Here is a list of all the postings William Chitham has made in our forums. Click on a thread name to jump to the thread.
|Thread: mini grinders|
Never used one but a pencil type air powered die grinder might be an option, maybe they don't use so much air as the standard sized ones. Very fast and not too expensive if you already have a compressor. I noticed this one in MSC's last advantage sale:
|Thread: Boxford AUD/BUD single phase conversion|
I've done my CUD with original motor and a Mitsubishi VFD. I was accustomed to the original stop start switch and much prefer it to buttons so I devised a wiring scheme to retain it. I had to dismantle it to rearrange the contacts and some were burned out but there were enough usable to do what I needed. Photo shows my prototype enclosure to be remade in steel when I get round to it, and you can just seen the VFD tucked into the cabinet. I have also attached my schematic wiring diagram. Please note, I am not an electrical engineer, this was devised with help from this forum and from the chap at Inverter Drive Supermarket who is a mine of information, so use at your own risk. It has been working without any problem for a year or so.
Edited By William Chitham on 11/05/2022 12:55:03
Edited By William Chitham on 11/05/2022 13:03:23
|Thread: Step Turning Carburettor Needles - Video|
Sorry if it isn't straightforward to view, I don't think there is anything I can do about that. It's a shame because this guy puts up a lot of fascinating posts about machining small parts using a fabulous collection of machines, especially Schaublin.
Beg your pardon, should work now.
Nice video on Instagram showing step turning small diameter parts,which I believe is a topic that comes up from time to time on the forum: SWISS TOOL MAKER
Edited By William Chitham on 17/03/2022 14:15:02
|Thread: Hammer Handle Supplier??|
Thanks Jason, I've seen the Zoro range but I'm reluctant to buy without seeing the eye dimension. Zoro are particularly hopeless at properly specifying items in my experience. The other link is interesting as they are selling the Richard Carter handles, I have sent an email to them asking for dimensions. This is the only uk supplier I have found so far with the proper info but the the 16" one that would fit is too long for me: FAITHFUL
This one in the states looks just the job, I'm sure I'll find one in the uk eventually: Hammersource
Edited By William Chitham on 09/03/2022 16:39:50
What a hilarious lot you are.
I could make my own but time is short and ready made handles are inexpensive, probably cheaper than the material would cost.
I expect to have to do some fitting but as far as I know you can't "shave up" a handle that is too small.
If I "search correctly" I find many suppliers but very few that specify by eye size as well as length. Length isn't an adequate way to specify a handle. Richard Carter for example only quote length and apparently don't sell to consumers anyway.
Handles are not cylindrical, a 16" hammer handle with 2" sawn off isn't a 14" hammer handle, it is a 16" handle with the end sawn off.
The most important dimensions are of the eye but on consideration I think that I would prefer a handle 12" - 14" long.
Just found Rich Carter but they only specify by length, I've sent an email enquiry. I found a Faithful that is the right eye size but at 16" seems a bit long to me.
I have a 1lb ball pien hammer in need of a new handle. I've found lots of suppliers of wooden handles on line but none yet (outside the US) that specify the size properly by length and eye size. Mine has a 1"x3/4" oval eye, not too bothered about length. Any suggestions for a supplier?
|Thread: Steel Blue recommendations|
Plus one for Phillips Cold Blue. I use a similar process to the Grindstone Cowboy except I give parts a preparatory scrub with detergent and I warm the solution by standing the container in a larger bath of hot water while bluing (bain marie?), and I give the parts a rub over with Mansion House polish which produces a nice finish. Don't know about the rust inhibition but makes them smell nice for a few days. You can see the finish on this parting tool holder:
Not saying a sharper tool won't help but what how did your set up actually change between the straight and tapered cuts? Have you done something to make the set up less rigid? Are you putting the taper on with the compound slide and if so is it now at a drastically different orientation to the work? I'd be looking at things that actually changed before concluding that the constant (ie the cutting tool) is at fault.
