Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- 7x12MiniLathe
- Messages
Search
|
Re: Warco WM180
andrew franks
Marty, the overall width of the bed is a tad under 4", so I suppose it falls in your "toolroom" category. There are two raised prisms (thus, the saddle must be different from a minilathe), the one on the back of the bed being smaller. I'll sketch up a cross-section and mail you direct with more exact measurements - I can't post a sketch on here, and this is getting a bit OT anyway.
Incidentally, for their minilathe, Warco boast "USA made, high qualiity printed circuit boards for long term reliability". Interesting, though we run on 230v over here, rather than your 110v, so you might need a transformer, even if you could locate the manufacturer. Andy Marty N <martyn@...> wrote: Andrew Franks writes: <snip> My "Warco WM180" is 7x 12, and shares a lot of features (saddle and everything above it) with a regular mini-lathe. <snip> Andy this snippet could have been more timely for me. Could you do me a favor and measure the width of the bed please and post back. Thanks. Looks like a very nice machine and I wish I would have seen this before starting my project machine. Marty --------------------------------- New Yahoo! Mail is the ultimate force in competitive emailing. Find out more at the Yahoo! Mail Championships. Plus: play games and win prizes. |
|
Re: General Info
--- In 7x12minilathe@..., "Marty N" <martyn@...> wrote:
considered "heavy duty" lathes. Those whose beds equal center height are considered "tool room" and those whose beds are narrower than the center height and considered junk (hobby?). Seig 7" machines are about 3.25" across the bed, depends where you measure ;( Hi Marty, Useful comments re saddle adjustment priorities. Thanks. Re the bed width, I can read that 2 ways. It either puts the Sieg 7x just on the junk side of "tool room" and close enough to be worth investing some effort into. Or it puts the Sieg 7x just a whisker short of "heavy duty". Well, it ain't the latter! John |
|
Re: General Info
Gordon
Marty:
toggle quoted message
Show quoted text
Your descriptions would certainly fit with my experience. My big LeBlond at work had a 24 inch center with ways about 30 inches apart. the smaller LeBlond was almost equal, and considered a tool room lathe. The same type ratio applied to our two American Pacemaker machines. The 16 inch had ways about 22 inches apart, and the smaller unit was more "square". Could really take some metal off with those machines, miss them now that I only have a small Prazi at home. Gordon martyn@... wrote: Group: I do allot of research building my machine and find much of the sought information very hard to come by. I had posted a request a few days ago about saddle gib adjustment dimensions and thankfully, no one replied. I say that because I would have stopped rooting around had I received an answer which would have been a lost opportunity to learn something. There is a fellow on my Southbend site who has a shop that rebuilds old lathes. Much of the knowledge on the net being geared toward the rapid machining world of CNC seems to have old manual machine information disappearing at a rapid rate and its nice to run into someone like Turk who is old enough and experienced enough to remember "when it was". |
|
Re: General Info
G'day Marty.
toggle quoted message
Show quoted text
Thanks for that, I now know what to look for in my next lathe! Perhaps somebody could "improve" a Sieg by puting two beds side by side. I noted your comments about the WM180, it seems a much better machine. Warco also have a more typical 7x12 for which they now offer a cam lock tail stock which appears to have a longer foot. They may be able to supply these as spares. I don't recall many machines, and I've seen a few, where the bed was much wider than the centre height except for some monsters in the shipyard machineshop annex. Regarding CNC, I would have thought that would be more fussy with set up than normal where the operator can compensate. Keep up the ferreting. One good turn deserves another. Regards, Ian " Loosely, machines with beds wider than center height are considered "heavy duty" lathes. Those whose beds equal center height are considered "tool room" and those whose beds are narrower than the center height and considered junk (hobby?). Seig 7" machines are about 3.25" across the bed, depends where you measure "
|
|
Re: soluble oil
Michael Taglieri
If I had room for a 20 liter drum of oil, I could've bought a bigger
toggle quoted message
Show quoted text
lathe. Mike Taglieri miket--nyc@... Everyone has his reasons. - Jean Renoir "The Rules of the Game" I did a basic machining course last year at CIT here in Canberra, and
|
|
Re: General Info
Marty N
Group:
I do allot of research building my machine and find much of the sought information very hard to come by. I had posted a request a few days ago about saddle gib adjustment dimensions and thankfully, no one replied. I say that because I would have stopped rooting around had I received an answer which would have been a lost opportunity to learn something. There is a fellow on my Southbend site who has a shop that rebuilds old lathes. Much of the knowledge on the net being geared toward the rapid machining world of CNC seems to have old manual machine information disappearing at a rapid rate and its nice to run into someone like Turk who is old enough and experienced enough to remember "when it was". Sleuthing threw old post of his, I found some definitions and dimensions I had been looking for on machine design. Did you know, for example, that Southbend Workshop lathes don't even have a front gib? Me either and I own one, that's embarrassing. Just a keep plate that is part of the apron to keep it from flying off ;) They do, however have some interesting dimensions. Seems as a general rule the rear gib is the work horse. A heavy cast iron fixture that is the same length as the swing of the lathe. Yep, a 10" long gib! These machines, among others of good reputation have a bed width no narrower than the center height of the machine. This keeps, I'm told, the cutter and work not only inside the bed rails, but inside the inner face of the "V", thus all force is basically down and on the back of the "V" on the front and up on the rear with a slight polar moment that the "V" and long rear gib takes care of. Loosely, machines with beds wider than center height are considered "heavy duty" lathes. Those whose beds equal center height are considered "tool room" and those whose beds are narrower than the center height and considered junk (hobby?). Seig 7" machines are about 3.25" across the bed, depends where you measure ;( Adjusting machines of these dimensions then becomes, whatever on the front and as little as possible on the back gib with drag the limit. Interesting! Marty |
