Member postings for Nick Wheeler

Degreasing and surface preparation are not the same thing!

You abrade the surface so the paint will stick to it mechanically/chemically.

You clean the surface of anything that will prevent the paint from sticking to it. This is the last thing you do before opening the paint, and it needs to be done with something that won't leave a residue that's incompatible with the paint. That's why petrol isn't a good cleaner for this purpose.

Thinners. He'll already have some to use with the primer

Fixed that for you

And mine, although this thread reads as if many of the posters have been imbibing fermented custard...

That sounds just like the ones I saw in Lidl this afternoon. £50 spent would see him making his first cuts a few minutes after getting it home...

Creating internal cavities is no different to external features; draw a 2D profile on a plane or face inside the part but extrude/revolve/etc it so it cuts the material away. There doesn't need to be 'access' from the outside. If you want the new feature to be centred inside the part, create a plane mid-way between the relevant faces. You don't measure or decide where in space it is, the computer can do that far better than you. That plane could even be used to divide the part into halves when the design is complete.

Once again, it is dodgy thinking that is causing all your problems and a mentor physically looking over your shoulder would nudge you onto the right track,

It's also the bit that experience of traditional drafting ought to help with. Weirdly it's the people who don't have that practice that get on better.

Have you actually measured how bad (or not) your 3 jaw chuck is? While you're at it, determine whether it needs to be any better for the work you do. There's no point stressing about micron accuracy if your parts would work if measured with a caliper.

Adding another joint in your part holding is hardly likely to make for better/easier setups....

Edited By Nick Wheeler on 07/08/2023 22:02:08

I just use a digital height gauge set to the measurements I took from the cross-slide and bed ways when I got the lathe. Those are on a sticker near the headstock.

It's not worth spending any more time than that on something I might use once a year.

You are emphasising details like most of the dimensions too early in the design process. You'll start with a few basic dimensions - in this case the gears - and the need for other pieces, then build the rest around them just like you will when you've made the physical parts. It makes sense to me to define those dimensions as editable parameters from the start, which also aids in thinking about the design. A back of an envelope sketch is often good enough for this, which is no different to how you would have done the job with 2D drawings on paper. That sketch can also be done in CAD...

As Neal said, you don't need to determine dimensions of many of the other parts, but just define where and how they fit. That's because the dimensions, drawings, or most of the other processes are just steps along the way to having an actual part that does what you want - you don't get in your car and obsess about whether the piston diameters match the designer's original drawings do you?

I don't design assemblies as separate parts brought into a final file, but keep them all together. That's partly because the free version of Fusion only allows for 10 editable files at a time and you can't edit external files in place. It's also so much easier to see how your crankshaft fits into the crankcase and aligns with the bores as an example.

This LINK is a good example of what we're talking about. And while I agree that the wet timing belt is a terrible idea(ours was done last year at over £1500), the Audi Vee timing chains are a different nightmare especially when you see how the Japanese do them.

Your 'practical' way of building it is exactly how you would design it in CAD - assemble the parts so they work, and build brackets/case around them using the relevant features(axes, mounting faces, bearing diameters etc) of the parts themselves.

Altering the length of the shaft would have been easier using a command to 'extend it to this feature' instead of you calculating how much it needed to be changed. Then when you need to move stuff around again, it will remain the required length.

I agree that a quick paper sketch before you started is a good idea, but it's to clarify your thoughts for the assembly - the wotsit must go here, but it turns the thingy so the side-fumbling dinglearm self reciprocates, so where can the output shaft end up? - NOT design the dimensions.

You could drastically reduce the amount of times you need to move it by using more modern paint; if you use ordinary 2k paint from an automotive supplier, you won't need the undercoat, acid, neutralising or rubbing down. Just degrease, pressure wash, dry in the sun and two coats of paint brushed on about 30minutes apart. Leave it a couple of hours to dry in the sun before reassembling the machine. Polish the column first, and mask the bottom before painting the base.

Dave, the further into an engine you get, the less likely it is to find unusual fasteners. I wouldn't consider 12point male heads to be unusual for things like conrod bolts.

The worse offenders for this German, as they seem to have a competition for who can use the most different fasteners, seemingly scattered around at random.

I'd be more concerned about the M7 nut on the other end. Although both look like candidates for loctite.

I'm with Andy, in that I consider the QCTP to be the best value I've spent on tooling for both the lathe and mill combined. If I ever get a bigger machine, it will be getting one as part of the installation. Mine is Dickson clone, but I'd replace it with a wedge type, mainly because there are a number of special tools I think would benefit from being an integral part of the holder and dovetails are far simpler to cut.

I have a very similar WM250.

Much of my work is done with carbide insert tooling with 8mm shanks, but I've a couple with 6mm. There's no appreciable difference in performance. Bigger shanks would only get in the way, even if they could be mounted low enough to cut properly. The cost difference is against them too.

I've had the Machine Mart supplied version for some time. It's handy enough that I wouldn't consider making a cart now.

The casters are not very good; expect to replace them soon with better ones

I think what Andrew using a donor chuck is not just the best solution, but the only one worth even considering.

It's never going to ring again(although I doubt a thin cast iron bell ever did more than clonk), so epoxy the broken bit back.