Member postings for DiogenesII

Will there be enough tooth engagement to keep the blank reliably synchronised with such a small gear..?

Looks good, nice work!

It's a normal practice in all kinds of assemblies where a lock screw acts on the threads of another screw to provide a brass 'pad' to prevent deformation of the threads - sometimes a neat solution like this, on lesser machines it can be nothing more that a small disc, or slug, of brass.

Likewise a plain rod intended to be locked by a screw will often have a flat machined on it, so that any burrs will not cause it to bind in it's bore; if there is no flat, then a brass pad ought to be fitted.

Aluminium alloys are generally too soft - the pressure of the lockscrew often causes them to expand sideways and jam.

It'd be easily formed on the end of a piece of 3/16" Silver Steel.

The hole is 1/8" (0.125" ) diameter, drilled 1/4" (0.250" ) deep.

The overall length is 17/32" - 0.530" - call it 'a wee bit over 1/2"' - it's not a critical dimension.

The end of the plunger is turned (or can be filed) smooth and has a small chamfer about 1/16" wide all the way around.

Edited By DiogenesII on 15/07/2022 17:32:52

As Baz says there should also be a little plunger about 3/16" round and 1/2" long. It's hollow at the back so that most of the spring fits inside it..

Look in the driptray, on the floor, in the T slots on the cross-slide and especially in the channel between the shears.. ..all kinds of things turn up in there..

Let us know if you find it or not.

Edited By DiogenesII on 15/07/2022 14:39:11

Drilling a straight hole 10 times the diameter (10D) is no mean undertaking, 3D is 'normal' and anything over 5 takes increasingly more care and attention. The simplest solution is to avoid small deep holes at the design stage.

As noted above, for an essential 10D hole I'd use a drill about which I had no doubts, use a short drill to make the pilot as straight as possible, use the correct speed, feed the bit in positively yet without forcing - let the drill cut and use some 'feel'.

I find the most important thing once over about 5D is to withdraw the bit and clear the chips frequently - if you pull the bit out after feeding in 3mm and can see chips are already packed in the flutes, then you will have to do it earlier next time; it's tiresome, but is key.

Different materials and drill bits 'pack' at different rates - if you can see chips 'sticking' there, make more frequent withdrawals.

Yes they are 1/4BSW - GWR Fasteners do 'em.

Howard, do you know if the originals had dog-points?

Do you mean the countershaft pulley or the headstock spindle pulley itself?

Try 'lathe, metal' here;

Vintage Machinery.org - Photoindex by machine type

..always amazed by the sheer quantity of American manufacturers..

Go there with a stick of known height, measure the shadow of the mast, and then measure the shadow of your stick...

Or if it is in the same 'plane of distance' as the fence, say, measure the height on the picture with a ruler, then mark off that same distance horizontally along the fence and go out and measure that..

5/16 - is that depth, width, or typo?

Chronos Chipbreaker blades ?

I like them too.

Edited By DiogenesII on 08/07/2022 15:34:02

AJReeves also supply drawings & castings for a few different R/Toolposts inc. the GHT ones.

Might be worth checking how the centre-height, and dimensions of cross-slide & slots in your (is it a?) Portass compare with those of the Myford / Drummond machines that most of the kits were aimed at - if they are not the same, be prepared to have to 'make it to fit', some castings might be more suitable than others - by the same token, a ready-made RTP for a Myford might not fit your Portass - anyone know?

+1 for gib adjustment - a classic symptom of a 'sticky' cross-slide gib would be "put on a small cut, nothing happens; put on a second small cut, again nothing happens; put on a third small cut, and a huge cut comes off as soon as the tool hits the work" - the total depth is usually more than the sum of what you have dialled in because it often seems to include all & any free play that exists in the assembly, in addition.

If the gib is too tight for the first small movement to have meaningfully advanced the slide, a subsequent movement of similar small magnititude will often fail to find enough 'purchase' in the nut for the screw to hold itself - if the handle is 'going uphill', it can fall back under it's own weight as the screw 'backs-out' a part-turn, giving the impression of excessive backlash.

If you can back off the gib adjustment a bit, it will tell you immediately whether the fault lies there, or elsewhere.

Rowan, the tool in your picture looks like it has a very wide, 'flat' cutting edge - is this for parting off?

Are you using the same, or a different tool, to reduce the diameter?

Yes, what BT said, you should be able to take it all off still attached, hang it up on a bungee or similar - it's not best practise to let it hang from the pipework which can strain pipe / union.

If you do need to remove the actuator first, leave it attached to the hose and it will come out 'dry' and can be moved out of the way. Just refit it, no adjustments or 'special measures' required.

You should check in the 'window' to see whether you will need to DRAIN THE OIL BEFORE REMOVING THE SWITCH - the business end is in the 'wet' side of the gearbox.

Be mindful to ensure the O ring on the new switch seats correctly and doesn't get pinched or twisted on assembly - a smear of oil may help.

Check everything works as expected before taking it out !

Looking very good indeed, Fred..

Could be, depending on where the source material comes from it could contain glass-filled nylon etc..

IIRC even materials like ABS will blunt drill bits on repetition.

Just out of interest what are the dims. of M-Type nose thread & register..?

I wish..

..just thought they'd be the kind of thing that would be a good fit in the OP's stable, are relatively common, still affordable, and do the job..

..was hoping a Senior owner might save me the trouble of hitting the keys whilst I was stuffing my face with bacon and eggs..