Member postings for colin hawes

Brian, my 180 PSI came from the hydraulic pressure often required for the 2x WP on a repaired model boiler The trouble with using one of the bodges is that it precludes a proper soldered repair due to the inability to clean it properly whereas the full size traction engines were riveted.

At 180 PSI ?.....Colin

The railways have a live rail with a warning notice on a fence for those who can read . Colin

I like to use both methods but on intricate things e.g. a gearbox I find that the great advantage is taking measurements with CAD to various parts without having to spend time on lots of calculations to the order of accuracy necessary for the job. I, too, am well into retirement. Colin

Wheel of fortune ? Colin

I have made odd taps in the past from silver steel. To avoid having to relieve the threads I kept the cutting edges very short. Worked O K for one offs on mild steel. Colin

Stellite will drill any hardened steel including HSS it needs to be used at high speed. As it runs red hot it may leave the sides of the hole in a carbon steel soft enough to follow up with HSS, I've never tried that though .Colin

About 1/2 " either side of the weld should do. Temper to blue two or three times. Colin

To be on the safe side you need to temper a welded blade at the weld as it may be brittle there. Colin

I have two imperial machines which have 1/2" slots, a shaper and a horizontal mill. Colin

There's a couple of things to be aware of using a micrometer: the job needs to be very clean and the surface finish needs to be good enough to accept the accuracy required. Vernier callipers are inherently inaccurate for bore measurement as they have flats on the measuring face. Colin

The survey will only accept one choice for me..I use self grind HSS most of the time and CARBIDE INSERT for toughened steel or cast iron.

My mini mill spindle occasionally creeps so I stop it with the red emergency stop button to change tools. Colin

Edited By colin hawes on 01/02/2018 18:45:51

I have a Hilka 6" bench grinder. It has a 1/2 HP motor and is just the job for regular workshop use. The tool rests could be improved but I don't usually use them at all anyway. Colin

I generally use a very light smear of any available grease. Colin

Hello David and welcome,

I find these early workshops fascinating Colin

I have a vice which is similar to the Starrett one which was made for use on a surface grinder and is very accurately ground all over. Colin

I have several side and face milling cutters with missing teeth and experience shows that they work perfectly well on thick material but you need to take more cars if the material is thin because one of the teeth will be taking twice the cut on auto feed. Colin

The problem of long machined strips warping occurred on almost every job I had to do on press tool stripper plates. When the clamping was released after machining the bar could be guaranteed to bend so I always had to use a fly press to straighten them after machining. This is a tricky operation too although this item doesn't usually have to be machined on the reverse side. Colin

I machined EN32 for many years using HSS tools and never had any problems. Is it anything to do with imported steel? I wonder. Colin