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: Exploding Grinding Wheel|
What surprises me, is that new grinding wheels are sold, with no instructions about crack or ring testing the wheel. Broken wheels don't happen all that often, but only once is too much. Last year a friend went to start a cylindrical grinder. It had a newly mounted and dressed wheel the week before that was ring tested. It broke almost perfect in half with the two pieces flying out like a brake drum shoe set. The motor stalled and the fuse failed all before he hit the e stop button.
As an apprentice we were taught to stand to the side of the grinder when starting, and be on the side of the main power switch or wall outlet. Wait a few seconds, then use the grinder. Never stand directly in front on start up. All the wheel failures I have seen or heard about have occurred during or very shortly after it has got to full RPM on start up.
|Thread: My new Sieg SX3.5DZP problem|
There may well have been a primer paint issue. See it from time to time with cars as well. We had an Alpa grinder that a paint issue. The paint came clean off the steel. It was stripped back to metal and re filled and primed then repainted. The repaint work like any good paint should have. The primer was called PA10 etch primer. May be a banned paint these days. It was a rust red colour primer. The finish paint was a 2 part paint, but not a car paint. It was sprayed on. I was told that the car paint was sensitive to the coolants etc and the machine paint stood up to the coolants better. For some reason I thought it was an epoxy paint, not a cyano paint like the cars use.
|Thread: Stroboscopic effect|
I once did a job where we used a strobe light to freeze the work piece so to speak so we could more easily see the detail being turned. It worked a treat. But had it only turned on for the duration of that part of the work piece. We latter did some fun things like looking at the way the swarf was coming off the boring bar etc and the strobe was adjusted to be able to see these sort of things. This was back in 1990.
|Thread: The fit of tapers|
Actually the incycle variation on a single cylinder 2 stroke engine is very real. Using light weight materials for the disc will be in your favour. The advantage of a driving taper over a shaft and keyway , is that you can make adjustments to the opening or the closing while maintaining the same total induction duration. A good way to make these is to make a set of gauges, male and female. These can be used to make the shaft the correct taper size and the other to make the hub the correct taper size. If at any other time you need another hub for a different plate, you can just swap them out and see the difference in performance and swap back without too much fuss. Taking your time and being careful there is no reason for you not to be able to achieve a 0.05mm linear position on any of the interchangeable parts you make.
Anything less than 8 deg per side is a locking taper, from 10 to 15 deg is a driving taper that is releasable. On a 10 deg per side taper, for every 0.02mm in diameter the shift is 0.11mm in height. For a 15 deg taper , every 0.02mm in diameter is a height shift of 0.075mm .
With care and gauges, on a 10deg taper, you can get the height to be about 0.02mm , depending on the diameter of the parts and the preload amount of course.
After you go past 20 deg per side, keeping the swash correct becomes more difficult along with the alignment of the two tapers. 15 deg per side is a good place to start as that is much easier to set the height offset compared to 10deg per side. 10 deg per side has a higher tendency to drive how ever, less likely to slip.
But nowadays there is a collar system that clamps onto a shaft and holds a pulley. They slide together and have a very strong transfer of drive or torque. This may be another option as well.
|Thread: DIY quill stop for Bridgeport mill|
I like it.
I have made some tubes of differing lengths that fit above or in between the setting stop. So have some for the counterbore tools and for drilling etc
I like that you can Rotate it to fine adjust the height was well.
|Thread: Balancing IC engine|
The important part is that the crank will sit a 12 o clock in line with the cylinder when vertical. As for the ratio that changes depending on the application and cylinder position. Some motor cross engines were balanced as low as 30 percent when the cylinder was pointing forward. This gave very little side ways or vertical vibration to the rider. F2C diesel team race engines are between 30 and 40% balance, as it makes for a lighter over all engine. It seems that the underbalanced engines are the ones with better range on the tank of fuel. The balance when from 30% to 60% aprox, when held in a very firm mount, will produce the same amount of total power on a test stand. But in a model however that number can vary hugely depending on how well supported the engine is held. In some situations it is preferable to have an engine that has more cylinder in line out of balance and less side ways induced forces.
|Thread: Floating Reamer Holder|
A really great idea. Thanks for sharing.
|Thread: Interpreting these bearing blue patterns|
You blue is too wet to get best reading results. Put some blue onto a paper towel or a piece of printer paper. The paper will wick away the excess oil. Then you will get a much better read of where to scrap. As you have it, it can wick to an area and create a false impression. You are on the right track with taking off only on the very tight spots.
|Thread: How to cut a tri-lobe bore in a change gear (Schaublin style bore)|
There was a youtube video on drilling square and lobbed holes. It had a template that the tool followed and that inturn generated the shape hole.
|Thread: ER32 COLLET SETS|
One other option, is to make your own. Requires a lathe and a method to slit them, and debur afterwards. Pre hardened steel around 40Rc like 4340 steel bar works great. Can still be all done with hss tooling if you don't have carbide, and can be slit with a hacksaw or junior hacksaw if you don't have a mill with slitting saws.
