Here is a list of all the postings Martin Cargill has made in our forums. Click on a thread name to jump to the thread.
|Thread: Can this converter run this motor?|
The fact that it refers to a "minimum SINGLE motor" probably means that you could run your motor alongside another motor to get around the problem. Try giving Transwave a call, from memory they are quite helpful people.
|Thread: Boremaster Tiplap Grinder|
Thanks to Andydextrous for taking the time to provide a copy of the manual.
Thanks to Andydextrous for the offer of a copy of the manual. I've had the machine for more than a year now and have made a few modifications to it to make it more use as a drill/cutter grinder rather than a dresser for lathe tools.
I made a new mount to make the motor spindle take a cup grinding wheel rather than the original diamond dressing wheel ( the diamond wheel was intended for dressing lathe tools and took too long to take a chip out of a damaged drill or cutter). I mounted the wheel guard further forwards to make it cover the deeper wheel.
To cope with the length of drills I moved the motor back (by approx 150mm) by adding a piece of 120 x 10mm plate between the mount and the motor.
To hold drills and cutters I bought an MT3 sleeve with a parallel outer and then bored a length of 50mm square bar and a length of 50mm hex bar to suit the sleeve. The square and hex have a big washer on one end to provide a register on the side of the tiplap "table" and a grub screw to hold the sleeve in the correct orientation for grinding (to suit the tang of the drill being ground).
I can now use an MT3 chuck, or an MT3 collet chuck to hold ordinary drills and cutters or taper shank drills can be held directly or via reducing sleeves
The orientation of the drill/cutter can be set using the grub screw and then turning the square or hex bar each cutting face can be ground in turn.
I thought that I would have to make a clamp system to hold the parts being ground but I soon found that I could simply hold the square/hex in place by hand as the cutter is being ground.
I hope this helps anyone trying to modify/use one of these machines for cutters/drills. I'll take some photos if anyone needs or wants them.
|Thread: Choosing a mini mill|
Nick. Where are you located? I have a Clarke CMD3000 that I am thinking of selling. I'm located in southern Scotland.
|Thread: Using a vfd for two machines|
All very good but have you considered how you will control the machines? The existing switchgear cant be utilised easily as it will have to interface with the VFD and it won't be swappable between the two machines.
I have a VFD in my workshop that can power various machines. However to do this I have the motors disconnected from the original control gear and each one is fitted with a cable fitted with a 3 phase plug. I then have a control pod with start, stop, emergency stop, speed control and reversing switch that has to be taken to each machine (when it's in use) and this has its own cable.
Its quite messy with having two cables to the machine in use. In addition you have to work out a safe method for holding the control pod so that it's accessible when the machine is in use (and you have to remember that the existing controls don't work!!!! unless you have removed them)
You have to watch to make sure that nobody ever plugs in your 3 phase socket into normal 3 phase mains as your motor will be wired for 240 volts 3 phase and not 415 volts 3 phase, and of course there will be no switchgear feeding the motor.......
|Thread: Motor reverse switch 3 phase|
Good to see that this has been cleared up
Just a word of warning regarding Alain Foote's solution. Connecting a switch in the way that has been suggested will certainly work BUT this leaves the motor connected to one live phase even with the switch on the off position. Thus its possible to receive an electric shock from the motor terminals even when its not running (assuming that the contactor is still energised)
I once realised that some 3 phase DeWalt saws are connected in a similar manner. Their motor control switchgear only controls two of the three phases. The third phase is connected to the motor all of the time, so if the saw is connected to the mains the motor is live.......
Can you give us a picture of the truth table? It may be possible to use the switch to drop out the contactor (I assume your using a contactor/overload in the circuit) as this will prevent you from making a forward / reverse selection while the machine is running. Motors and mechanical bits tend not to like being changed from one to the other while running.
|Thread: Myford super 7 lathe tripping consumer rcd|
Its worth remembering that the RCD is probably looking for 30ma of earth fault current, but this can be a cumulative 30ma. As an experiment try switching off all of the other breakers in the distribution board and then try the lathe. If it trips the RCD then the lathe is probably faulty. If it runs then add the circuit breakers back in one at a time until it trips. This may show that something else is causing the problem. The usual culprits are heating elements (kettles, electric cookers, water heaters etc).
