Member postings for David Davies 8

John

there were two articles in MEW a couple of years ago by Alan Hearsum about making a TTA for his Drummond lathe. This was based on the Myford design.

I have the issue numbers but not to hand at the moment. Will post details tomorrow.

Chris Heapy also described a Myford TTA many years ago.

Cheers

Dave

PS:- issues 233 & 234 Autumn 2015

Edited By David Davies 8 on 29/11/2020 19:57:24

Post script, after consulting the Oracle, AKA Tony Griffiths, the Holbrook must have been a B13 or B17. His description of the cross slide is better than mine!

Dave

I once used a Holbrook lathe which had two cross slides IIRC, one above the other. The top one was connected to a hand wheel on the operator's side and its nut was mounted to the bottom cross slide. The bottom one was capable of being locked to the carriage or connected to the TTA.

l believe South Bend patented a telescopic cross slide screw for their TTA which removed the need to disconnect the cross slide nut. This was only available on their bigger lathes.

One day I'll get around to commissioning the TTA on my Boxford!

Dave

Simon 0362 wrote:-

"Unfortunately I did this before returning the meter to a voltage configuration and promptly put a straight short across 220 V."

This mistake is easily made. For this reason, at work, the leads supplied with (Fluke) multimeters were removed and replaced with leads having fused prods before the instruments were issued to our electricians.

Because of the fused leads an instruction was also made that the electricians should test their meters on a known live circuit at the start of each shift thus proving that the fuses within the prods of the leads were healthy.

Dave

One must also be aware that inverters set to ramp down too quickly (possibly regenerating or using dynamic braking resistors) can cause a chuck to loosen when stopping while running forward.

Dave

The mistake is that the chuck will loosen whilst accelerating in reverse. Applying the brake whilst running in reverse will serve to tighten the chuck to the spindle.

Dave

Peter

as Pete Rimmer says above the conactor is a three phase unit. The live should be connected so that the current passes through all three poles (ie wire all three poles in series) otherwise there will be an imbalance and the overload will trip. The neutral should not be switched but should be permanently connected. These thermal overloads are designed to trip on true three phase overload and also on loss of one phase hence the need to have equal current in all three poles.

HTH

Dave

Derek Hall 1 said

"Well I am thinking to myself to what I would be doing if I was a silly teenager with his mates coming out of the pub/nightclub late at night when every sensible person is asleep in 2031........."look at all them electric cars being charged...lets unplug em all for a laugh"..........."

Didn't anyone hear that alcohol is to be phased out by 2029 for health reasons? Once this is implemented there will no longer be any drink induced tomfoolery.

Dave

I have several Sievert Propane blowlamps, the older handles have a 10 x 1 thread to take the neck tube, the newer ones have a 3/8 BSP RH thread for the neck tube The neck tubes have a hemispherical end which seals against the cone within the handle. No gasket is used. If there is a leak one or both of the mating surfaces is marked or the neck tube captive nut has not been tightened sufficiently.

This method is exactly as used on oxy/fuel gas lamps for the hose tails at the regulator and at the blowpipe.

The burners do have a gasket where they seal against the neck tube but I cannot say what the gasket is made of.

HTH

Dave

Hi Paul

thanks for that, I will trawl through vol 95.

Cheers

Dave

Hi,

in my 1982 version of Ian Bradley's Myford series 7 manual a "shop made" milling attachment is shown in 2 places, fig 10.4 in chapter 10 and again fig 14.3 in chapter 14. Only a short paragraph mentions it in chapter 10.

My query is; does anyone know if this attachment was ever described in the ME or elsewhere?

Thanks

Dave

Ken

setting the topslide ar 14.5 deg is not the same as making the tool match the helix angle of the thread. The leading edge of the tool must have its clearance angle increased as the helix angle increases. If not the tool will foul the work. The trailing edge of the tool does not need the same treatment as the helix is going away from that edge. The treason for the 14.5 degrees is so that the cut is only applied by the leading edge, the trailing edge merely follows.

hth

Dave

You could try cutting an 8 tpi 55 or 60 degree thread first then cleaning it up with the ACME tool.

HTH

Dave

Too quick Jason!

8 tpi ACME thread has a depth of 0.062. if you are cutting this in 0.156 stock that leaves a core of 31 or so thou. Something isn't right?

Zebeddy is a slang term for Unistrut channel nuts...........said Florence. Used by those awful electricians ......said Dougal.

Surely this is an instance of the imperial system being used in decimal mode not in a metric mode?

Thanks for posting this Steve, it is a bit different to the OHC (Pinto) engine assembly line at Dagenham, where I spent eight months in the early eighties fitting Gem 80 PLCs to the four engine assembly lines block, head, whole engine and final dress.

The hot test area had forty beds with slave fuel, ignition and exhaust systems and ran each engine for ten minutes. From memory the output was 850 to 900 engines per shift with the line running five shifts a week.

At the time the last of the Essex V6 engines were being made and as the various processes were completed the machinery was removed. It's successor was the Cologne V6 as used in the Capri 2.8I and others. Also the last mark 5 Cortina was made then with Sierra production starting in the August.

Cheers

Dave

Yes please Neil tho I can,t do Tues.

Sketch of double star connection added to photo album.

Note: Inserting photos is done using the two buttons just before the Smiley Button top right of the editor tool bar.  The 'Camera' inserts photos from a Forum Album, the other allows a URL to a photo anywhere on the internet.   Only JPG images are allowed.

Edited By SillyOldDuffer on 11/10/2020 10:00:09