id and the various error over 0-50 50-100,100-150, the 200 goes to 200 on the testing. When comparing to slips, their test coincided with the slips and corresponding error. The reading error over the range was as much as 0.03, but if you know the error can then compensate for it. I have never seen such a test cert with other calipers.

A ball bearing is a good test,as the od and the id of bearings are well within 0.01mm which is usually the resolution of the caliper.

Neil

Keith, how is the mill after the replacement part was installed?.

Neil

The chuck if new is a bad one. With different sizes of stock samples 6,8,10,12,16mm , an error or difference of 0.05mm is inside the normal range for most chucks these days. I have noticed that there are some very cheap chucks coming onto the market that are just not up to snuff at all. Tightening the chuck on the marked or zero key does make a big difference. Sometimes the best key position for the chuck is not the marked one. So try each key position and see if that improves it at all. But I still suspect it is a dud chuck.

Neil

They make one for cutting steel, but are considerably more money than the one sold for wood cutting routers.

Neil

You can cut the threaded end off an old cutter, and then get a plain shank cutter and hold it into the Clarkson type holder. Works very well. There is also a very big range of the ball nose cutter geometries available in the plain shank tools.

Neil

A lot of the automotive splines are not cut with a conventional cutter at all. Your only chance is to take a casting of the existing spine, slice the casting and make an image on a shadowgraph. With a 20x or 50x lens. Then get hss or carbide and make one to match. You can find rollers or pins that fit into the existing spline as a comparator like measuring threads, but your measuring splines. Neil

Threaded cutters are now a special item out here. The reps I deal with do not stock any threaded cutters now. Only 1 supplier that I know of has them and they are more expensive than a coated solid carbide cutter up to 10mm diameter. With the clarkson, I used to have a set of threaded ends to make the collets be able to hold non threaded cutters. Never had one come loose or let go. But now they have a full set of R8 collets, so just use those instead most of the time. The Clarkson is handy when you are drilling some holes or change back to milling, the the table or head height does not have to be adjusted so much.

The ER series work well, but the tool really needs to have 90% or better length location into the ER collet, or else they have a tendency to clamp harder on the back of the item and in turn leads to the cutter walking out of the collet.

For the smaller diameter cutters, I like to use the smaller collet series. As for the sale price on an AutoLock setup, the 2nd hand market for them is a joke. Especially when you consider the quality of the AutoLock unit and how well made they are and what their new price as the time. But that must be a sign of the times I guess. I have an Autolock, but won't ever sell it. For the odd time that I do use it, is worth the shelf space.

Neil

What I have found is the positive rake ground carbide inserts for Aluminium works very well on steel with my myford lathe. I just do not face across the centre on steel with them. I normally if the part allows put a small centre spot to take away the very center point. I use the TNMG 16mm ground Ali inserts, there is anew one out that is coated for stainless steel, looks similar to the Ali one but instead of being just shiny is a purple brown colour. The local rep call them the wonder insert. They are just the nuts at the moment, and he sells them as singles for the hobby market. I have the 0.4mm radius and the 0.2mm radius. I use the 0.2mm rad insert the most. Unless you do something stupid, they last a long time on mild steel and low tensile. The harder the steel the shorter the life of course. The 6 cutting edges make them cheap per edge compared to the dcmt or ccmt geometry inserts.

I used to have hss all the time.But am a convert to the insert tools on a hobby lathe. Hss is in it's own for 1 off special shapes or low run form tools so still has it's place.

This is a link to his site to give you an idea.

http://www.carbidenz.co.nz/store/index.php?dispatch=products.view&product_id=2194

Neil

Where ever possible, we use the max flute length for cutting. As a general rule use only 10% of the cutter diameter as a cut width. If you have less power then the side cut amount will be less. This is side cutting, not trying to make the initial slot. The cutters get reground on bottom face and side faces if they are worn/not sharp. Where possible I like to put a small radius on the corner of the cutters, they chip less and therefore last longer.

It is also called adaptive machining these days in industry.

Neil

Edited By Neil Lickfold on 12/04/2015 01:50:42

To make a guide , use either square or round stock, what ever will fit inside what you are drilling. Drill/ream/bore to suite the drill you are using. After drilling through the 1st, then put the guide into place. You will needs shims and clamps to support, or else you make a external packer to support it. You will know when it is correctly aligned as the drill will spin freely. Then drill the next hole and repeat.

Another way is to make a hinge drill jig. Like it says, it is a piece that had been drilled though and cut away or made up of segments like a door hinge,1 side only. The drill goes through the 1st hole of the hinge, the ist drilled hole is in the space, the drill goes through the second hinge hole as a guide, the last gap is where the part is being drilled.

It all depends on your drilling set up etc as to how it can be achieved. Long centre drills can be easy 0.1mm off centre.

Neil

John, they now sell cutters that are deliberately undersized. Like a 15.7mm for a 16mm slot. The idea is that it makes a pass through the middle, then cleans up each side.

We always measure the cutters for anything accurate, and do the final finish pass after measuring the part. We compensate on the cutter diameter info in the tool library.

Neil

The only issue I see with the ARC sharpener, and maybe it does or does not , allow the resharpen of variable pitched cutters. They have been around a few years now, in 4 and 6 flute geometry.

Neil

Making an alignment drill guide is another way, bit more time, but more guaranteed alignment.

Neil

What sort of lathe do you have ? I have a couple of tailstock turrets. A smaller one with the indexing on return and another that you manually index. The tool hole does not align dead nuts. It is a little off centre about 0.03mm 0.05mm TIR actual. Since the tailstock is actually 0.02mm above centreline , it is only about 0.01mm out, .It runs true to the axis of the quill, so have found the correct radial position that is the very best alignment. I just put a marker pen mark on the back of the unit that I sight by eye through the 2 oiler fittings on the tail stock.

Neil

You have made some very good points. I have 1 meter to the wall at the tailstock end, and the headstock end is 1 m from a door. I can put a bar into the lathe and make up a makeshift steady to support the bar, like a home made bar feeder. On the underside of my little tool cabinet on the wall is 2 strips of LED lighting. It runs off a 12V transformer. It puts out loads of light, runs the full length of the lathe.

Neil

So, what is the geometry that allows a drill to be able to drill 1000's of holes ?

Are there any pictures for this geometry ?

Neil

Since I have installed the VFD, with decelleration at 0.1 seconds, I now screwcut at 200-400 rpm. depending on pitch. The 0.5 to 32tpi is around 400 rpm, but 1mm and 1.25 I slow down to 200 rpm or so. I always have a runout area when threading. I look at the hand wheel position, and turn it off when I see the reference mark. It is very consistent system for me. I often stop within 0.2mm on the wheel. I dry practice if I have not threaded in a while just to get the timing right,especially on internal blind holes.It is not for everyone not looking at where the tool is to stop a lathe I must admit. I had an idea to put a microswitch onto the saddle. Have all the bits, just have not mounted and installed it yet.Neil