Member postings for Robin teslar

http://www.ecourses.ou.edu/cgi-bin/eBook.cgi?doc=&topic=me&chap_sec=09.1&page=theory

Eulers formula for basic columns

double the lenght quarter the load

4x4 x 2m 4 tonnes, not in my back room

Robin

Yup, thats what I did. Bit of 4x2 and I drilled a hole in 13mm hole in one end to take a 1/2w bolt/washer nut. the bolt was 6in long and the hole was 3in deep so fine tuning for loading was easy. I only had to support the floor above a bay window, i used 2 and the load was <100kg each

OBTW I nailed the bottom to the floor

No probs

Robin

Well it gets worse, another pal got called up by someone pretending to be a phone security service, telling him that he was ulnerable and someone had atacked his line and he owned shed loads of money. The guy said we are going to cut off your service unless you pay a service fee to stop this of £85. My pal said no and put the phone down and sure enough his line went dead.

10 mis later he got a call back from the same guy saying , there I told you we would cut off your phone. It turns out that the scammer had put his caller on hold (or secret third party conference) which then blocks the line. So scary and he called me on mobile I said wait it will go away

I said get an answering machine

Robin

You are a naughty old boy, enough to make an ME turn on his cross-slide

Cant talk about wimin and boobs, you'll get knurled by the Mod

Robin

hi guys

just cos your paranoid doesnt make you wrong

So hears one for your Xmas stocking, happened to a pal of mine a few days ago. Last week Id been over to clean up his machine from an annoying virus priotector, not a recognised app. It was popping up telling him that his machine had 600+ system error, would he like it fixed. Fortunately he didnt follow it through and calleed me instead and I smelt a rat.

Anyway a few days later he got a phone call from some outfit pretending to be Microsoft telling him that M$ had detected serious errors and he needed to upgrade. Once again he didnt act cos they wanted £87 for the upgrade. Its one of these redirection numbers again

http://www.fraudwatchers.org/forums/showthread.php?t=3882

Wicked

So dont get complacent

If you have ever got to phone a strange number (this one looked like a regular London number) then use a phone box or a payg mobile with almost no credit

Its time BT got its act together, they wont let you block International nuisance calls, I get 6 a day intercepted by my answer phone, one of the best defences

Cheers

Robin

Hi W

you really should have a fuse on the output side - but its your shed

I finally got a surplus psu from a defunct laptop to work, its 19vdc and 3.8A but it wouldnt run the motor directly, so I stuck a 10ohm power resistor which dropped about 4v and it work even with the speed controller. The psu I think kept shutting down and restarting probably cos of current spikes caused by the PWM..

Since then I sourced an industrial psu giving 15vdc and 16 amps for £35 so I think that will do the job and run several small motors. Its a conventional xformer psu with volt control and o/load protection, cost £350 new

Interesting is that dropping 4 volts across 10 ohms mean its only taking 400mA but then I havent got a scope so cant see whats going on

So I think ive got it sorted at last and ive got several of these old cordless things lying around

Cheers

Robin

Agreed SM

Ive had some acceptable Rolson stuff, but this was attrocious.

Yes the Chinese can fake Chinese

Things they do dont bear thinking about, rememer the cell phone batteries that blew up cos they didnt have a charge control chip

Cheers

Robin

RR

What about some scrap scaffold tube, that is 1.5ins NPS, appox 3mm wt

Robin

I bought this on Ebay, new, said it was a Rolson grease gun (£6.50?). I spent all afternoon wrestling with this very nasty piece of kit.

Firstly the grease packing spring was so strong I couldnt manage to screw it together and had to chop a third off to get a reasonable try.

The ratchet was flimsy and unreliable, meaning it would spring open without warning - dangerous

The so -ccalled bleed screw was very bad, no warning that if you continued to screw it in expecting to hit a seat it just carried on through into the cylinder, and allowed grease to spew out, very nasty and fiddly to get it back in to its thread.

Very difficult to bleed, still not right

I shall probably bin it, cant be bothered to raise a complaint and send it back, already wasted so much time on it.

Anyone know a reliable grease gun - I just took these things for granted

A cheap chinese fake

Grrrrrrr

Robin

Hi W

Indeed I have got to find a power supply to replace the battery source. Now I read somewhere that Switched mode supplies dont like pwm speed controllers, probably due to high frequencies interfering . I havent found a discussion on this just now, but some quick test showed me that and 18v smps with a rated output of 7,5a dc wont power this motor. I guess the starting current trips out the overload protection

Do you have any idea what sort of power these little motors draw. As a rule of thumb the current supply needs to be 6 times the fl running current, so it could be a lot of amps 10-20?

