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Member postings for not done it yet

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Thread: Need a lot of help from you good people
20/08/2019 21:27:56
Posted by Tim Stevens on 20/08/2019 18:01:10:

SoD says (above) - A 15 Ah battery can deliver 15 Amps for an hour.

Sorry, but this is based on a misunderstanding. It is true that a 15 Ah battery willl (should) deliver 1 Amp for 15 hours, but that is not the same thing. 15 Amps would overload a small battery, causing overheating, and likely damage to the plates, if continued more than a few minutes.

It is just one of life's (many) swindles, sorry.

Cheers, Tim

Spot on regarding the hype. They should give a capacity at a particular discharge rate (and probably a final voltage, too).

Usual is C/20 discharge rate. Rate over 20 hours. Faster discharge means rather less capacity. Fully discharging also shortens the life of the battery. Lead acid technology needs careful attention for good battery life.

But, of course, Lithium ion batteries also require careful nursing to get the maximum from them. Battery management systems on electric cars is a must - then they will last years with heavy charge and discharge cycles. Your average cell phone or tablet battery won’t last as long for several reasons. Different chemistry, full charge/discharge cycles, and ‘china’ factors all help to destroy them in a relatively short time.

Thread: LED Dimming
20/08/2019 13:46:46

When it gets to the working end, LEDs are operated with DC - or only on half-wave AC. They each actually require only a small forward voltage of about 0.6 volts before they start to conduct and they can/would thermally run away if the current is not controlled/limited. So I’m unsure as to what this proposed power supply will do for you.

220 volts is well within the voltage range supplied by the grid. Our supply could be as much as 254V, but everything supplied for 220V should be OK as most(?) items bought in the UK will bear this voltage on the rating plate.

Thread: Kennedy Hacksaw bearing replacement
20/08/2019 13:36:28

There is nothing stopping you using a loctite, or similar, product to help secure a small drive pulley. One which does not require too much heat to enable removal?

Tumble dryers and washing machines use very small drive pulleys with fairly extreme wrap around, spring-loaded adjusters and ony 16-20mm polydrive belts as I recall.

Thread: Mill hand wheel upgrade
20/08/2019 11:06:22
Posted by Howard Lewis on 20/08/2019 10:40:35:

Am sure that Arc Euro will help if at all possible. Since you have a Seig machine, it is likely that they can


I doubt it is economic to send hand wheels to the other side of the Earth? China is much closer and better (subsidised?) postal rates!

Thread: Thread sizes on flexispeed meteor lathe
20/08/2019 10:21:36

Whit and UNC are very similar, but not quite universally interchangeable. Whit is a 55 degree thread and UNC is 60 degrees, for instance. Pitches are mostly the same (1/2” are different by one tpi).

A set of thread gauges might be a useful addition to your toolbox.

Thread: Need a lot of help from you good people
20/08/2019 10:12:25

Just took a cursory look at this post. My only comment, before moving on, is that power is only needed to accelerate and replace energy lost by friction. The latter is low (and fairly constant on a level track). Acceleration is a different ball game entirely. F = ma in Physics and needs to be taken into account when sizing motors.

F is Force, m is mass and a is acceleration.

Thread: Profiling tools
20/08/2019 10:00:31
Posted by Robin Graham on 20/08/2019 00:36:57:

I Question is - how big a profiling tool can one run on a 'domestic' lathe? I had a look at JB and they list up to 25mm diameter which would be 75mm (pi=3) cutting engagement if plunged to radius.


How are you calculating that value? Circumference is Pi.D. Cutting a full half circle would be Pi. D/2?

Thread: Mill hand wheel upgrade
20/08/2019 09:32:12

I have two hand wheels to change. A larger diameter one for the table of my mill, to reduce the effort, and the tailstock wheel on my lathe because it does not have a handle. Neither are difficult but it is just getting round to it as both are functioning at present.

Just get one you like, in the correct diameter, but with the correct boss, or one that can be altered. I would not recommend cutting a keyway on the lathe unless you have the correct tool to use with the saddle locked (not seen the doubleboost video - he now sensibly uses broaches?). Drilled, before boring, and cleaned up later is an option.

Do get one with a loose handle - I find fixed ones are not as nice in the long run - however shiny they might be.

I intend making one handle from scratch and modifying the boss of one I already have - when I get round to it! Shaper will be used to cut the keyway as it is built for that type of job.

Thread: Wasp trap - suggestions please
19/08/2019 23:00:39

Wasps at this time of the year will not be aiding the grower, either by pollination or by catching pests for feeding their larvae.. The nest is breaking down; the wasps will eat fruit or other sugary substances.

The new queens will be mated and soon hibernate until next spring (I don’t know when the hibernation period might begin). Presumably the queens will still be feeding up for the winter? Yes, wasps are an important part of the eco-system. They and their nests should not be destroyed earlier in the season, unless a specific nuisance.

One possible reason why Neil may be seeing more insects than usual is the ban on certain non-specific insecticides - those that kill or damage bee colonies (amongst the rest of the insect population that also suffers). Another might be the increased temperatures due to climate change?

We need biodiversity more than some think. Humans try to alter the eco-system (agriculture) to their advantage but in the long run we must learn to live with nature and not try to change it. A bit like climate change due to fossil fuel burning altering the carbon dioxide levels in the atmosphere. A bit like the destruction of the ozone layer by man-made CFCs, which is only slowly recovering after the ban on the worst offending chemicals umpteen years ago. Kill all the insects and we kill ourselves, eventually.

