Member postings for Martin Connelly

DC31k, the question is regarding work holding for drilling when you don't have a scroll chuck not drill holding.

Martin C

The very first thing to check before applying power is that the 110/240V switch is set to 240V if that is what you are running on. Otherwise everything looks good to go. You may get away with not connecting the enable wire.

Martin C

Bill, your book extract says use a chuck in the headstock to drill the workpiece. The OP asked what was done before chucks were readily available.

Martin C

It would not surprise me to find that in a busy shop there was a dedicated role of drilling out centres for the turners. You could set up a drill with suitable kit just for this job and pay someone a lower rate than the fully trained turners. Keep the expensive workers doing the thing they are good at rather than the low skilled jobs of selecting and cutting off stock to size and centre drilling the ends close enough to the centre.

Martin C

As long as the added capacitor exceeds the peak applied voltage and can handle the wattage I see no issues. You may need to have a higher wattage for it than the one already in circuit as it may have a higher current flowing through it as it has the current from both legs of the circuit. Additional temperature protection may be needed where the capacitor is mounted.

The two likely failure modes of open circuit or short circuit are no really different to not having it there. When slow speed is selected in one case the fan will stop, in the other it will switch to high speed.

Martin C

My centre height is 4" above the ways which have large flats. A steel rule marked in inches and reasonable light (and reading glasses now) are all I need to set or check things out.

Martin C

I've re-read your post and see what you are planning now. In that case I think you need to be careful using that surface as a reference plane. The level you used on the ground surface can bridge over low spots that a depth mic will not. Not knowing the order the surfaces of the base were originally machined in or how well the casting was aged before machining it puts its quality as a reference surface in doubt. I think you need to check the height of the scraped surface relative to the surface plate it is resting on. Shim it (or use machine jacks) so that three corners are the same height then take your measurements to find how the scrapped surfaces relate to those 3 corners. Put support under the fourth corner as well to avoid droop of any sort in the base casting.

Martin C

I think there is supposed to be clearance between that ground surface and the table above it. So, don't spend any time working to get it flat.

Martin C

I make small knurled aluminium disks to put on the shanks of small taps to use a finger and thumb to turn them. It gives good feel for what is happening and there is very little weight to assist in snapping them. You can see one in this video. I just Loctite them on and have not made a depth stop as shown in the video but they make tapping small holes feel a lot better.

Have a look at this Understanding the threading dial as a guide. You should then be able to work out your own details.

Martin C

If you go for R8 collets then get yourself one that is Ø16 and you can then get an ER16 collet holder with a Ø16 parallel shank for when you need to get in close with cutters or drills up to Ø10. This uses up far less space than a drill chuck and can be fitted into the R8 at different heights to suit the work that is being done.

Martin C

I had some collets made for a CNC pipe bending machine with an internal parallel knurl, like a very fine spine in some respects. It was done on a vertical shaper by the "light machine gallery" as it was called at work. They did all the jobbing work that nobody wanted to put on the expensive CNC machines because of very low numbers or because they were one offs. Sadly it was shut down and such work became sub-contract operations or bought out items as a result. The best option now would probably be wire EDM. Another option for split collets would be to make a very hard knurl that the collets can be squeezed down onto before they are also hardened.

Just as an after thought, the moulds for plastic bottle caps have to have a form like a straight knurl. Find the people who make these moulds and you can get them to do some tooling for you.

Martin C

The process of putting in plastic pipes is basically the iron pipe is either cut or smashed with a hammer and the plastic pipes fed through the old pipe. Holes are dug outside each property to connect them to the new pipe and put plastic pipe through to the meter. This will often require a hole to be dug in the area near the meter as well. For some households the meter will also be moved to the outside for free if it suits the owners needs and wishes (happened to my neighbour). I had plastic pipe already dating back about 20 years due to an extension being built so the old concrete patch was dug out again in the pavement to connect my existing pipe to the new main. The new patch looks a lot better than the old one.

Martin C

There was a video on the news of water pouring out of a gas meter pipe so water got into the gas pipes. The old iron gas pipes are being replaced around the country with plastic pipes because the iron pipes are cast and so very brittle. Water mains are at a higher pressure than gas so if there is a water leak that is either near a broken gas pipe or washes away enough soil to cause a gas pipe to collapse then the water will pour into the gas pipe as its pressure is higher.

Given that this has happened when a lot of places are going to be using gas for heating I can only imagine there is a lot of work to be done to clear out the water from all the appliances that have been flooded with the wrong fluid.

Martin C

I needed a spanner to do up some M2.5 nuts a few weeks ago. I have a suitable box driver but could not use it due to poor access. I cut one out of a piece of old bandsaw blade with a Dremel and stoned the outside edges for comfort. It is not pretty but it works.

Martin C

The other thing about a VFD/3 phase motor is that you can have a slow start-up that will take up any backlash without a massive clunk. Judging by the earlier posts that would be a welcome thing.

Martin C

Blondiehacks has just launched this engine as a project.

Martin C

Based on my communications with Eric, the ProbeIt originator, both my macros and ProbeIt use G31. The operation takes place in the Smooth Stepper I use. The only thing I can imagine is that there is either something in or not in one of the macros that is causing the issue. My macros do a "while ismoving() wend" loop directly after the G31 is called so that nothing else happens until the G31 finishes. Without this it is possible the lookahead is doing something in ProbeIt that delays the response to a G31 move and so causes an over-run.

My probe is a Ø16 piece of ground steel with a thread on the end to suit an ER collet or a Posilock collet. The other end is drilled out Ø10 and a piece of acrylic is fixed in place with anaerobic adhesive. This is then drilled and reamed Ø6 and a Ø6 hardened and ground dowel is pushed in. Nice and cheap and accurate but not immune to over-run damage.

Martin C

In the RAF we were banned from putting NFF (no fault found) and had to put UTRF (unable to reproduce fault) instead. We frequently asked if we could put problems with the seat-stick interface, sadly the answer was always no.

Martin C

Anything from the genuine suppliers will have details such as name, address, account or meter numbers that are not normally available to the scammers. Anything missing such details is best treated as a scam until proven otherwise by means other than clicking on a dodgy link. Almost all the scams I see are vague about who they are for, along the lines of the "dear mum" or "dear dad" I need money ones, that do not say who they are from as they do not include the purported child's name.

Martin C