|Thread: Myford Steady on a Boxford|
When I bought my Boxford it came with a Myford fixed steady which didn't fit of course. I expected I would be able to sell it and buy a Boxford one with the proceeds but it turned out that Boxford ones are four times the price so that plan was shelved. Instead I decided to make a riser block which I have finally got round to. I found it quite tricky working out the geometry to fit the lathe bed, it took a few goes cutting grooves in a piece of Delrin to dial it in but once that was done it was fairly simple. I made the riser out of block of EN1A from Rapid Metals with piece of hot rolled for the "keeper" plate.
|Thread: Lathe change gears vs gearbox|
My Boxford started as a non gearbox "C" but I have since upgraded it to "A" spec which is a huge improvement - the convenience for threading is nice but the real benefit is being able to play with feed rates easily. If you do go for a Boxford I'd suggest you get one with as many extras as possible - especially steady rests, thread dial, t-slot top slide. Boxford bits seem to cost a fortune, far more than Myford as far as I can see.
|Thread: A nice find|
The micrometers are nice but it is the box that really catches my my eye. I love the catches made from hinges but what are the dovetailed in pieces for?
|Thread: Boxford ?|
That's a Model A, looks nice. There should be a serial number on the right hand end of the bed where the tailstock is sitting in the photo. Have a look at lathes.co.uk for Boxford information, there is also a Boxford group on Facebook with lots of scanned documents and knowledge.
|Thread: Vfd and motor efficiency|
Happy to help Martin, here are a some photos of my motor's innards showing the star connection and the finished job before varnishing. I bought the red varnish expecting something translucent but it was actually opaque, more like paint. If I did it again I'd go for the clear. As Andrew said the connection was soft soldered, it did take quite a bit of scrubbing with fine emery to clean the insulation off the winding ends to get a good joint on to the new tails. There are a couple more photos in my Meddings album.
I've just rewired an old Newman motor as described by Andrew. First one I've done and a bit nerve racking but it went ok. I found the star point was tied in on the same side the existing 3 tails came out, not surprising I suppose but for some reason I'd convinced myself it would be the other side so I ended up undoing all the binding unnecessarily. The windings and insulation are rather brittle once untied but I read somewhere that the existing varnish can be softened with a hot air gun and that worked really well making it possible to squash the revised wiring back into place ready to tie. I failed to find any of the special binding string within my patience span so I used cotton string but I found a supplier called Brocott who have the special varnish in small quantities and various other winding related supplies including the glass fibre sleeving.
|Thread: I need to cut chamfers into x64 pieces of mild steel - any advice?|
I have skipped through this thread rather but if I have the gist of it correct then maybe this machine currently for sale on the Home Workshop **LINK**site might serve:
For Sale: Gravograph bevelling machine
Mon 6th Sep '21
Advert ID: 40428
Tools & Parts (Small tooling)
|Thread: Newman Motor Star To Delta?|
Well here are the windings:
and here are the instructions which emerged when I opened the case - these are the two sides of an oil soaked piece of paper so rather transparent but legible:
I wonder why they would make two versions of the motor, with and without dual voltage. Some small cost saving i suppose.
In a spirit of enquiry I think I will reassemble it and try at as is. If it is too feeble I'm pretty sure I'll be able to dig out the node and rewire it.
The Steinmetz circuit looks interesting but I do want the VFD extras (reversing, speed control, jog) to make power tapping easier.
Normal 3 phase is 400-440v. The "synthetic" 3 phase from a VFD is 230v. Most 3 phase motors can be configured to run on either voltage - star for 400v or delta for 230v ("dual voltage" motors) and this is usually made clear on the spec plate. Motors that are not intended as dual voltage, like this one, may or may not be easily converted depending on whether the node of the star is accessible or not.
However, I had a conversation with the fellow at the Inverter Supermarket who pointed out that it the motor may run satisfactoraly at the lower voltage as is. Here is a link to an explanation of how that works:
Basically the motor can be considered as a 230v 29Hz motor so will run at about 60% of normal RPM. Above 29Hz torque will drop off but that may not matter because one normally uses higher speeds for smaller drillbits which require less torque to turn. Definitely worth trying I think.
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