Here is a list of all the postings fizzy has made in our forums. Click on a thread name to jump to the thread.
|Thread: A (new to me) Tom Senior Major ELT|
Lovely machine....how are you going to move it? looks very heavy!
|Thread: Water in fuel|
Studdied biochem at uni long ago...but....IPA will keep the water in (the fuel) solution and thus minimise corrosive effects. It has bveen used in vehicles up to 40% bv but this can be counter productive to longevity. It is reccommended not to exceed 10% bv in a petrol car. At 10% the RON will roughly increase by 2.5 which is good news for your engine, so its a win win realy. I dont have first hand experience of commercial addatives but its most likely just dressed up IPA...why reinvent the solution?
|Thread: How many Hammers|
got nine...all used regularly depending on job.
|Thread: scratch built beam engine|
Athough not an interferance fit the valve needs to be held close to the port face or air will get under it and it will never seat. Its also possible your timing is out so instead of going to compress the cylinder it is going straight out the exhaust - thick oil is always useful for starting out.
|Thread: Drill running off course|
If I need total accuracy I have found it essential to use a centre drill to start and have the job clamped solid. You need a good centre pop too.
|Thread: Current leakage om CNC|
Ian - it was bought off ebay from China, not a great starting point I know but there are a lot of them used in the UK and apart from me being electrocuted how they make them for the money they charge is anyones guess. Ive now earthed it and it shows varying but very low volts and almost zero amps so its going in the right direction. Nothing tripped and ours is a new house. My mate forced the two pin plug into a uk 3 pin socket - I never even saw it or gave it a thought until you kind lot prompted the questioning so big thanks to one and all.
nope, defo no earth. I will be adding chassis earths and converting to twin and earth 3 pin plug.
Im using the earth of the 240v socket - there is no earth pin of the plug, hence my concern.
Update! I tested the wall socket as advised and all is as should be so I tested the spindle motor - 4 pins, 3 of which were 120v, same as the frame measured. I had a spare motor so swapped it in and ran it up. Now 70v between table and earth. Dissconnect spindle motor and 40v between earth and table. Tested resistance from plug earth to table and no reading at all. I tested wherever I could and got the same no reading. Tested continuity and nothing....now my mate set this up for me so ive never been near the wiring but on investigation I see that the cnc has a TWO pin plug. My question is, woild fitting an earth strap to everything and connecting it into the extension cable (checked that and all good) allow the current to escape or is there a fundemental problem with my machine? Many thanks
|Thread: To Pin or Not To Pin|
Also bear in mind that whilst loctite may state that you have 10 minutes playing time before it cures to such a degree as to make manipulation by hand impossible I have found almost without exception that the true time is just a few seconds (I favout 272 for general fixings as it doesnt run). I would pin the crank.
|Thread: Hints and tips for cutting small(ish) male threads with a die|
I dont do metric but thats pretty much 5ba...I wouldnt wind it by hand, I would use the lathe back gear. If its stripping threads you need to open the split die as far as it will go and try a run. Always use lubricant. The dia of rod is dependant upon your application but it is not unusual to aim for a 3/4 thread engagement. For such small threads it is often much easier to buy threaded bar and locate into a tapped hole with loctite. Good luck.
|Thread: Screaming brass|
Its cz121, it gets used on my boilers for burners and chimney parts and I use a lot of it up to 3" diameter down to 1/4" diameter. It honestly never makes so much as a squeek and I sometimes run it extremely hard in terms of cut depth and feed (you know its OTT when the 3/4" boring bar starts to bend!). What I have learned is to cut it at a relatively low turn speed. Ive got a fixed high speed lathe which refuses to cut brass. I now always use ccmt super sharp inserts, they cut very cleanly. If you are near me I would gladly help you resolve this issue hands on?
Nigel (Pendle Steam Boilers)
|Thread: Aluminium cylinder, Viton rings|
Hi Bob. In a word, no. Definately not a good idea as it oxidises quickly when subject to steam. Your first run will probably be fine but after leaving it standing the bore will oxidise and make subsequent running worse and worse. Personally I would never use O rings as piston rings (I know some do with success) as they have no self lubricating properties, instead I would use graphite yarn for longevity.
|Thread: Screaming brass|
Hi. I turn brass pretty much every day and have never ever had it make any noise - nothing. I can only assume its a special grade or that your tool is rubbing not cutting. I find tips for steel useless as they sheer rather than cut, prefering very sharp inserts instead. Im making a batch of chimney collars today, all brass.
|Thread: bronze or brass|
Im not re-reading it all again but im sure the new regs state that boiler bushes have to be bronze. As for the fittings themselves, to the best of my knowledge all commercially availible are made from brass. At Pendle Steam Boilers we moved to Bronze bushes a few years back much to the frustration of our cnc parts maker who now has to change his tooling more frequently!
|Thread: Battery longevity|
I bought a digital watch 26 years ago to go diving in Turkey when we got married...I swear its still on its original battery and still working - how???
|Thread: Current leakage om CNC|
I am indeed using an extension lead, two infact albeit only 4 ft long each. I will test as advised but go away tomorrow for a week so lack of response on my part will ensue, at least for a week. Lots to ponder and plan whilst away, thanks again.
Indeed the stepper motors are under 40v but the spindle motor is 110v. I have a new, unopened motor somewhere so I will swat it out and retest. Thanks all.
its a chinese set up but the plug has earth. I connected the bed to the trolley, not realy n earth but makes part of the circuit. I dont think there is a workshop wiring fault as it is installed to Iee regs.
If I touch the inside of my wrist against my cnc bed I get a highly unpleasant shock. Ive experienced the same sensation with laptop computers but given that there are just 3 stepper motors and a drive motor I wasnt expecting this to occur. I tested the bed to earth and got 120V @ 5 uamps so virtually no current to speak of. Is there anything I can easily do (other than not touching it) to reduce this? Its all on wheels on a concrete floor. Thanks
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