Member postings for Adrianh

I use a free version of Nanocad for 2D work, you register as a hobby user .

I am closing my engineering workshop so have quantities of steel, cast iron, non ferrous and plastic materials available from post code BA14 6LB (near Bath).

Also small surface tables and various angle plates, benches, vices, drills and a whole lot more equipment from 40 years of engineering, along with Gates lathe etc.

Email me at:- [email protected] if you have any requirements.

Very lucky to do this with this tool!

At this cutting depth you need to provide additional clearance for the swarf, I do this at work on a much larger machine by taking 2 small cuts, 1 approx 2mm offset (for a 3mm too)l away from the chuck to a depth of say 25mm each time. This allows coolant in and the swarf out. At the smaller diameters you need to speed up the chuck to maintain an adequate surface speed at the tip.

When these tools seize they tend to snap the holder below the insert - very expensive!

Also always a good idea to push against the job with a revolving steady to stop it moving out of the chuck.

As stated earlier, the top diameter of a metric thread is actually less than the designated size.

Cutting with a M12 hand die straight onto commercial bar will probably only work if you have a very good/new die and use quality thread cutting oil. It is also difficult to get a straight thread over a length.

Why not start with a piece of studding ( threaded bar) or cut a suitable bolt or capscrew up and tap the end of that

The end of a thread die is tapered to aid cutting and to reduce the stress point caused by a sharp edge at the front end of the cut thread.

Normal engineering practice, if you want a full length thread to a shoulder, is to add an undercut with a radius tool at the end of the thread to a little below the root diameter of the thread.

You get a full length thread and then a radius to the full diameter with a minimal stress raising transition.

To hold a short thread make a flanged threaded bush, with a single split, to fit a 3 jaw chuck or small collet

Have a look at the Transmission Development web site, hardware section.

You could use a double UJ or a nylon sleeve coupling.

Better still would be a timing belt drive as you can have low backlash (Breco or Contiflex).

Prices from Trans Dev are very good. They sell a massive range of drive parts and bearings - mostly Chinese!

19 mm bearings don,t really exist - I guess what you need is 3/4" - this is not a prefered size

If you want a turntable to run true and smooth you cannot use pillow block bearings as they have to much clearance and runout and are not suitable for much side loads.

You need an arrangement with angular contact or taper roller bearings similar to a vehicle wheel unit. To support a table perimeter use small proper ball races ( 2RS sealed type) directly in contact with the rim. You have a choice of very cheap/poor quality chinese bearings or quality bearings for not much more money.

PM me with your details if you want parts/help

I do this every week in my job, you need a vernier, imperial 55 degree and metric/unified 60deg thread gauges and a thread specification chart/booklet.

The diameter of a tap is always slightly less than the nominal thread diameter. Then using a set of thread gauges you can establish the TPI ( teeth per inch) or metric pitch. Take all your measurement furthest from the end of the tap as a first and second tap are tapered.

If you have a lot of old looking taps you will probably find they are BSW or BSF.

Taps marked GAS are ussually BSP parallel.

Remarking taps is almost impossible as the majority are HSS ( high speed steel) with the markings etched on - a Dremmell may work.

If you need anymore I have draws full especially of the older threads

You can purchase very cheap pillow block bearings from Transmission Developments in Poole.

I have a selection of surplus gearboxes and motors if you contact me, as well as a lot of other engineering items and materials, face plates etc - scaling down my day job!.

If anybody has any requirement let me know

If you are near Bath, try Avery Knight and Bowlers near the old Green Park station

I also run an engineering business near Trowbridge and have a lot of surplus material/ equipment that might be of use ( mild steel/better steels/brass/copper/cast iron/pipe and fittings and tooling)

Ring 07860 247582 if you need anything

Adrian

Hello Jim

I have used a similar product to heat my Enginering workshop in the past. They are very quick at heating up a large volume, but very expensive in gas - you need to use large cylinders.

I no longer use them as they are not allowed under my fire insurance terms, I suggest you check the small print of any policy.

I also found that if you do not have a more than adequate fresh air supply you end up with a room full of carbon monoxide, a very dangerous condition!!

You may find it better to use the diesel fueled equivalent - you can use 35sec heating fuel at approx 90 p per litre but you need to be able to store approx 400 litres to be abale to buy at this price.

adrian