Here is a list of all the postings Martin Connelly has made in our forums. Click on a thread name to jump to the thread.
|Thread: Harrison wiring|
A couple of things need to be known to help with answers.
Are there any covers or safety screens with switches that need to be in the safe position to enable operation?
Was it supplied by 3 phase mains at 415 line volts or a VFD at 240 line volts and what are you supplying to it?
|Thread: HSS or CS taps and dies|
I always use Rocol RTD, metric size minus pitch for drilling and anyrhing over 1.5 x diameter for thread depth is a waste of time.
|Thread: Work Holding For CNC Milling|
|Thread: Removing a sight glass|
Hoses Direct sell these as push in polyamide items for tanks with wall thickness of 5mm minimum. Diameter 24mm or 30mm. Really cheap so I don't imagine the Chinese lathe manufacturers would use anything different. Try tapping out from inside the gearbox with a suitable sized socket as a drift.
|Thread: Standard dead length Crawford collets|
I have obviously forgotten about it, I'll put it down to age and time passing.
I think I gave a copy to Tony at lathes.co.uk Thought it would go well with his archives. That may be how you got a copy. I downloaded it and printed it off years ago but have not found it online since then.
Sorry about the scribbling on some pages. I didn't know at the time that it was going to be a useful historic document.
|Thread: Stainless Steel Metric Fasteners|
I have bought them for work in the past from RS or Buck and Hickman. Not necessarily the cheapest but RS always delivered next working day so suited urgent requirements.
Typical method for CNC is to set up a dial indicator. Move towards the indicator until it moves a suitable amount to be sure it is off its stop and set it to read zero. This is the zero position. Reverse away from the indicator and back to zero to check zero is correctly set on the indicator, repeat as necessary.
Move forward another mm or other suitable distance to ensure the indicator moves away from zero then back to the zero position. The difference on the indicator from zero is the backlash value. If you can't enter this value into your program then calculate the number of steps to move this distance and add them to the reverse move.
Repeat the above with the backlash compensation and check the indicator returns to zero when the reverse move is made.
It is probably a good idea to reverse the direction and check backlash from the other way as well.
|Thread: Gyroscope origins|
|Thread: Telescopic bore gauges|
I agree with the two earlier posts regarding dial bore gauges. Yes they are fiddly to set up and to some extent use, it is also possible to misread them. They do however give repeatable results that do not rely on good feel. Cheap telescoping gauges can feel like they need stripping and polishing inside to improve them.
If you need to bore pockets for bearings the dial type may be a good choice for you. As also stated above it depends on a lot of factors to make the decision of what is best for your current needs. When a lot of similar sized holes are required a three point micrometer bore gauge with checking and setting ring may be useful but this tends to be for industrial quantities.
|Thread: Smart and brown lathe|
Join the two previous posts and you've got a model m that belonged to the Atomic Energy Authority.
Edited By Martin Connelly on 15/04/2019 18:43:15
|Thread: Removing a grub screw|
If it is in a through hole then a right hand drill may catch and drive it out of the hub.
|Thread: A close shave or why safety glasses are a must|
Two incidents come to mind from work. I was about to drill a small hole in a stainless nut for locking wire. I asked a nearby workmate to put his glasses on but he was reluctant so I insisted and wouldn't start until he did. Once started (using a high revving pneumatic drill) at some point the small drill disintegrated and a piece hit the workmate just below his glasses on his cheek. He thanked me for insisting on tbe glasses.
Another workmate was releasing a luggage elastic from something and it slipped from his hand. Tbe end swung around the structure it was on and hit the centre of one lens of his safety glasses with enough force to knock them back and cut his eyebrow area. Blinking would not have helped there.
|Thread: Further Adventures with the Sieg KX3 & KX1|
A simple but effective way to set z height is with a ground dowel, 10mm for example. You manually lower the tool to about 9mm above the surface you want to be z=0. You then creep up the z axis until the dowel just fits under the tool and set z=10 (or whatever your dowel is). A bit more time consuming than a tool setting switch but if you have plenty of time but money is tight it is an option.
|Thread: What Did You Do Today 2019|
Helped my wife's uncle sell his lathe today.
Edited By Martin Connelly on 08/04/2019 20:42:58
|Thread: Slot Drills|
Broaching cutters can cope with half a hole as described as the centre slug effectively pilots the cutter. Too expensive for a one off job though.
|Thread: No 20 machine oil|
And this is the lathe.
The mill is in the vehicle pulling the trailer.
|Thread: Please help machining|
You can cut the grooves with a suitable radius ball nose cutter and the work piece supported along its length. Turning the part through 120 degrees can be done in numerous ways. You probably need a hardenable steel but that is also not a problem.
Looks straightforward. If someone said impossible it must have been followed by a modifying comment such as "for no cost" or "at a price you will pay" . Were these professional machine shops?
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