Member postings for Neil Lickfold

The idea of the wavy springs is to put a preloaded amount of tension onto the bearings, but does leave a small amount of movement with a large load. This is to allow for expansion if something gets hot or cold, the assembly does not jam up. The inner sleeve idea is that the pre tension load is determined by the sleeve length. So you can do up the rear nut holding the pully etc, but are not effecting the bearing preloaded state. Quite often the spindle bearings will come with information on the amount of preload that they should be, and the amount not to exceed. I can't remember what the N value of the springs are, but they use them in a lot of electric motor bearing installations.

Are you using any wavy bearing springs in your spindle pack at all? Or any spacers between the bearings?

A very nice project. Be interesting to watch the progress. Thanks for sharing what you are doing.

Drill and Tap the holes after the pieces are carburised, but before being hardened.

Neil

There are machine reamers that have a tapered front end, although not very common these days.

The best way to find the size of your reamer is like what others have said, is to ream a test piece . Sometimes you will get a slightly different size or result depending the coolant used. like a oil or a water based coolant.

I used to put up with a cold workshop. Last year installed a heat pump and it stays 20c all through winter, and cooled in the summer to about 24c Very comfortable. Its the best thing that I ever did for the shop, apart from insulating it. Until the heat pump, I had one of those infrared heaters , it is like standing with the sun on your back. But the heat pump is way cheaper to run, and once it is all up to temp, does not cost alot to keep it warm.

Neil

My Mitutoyo 0-25mm micrometer is now in my home shop for approximate sized parts. It has errors upto 0.01mm in places in the area's that it has been used the most over the years. But at closed it is zero, and still measures correct at the end of it's total travel of 26mm is still correct. But the variations happen at the 8mm to 16mm range. Some is under by 5um(1/2 division) while others are as much as 0.01 when compared to known standards or known sizes.

So what looks like exactly 12mm is actully 11.99 mm so makes for a nice slide fit for a 12mm bearing. No good of it really needed to be 12mm.

Neil

Inspecting micrometers is a specialists job, and requires things like a optical flat and monochomatic light, apart from length stacks that check the micrometer at different positions. There are now newer methods of inspecting the spindle accuracy and the anvil runout at the same time, while it is rotated. But zero is still done with length bars.

Vascomill CSF 35

Has anyone had any experience with this cutting oil ? Or is or has used it? Any feedback is appreciated on this product.

Here is a link to their brochure.

https://www.lastuamisnesteet.fi/wp-content/uploads/2019/07/Vascomill-CSF35-Brochure.pdf

Neil

I made adapter plates for my vices. It has hold down on the front and rear T slots. Then the vice is placed on this adapter plate. It allows it to be placed at spacing other than the 3 T slot positions. It also allows for pivoting easier as well. Not as easier as the swivel base however.

Neil

I have 2 grip true chucks, and both of mine have bellville washers under the screw heads for the backplate to the chuck. One was second hand, and the other was New in box.

Great restoration project. Those marks on the bed are from people hack sawing something off and then sawing nothing striking the bed. Mine came with some saw marks from the previous owners. When using hand tools like a hack saw , or even just changing the chucks, I have a piece of wood I put down on the bed. Just incase for what ever reason there is a slip or a drop of something.

A machined phenolic cage has less drag over the brass/steel/plastic cages. With ceramic balls a full compliment has very little drag, despite the balls rubbing and bouncing off each other. What we have noticed in model engine bearings, is that the ceramic ball requires a different radius to be effective compared to the steel ball setup. The work I did with some bike bearings was that there is a definite gain to a ceramic ball in a bike wheel hub as long as you can keep the dirt out. We lubricated it with a pfpe oil and only 0.1cc of oil was used in each bearing. The oil is to keep the race surfaces from rusting. These were set up in October 2019 for a indoor track bike, and are still doing great. I am fortunate to have a selection of ceramic balls in some nominal sizes, and also in the plus and minus range in about 2.5 micron diameter changes. They measure the balls to 5 decimal places of millimetre. If they are too loose, they do not roll correctly and then skid. Too tight is just friction. I make the full compliment with a small groove that just allows a ball to be pushed into place. In general I use 52% of the ball diameter as the radius for the groove. Sometimes I use 51% if I want less end float on a particular bearing. This is if I am making my own races though. Most commercial races are in the 52% to 54% of ball radius , depending on the design etc for deep groove bearings.

If we replaced our 3 units with the latest Daiken high efficiency units, our max power to run all 3 will be 2.35kw total. Our current system is 2.9kw to run all 3 according to the specs of power consumption. The largest of the high efficiency units is a 5 kw heat pump.

