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Feels so much more robust too.

@@occasionalmachinist I believe you. Great. That’s how I like things too

Not certain yet, but I'm hoping that may even include finishing this off. (Several other things waiting to be finished)

Only complicated because there is (literally) a twist to the part. If I'd used material say 35 or 40 thick it could have been cut on a bandsaw and just neatened up. Some of the effort is me being miserly and wanting to save material.

Itprobably will be but the alternative is creating unnecessary e-waste...

It's practice...

Provided it does not break, I don't mind either way, but from experience I know that once it does break, repairs never last as long as you would expect - better making new.

Thanks. Not sure when I'll next be doing a drill press belt guard though... (One was enough!)

As long as your feed is steady (and not too fast), it works

Good point

That reactivity is the reason that some form of lubricant is needed. Without a barrier, that raw metal will try to bond to other metals, usually well enough to gum things up.

@@occasionalmachinist exactly this, especially with 6061 and the likes. You may have better luck with some free cutting alloys, but a bit of oil even something like mineral oil helps.

@@ryebis Yes.

Start slow - feed by hand but try to make it slow and steady

@occasionalmachinist Hey. Ir worked fin, I managed to part of brass with success but steel is harder. I think I have to take my top slide and compound apart to attend some looseness. I appreciate your effort making that film. Looking forward to the next one. Cheers mate.

@@JB-ol4vz Well done and thanks for the feedback

It was also a draft title for this video...

No probs.

I'm not sure that on a mini-lathe a rear toolpost gains significant rigidity. The size of them almost guarantees movement somewhere in their construction. There's still the narrow dovetails, the width of the carriage along the ways, the...

Brass is very forgiving. One other tip: make sure the parting blade is sharp. If using HSS give it a touch on the grinder and a stone often to keep it sharpened

Have a paintbrush like the one you've probably seen me use ready. Brass sprays fine swarf around. I use the paint brush to deflect them away from me.

Hopefully of use to people

It's an occasionally used but useful bit of kit. From memory, I last used it to tap some holes on a conical surface. So nice...

Thanks for those thoughts. I've run into the shielding gas flow one before, and with most of these, once you have the issue (and solve it) you can spot it quickly the next time. I must admit to being a bit lazy when it comes to removing prior contamination. The main reason I included that sequence was in case anyone viewing has had similar welds and could not work it out - I'm learning as I go and hope it helps others.

I find the clearance table at the local lighting shop a good place to start (outdoor lights are especially good)

I'll see what I can come up with, but part close to the chuck, make sure that the cutting edge is bang on centre and that there is as little slack in gibs etc as you can get.

All of what @occasionalmachinist said above AND make sure your tool is aligned square to the Chuck.

@@colincreedtattoomachines Yes. I started listing things to do out and that is on there too.

Thanks for taking your time to answer my rookie question. I'll try the tips y gave me.

@@JB-ol4vz I know people who have been home machining for years and they have problems, so you are not alone and it's not just a rookie problem. Thanks for the inspiration though - I have started planning out a video showing some of this stuff.

I once had a guy go off his tree at that assertion - I think he'd bought one and believed that he had bought the best lathe in the world. I've heard stories about sand in cast cavities, oil passages being blocked, bad bearings, mis-alignment and the list goes on. Far better to do a clean up before getting frustrated.

@@occasionalmachinist 👍🏻

Thanks. Lots left out but I hope there was enough to make the clip useful.

Thanks Dave. I had a look at parliament hinges but I'm after effectively 360 degrees rotation so need either 2 axis of hinging (like bar door hinging) or some schmick hinges that won't sag when set up like I have them. There is a plan in motion for doing that at the moment... As for calculating a polar moment of inertia, my head explodes just thinking about it. I know theoretically it can be done, but I have that many tubes running everywhere that even working out the location of the axis of rotation would be a challenge - because of the shape of the truss I suspect that it moves the further you get from the hinge. I might have to measure carefully and see if I can get it up on a CAD system to calculate that and go from there.

Interesting idea - I was considering a gantry type mount, but it would need to have a 6m span in one direction, so getting pretty big. This was a compromise - I think it will work well enough with a bit more work. The Al was chosen for weight primarily, so yes, not the best for dampening.

@@occasionalmachinist I have to say I enjoy watching people learn by doing. Just the honest process of trying something and seeing if it’s better or worse than before.

@@GTRgeoff Thanks. It's an experiment - how well is yet to be determined.

There probably is - if I were better at maths I'd be able to tell you what it is. In my case, frequency is a convenient way of showing increased stiffness.

Not exactly, because as you add stiffness you add mass, which is a natural dampener. Ran up against this little beauty in second year mech eng undergrad. A life of weapons and motorsport engineering has given me a healthy respect for resonance. The function is based on the square root of the spring constant(k) divided by mass(m). f=(1/2*pi)*sqrt(k/m)

@@GTRgeoff Thanks. I had a sneaky suspicion that there was a square root involved, but it has been many years since I've even thought about this stuff.

I'm just going off the numbers I could read on the display. The before read around 100Hz on the display. It's a bit tricky because the Al is reflective too and confuses things. I guess too I should be halving the frequency I'm reading as once cycle should involve an up and a down - that would take it to 50Hz. The main use of the tacho was to get a relative indication of the stiffness of the structure, which it seemed to do.

