DIY lathe design question

[MozamPete]

AIUI, Myford's ML7 lathes used an offset design for decades:

Myford Lathes

Disclaimer: no personal experience, just happened to be reading about Myford's products the other day.

Craig

The offset is so small I have to admit I had never noticed it - I would of sworn the ML7 spindle was in the middle of the ways. But yes, it is offset slightly towards the rear way.

 

[Tozguy]

It seems reasonable to understand something before deciding not to invent a new one.

Especially since many have gone before us and there is not much new under the sun.
However I am all for trying to invent/improve something just for the exercise and the learning it brings.
When I look at your lathe made out of wood I see the hours of fun and satisfaction you got from making it.
Will be watching this thread too, uncovering the 'why' behind how our tools are designed is fascinating.

 

[C-Bag]

While I like my wood lathe, I didn’t really want this thread to be represented by 2x4 construction! This is closer to what I’m envisioning for these purposes...

Much nicer aesthetically than the one in the vid with the aggregate showing. To me the vid one screamed the cement was too dry. Personally I will never tackle a major repair on my lathe without either a spare lathe OR access to another lathe again. There are things like the spindle that you can only make with a lathe. And not having enough ID through the spindle is a PIA.

Everybody has their own focus that differs. Like there are a lot of guys here who have basement shops and the idea of a huge chunk of cement that doesn't come a part that literally weighs a ton is not appealing. I personally after living with with a nomad for 30yrs in which we moved 23 times makes me phobic heavy bulky stuff. I'm not living with that anymore but it hangs in the back of my mind and makes my back ache just thinking about it.

I personally would have something of a hybrid with the metal headstock separate possibly like Rivett design with the bearings able to pressed into the headstock. AFAIK flanged bearings are not really precision either. This way you could have the mass in the bed and ability to take it apart not to mention ease of alignment and adjustment.

 

[Stefants]

I would like to find a chunk of cast iron to use as a reference comparison as I investigate the properties of various concrete compositions. The easiest thing I have come up with so far would be to cannibalize a cooking vessel. I am not sure that cast iron is representative of machine tool cast iron, though, and it’s not my preferred dimension to work with. I see that I can buy a disk of continuous cast gray iron on eBay (and then pay pretty much the same cost over again to ship it). That would work and is my leading candidate at the moment (but again, I’m not sure that’s the best analog for machine tool cast iron). Any suggestions as to where I might find a piece of scrapped cast-iron suitable to my purpose? I am looking for something that could yield a rectangular slug about 5 inches long, 2 inches wide, and a half inch thick. Thanks for lookin’

 

[MontanaLon]

weight lifting plate. See them pretty frequently on craigslist.

 

[C-Bag]

weight lifting plate. See them pretty frequently on craigslist.

Those plates are not like the cast iron in American machines. It can be hard and almost impossible to machine. I bought a big chunk of that durabar iron off eBay and it's wonderful to machine. It is the most like the part of my cast iron machines that I've machined.

But I learned the hard way there can be impurities in the Chinese castings and I don't know what they are but HSS edge in my shaper bit was just sheared off by these two spots. I've been working on truing up the flute grinding jig for my Deckel style grinder which was basically a 3"x2.5"x3.5" piece of Chinese cast with a 1.180" hole through it for the arbor and a dovetail on the bottom. The top, and sides were no problem and the shaper did a beautiful job as usual. I was doing all this because the machining of the whole thing was a mess. The hole for the arbor had .011 play which made it close to impossible the grind the flutes. After closer inspection I also found the dovetails had almost .008" taper and were not level to each other, being around .005" off from each other.

After getting the top, sides and ends square to each other so I had true reference for truing the bottom of the dovetail that's where I ran into the hard spots. I got a 2" carbide insert facemill and it went right through it and did a nice job. I have no idea if impurities float to the top or bottom or just got lucky with all my cuts until the bottom of the dovetail. I got a HSS dovetail cutter for truing up the dovetails. Got it before running into the hard spots so who knows what will happen.

 

[Stefants]

Well, it has been slow going on my concrete work. I will still be playing with that for a while. That does not stop me from thinking ahead and looking forward to a time when I am dealing with more traditional machine tool kind of stuff

At the moment, I am keeping my eyes open for a machinist’s level. Is there any reason that I would want a standard level rather than a frame level? It seems that the frame level offers the ability to register to a horizontal or vertical surface, while a standard level is a one-trick pony. Is there any functionality lost by getting a frame level instead of a standard level? It does not seem to be the case, but maybe I am missing something.

Sent from my iPhone using Tapatalk

 

[C-Bag]

I would like to find a chunk of cast iron to use as a reference comparison as I investigate the properties of various concrete compositions. The easiest thing I have come up with so far would be to cannibalize a cooking vessel. I am not sure that cast iron is representative of machine tool cast iron, though, and it’s not my preferred dimension to work with. I see that I can buy a disk of continuous cast gray iron on eBay (and then pay pretty much the same cost over again to ship it). That would work and is my leading candidate at the moment (but again, I’m not sure that’s the best analog for machine tool cast iron). Any suggestions as to where I might find a piece of scrapped cast-iron suitable to my purpose? I am looking for something that could yield a rectangular slug about 5 inches long, 2 inches wide, and a half inch thick. Thanks for lookin’

Just now for some reason I remembered this but I don't know if you found what you were looking for in cast iron but add to keep on the look out list is dead table saws. I ended up scrapping the one I got off of CL and I ended up using almost everything for other projects. Including the cast iron top and wings. The wings I bolted together and made a really nice flat for my welding table. Because of the webs of the casting it has really worked out for working on odd shapes and for clamping. It kills me years ago I had a neighbor who cleaned out his shop and threw away probably 4-5 sets of cast iron wings off table saws. At the time I couldn't think of the thing to do with them. Hindsight it killer 20/20.

 

[C-Bag]

Well, it has been slow going on my concrete work. I will still be playing with that for a while. That does not stop me from thinking ahead and looking forward to a time when I am dealing with more traditional machine tool kind of stuff

At the moment, I am keeping my eyes open for a machinist’s level. Is there any reason that I would want a standard level rather than a frame level? It seems that the frame level offers the ability to register to a horizontal or vertical surface, while a standard level is a one-trick pony. Is there any functionality lost by getting a frame level instead of a standard level? It does not seem to be the case, but maybe I am missing something.

checking the spec's it has better spec's than the precision level. The only possible difference is reviews said the other precision level was certified, but only in the reviews and I don't see if it says this one is certified. Seems like a deal as those frame squares are usually very expensive.

Sent from my iPhone using Tapatalk

 

[Stefants]

Just now for some reason I remembered this but I don't know if you found what you were looking for in cast iron ...

I bought a piece of continuous cast iron from eBay. It should let me get the comparison I’m looking for. Thanks for your input


Sent from my iPhone using Tapatalk