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: Could anyone let me know what these are|
If the flat topped tool is a metric or imperial length (measured to a reasonable tolerance) it may be a height setting pillar for items that are quite tall when clamped to the machine bed.
|Thread: VFD Instructions|
Paul, if you have a 1.5kW motor that is not fully loaded it will seem like a small motor to the VFD. It would be a poorly designed VFD that could only be used with fully loaded motor running at max rated power.
|Thread: What is the way to put these holes in the right place?|
Dovetails are measured with cylinders to avoid problems like this. Do you have any silver steel or other ground rod that could be used against the angled face to allow more accurate measurement?
|Thread: Issue 286 Spot drills|
Is the theory of larger angles for spotting drills matched by something similar for centre punches? I have bought centre punches in the past that have been supplied with quite a blunt point ground on them. It may be that they are intended for drill positioning purposes where sharply pointed ones are not or that they are for larger drills with a wider chisel point.
|Thread: Why are washers such a poor fit?|
Should have said .25mm radius, not 2.5mm. I am surprised no-one picked this up!
It is to allow the head to sit properly on the washer when there is a radius between the shank and the head. Eg a 2.5mm radius on a 6mm shank will require a 6.5mm clearance hole in the washer. A bolt/screw without a radius is weaker due to the stress raising effect of a sharp corner.
Edited By Martin Connelly on 24/09/2019 19:07:54
|Thread: Myford super 7 Tailstock Spindle Damage|
I have cleaned one up (not on a Myford) with a reamer. Held it in the 4 jaw to get best possible concentricity of the shank and checked the tip was running true using the centre drilled hole. kept everything locked or pinched to minimise snatching and turned the chuck by hand to take off the minimum necessary to give a good surface. I was only removing raised high spots and leaving the main bulk of the spindle untouched.
|Thread: Aircraft General Discussion|
Have had an F35 passing over recently but today I managed to get a few snaps.
It more or less went around where I was standing the first photo is heading east, then north east, north west then finally west. Lots of noise when it accelerated away.
|Thread: Hi from Mid Lincs|
My wife is from Helpringham.
Mid Lincs must be somewhere near Horncastle looking at Google Maps.
|Thread: Problem with slitting saw arrangement...|
It may help to increase the friction between the saw blade and mandrel by fitting a paper washer before putting the blade on. It will still slip if it jams but may have a little more friction than a metal to metal joint. If you have a second chuck maybe you can hold the mandrel body with it to tighten the drawbar before fitting the blade.
|Thread: Electronic Indexers - How Is Cumulative Error Avoided?|
I made a 127 tooth gear using the calculate each position method as 360 x X/127 and a stepper motor with a close coupled harmonic gearbox. It required 88.8888 steps per degree, just under 252 steps per tooth. I decided that was going to be accurate enough for my needs.
|Thread: What are these change gears for?|
It could also be used as an indexing plate for anyone who wants to cut 127 tooth gears to suit some other gear profile. Advertise it for this use as an option and you may get more interest in it.
|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.
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