To add to the complication it may be a neutral to earth fault that is causing the problem so you may have to disconnect ie unplug or switch off items to find the source of the earth fault.
|Thread: Buying a new lathe and milling machine.|
If you go for one with nylon gears its worth buying a spare set to sit on your parts shelf, they don't cost a lot and there is nothing worse than waiting for a new set to arrive when you want to get on with a project.
|Thread: Boxford Backplate Problem|
Have a look on ebay. I picked up a new tap for £13. Item number 224216785833 might be suitable.
|Thread: DRO errors, or are they??|
Chuck up a piece of bar (say25mm) take a small cut and measure the result. Set the DRO to zero and then take a second (small) cut. Measure again and compare the measured size to the DRO size. carry on in this manner (without resetting the zero on the DRO) See how the sizes compare. This will show if the DRO has a problem and eliminates any leadscrew or backlash issues. Remember to lock the cross slide each cut. Watch to see if the DRO changes size before/during/after each cut as this indicates a locking problem.
|Thread: .DXF Files for Meccano Chain Wheels|
What about using Mammod style spring drive belts? or if smaller ones are required the springs from the back of shaft oil seals.
On the same subject. My bench vice at work has become magnetised, Its a full sized 6" vice, any ideas how to demagnetise it?
|Thread: Digital readings|
My Tuppence worth (or should that be 1p worth?)
1) About 15 years ago I was calculating the size of radiators that I required for the house I was renovating. I was using an on line calculator that required room and window sizes in metres. I despatched my son to measure the rooms (he was around 15 at the time), He came back with measurements in inches. Playing devils advocate I explained to him that I needed measurements in metres. He went away and disappeared for about 15 minutes, coming back with his mother. The two of them then proceeded to tell me that it wasn't possible to measure the window in metres, because it measured less than one metre.....
After a lot of explaining I realised that neither of them understood the relationship between millimetres, centimetres and metres, nor did either of them realise that 0.7 meters was a valid measurement. It was further complicated that my sons school taught centimetres and these were not marked on the tape.
2) About 10 years ago I was Installing a German machine. At the commissioning stage I had a German engineer working with me, he asked for the loan of my tape measure. After two minutes of trying to measure a size he handed my tape back and went off and got his own. I asked him what was wrong and he explained that because our tape measures have imperial on one side and metric on the other they are very difficult to use, because no matter how you try 50% of the time the measurement you want is on the wrong side of the tape. Don't believe me? get hold of a metric only tape they are so much clearer and easier to use (provided your working in millimetres).
3) Regarding the centimetres and millimetres problem, around 40 years ago my mother worked as a secretary for a Swedish steel fabrication company. At the gates of the factory there were two large ship sized anchors. They were there as a reminder for the workforce to always check the measurements on drawings. Turns out the drawings for the anchors were in millimetres and they had been manufactured in centimetres.
|Thread: In flight social distancing|
I'm just back from Turkey (currently self isolating) The Jet2 flight on the way out was full with not a spare seat on the plane........
|Thread: Moving a Myford VMC advice needed thanks!|
If your anywhere near Fife I have an engine crane and lifting gear. I also have a lathe if you want to make a new handle.
|Thread: Enlarging Holes in Thin Aluminium|
I have a set of step drills that came from Aldi, I bought them thinking that they would be "disposable" but to my surprise they have lasted well, considering that I use them in the course of my employment. I wouldn't hesitate to recommend them to anyone.
I also used to use a tinmans reamer when I worked with a mate repairing Land-Rovers. It was a great tool for making bolt holes line up in bodywork. To make life easier on the hands we used to use it mounted in an old style joiners brace.
|Thread: Vacuum Pump Advice Please!|
It looks like a dry pump, As Ian Parkin mentioned the oil pumps tend to have steel vanes. The vanes you have should be free to move in their slots. The Felt pad etc is probably a filter to remove worn vane debris from being blown out by the pump. The slotted screw is probably a vacuum valve (the reverse of a pressure valve) to stop it drawing too much vacuum .
|Thread: Brierley ZB21|
I found one of these at work a week ago. It was lurking under a storage shelf in our store and has probably been under there for 20+ years. We pulled it out today and started to clean it up. To assist us with putting it back to use can anyone help with a copy of the manual for the machine?
|Thread: Excellent Service|
We used to install Altendorf saws. Each one used to arrive with a bottle of Schnapps packed inside the saw. Beats Haribo. The trick was trying to find out if the customer knew about it, if they didn't it quietly made it's way into the back of the van.
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