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View Full Version : Further Ramblings of a Noob, thoughts and observations



RussZHC
09-03-2011, 11:28 PM
Admiration continues to grow for the group “machinists” as a whole and esp for some who can manage specialties like scraping. Feeling I was born one or two generations too late.

There seem to be a far number of “truths” with perhaps the top of the list being to pay attention to what those with vast amounts of experience have to say...the flip side of that is, and relating to the first note, above, there also seem to be a fair number of “do this when or do this now” situations that are quite counter-intuitive

A “bad” day working at “this” is still better than a “good” day at a lot of other work places...IMO, from someone who could see himself doing “one offs” or small runs for supplemental income BUT not in the pressure situations of large production numbers

What I am doing, getting things to fit together, even when fitting to other pre-existing pieces [not by my hands is the important point there] IS very, very different than what many of you are capable of [homemade tool thread springs to mind, see note # 1 above]. Me = hack, most everyone else that frequents this board, not so much.

Need to go shopping to increase “stock”...I feel guilty when clearly this hobby can be very wasteful, more size variety of bronze for bushings and bearings [must look further at plastics too]

Next lathe be sure to get power feeds, this hand cranking for facing/parting will get old quick IMO.

Last couple of days (my “long weekend”) have been a bit more productive.
Finished the tailstock repair [simplified my “improved” design by dropping the bronze bearings and went back to what the factory did just improved the oiling a bit], appears to work well, weight of a heavy handle is enough to cause it to rotate (to great clearance? but the handle is a previous repair, is oversize and quite heavy). Took three attempts. This means there are now a whole new series of “problems” to be solved.

Ground some “specialty” bits, found a nice mix that covers deburring generally [two ends of same bit, one at an angle to chamfer, one radius to put a “rolled” edge for pieces exposed to fingers/knuckles/hands], another to counter-bore [seems to work well, relatively little chatter w realistic feed, can't go really deep, still], tweaked the roughing tool when it appeared the edge was going away, much better now [added a bit more of a radius to the nose than previous version], realized why one bit did not seem to be doing what it should have been [ground correctly but on the wrong set of planes...bit not square so it was the odd one out of those I've done from that batch of raw bits, lesson = pay attention]

Got a good start on the steady rest (when bought did not have one, seems to be the case with a lot of early Sheldons, guessing it was still on the option lists), two rings with spacers [needed a reason to buy a cheap ring roller] will end up somewhat close to what the factory offered, a bit from late 1930s and a bit from mid-50s.

Tried parting off for first time, went slow, a bit fearful and it was going well, until...guessing the sides of the tool were not ground with a taper going far enough back along the blade...lesson learned: don't assume or trust what someone else (unknown) has done [used a parting blade that came with the lathe...][will ask question in another thread]

Scottike
09-04-2011, 12:57 AM
Russ;
The truths will come with experence; for now just work on the experence part. (just don't break anything) (and really, they're only advice.)
The "counter intuitive" part will go away with time and practice as well, and even become second nature.
We do this because we enjoy it, no other reason is needed, some make a living at, some not, it doesn't matter.
Getting things to fit together is the ultimate idea around here, so feel yourself right at home.
You can never have too much stock, but you can go broke getting everything you think you need. Keep a few of your favorite sizes & materials on hand, and order up the rest as the need arises.
Just stay away from the freebies (junkyard stuff of unknown origin)
Yea, I'm currently rebuilding my QC gearbox so eveything is hand feed while it's off. I'll be glad when it's back in service.
Glad to hear your tailstock ended well, sometimes those engineers actually had a clue. I always give serious thought as to why they did what they did before I make any changes to their design, and usually try to improve rather than redesign.
Don't feel bad about the steadyrest, any reasonable excuse to buy another tool is a good one. My lathe came with one .100 below center and I still haven't been able to use it as a reason to buy something, so kudos to you .
Yea, parting is always scary to me too, but I think it adds to the stress level of the most experienced too.
The thing I've found about parting is that everything needs to perfect for it to work well - blade sharp, properly ground & on center, absolutely perpendicular to the work, and fed at the right speed. Too slow and it chatters, too fast and you break things.

tyrone shewlaces
09-04-2011, 03:48 AM
The thing I've found about parting is that everything needs to perfect for it to work well - blade sharp, properly ground & on center, absolutely perpendicular to the work, and fed at the right speed. Too slow and it chatters, too fast and you break things.

You forgot the most important thing! Cutting oil or coolant. The coolant needs to reach the tip of the cutter where it meets the material so a thin stream works best. A brush will kind of work but not nearly as well as a coolant pump or an oil can.
In my experience, if all the other things are right, too slow a feed hasn't been much of a problem. Even intermittent feeding (kind of a peck cycle) works OK for me if that's what it takes.
RPM, perpendicular alignment of the blade, and application of coolant have been the most important factors when I do parting. The machine, material and the weather may vary your mileage.

Yea, a quality lathe which also has the bells & whistles is more of a pleasure to use. Diligent ear to the ground will get you something nice eventually. It might take a couple years or so but inevitably something will show itself to you. Then again, something might come up next week, so gather up some funds so you're ready to pull the trigger when that day comes.

There's nothing like doing it for a living every day, day in and day out, to gain you some serious chops for machining. But that can also burn you out too - in fact I'd say that some measure of that is inevitable too. In my case, I don't "live" for it like I did when it was all new (long, long ago), but even though I don't get into my own shop nearly as much as I used to I still enjoy hobbying around with it at home. So the trick is to do it enough to gain good skills and not so much you get totally sick of it.

I do remember that getting together with a couple other local hobbyist and even working machinists helped me learn a lot in the early days and it was edutaining to see their shops and equipment and how they did things with it. So I recommend digging up some locals to hang out and talk shop with. Just save the beer and whatever else for after the spindles are done spinning for the day.

DATo
09-04-2011, 11:20 AM
I admire you. You seem to be picking up this craft entirely on your own and that is not easy as you probably already know. You also seem to be making great progress. Though you may think things are moving slowly, clearly, judging from both your join date and the things mentioned in your post, you are doing quite well in advancing your knowledge and skills. Hang in there because like most things it gets easier as you go.

A bit of advice that might be of use to you would be to visit any local machine shops and explain your situation - that you are a hobbyist learning machine shop on your own - and ask if you could buy material from their scrap bin at the same price they would get for taking it to a junk yard. This may get you some material at a good price but more importantly you might just make a connection with whoever you talk to especially if he is the owner of the shop. Long ago when I started my business I went to a company which sold garage doors and accessories like insulation ect. I happened to talk to the owner of the business who was a gruff old guy with what appeared to be an attitude. When I explained that I was starting up a business and had a lot to learn his whole attitude changed. He invited me into his office and spent a lot of time giving me advice about starting up a business. It was obvious that he enjoyed running his company and was eager to pass his experience on to someone who needed it. This taught me a valuable lesson, to connect with people who could provide free advice and take an interest in helping newbies. He wound up giving me the supplies I needed for free and told me to come back from time to time and let him know how things were going.

If you can connect with people like this by moving around and knocking on doors you never know what may happen. You might be able to swing a deal for some work or barter your time for materials or tooling. Just to be around people who do machine shop work is a plus because sooner or later you will benefit from those contacts.

Scottike
09-04-2011, 03:23 PM
You forgot the most important thing! Cutting oil or coolant.

Absolutely Correct!, I did forget. My only excuse is that I was tired, shouldn't have had that last glass of wine, Short term momory loss, Blah, Blah, Blah.
Thanks for catching my oversight.