Edited By Neil Lickfold on 09/10/2020 19:40:52

Andrew Binning, We live in Hamilton NZ, in winter it gets to a frost, so no colder than -6 C and summer will get to 30c but with a very high humidity. Out here, most brands are using R32 refrigerant. The system of having multiple split sytems instead of 1 larger unit and the same multi split system is not what the installers reccomend. But there have been some distinct advantages to what we did. Our running costs are lower per unit per room, even with all 3 running. The workshop 2.5kw is set for 22 c heat most year round, except peak of summer when I change it to cool 22c. Having the outside unit so that it gets the least amount of weather on it also helps in my view. We have not had the outside units freeze on us yet. But the combined fin area for the 3 outside units is greater than that of the 1 10kw unit had we gone that way. The neighbours were complaining this winter that there outside unit kept freezing on them. The main cause of the freezing I think was the airflow around the outside unit had some restrictions, ie bins placed beside the unit. Not infront though. Our outside unit is placed on a concrete plinth that sits on compacted sand. We do not hear the outside units running. The units for the workshop are placed at the back of the house where there is a predominant wind blowing through. At the end of that area, it opens to a courtyard and we have the washing line in line with what I call the tunnel. It dries very quickly most days. This breeze that flows though is very helpful to the outside units it seems . The house has large eves, and so most of the time, the outside units are dry. They seldom get wet, and seldom get dew on them either. Our system has a dehumidify mode, which can be set automatically in the program. It does blow the air around and can feel cool as it is dryer air being moved. We changed the direction to blow to the ceiling , and that seems to also work well for us.

We placed our Bedroom outside unit so that it is in the sun, and the warmer side of the house, as we use it mainly for winter heating the cold end of the house. The main living room unit is placed in the cold side of the house, as we want it for cooling in summer, more than heating in winter.

So far it has worked very well for us. We can't see the power consumption for the heat pumps, but the power company we were with, had a home comparison for electricity used based on comparable house specs. Our power bill was consistently 25% to 30% lower than the comparable homes. We do have a well insulated home, but the main difference is we have 3 individual units complete with their outdoor units. The system they wanted to put in was one large outside unit feeding 3 inside units, out here is called a multi split system. The smaller 2 2.5kw units are more energy efficient than one 5kw unit. The lounge has a single 5 kw unit for cooling the space and is the correct size for the area to cool and more than enough to heat in winter. Running all 3 still uses less power than the one big unit.

The 2.5 kw units have a rating of 4.3 and the 5kw is 4.0 the 10 kw that they wanted to put in is only 2.9

Now 18 months later , the newer 2.5kw units are down to 6.5 and the 5kw units are 5, so producing more heat or more cooling for even less energy.

The bearing I took apart had a steel cage. The other bearings had a plastic cage. So I recycled the plastic cage from the old bearings and put them into the new ones. To take apart the steel cage, I use the hook from an O ring pick and starting from the inner side, carefully lift up the cage. It just unfolds the tabs and comes out. I do not attempt to recycle the steel cage. Some of the 15X28 bearings have 10 balls instead of 9. With the 10 ball ones, you need to very carefully distort the outer race, and the centre ball can be removed. The 9 ball ones, the centre ball can be easily removed . In my case the 28mm od race was held in a ER40 collet. The Inner race is held on a 15mm mandrel that is a tight thumb press fit. I made the mandrel from AL. I put it in the freezer and the inner race comes off very easy.

John Hain, what an interesting article about bearings.

I have just done a short and not very scientific study on bearings myself. I have 2 standard 61902 bearings with the plastic cage. Both were cleaned with IPA to remove the oil and spun by hand on a mandrel. They both last for about the same time when flicked to see the time of spinning. One is then taken apart, and the inner and outer races are polished with a felt mop and 1um diamond polish compound. The bearing races really do shine after the felt mop. Re assembled and tried to measure the difference in clearance. With a micron dti was unable to show any difference in total bearing clearance. Both seemed to measure only 0.006mm total clearance. The first thing I noticed after cleaning again was the reduction in total noise from the bearing. The polished one was definitely a lot quieter. The standard bearing still spun for the similar time frame of 10seconds, while the polished one consistently was spinning for 15 to 16 seconds.

Generally ratio's for boring bars are kept under a 5d ratio. So a 10mm bar will be kept to under a 50mm length of working area. As the length to diameter ratio gets longer, the more difficult it becomes to get a good finish etc. Lots of things come into play as well. Sharpness of the tool, the radius of the tool and the depth of cut. Sometimes boring the full length is not the right option.

I just bought a set of Sumitomo anti vibration dampening boring bars.

They have a tungsten weight that counteracts against the vibration being produced . They do work very well. There was an introductory offer on them out here, so got a set.

Other companies also make anti vibration boring bars as well. Some like Mitsubishi ,have their dimple bar series, and others have various ways of adding tension to vary the bar frequency.

If you go to a smaller 0.2 radius insert, it will get rid of a lot of the vibration and has a reduced tool pressure when cutting. For best results with boring bars, you actually want them about a thou or 2 max above centre height. When on or below centre height , the bending load on the bar, makes it take a bigger cut. When slightly above, the load comes down to the centre height and has almost no increase in cutter load. Technically it is reduced by a smidgeon depending on the diameter of the work piece.