Im going to need a serious old fashioned battery charger

Back to Ebay again

Robin

Photo tip FWIW

You need and old white bedsheet, then perhaps a dining chair that you can push the squab out or something to make a box frame. Drape the sheet over to form a white box. Direct some strong lights on the sides, cut a hole in the centre of the top sheet to point the camera down and shoot, do have a plain matt background (green is good)

It the way to take those tasty plates of food pix for example

Robin

Hi Sid

How did you gat the original spring ball oil tips out? Are they screwed in or a push fit. The flip top oilers sound entirely sensible.

Oh BTW, the photo up top shows what looks like grease nipples on the counter shaft. I dont think grease is a suitable lubricant, too high a speed on plain bearings

Cheers

Robin

Hi ME's

I looked on Ebay recently for an auto reverse tapping chuck for use on my Mill (something like an Etco). I was amazed how expensive they were (£250 new), Then I looked at my defunct chinese cordless 18v drill/driver which has failed batteries and too expensive to replace. I bought this out of Aldis a few years ago, cheapo price about 20 quid, so I had my use out of it

It has a 13mm auto chuck and the useful torque limiter. So I took it apart and was amazed to see that it is quite good quality, lovely little double sun and planet gear box, 100w motor. variable speed 0-500. So this will be reassembled with some external wiring t an 18v SM PSU and I shall mount it on a cheap drill stand I had for my power drill. Fix up with a control box for speed and direction.

How neat is that - well I felt a bit chuffed anyway.

and FWIW I'm sure that this system would make a good pwoer drive for my Mill table

Just need to get a toothed belt and some cogs, I think. Ive got an old Bosch lying around also

But as they say, as one door closes another on slams in your face, cos I just bought an actual tapping head for a fiver on Ebay, seems no one had spotted it

WOW

Scary stuff, So who is for Nuclear power?

Robin

Hi Guys

I'm not a welder but knew many coded welders who work on the North Sea. Its an incredible skill, akin to be an artist with a sketch pad. Some can draw , others will never make it.

However, none of us will be welding gas pipelines subject to rigourous Xray inspection and skill testing every 6 months

There are cheap welding Xformers about for £50 but I am told these are rubbish at holding a steady current , so your bead is rubbish too.

When I owned a Kobelco crawler excavator 20 tonner, I invested in a diesel welder made by Yanmar, 200A DC. I remebered from my ech days that when we studied dc generators, welding type were remarkable in sustain a constant current as the volts dropped from 80 oc to full weld. That made welding for rough mechanics fairly easy (even me)

But I guess that technology has moved on considerably so I wondered what you would have in you small workshop. I want to be able to weld bicycle tube for example

Cheers

Robin

Fascinating, thanx W

Robin

Well I wrote a reply here and the site seized up and dumped my msg

After 3 phone calls and lots of wasted time hanging around with moh I fanlly got authorised and can access back number (i think)

I'll never go through this amateurish torture again

BTW I had a similar experience with another publishing house and a mag sub. Must be run by Dinner Ladies. What is it with these people? This is 2012 not 1992

Having ranted MEW does have some well informed articles so I will suck it in and move on

Where's the rant smiley

Hevent turned anything all week

Cheers all

Robin

I subscribed to a year subs, which will start jan 13 but i was also promised access to back issues as soon as i received my sub number, but I cant find how to access the magazine I thought I paid for

what is wrong with your website? Do I have to be a mind reader?

I am so angry

Robin

Yes J 22.2 a typo im afraid 7/8s in

Ady I maybe forgot, this gizmo of mine is only for wood but also useful for 15mm cu tube when plumbing old stuff in awkward places, should work on alu as well

My pal uses his with a diamond disc to cut galv roofing sheet

I also used mine to cut a hole in an old plaster and lath ceiling so as to fit a loft ladder kit. It worked very well but blunted the blade. How else would I have managed.

Oh btw always use googles of course, and a breathing mask for ceiling work or MDF (I alwys do that outside, nasty dust give you emphesema)

Robin

Back to basics and an early belt driven model had power feed and if you ran the travel into a stop, then the drive had a shear pin and you had to go to the foreman for a smack round the ear and a new shear pin. Lovely but seriously cruel old boy who hated stupid boys