By continuing to use this site, you agree to our use of cookies. Find out more

Member postings for Andy Stopford

Here is a list of all the postings Andy Stopford has made in our forums. Click on a thread name to jump to the thread.

Thread: Arduino low power alternatives
07/08/2020 20:53:10

Just a couple of points:

You can program a bare bones ATmega using the Arduino IDE just as normal - if you've burnt in the Arduino bootloader it is an arduino, effectively.

But, you won't be able to do it using USB, unless you add a USB-UART chip (and socket) which of course complicates things a bit; if you go down this route it's worth designing a custom PCB and getting it made in China (£10-ish for 5 boards from a company called Elecrow - others available, but I've found Elecrow good).

A simple way to get round this is to use the DIP package with the appropriate socket. You can then swap it for the one in a standard Uno, program it, and return it to your project. It's not ideal, it's fiddly, the pins are easily bent, but OK for something where you've got it working how you want it using a test setup with an arduino, and now you want to complete the 'production' version.

Lastly, do yourself a favour and ditch the Arduino IDE - there are much better, easier to use alternatives, with full code completion, hints, colour coding, etc.

I use PlatformIO; it's available as a code editor plugin. I like the Atom editor, but you can use it with VSCode, and, possibly, others.

06/08/2020 20:29:12

+1 for using a 328 on its own; if you set it to 8 MHz it will be stable at 3.3V with a usefully reduced power consumption. They come in a variety of packages, both DIP (solderable with a standard iron) and SMD.

Depending on how you are using it, you may be able to let it sleep, to be woken up up when required by an interrupt from some other device. Since you mention using it for a clock, then a Real Time Clock chip, e.g. an MCP7940N, could provide the interrupt, as well as providing your clock functions.

Also, you don't actually need the crystal, the ATmega 328 has a built in crystal, which is adequate for timing its own cycle, though not for external tasks, like making a stopwatch.

I would thoroughly recommend this guy's website if you haven't dipped into stand-alone ATmegas:

http://www.gammon.com.au

Thread: Silly issue with HBM parting blade
20/07/2020 20:05:16

These are good, and don't break the bank:

https://www.chronos.ltd.uk/product/new-3-8-sq-shank-clamp-type-parting-tool-with-4-1-2-m-35-hss-chipbreaker-blade/

I think you probably need to get the dedicated holder for them to locate properly. No need to grind the top face of course, which makes life easier.

I recently bought one of these:

https://www.arceurotrade.co.uk/Catalogue/Machines-Accessories/Lathe-Accessories/Tool-Posts/Model-000-Parting-Tool-Holder-Horizontal

If you already have, or are thinking of getting, the appropriate QCTP, then I'd thoroughly recommend getting one to go with it.

Thread: Welding precautions
16/07/2020 20:09:13

I have a Fairway Taxi (the old-school London cab). Some previous owner, possibly the first, had it waxoyled in a totally futile attempt to prevent it rusting to bits.

I keep a small trigger spray full of water to hand during its yearly appointment with the oxy-acetylene torch, to snuff the inevitable waxoyl fires emanating from whatever box section is currently subject of attention (you don't need to be able to see the fire - just misting into the box section through some convenient opening towards the top does the job, a bit like putting out a chimney fire by throwing a cup or two of water on the hot grate).

Re. petrol tanks: in theory the mixture inside the tank is too rich to ignite. Furthermore, petrol is non-conductive (a dielectric I presume?), so I suppose there's no need to insulate the terminals of pumps, etc. - though the submerged pumps that Jaguar used on early Mark 10s were quite carefully earth bonded to the tank if I remember rightly.

Thread: Hylomar universal blue failed to seal oil?
23/06/2020 20:47:43

Slightly OT, but for water-based paint, Albany (Brewers own brand) will give a true gloss (I hate fooling around with horrible, stinky solvent-based* paint and refuse to use it now).

*Yes, I know water-based paint has water as the solvent - or does it? Are these paints solutions or emulsions?

23/06/2020 20:24:07

I don't think Hylomar is intended for metal-to-metal joints, I always assumed it required some kind of gasket and then it would work quite well. It was about the only thing which would make a reasonably oil-tight joint on the card gaskets of the old (pre- 1969-ish) Jaguar polished alloy cam covers. Smearing it on the copper washers for the hold-down nuts of same didn't help a bit though.

For sealing threads like this, I'd use PTFE tape - easy, no need to degrease, and non-seizing when you need to disassemble.

You can get different kinds of PTFE tape - the stuff for gas fitting is thicker, which is handy for larger clearances.

n.b. if you need to seal threads on oxygen fittings, you must use PTFE tape made specially for the job. The ordinary stuff contains a lubricant which might just turn your oxygen bottle into a rocket...