|
Re: Motor Temp Rise on the HF 8x12-14
Michael Taglieri
My copy isn't handy so I can't confirm this, but I think there's a
toggle quoted message
Show quoted text
section on electric motors and their acceptable temperature rise in Machinery's Handbook. Mike Taglieri miket--nyc@... Everyone has his reasons. - Jean Renoir "The Rules of the Game" On Sat, 10 Mar 2007 09:22:51 -0800 (PST) Druid Noibn <druid_noibn@...> writes: Hi All,
|
|
Re: THREAD CHASING
By the time you get spindle & LS at exactly the right place you'll
have spent far more time than if you simply reversed with the LS engaged. Cutting integer imperial threads with an imperial LS there are lots of positions where things line up. When you start getting into n 1/2 threads (like some pipe threads) it gets more restrictive. When you're cutting bizarre decimals, like metric approximations, it's functionally impossible to get things lined up for subsequent passes. In practice, it's quicker to cut threads on these machines by using a handcrank on the spindle & keeping the half-nuts engaged. If it's a relatively long thread, you can use the motor to return to the starting point for each pass, taking care to not get hit by the handcrank. Roy --- In 7x12minilathe@..., "steam4ian" <fosterscons@...> wrote: position and the LS at a set position for a repeatable outcome. The setpass. Subsequent passes would require the saddle to be against the stop,That's cuttingessentially how the thread chasing dial works. If you were athethread that required engaging the half nut at any line it meansthat thelead screw and spindle are linked in multiples of your lead screwpitch. #3offsetposition is the right place it's possible that the spindle is 90degreeoffset for the #2 position, 180 for the #1 position and 270 forthe #4 position.that |
|
Warco WM180
Marty N
Andrew Franks writes:
<snip> My "Warco WM180" is 7x 12, and shares a lot of features (saddle and everything above it) with a regular mini-lathe. <snip> Andy this snippet could have been more timely for me. Could you do me a favor and measure the width of the bed please and post back. Thanks. Looks like a very nice machine and I wish I would have seen this before starting my project machine. Marty |
|
Re: THREAD CHASING
andrew franks
Ian, I don't think it would work, because what you are trying to accomplish is to get all the changewheels back, relative to one another, into the same "start position", and for threads foreign to the leadscrew this magic moment occurs only rarely because of the introduction of 57T or whatever into the train. It's something to do with highest common factors, or lowest common factors, I think (school was 40 years ago).
But do try; if your method works in practice, I will be delighted to be proved wrong! Andy. In vino veritas (hopefully) steam4ian <fosterscons@...> wrote: G'day John et al. Thank you for replying. I have had a few moments to digest what you are saying. Spindle angle is also important in the equation. Thus the Spindle must be at a set angle, the saddle at a set position and the LS at a set position for a repeatable outcome. The set position of the LS is implicit in the half nuts being able to close (assuming a single start thread on the LS). Missing from my assessment was the spindle angle. So you set up by putting the saddle against the stop, rotate the lathe by hand to engage the half nut, mark the spindle against a reference, mark the LS against a reference then take the first pass. Subsequent passes would require the saddle to be against the stop, the spindle to line up with its reference and the LS marker to line up with its reference, engage the half nuts as the marks line up. Please comment. One good turn deserves another. Regards, Ian --- In 7x12minilathe@..., John Dammeyer <johnd@...> wrote: specific point when the spindle is at an equally repeatable location. That'sa thread that required engaging the half nut at any line it meansthat the lead screw and spindle are linked in multiples of your lead screwpitch. #3 position is the right place it's possible that the spindle is 90degree offset for the #2 position, 180 for the #1 position and 270 offsetfor the #4 position.that the nut would have to be engaged at the #1 position the firsttime. The 1.27 position the next time and so on. --------------------------------- New Yahoo! Mail is the ultimate force in competitive emailing. Find out more at the Yahoo! Mail Championships. Plus: play games and win prizes. |
|
Re: 7x12 capability
andrew franks
Hello Chris and Ian,
Don't worry about the name, Ian - I'll answer to anything. My "Warco WM180" is 7x 12, and shares a lot of features (saddle and everything above it) with a regular mini-lathe. It's twice as heavy, though - turns the scales at 11 stones (for US readers, there are 14 lbs to a stone, and for Aussies and those influenced by Napoleon it's 70kg). So, though the bed is more massive, it isn't exactly portable. From what I read in this group, it shares some of the features - or rather lack of them - of 8 x and 9 x machines. Notably, there's no tumbler reverse, but I'm working on that with some components which arrived with commendable speed from both LMS and ArcEuroTrade (LMS got them across the pond within 7 days, and AET got them to me by post 20 hours after my order)). So, Chris, unless like me you are retired and can spend time on accessorising machine tools, I reckon you might be better getting a standard mini-lathe. I get the feeling that there are fewer complaints about the Sieg machines bought in the UK from people like Chester than about those bought in the US, but I may be wrong. Andy steam4ian <fosterscons@...> wrote: G'day Chris. CORRECTION. The guy was Andy Franks not Alan. My apologies Andy. One good trun deserves another. Regards, Ian --- In 7x12minilathe@..., "steam4ian" <fosterscons@...> wrote:
--------------------------------- New Yahoo! Mail is the ultimate force in competitive emailing. Find out more at the Yahoo! Mail Championships. Plus: play games and win prizes. |
|
Re: THREAD CHASING
G'day John et al.
Thank you for replying. I have had a few moments to digest what you are saying. Spindle angle is also important in the equation. Thus the Spindle must be at a set angle, the saddle at a set position and the LS at a set position for a repeatable outcome. The set position of the LS is implicit in the half nuts being able to close (assuming a single start thread on the LS). