Here is a list of all the postings Toby has made in our forums. Click on a thread name to jump to the thread.
|Thread: Motor speed control on AC motor?|
as long as the supplying socket polarity is ok.
I always run mine via an isolating transformer but that is more so I can safety connect up test equipment to the device under test.
cheaper than you think: **LINK**
Not my choice for motor control though.
|Thread: what is this metal?|
First, no the FIL was not in the nuclear business. He was a toolmaker.
I do know someone who is and I asked him if he could take it into work and get it checked. The answer was not printable
It doesn't oxidise, the scraping in that picture was done before christmas. It is also fairly soft - when scraped with a knife it feels as soft as copper although I haven't tried properly cutting it. I am pretty sure the colour is the base metal, not any form of plating.
It also looks like it has been cut from a longer rod, both ends sawn and the dark covering in the pictures is I think just general dirt from sitting in a box of rubbish for quite a few years.
So far I am liking Rod's suggestion. I gather copper tungsten is used for welding electrodes so that would fit with where the FIL worked.
Shame, I was trying to convince myself it was 18ct Gold although I knew that was a bit unlikely
Recently I was clearing out a the garage of my father in law. Amongst the junk I came across a small bar of metal that felt a lot heavier than I would expect for the size.
On closer inspection it scrapes back to a light copper colour but appears to be denser than copper.
Dimensions are 6.4mm diameter and 48.25mm long. Weight is 22g on my kitchen scales. I calculate that as 14g/cm3.
So unless I have got me sums wrong it is denser than lead (11g/cm3) but the only stuff denser than lead that I can think of that is coppery coloured is gold but that is much denser at 19g/cm3.
Has anyone got any bright ideas or ways I could better identify it?
Edited By Toby on 26/01/2018 09:49:26
Edited By Toby on 26/01/2018 09:49:43
|Thread: Tool Holders for Dickson Clone|
A heads up for anyone tempted to buy dickson toolholders cheap on ebay from india.
I just bought a couple for my boxford from "globaltools2016" because UK suppliers appeared to be out of stock. They don't have a chance of fitting without significant modification.
My post is an original Boxford badged one and (from the look of them) I have a mix of original holders plus later clones which all fit fine so I am pretty sure it isn't the post. However the globaltools2016 ones need a significant amount removing from the Vs to fit.
I also agree with the comments about the difficulty of making them accurately, having milled the Vs deeper I am going to have to resort to hand finishing to get them to fit without rocking.
|Thread: Aircraft recognition problem|
well, in 2010 you could have bought a part share of one at White Waltham, so they do exist in the UK.
I would not have described it has having parallel trailing and leading edges though.
high or low wing? and what do you mean by wingtip bulges?
A Druine Turbulent is small and has parallel leading and trailing edges on the wing and tail.
|Thread: Dremel 3000 slow speed problems from new|
Quite likely but I don't think mine did. I can't remember the details but I do know what when I took it apart the whole thing looked so cheaply made (and didn't run well from new anyway) that I wasn't much interested in fixing it.
I am hoping the more expensive dremels are still of decent quality but I am afraid the 3000 spoiled the brand for me.
my experience as well
mine was replaced (when it stopped working) with a Proxxon which is in a decent league. Quiet, smooth and (so far) reliable......
|Thread: Armoured cable - what size would you reccomend|
Sorry, but the regs do not state that
The armour *can* be used for bonding but only if it is sized correctly for the bonding, again, it is down to the individual circuit design. It certainly does not have to be used for bonding but as a minimum it should be properly terminated and earthed at the supply end as for any exposed conductive part. Of course the first job is to determine whether bonding is needed or not
duct or conduit
To be clear we you should not put T&E (or any other "mains" cable) in the same conduit as signal cables like ethernet etc. If you want both you need two conduits.
Yes, you can use T&E but...........
1) T&E is strictly speaking only approved for "dry or damp" conditions, not submersion in water. If there is any chance your duct could fill up with water then using T&E is suspect. That said, I have never seen T&E degrade due to sitting in water.
2) The ducting really should ideally be good enough to provide mechanical protection, so a typical 20mm plastic conduit isn't really up to the job. Plus it will be a bit small to pull any reasonably sized cable through.
3) Taking 2 into account SWA is almost certainly cheaper than T&E plus decent ducting.
That said, ducting is a good idea if you ever think you might need to replace the cable. Just make sure it is large enough as there is nothing worse than trying to pull a stiff cable through ducting that is too small for it!
|Thread: Motor modification for VFD|
fwiw, the motor on my Meddings drill is 0.75HP and is rated at 1.7A FLA for 440V star and 3A FLA for 240V delta. Running it as delta from an inverter (with about 240V out) and the inverter (a yaskawa) reads 1.7A no load and around 1.8A when drilling a 1" hole through steel. So it never gets anywhere near its 3A FLA.
So yes, 5A means there is something wrong.......
(btw the inverter I use is a Yaskawa J1000 (0.75kw/0.4kW)
Edited By Toby on 21/03/2017 13:30:34
|Thread: Armoured cable - what size would you reccomend|
imho the best advice so far, especially the bit about needing specific knowledge of the existing installation. You are only guessing if you don't know what the existing earthing arrangements are and have measured the Ze and Ipf.
Also excellent advice, although I did just this about 5 years ago and still have an empty pipe running under my lawn. I really must get around to using it....... ;(
|Thread: Milling - What am I doing wrong|
If the diagram is the top view of the piece surly the one that is tapering up is the one that is NOT climb milling (ie the "bottom" one?
Stephen: surely if the workpiece was bowing that much you would see it? There looks to be a few mm taper on the cut but the bottom of the workpiece is still flat on the table?
Just curious btw, I don't even own a mill!
quill or z-axis not locked well enough?
|Thread: Anybody know what these are ?|
That is interesting. I always though that if you tightened a bolt to yield you needed to replace it if it was ever undone. It sounds like you are saying this is not always the case?
|Thread: Voltage drop|
and if you want to know the ratings of different cables a quick google search found this:
The voltage drop in those tables is per Amps per meter but that is basically the same as Ohms per meter if you want to use ohms law and relate it to Clive and Muzzer's posts.
|Thread: Replacing Flourescent Tubes with LED tubes|
I don't know about all but at least some work on DC.
eg this one: **LINK**
specifies 10 to 30V dc
I reckon most here will have tubes that are over 10 years old but we think they are "fairly new".
In reality they will have degraded and not be giving out anywhere near the light they used to. Coupled with dirty covers, no reflectors and gray ceilings (and, dare I say it, failing eyesight....) we decide they are no good.
In 10 years time we will all be complaining that these "new" LED lights are not all they were cracked up to be when fitted and be looking for something that is better.
Don't get me wrong, if fitting new lights I would seriously consider LED but if it is just improving an old setup then perhaps a good clean, a new tube at about £2 and a fresh coat of paint on the ceiling might just do it?
Which reminds me, my workshop lighting is very dingy, perhaps I need to put my money where my mouth is
Edited By Toby on 22/02/2017 18:07:48
excellent advice and I agree, things like whether the fittings have reflectors make a big difference to fluorescent (hence me suggesting painting the ceiling white.......).
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