Member postings for ALLAN QURASHI

Howard; Not sure I understand your thinking on tapered (male) into tapered (female) threads being effectively parallel thus no interference. My understanding is that taper to taper is the ideal self sealing situation because it equates to a rotary corking / wedging action along the whole mating area, including thread roots & crests. In fact, I believe the only reason PTFE tape on taper to taper is used is to reduce friction because of the high metal to metal contact area. Whereas taper male into parallel female only wedges at the female entry edge and parallel male into taper female only wedges at the tip.

If you do need to fill taper to parallel thread 'voids', thread sealing cord works well ( Loctite 55 for example).

For the more woke amongst us, please read male & female as external & internal.

Edited By ALLAN QURASHI on 23/07/2023 13:49:06

sorry....180 (ish) apart.

There are indeed two, 90 degrees apart.

Yes thanks again Chris, Russ & Robbo. I recently bought a 60. A lovely machine, so it's nice to find a set of instructions to go with it. Interesting that there's a 2BA threaded hole in the centre on the top of the slide's hex clamp block ( item B), which looks like it's for an oil cup. On the only other example I've seen, there's a threaded hole on each end which secures a pair of button felt oil pads, although they only wipe the clamp block surfaces, not the saw frame. No sign of these on the instructions, but a very worthwhile DIY improvement (or Kennedy upgrade).

The belt tension is a concern...it's so high to stop slip, but that puts an awful lot of load on the 2" long plain bushing, so just wondering has anyone done a 'timing belt' upgrade to a Hexacut? I suppose a poly vee belt would reduce the tension a little, but with so little wrap around contact on the motor pulley, would it make a worthwhile difference?

Hello Edward, welcome to the hobby.

I use a great thread size chart that I'm sure you'll be dead chuffed with. And it's a pdf so you don't need a big wall to pin it to.

Unfortunately the posting page here tells me it doesn't support pasting links in when I try. Worse still it doesn't tell me what it DOES support....and the pasting icons don't do it, so here's a talk through;

Go to haugfasteners.co.uk. Then click on 'bolting guides' then click on the top one ( guide to screw threads). It's a pdf so you can save yourself a copy. And; credit & thanks to Hauge for producing this chart.

Good luck, Allan

Hi Chris,

omeg.co.uk/potentiometers/ are worth a try. You'll be spoilt for choice.

You might have to google it because the forum machine wouldn't let me copy & paste an actual link. Good luck

Edited By ALLAN QURASHI on 14/01/2023 21:47:46

Hi Dave,

What about a tasteful hardwood stand for his mobile phone or laptop? I find things usually take at least twice as long as anticipated, so best not go too ambitious with those available 'boy hours'.

Hi John,

Looking at the first photos you posted (of below the chuck) it appears as if the corrosion was pre-existing before the headstock was installed, because it runs up to the headstock to bed joint with no change of outline or intensity. And there's even a small splash of what looks like touch-up paint on top of the rust. Not good to have corrosion trapped between two precision ground critical faying surfaces.

Customers are the last line of quality control....the inspectors work for the company, not the customer so their POV will be; no news is good news. You're right to report your unhappiness back to them. Good luck, Allan

Interesting to read the preferrence split between one or two chuck keys. FWIW Vic, I found the best thing I ever did was make a spare chuck key. With a really poor short term memory using one key was painfully slow for me. Did I just turn the chuck 90 or 180? Did the workpice need to go toward or from me? Which way did I need the clock to turn? Plus, with one key you can only travel a few thou at a time within the range of snug to tight on the jaws.

With two keys in opposing horizontal jaws, I find it's so easy to traverse the workpiece until the clock zero setting (set 1/2 way between max eccentricity) is achieved, then rotate to the other jaw pair and repeat. One more chuck rotation using one key to tighten only, and that trims out the last 1/2 thou TIR.

pgrbff, I hope this post will display a link to my favourite very comprehensive go-to Thread size chart for you.

According to this chart...7/32" BSW would be 24TPI...emphasis on the S for standard. Paul, that's a great link to the Record Plane details, and they do only say 7/32 x 20 witworth form, i.e. not standard.

I suggest you do oversize, very slightly to 1/4", but being such small increase in diameter, stick with the 20 TPI options so you can 'stay in the groove' as the disk jockeys say. 1/4" UNC should be easy to get a tap and a bolt for.

Good luck, Allan

Glad that works well for you Chris, but seeing you asked, and FWIW;

I only have a little Myford ML10, and only since 2016. For 30 years before that I had a Hobbymat MD65 with 3 studs, so the issue only recently arose for me.