Thread: Hermes Parcels
10/06/2020 19:48:36

My opinion, both from doing the Xmas postie thing, and 20 years' experience in the removal business, is that if you need to write "Fragile" on a box, you haven't packed it properly.

(OK, if I'm doing a packing job, I do write "Fragile" on glassware etc., but mainly because the customer likes to see it)

Thread: DIY drip feed oiler for cutting fluid
06/06/2020 20:23:26

Excellent idea, I'll be making one.

Obrigado da Inglaterra

Andy

Thread: Eclipse 39 assistance please
29/05/2020 21:17:41

Copied from this ad https://www.adverts.ie/machinery-tools/eclipse-no-39-drill-bit-sharpening-jig/2667142

Manual for Eclipse no 39 drill bit sharpening jig

For sharpening twist drills in a range of sizes from 3mm (1/8 inch) to
13 m (1/2 inch)

Assembly
Remove small chrome plated screw from strut. Assemble struct
into body. Fit screw and tighten up.

Instruction for use
1 Hold strut with V channel uppermost.

2 Release back stop and slide to end of strut

3 Loosen drill clamping screw

4 Insert dril into V strut with point away from back stop. Hold drill
in V with thumb. Upturn sharpener to bring drill point into view, align
one cutting edge parallel to and flush with front gauge, which is
adjustable for different drill size.

5 Lightly tighten drill clamping screw

6 Swing aside back stop shim and slide back stop into contact with
the drill shank and tighten

7 Swing shim back into V. This will advance drill the required amount
for sharpening.

8 Check that the drill is still correctly aligned with front gauge and
fully tighten drill clamping screw

9 With one hand hold sharpener between thunmb and finger in side
recesses and with the other hand hold abrasive paper on a smooth flat
surface

10 Roll sharpener up and down the full lenght of the abrasive paper
until cutting ceases

11 Fully release drill clamping screw rotate drill 180 and align second
cutting edge with front gauge

12 Ensure drill shank is in contact with back stop shim and tighen
drill clamp screw.

13 Repeat sharpening action

14 If drill is not completely sharpened, repeat from 6

Note
(a) use whole surface of abrasive paper
(b) do no allow wheels to slide

Thread: Harrison L5A refurbishment
26/05/2020 21:17:26

If you give all the oil nipples on the saddle a shot of oil each time you use it, plenty of oil will work its way onto the gears.

Ditto the gearbox (mine also receives a certain amount of seepage from the headstock).

Thread: Send Them Packing
21/05/2020 20:42:38

I once worked in the warehouse of a small publishing company. The books ordered through Amazon had to be packed with extreme care because if the buyer complained of any damage, Amazon were likely to terminate the publisher's contract. So I wouldn't be surprised if the packers take no chances; their job might be on the line if there's a return.

My favourite over-the-top packers are RS Components who will use something the size of a shoe box to send ten surface mount resistors (which are smaller than a grain of rice, and near-indestructible). They do free next day delivery though, and the boxes can be quite useful, so I'm not complaining

Thread: 3D CAD software - what do you use?
18/05/2020 21:40:44

If you don't mind cloud storage, OnShape is free for non-commercial use, well featured and easy to use.

I'd love to love FreeCAD but it suffers from the all too common problem with open source stuff, that the people who develop it are coders - they like writing code, they probably do it for their day job and are doubtless very good at it, but they aren't interested in user Interface design, user workflow, producing the documentation, etc.

Furthermore, many individuals work on this kind of project, and this can mean that there is no overarching design ethos to the thing, just loads of disparate modules which all do things differently.

This is what you're paying for with commercial software - they have people who specialise in UI, they have technical writers to write the manual and so on. If there's a free version, then that's all the better.

Note - I'm not slagging FreeCAD off, I think it's good, and tremendous that people make the effort to develop it, and if OnShape went payed-for only, I'd probably go back to it. Fusion 360 isn't available for Linux so that would be out of the question, plus its produced by Autodesk, who killed Softimage XSI, the best 3D animation program ever (and a model of good interface/workflow design), so it's it out of the question on principal.

Thread: Cross slide dial calibrations - opinions sought.
17/05/2020 20:47:26

Hi Stuart, yes, I'd definitely be interested to see your code etc., I'm not sure what the arrangements are for sending messages here, maybe one of the mods can advise.

I'd actually be looking first to fit DROs to my mill - I've fitted carriage stops to it, which are useful, but it would be nice to have read-outs.

Thread: Harrison L5 - removing feedshaft, lead screw and associated paraphernalia!
17/05/2020 20:19:36

It's 20 years since I last took my L5 apart so I can't give you exact details, but it's mostly straightforward - I don't recall any need to use a dummy feedshaft.

