Member postings for Barry Thurgood

As one who prepared bolt schedules back in the day in construction industry steel fabrication. Bolts have a plain shank for a length as near as you can get to the thickness of the parts being connected unless the parts are very thick in which case 1.0 - 1.5 times bolt diameter into the part on the thread side. If threaded full length they are screws irrespective of diameter. Bolts can act in shear, tension or a combination of shear and tension. Nowadays for most “simple” structural steelwork screws are used. There have been many reports in the journal of The Institution of Structural Engineers on the use of screws and shear “slippage” as the threads crush when the shear load is applied, bear in mind tolerances for bolt/screw holes <=20mm - bolt dia plus 2mm, >20mm bolt dia plus 3mm! Personally, for systems resisting lateral loads such as bracing or sway frames I specified Friction Grip bolts but opens up a whole new can of worms.

Spent 50 years in the Construction Industry (Structural Engineer) and remember as the drawing office junior in 1971 one of my tasks was converting imperial dimension to metric and putting the Letraset “Key” on drawings to show they were metric.
Structural Steelwork is still rolled in imperial sizes merely converted to metric and rounded, ie 203x102 UB right up to 914x305 UB. Similarly masonry is largely imperial converted to metric and rounded, perhaps a little more so as it is hardly a precise material.

Having been taught imperial at school and metric in further education I find switching between the two for larger dimensions easy but must admit to a “feeling” for a couple of thou that I don’t have for 2 decimal places of a millimetre.

Guess I join the Old Gits Club 😜

Hi

A little late for the discussion perhaps, I have used Manifold clamp bars from the Triumph range of car engines, the earlier ones are about 1.75” and the later about 1.125”, you may need to grind off the “pimples”

Thanks guys

much food for thought, I think I will practice centring up on the four jaw, probably quicker than changing chucks and good practice for someone whose last serious workshop experience was nearly 40 years ago!

i have been using Decathlon’s derailleur degreaser (smells nice) and car body shop panel wipe, both of which work well but are a tad more expensive than 89p for 500ml.

Thanks again

Hi All

Not exactly a newbie but more of a returner, approaching retirement after a career in Consulting Engineering I am equipping a workshop to revert to more hands on work. I recently purchased a Chester VB11 lathe and overall am pleased with it. When delivered it was coated with some protective “grease”.

I purchased a degreasing aerosol made by WD40, it degreased quite well but I should have checked on an inconspicuous area first, if left a few minutes to pool it also strips the paint so take care if using !

On a different note the chuck mounting is on a small register and then by bolts through the spindle plate. A bit fiddly, has anyone fitted a “quicker/easier” mount. I was thinking along the lines of the Cone type fitted on the Harrison lathes in the college workshop for the “practical” work back in 1970.