Member postings for Nick Wheeler

Nigel is confusing tube(sized by OD) with pipe(ID). These are normally used for different purposes, and sized according to the relevant dimension.

So you don't get their drivers writing the card as they walk up the path, stuff it through the letter box and leave without knocking? We'd have the same service if they got the normal postman to deliver the card and not even pretend to deliver parcels.

There's an excellent chance he lives in Medway. Although useless isn't strong enough to describe how bad Royal Mail is here.

John, here's my virtual mock up of a hotrod IRS using MGF hubs, brakes and wheel bearings. The flat components are to be laser cut to save time and effort and make better parts

The rest of the frame, using MGF front uprights and geometry

I do intend to build this at some point. It's a mock-up because various parts need to defined better. And the IRS has several degrees of camber gain, which need to be designed out...

Some more:

Traditional drawing requires you to know where everything is and how they're related. If you don't, you won't be able to design or place new features. CAD is the opposite; it tracks the details, so you can just add to centres of edges or bores, on corners, 'drill' holes through four parts in one operation, view at a different angle, section a part at the click of a button etc. Which in turn enables you to concentrate on your actual design work, that the computer can't do.

There's usually more than one way of modelling parts. Considering how you're going to make the physical object often decides which is the best most efficient to use - the three concentric features of Nigel's cylinder cover strongly suggest a single revolve for the basic solid to me, just like they would for a complex spindle. The notch and hole pattern being so closely related would come from another sketch. This is where you start to get the benefits of 3D CAD, because this thinking is equally applicable to making the actual part.

Not understanding what the program expects from you. Intuitive is a word that gets thrown around a lot, but like common sense, its attributes are a long way from universal. This affects all complex programs, not just CAD, and is something the software industry handles really badly. Impenetrable or contradictory jargon, non-existent or terrible or out-of-date manuals, constant 'upgrades' to the user interface and useless error codes are just the start of a long list.

There are lots of features with specific uses that are really tempting to use willy-nilly - grid snaps, automatic projections, multi-point splines all need considerable care to not leave you wanting to put a hammer through the screen. A lot of my time is spent on car parts, where left and right is taken from the driver's seat not from the front view

These programs are advertised and sold as easy for everyone to use. That should be added to the list of The Great Lies of All Time.

Do you have a grid displayed? If you do, you probably have grid snaps turned on as well. These are a really frustrating trap - turn them both off, and forget they are even possible. Then you can choose a sensible feature(corner, centre of a shaft or bore, etc) to fix to the origin and constrain/dimension from there.

One tip I found saved me a load of grief was to deliberately draw lines, boxes, etc so they obviously don't meet/align, and force them to do so with constraints before going any further.

The same way their predecessors with treadle machines did; by operating within its limitations.

A VFD driving a 1Kw 3 phase motor won't make a good Myford any more accurate, but it will be nicer to use and a bit easier to consistently achieve good results - like tweaking the speed slightly to make the drill cut better.

That cover is two concentric circles, a construction line, a 'solid' line and a point all completely constrained:

That's hardly complicated, is it? The geometry is fixed, so the actual dimensions are largely irrelevant. Although I would have modelled the cover in place at the top of the cylinder, using projected edges and known dimensions which is even easier.

Then it's an extrude for the cover and another for the recess. Use the hole tool centred on the point and a countersunk/counterbored/stepped is easy. Pattern that as required around the part's axis. Use the 'solid' line to cut off the corner. Finish with fillets/chamfers as required. In brass:

Dan, I bought my first lathe and then a mill for similar reasons to you. The second job I did was to make a new handle for the freezer, that I had broken several years earlier.

I understand why you don't want to build a series of little engines etc, but a making couple of them would be good teaching exercises for the processes and techniques that you will use in the future. This way enables you to learn them in your own time, with projects that don't matter, using replaceable materials instead of one offs that are needed now. That's the real reason for many of the frequently touted 'beginner's projects'; a complex centre-height gauge isn't that useful compared to the time it takes to make one, but the various parts teach how to make things that work as expected and how you need to think about appropriate fit&finish.

Fusion works the other way, think join this to that.

Surely the threads are the same, but less important things like the size of the heads/nuts change?

Let 'em.

You don't have to for your own stuff...

I never did the job a cheap bead roller was acquired for, and it was abandoned outside for several years. It resurfaced as part of my recent Grand Clear Up, so I decided it was time to make it usable.

I cleaned the worst of the grot, freed off and lubricated the shafts, and replaced the crappy hardware:

These are cheap for a reason: the slotted 10mm steel plate twists as soon as you apply some tension, and gets even more out of shape as you roll the workpiece through the machine. It needs to be a lot more rigid to do some real work.

Fortunately, The Grand Clear Up also provided some grotty angle iron that had been fence posts for about 50 years, and wasn't usable for anything important. A few minutes cutting and welding, with the ends clamped parallel, sorted the rigidity problem:

I ought to make a stand for it - some scrounged gate post, welded to a wheel is likely - but it does work clamped in the vice. A sliding fence for the workpiece will be easy to make, as are some tipping dies.

And a small 12v winch motor will save the need for another pair of hands to use the thing properly.

That's a much better and more efficient way of learning about your new machine than making decisions based on measurements you don't understand. I've never put a DTI near the spindle of either of the lathes I've owned, although I do spend some time fiddling with the change gears to get them to run quietly...

3D CAD would be a lot less frustrating for new users if it didn't allow you to MOVE, DRAG or ALIGN parts by wiggling them about randomly with the mouse. Then you'd have to learn to constrain/join/mate them properly using the relevant features in the parts. Like using the centre of the flat part of the thumbwheel, joined to the centre of the hole on an outside edge of the clamp - the two surfaces that on actual parts would bear on each other.

And turning off the display grid and its snaps should be the first thing to do before using the program.

As above, you don't need the origin planes or axes to align/join parts. That's done using their own features(circle centres, edges, corners, whatever), with specific ones added just for that purpose if nothing appropriate exists already.

Why limit that to todays kids? I'm 53, and would much prefer to push a button and get a finished, or at least usable part. The machines are only tools, how they work isn't actually important. Unfortunately, standing in front of manual machines twiddling knobs and levers is the only practical way of getting the work done. Bigger machines are the obvious improvement, simply to reduce the amount of time taken.

There is no way I would buy a new lathe, mill, pillar drill or pretty much any machine tool that wasn't variable speed.

Interesting that you bring that up, as his entire statement is about ensuring that what you know is actually right. That's what a good teacher(tutor, mentor, whatever buzzword you prefer) would establish and help you correct. The bit about 'unknown unknowns ...... being the difficult ones' is especially apposite here.

There it is again: your insistence that you know things that aren't true or relevant. You're right, you can't learn this on your own. You need a competent teacher.

For everyone's sanity, take somebody(anybody) up on their offer of some one-to-one tuition as soon as possible. For instance, your issue of how to close a file could have been solved with one sentence and the demonstration of two mouse clicks - that's what, twenty seconds instead of several posts? It's highly likely that the revolve problem could have been solved in a similar fashion.

Wouldn't making them both the same component be likely to increase the spindle vibration? And it would definitely mean an expensive custom motor instead of a simple, standard one.