My method is to use a 3/8" OD rod in the tailstock chuck, with a centrally drilled sliding fit 3/4" AF hex MS bar approx 2" long for the 3 jaw chuck, and a similarly prepared 20mm square bar for the 4 jaw. This is primarily for mounting the chucks because the ML10's spindle register is an extremely close fit, and engages before the thread, so if I present the chuck up by hand even slightly cocked, it jams on the register, and the pinpoint loads incurred and the bruising...ughh, makes me wince to even think about it.

For the independant 4 jaw chuck, I just leave the block in the jaws on removal so it's already aligned for next installation, but I've turned the corners off one end of the square block to match the ID of the chuck body, so it can be located centrally and the jaws snugged up when the chuck isn't mounted.

But to the point in question; this tooling also provides spanner flats to untighten an overtorqued chuck, sending the torque back through exactly the same path it was designed to go from the motor to the workpiece, so it can't be wrong. I wouldn't risk using a chuck key to undo a tight chuck, I mean....you'd never consider plugging two 12" long 3/8" drive socket extensions together to use as a 2 foot crowbar!!! And a block of wood between the jaws as a lever; I considered that, but that's a hell of a sideways bending load on the jaws, worsened because they won't be clamped tight like when in operation.

This tooling works well for fitting & removing chucks, and works to remove a high torqued chuck ( perhaps from heavy cuts at large diameter) leaving one's mind free to worry about what's suffering further upstream,such as the woodruff key on the bull gear to spindle, or the little aluminium baulking post stood under the backgear disengagement bolthead, etc.

To cover this I was planning to make a manual turning handle (mainly for short single point threading, and tapping etc), and thought this might be a useful tool to keep the torque of undoing a stuck chuck, wholly within the spindle, but was wondering if a 5/8" diameter expanding bush type arrangement would be able to grip hard enough without slipping. I've never used expanding sleeves so any thoughts anyone?

Sorry Jeremy, In my rush to provide you with pictures, I didn't notice yours is a plain bearing ML10 so probably best to ignore my pictures & instructions above.

But for the suspect setscrew at the bottom of your small pulley groove.....not sure how different your version of the ML10 is, but on mine the pulley cone (and small gear permanently locked to it) turns freely on the spindle whilst the big bull gear is permanently keyed to the spindle. There's a radial sliding toothed peg which locks the two gears together for normal direct drive, and unlocks them for reduction drive through the backgear.

So if you have a similar feature for backgear disengagenment, you could set it to disengage, and that should allow the pulley cone to spin. If it does, you'll know the set screw you drilled to look for isn't there/isn't gripping the pulley cone.

Hi again Jeremy. This is the text from the ML10 instructions version 743K which matches the diagram I posted. Some of the item numbers are different to the 743D version that Michael posted for you. I believe you only have grub screw 54 locking the bull gear to the spindle, and grub screw 144 in the collar that prevents the pulley cone from endfloating, plus of course the spindle gear and bearing preloading collar and their associated lock screws . I'd suggest you do replace the vee belt because they're cheap, reliable and quiet, and that also gives you a chance to inspect the bearings at the same time. Happy overhauling. Allan

I've taken a photo of the spindle assembly drawing, but struggling to recall how to post it on here. Copy & paste doesn't work. Give us a mo. Allan

Hmm, adding pictures was torturous enough, but trying to get rid of a duplicated post is so far impossible. I've tried edit post > click on pictures > scissors > save changes....did nothing. Tried again using the eraser icon, still no luck. I'm even more convinced I should stay well away from going CNC.

So sorry folks; duplicate sets of pics is set to stay.

Forgot to include top face of bed too, plus headstock faying surfaces for absolute cleanliness. And remember to align the pulleys and leadscrew drivetrain....but you probably know that, so I'll leave you in peace. Good luck.

Hi Ethan,

Just eyeballed drawing 11690 that I have for my ML10 and it sounds like you'll need item 43 (clamp) Part number A6491/1 plus item 45 ( adjusting screw ) Part number A6492. The bolt you seem to have been left with is item 44 and is 5/16th BSF x 1.5" long.

Probably best to email Myford, as it may be something they'll have kicking about, but not advertized as so rarely requested.....I guess. But if not, it's simple enough to make....you just have to make sure there's no debris under the front bevel of the bed, which is the clamping reference face. And of course do the checks noted by Howard. I'll try and add a picture of the drawing section.....when I work out how.

Regards, Allan