My best collets are the regofix high precision ones for my ER32 collet chuck. The best nuts are the Regofix ones as well. As far as tightening goes, the regofix have a special coating on them, called the Hi Torque series. I use a bearing one at work as they wont spring the cost for a regofix brand one.
It is important that the thread of the chuck is concentric to the inner taper. The cheap nuts I bought are junk. Need to be set up and have the taper of the nut made concentric to the threads. Another job that is easier said than done.
I did get some er11 collets off ebay that were rated AA quality and said that they were within 0.008mm for tir and they are definitely better than that.
There was another company from Taiwan , making an ER system and the nut has a slot in it for a special spanner that allows the nut to be done up or undone and extract the collet. No spanner flats etc on the nut and no eccentric retention piece as well. The threads were ground and the nut taper ground as well.
They also work very well. Tried finding them to take a photo but are in the moving lost stuff at the moment.
|Thread: A very nice 2.5cc control line speed engine|
Most F2A engines use a Bronze or BeCu for the liners, with 30% Si piston material. Some still use steel balls while most now use ceramic balls in the bearings.
Awesome Barrie. The work that has gone into that engine is nothing short of incredible. Quite a team effort from design concept to the manufacturing. I have seen the amazing gear Rob has and the skills he has to us it as well. The edm of the ports really is something, and will be a big part of the consistency and the performance gains that does not happen with every casting. The precision that is on one of these is hard to explain to people and to why it is needed. I like the way they can calculate quite accurately the thermal changes in a running engine and then the dimensional changes that are occurring. Some parts 5 micron doe snot really matter, other parts a 5 micron error makes it become an also ran engine.
Thanks for the posting and pictures etc.
Great to see.
|Thread: New Lathe - poor suface finish on my results|
A photo of what you are getting is a bigger help. And what tooling you are using as well. Then more accurate advise can be offered. There are some carbide inserts that are very sharp these days. They work well on lower powered home hobby lathes. The very sharp inserts are made for cutting plastics and Aluminium. But do work very well on steels with light cuts. Sometimes you need a small nose radius to reduce deflection and tool cutting pressure.
Sometimes the poor surface finish comes from other factors, like vibration from the motor or belt drive system etc.
So no one answer to the problem. A photo can help to eliminate the various options.
Nothing wrong with hss steel and learning to grind and hone your own tools. Sometimes a shaped piece of hss is the best option , especially for forms or repeating short length tapers etc
|Thread: Drill sharpening?|
We have at work a Darex drill sharpener. It works well, but I still hand grind mine. Yes with deep holes, the more accurate you have the drill sharpened, the straighter the holes turn out. And yes they take less pressure when sharpened correctly. With most drills to 1-1/4 (32mm) I just drill directly. No pilot , just start from a centre drill.
Set up is important as well. Things to check is tailstock alignment when drilling in the lathe.
In my experience the life of the resharpened drill is seriously effected by the surface finish on the grind itself. Rough out using the standard grade wheel of 40 or 60 grit, and then finish with a fine wheel of 120 or finer. An alternate is to hone the edge. These will last every bit as long a s a new drill, and if sharpened correctly will drill a hole to be better than 0.05mm of the drill size and have a roundness of the hole better than 0.03mm tir. Hand sharpened or fixture sharpened should be giving the same results. Hand sharpening drills is a skill that some can never manage. Although it looks ok, when used won't be. You know when it is right as the swarf comes off fairly evenly from each drill flute. I have seen many new drills that require a touch up to get them to drill proper holes.
|Thread: Sodium Nitrite|
Out here I can only get it from an industrial chemical supply place, and have to have a current chemical handlers licence to purchase and use.
|Thread: Surface Plate & Height Gauge recommendations|
Well out of curiosity of looking at the new Kitchen counter top, engineered stone. With the light and reflections looks fairly flat. I set up a dti and a plate with 3 point and moved it around the place. The whole area is better than 0.04mm. The majority of the centre area is well better than 0.02mm. So instead of buying a 1m granit plate for the shop,when she is not home, the kitchen top will work just fine. Thanks for the heads up on that. I have no idea how they even get them that good. Not often I am marking out pieces longer than 300 mm. But when needed have ample space as long as it is not heavy, oily or will not scratch the top. Just have to make sure the height gauge base is clean first.
I bought a few years ago a digital height gauge. One of the cheaper ones. About 1 weekend after using it a lot that weekend, wish that I bought the type with a hand wheel like Mitutoyo make. Did not need to be Mitutoyo but that type. My friend did pick up a brand new Mitutoyo for a rediculously cheap price, because they were no longer going to be stocking that model any more. Ahhhh
Sometimes you can spend more time getting what you want from inferior gear, and the right gear allows you to have Sunday free to enjoy a nice meal and glass of wine.
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