One gotcha though is that the support at the right hand end of the bed is located by dowels pointing forwards, and the apron is located by dowels pointing upwards, therefore trying to remove one conflicts with the other (You're intended to remove the end nuts and slide the leadscrew and feed shaft out to the right, but you haven't the space to do this).

However (as I remember) if you support the apron and remove the screws securing the end bracket, apron and screw-cutting gearbox, it's possible to wiggle everything free from its dowels - take care, you are depending on springing the leadscrew and feedshaft slightly, but if you're just using finger pressure you're not going to put a permanent bend in them, use no crowbars! It might be a good idea to have assistance to avoid the weight of the apron hanging on the shafts.

The leadscrew isn't fixed to the gearbox, its end just locates in a bronze bush. The feedshaft, I can't remember, I think that might just pull out as well.

I'm (sadly) selling my L5 after we return (more or less) to normality, and to extract it from the friend's workshop where it currently resides will require it to be totally stripped down. Oh joy...

edit: forgot to say, mine (which is the 9" model) doesn't have the 'duff brass screw' but I presume it's something to do with securing the dog clutch to the feedscrew, and if so it shouldn't need to be disturbed.

Edited By Andy Stopford on 17/05/2020 20:26:13

Thread: Cross slide dial calibrations - opinions sought.
15/05/2020 20:26:50

Thanks everyone for your thoughts. I'm going to go for diameter - to me it is more logical, and if I hate it, well, I'll just have to make another dial.

With regard to DRO, it's a very small lathe, and I think attaching things to the saddle/cross slide is potentially adding clutter to get in the way - length-ways along the bed and on the tailstock like Stuart's setup is a very attractive idea, however. I'll keep an eye out for cheap calipers in Lidi and Adl.

14/05/2020 21:09:28

No, it's genuine 1mm pitch metric fortunately

14/05/2020 20:00:07

Thanks Pete. I'm using this method to stamp the numbers:

sam_0349.jpg

It's a bit hard to see in the photo, but the number stamp is laid in the toolholder with the clamping screws just touching it and pushed by finger up against the rear face, then a tap with a hammer and it looks acceptably neat.

OK, I confess the taps with the hammer weren't as hard as they should have been, so after a clean-up skim they're a bit faint, so this one is going on the top slide. Which is good, because it gave me time to think of posting this thread.

And yes, that really is a dodgy amount of jaw to be protruding from the chuck...

14/05/2020 19:24:47

I bought a CJ18A mini-lathe a few months back. It's not at all bad for the price, but there are aspects where there is room for improvement.

One of these is the maddening 0.025 mm divisions on the dials, presumably a 'close enough' approximation for those who would rather work in thousandths of an inch. I prefer to work in metric and being rubbish at mental arithmetic, they do my head in - I have to constantly refer to a cheat sheet or use an increasingly oily calculator to work out what cut to put on.

So, fine, I'll make some new dials with proper 0.02 divisions, but whilst I'm about it, how about doubling them up for the cross slide so that the dial shows the reduction in diameter rather than radius, and save myself even more mental arithmetic.

I know some lathes have this arrangement but I've never used one, and wondered if anyone has any opinions on whether this is a good idea?

Thread: Oil
12/05/2020 20:12:26

I've heard it said that some additive in EP oils attacks bronze components (that said, I've seen synchromesh cones made of something bronzey-looking). This warning might only apply to the notoriously short-lived bronze worm drives which were (long ago) used in some lorries.

EP also smells horrid (ditto ATF).

Thread: Buying a small mill
06/05/2020 20:15:52

I don't think I'd be too surprised if a broken tap shattered when given a bit of crunching from pliers, they are hard, and hence brittle after all, and the breakage might have initiated more cracks than the one that went all the way across.

One tip I'd add re. using taps (and dies), is when you back off to break the swarf and feel the resistance increase, don't carry on backing off; go forward again and then back, and you'll find the swarf build-up will clear without jamming and breaking the tap or tearing the thread.

As for mills - I've got a Sieg SX1L, it's all I have room for and it works well for its size. Using an end mill I find that it sounds happier using a deep cut so that the side of the cutter is shaving the workpiece, rather than the end edges hammering into engagement. I think it could probably handle a more powerful motor - I have vague thoughts of fitting an induction motor and belt drive, though doing this without hanging the motor off the back (and hence undesirably increasing the machine's footprint) looks tricky.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Latest Forum Posts
Support Our Partners
Eccentric July 5 2018
walker midge
Warco
emcomachinetools
cowells
ChesterUK
JD Metals
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest