Here is a list of all the postings John Baron has made in our forums. Click on a thread name to jump to the thread.
|Thread: Bent woodworking lathe spindle|
I'm sure "Machine Mart" would happily supply a new spindle !
|Thread: fly cutter wear|
this picture is intended to show a fly cut surface with a HSS cutter at 250 rpm and 0.5 mm DOC on EN1.
The actual work piece is a part for my grinding spindle support assembly.
The pin standing next to the block will be a split collet that fits into the hole and clamps against a 20 mm post.
Hi Clive, Guys,
I did try with a carbide insert but I found that they chipped very easily, usually when they hit the edge of the work. probably not suitable for too large a DOC.
Square HSS was the best to use and much easier to clamp. I think that getting the tool radius right and a shallow back rake, about 5 degrees giving more support to the cutting edge is about right.
I designed and made my own fly cutters, because I found that that style of fly cutter was not very rigid and tended to flex. This is what I came up with,
20 mm diameter shaft with a 75 mm steel disc and a piece of 1/4" square HSS. The cutter is double ended so you can have to cutting profiles, one on each end. I can take a 1 mm DOC in steel with this. I run this between 250 and 500 rpm depending upon depth of cut and how good a finish I want.
|Thread: Why are BA taps so blooming expensive??|
Avon tap & die are good too
|Thread: Problems reading from a 3.5" floppy disc|
3.5" floppy disc's die of old age, particularly if they have been allowed to get damp at some point !
What happens is the adhesive holding the magnetic media to the hub looses its stickeyness and the hub can no longer drive the media.
I've just scrapped 2500 of them for similar reasons. If you hold the media it should not allow you to rotate the hub.
|Thread: A new [to me ] style of scam eMail|
Open it in a text editor then you can see what's in it.
|Thread: Trembling laptop|
Replace the charger unit and test again !
|Thread: Pratt Burnerd chuck|
I'd forgotten that I had put pictures of my soft jaws and the modifications that I did to make them far more useful.
The commercial soft jaws that I bought from Cromwell are the ones behind the new aluminium ones screwed on to the front of them
The beauty of doing this is that I can just throw them away and screw another set on the front. A very big advantage is no run out ! You put a piece of round bar in the chuck behind to clamp onto and machine the jaws to suit whatever you want to hold in them. You can see in these pictures a step in the original soft jaws where they were machined for a particular job.
Why not buy a set of soft jaws for your chuck ! Cromwells sell them I paid £20 for mine. Much cheaper than PB want for a set and far more versatile.
|Thread: Short drill or Spot / Centre drill first|
Since I made a four facet drill grinder and started regrinding my drills with it, there is no way that I would go back to using conically ground ones. Apart from being self centring the force required is much reduced which is an advantage with thin small diameter drills.
One point I've not seen mentioned is a drill ground off centre will drill an oversize hole and is more likely to wander.
|Thread: I'm thinking of selling up, whats it worth?|
Hi Russ, Guys,
I bought a Myford badged Denford mill 20 odd years ago and because of a move had to virtually give it away. I got less than a tenth of what I payed for it. Less than two years old as well. I've regretted it ever since.
|Thread: ML7 refurbishment|
I would be concerned about the backplate only screwing partially on the spindle !
|Thread: Ac motor 3 wire|
I use a similar motor on my four facet drill grinder. I used a switch so that I can run the motor in either direction depending upon which side of the grinding wheel I'm using.
There is a picture of mine on the "Gadget Builder" web site, near the bottom of the page.
|Thread: Milling Machine Table Repairs|
I've used locktite epoxy putty for similar jobs. Once set hard it just files down. Once set it is very hard to see it, the colour is so close to cast iron.
|Thread: Spark plug lead|
You could use an "R" clip to fit the plug soldered to the ignition wire.
As far as changing the wire, it would depend upon how it is secured at the coil end. Some are soldered in others have a threaded screw that the cable screws on to. Some I've seen are actually a carbonised cotton thread with a wire pushed in to make a connection.
|Thread: Ac motor 3 wire|
Definitely a two pole 2850 rpm motor ! I don't know of a tumble dryer that uses a four pole motor to provide direct drum drive. Look at the size of the belt pulley and compare its size to that of a 26" diameter drum. The belt runs around the outside of the drum from that small pulley. Also its only a 1/2 Hp motor.
I actually use a similar motor on my four facet drill grinder.
Thanks for the picture ! Yes its a start cap, and yes the motor will run either way.
Your earlier picture made it difficult to see that there were only two connections.
Effectively the black wire is mains neutral. The live goes to one side or the other of the capacitor depending upon which way you want it to spin.
If you do a resistance check between the black and yellow wires it should be the same resistance black to either yellow wire.
The motor will run at 2850 rpm. But without the information on the capacitor its difficult to say whether it is simply an interference suppressor or a start capacitor. The way that its wired it could be either.
|Thread: Removing nylon plug from carbon fibre tube|
"V" blocks can be worth their weight in... well you know what I mean.
The technique that I would have used is some long bolts into "T" nuts on the crosslide packed up the "V" block till I got the height I wanted and then a flat bar on top to clamp the whole lot down. Probably another flat bar behind to stop things twisting under cutting pressure. Then either mill two slots and do as you have done cut the scrap off with a saw, or used a fly cutter to take the waste off.
But that is all academic now. Looking forward to seeing your pictures.
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