Thread: Kennedy Hacksaw bearing replacement
19/08/2019 17:51:31

Videos of Kennedy hacksaws always seem to be ‘fast and furious’. The Edgar T version (Hemingway kits) run at a more leisurely pace at around half that speed?

240 rpm with 4” stroke equates to only 80fpm cutting speed, but they just seem to be very fast.

Thread: This weeks offer at Lidl
19/08/2019 16:11:37
Posted by Neil Wyatt on 19/08/2019 15:58:04:

You could get a computer UPS to power the heating. Be aware that they are probably the most unreliable bits of kit known to humanity. Alternatively a leisure battery kept topped up and the smallest inverter you can find.

But do make sure, if you do go the leisure battery/inverter way, that you use a pure sine wave inverter - not a cheap square wave option - if there are any electronics involved. For short outages, the car battery might do if the battery was good (without having to run the engine...).

Thread: Wasp trap - suggestions please
19/08/2019 16:01:35
Posted by Plasma on 19/08/2019 15:00:58:

Google waspinator. It's a really effective wasp deterrent rather than trap.

The highly territorial wasps see what looks like an established nest and go elsewhere.

It really works and is eco friendly.


They don’t work, according to all(?) the beekeeping forum threads!

Further, I doubt that wasps are very territorial, now that they are sugar feeding.

19/08/2019 14:58:27

Have a look at the video, on this advert, for a high efficiency wasp trap. It is one advert of many for wasbane type traps. Karol, the inventor of the WaspBane trap, is a well renowned expert on wasp habits.


The fellow on this advert specifically tells you that if you remove the attraction, the wasps will go elsewhere.

I keep bees and would now never consider putting any wasp trap close to my hives - not even if a hive is being troubled by wasps! By all means attract them somewhere else and trap them!

Clive’s trap works because the wasps fly towards the light. A better trap is one with entry slots lower down and no possible exit at the top. Clive’s version is easier to load and empty.

The WaspBane traps are high efficiency. With your jam jars, any wasps which escape will simply return with a load more of their sisters from its nest.

I reiterate - remove the attraction and the wasps will go elsewhere for their sugary sustenance.

19/08/2019 14:20:32

Simple. You don’t need a wasp trap at all. Remove the reason why they are there and they will go elsewhere. Your traps are simply attracting them!

Most wasps will now be hunting for sugar - unlike earlier in the season when they were being fed by their larvae.

Have you checked your eaves, etc for a nest entrance?

Thread: Spotted on facebook market - free
19/08/2019 12:19:32

Already gone!

Thread: Using the faceplate and dog on a Sherline lathe
19/08/2019 12:10:23

This recent thread might help where it def says there is a morse taper in the spindle?


Just cut your own. Run the dog in the chuck jaws, not the face plate. Usually can use a drive plate on most lathes.

Edited to add: just cutting a centre in the chuck could be sufficient (for each separate job) and be driven against a chuck jaw or slot?

Edited By not done it yet on 19/08/2019 12:15:38

Thread: This weeks offer at Lidl
19/08/2019 11:24:24
Posted by SillyOldDuffer on 19/08/2019 09:18:51:
... Older generators are particularly prone to voltage swings because their regulators are slow acting, perhaps even a mechanical cut-out.

Not all of them! You are maybe too young to have experience with older types of generator - the current armature type rather than stator generators with an electronic AVR. smiley

My genny is a large (for domestic use) 4.5kVA Stamford armature generator driven by a Hatz E-75 (which starts black smoking at around the 3.5kW mark). Rotating armature, rather than the field, and the heavy rolled steel frame around the static field windings seems to give it much more back-up ‘grunt’ to get larger motors going and a much cleaner sinusoidal output. It was already ‘quite well-used’ when I purchased it about 40 years ago.

Perhaps not particularly large in output power, but very heavy. Only on Saturday did I start it for the first time this year. But I cannot load it into my little car (I did try). It will remain as back up should the grid go down, even though we have a disproportionate number of local feeders, due to the one particularly heavy leccy user just down the road.

19/08/2019 07:52:19
Posted by Hacksaw on 18/08/2019 20:04:46:

... Do you think i've damaged the variable speed board ? I can't see that I could have burnt out the motor windings...

Many modern electronics are not made with sufficient resilience - to less than perfect sine-wave supply. Particularly items with inverters included (modern welders and plasma cutters). I suspect that electrolytic capacitors won’t cut the mustard when the voltage rise time might be a bit steep or with other transient voltage spikes on the supply.

Even non-polarity conscious capacitors can be junk these days - so many old cars with Kettering ignition systems suffer with failed ‘new’ condensers. I’ve only ever had a couple or three condenser failures on my vehicles/machines and none from the 1930-50 period. I try to fit capacitors with higher voltage spec than the originals, but not always possible...

Thread: TTFN
18/08/2019 12:32:17


I totally agree with the first three replies.

Thread: Digital inclinometers
18/08/2019 08:32:55

If your eye is good enough for non-critical settings, then an instrument should do just as well (or better) for non-critical settings, too! I think you need to distinguish between non-critical and precision. They are not the same.

Only if the angle needs to be a precise value or you are matching an existing part (even then you would check it?) are angles that critical. In those cases the angle must be precise. If making two parts to fit together the angles might need to be precise but still not so critical that the angle must be of a specific value.

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