@@occasionalmachinist "that would take it to 50Hz, so close to 1 cycle per second." One of us has had a brain fart.

"that would take it to 50RPM, so close to 1 cycle per second" Fixed it?

He has a hobby channel mate. Easy to mistake cycles per minute and Hz or cycles per second if it’s not your regular reference measure, and the premise was correctly applied as a simple reference tool of improvement in the desired direction. Maybe you should hop over to breaking taps channel and correct him. 😂

@@stustoys Yes. A Brain fade on my part, but as @GTRgeoff has pointed out, it was intended as a relative measure to determine improvement rather than an absolute number. In part I chose using a tacho like that just to show a simple way to assess relative improvement.

I was just thinking of mass damper, too. It probably won't take much weight. Even a few ounces should do the trick.

A mass damper is something that I have considered. I wanted to get the basic structure stiffened up first; next on the list is the hinge. As fxm5715 says, it would not need to be much. I don't particularly want to guy the first section and statically it is not twisting as much now. My next step is a new design of hinge. The design on there hinges as I want it too but is too loose and sloppy (modified commercial hinges - not surprising in hindsight). If I can firm that up I may get rid of some of the bounce/ flex. Gyros are way too sophisticated for me. I've seen some of the gyroscopic camera mounts and they are rather spiffy. Some cameras now have an anti movement mode on them - if the bounce persists maybe that is the next step.

@@occasionalmachinist 👍🏻

Think of it this way - normally when dividing, the pointer indexes around a set number of divisions on the (fixed) dividing plate. With differential indexing, the dividing plate is not fixed but geared to the spindle, so as you index around, the dividing plate moves just a little bit more. In comparison to normal dividing, the pointer (that moves the spindle via it's handle) has moved in absolute terms slightly more. From memory, I think the standard set of gears that comes with a dividing head can all be made on a semi-universal head so you are safe!

@@occasionalmachinist thanks for taking the time to reply,, cheers

I've used it once or twice since making them. Comes in handy.

I must admit I like cutting gears - there is something I find very soothing about it.

Most people don't need differential indexing - I'm doing it for a set that I want to make. The other use is to produce a 127t gear for metric conversions. Other than that, it's pretty esoteric.

Sorry. I tried to explain it as best I could. Think of it as normal indexing but instead of going a fixed number of divisions, you go a number plus 'a bit'. That bit is dictated by the gearing that feeding back.

@@occasionalmachinist after rewatching it twice! I think I get it. Basically if you want to do more than 50 holes or a prime number of holes, then as long as you have the relevant charts and gears you can do it on the say 50 hole plate and the head will compensate?

@@paulrayner4514 More or less! Which division plates you use and the gearing that works requires calculation (but in the tables/ chart). For the 77 tooth gear I was using a plate increment (10 on a 20 hole ring) that would have given me 80 divisions - but because of that gearing, it dropped back to 77.

Traditional texts on cutting gears with a dividing head say to go around once with a light cut to check the divisions - bit like that first skim pass when cutting a thread. Trouble is, that takes time, especially for a larger gear. Centre punching or using a pen or something would take time too. If you think 15 seconds per mark, that's still around 15 to 20 minutes for a gear this size. I haven't got the patience.

I would not recommend it, as the steel wool would likely scratch up the finish. One thing to try is some aluminium foil. Rub that on the surface rust and you may find it removes it. I don't know why - I have wondered whether rubbing the foil strips the oxide layer off and then the raw aluminium in turn strips the oxygen from the rust. However it does work, it seeks to work- you might have to live with a very slight stain - but it's patina right?

@@occasionalmachinist Thank you so much for your thorough answer!

Yes, although I'm lucky as the draw bar is at my eye level, and that's with the mill being on a platform that brings it up around 200mm

@@occasionalmachinist I mostly commented as the pneumatic cylinder for drawbar action and tool change is 99% for machines which do not use the quill function anymore and have disabled it (otherwise the quill will be pushed down when activating the pneumatic cylinder). Using an impact driver that sits above the drawbar and can be lowered and spun either right or left is the solution for manual mills while keeping the quill functionality.

@@joansparky4439 I've seen it done, and for some people it is a great improvement. I think there are even kits available these days. I was told by a toolmaker once that milling with the quill extended causes more wear (better to use it just for drilling), so even those machines with a quill could productively change over.

​@@occasionalmachinist if the quill isn't available for extending while drilling it would need to be done with the head / table .. (I wouldn't mill anything serious with quill extended farther than 1/2 of the large tool taper diameter). The pneumatic systems rely on belleville washers and the quill being locked + wont work on mills with MT taper. So impact driver it is ;-)

I've always been of the understanding that if a tool points say to the right and cuts in that direction, it's a right hand tool. Looking at the tool itself it is a right hand. Looking at it mounted in the lathe, it could be considered left hand. A bit ambiguous...

@@occasionalmachinist I guess we both been in the trade long enough so I can only suggest you do your own research.

You could use Delrin. That was laminated from several pieces of plywood as it was what I had. The wood can be repaired easily if damaged and as you point out the friction between Delrin and metal may be less, but probably not enough to matter much.

No probs.

One of my early efforts, but with some stuff worth seeing again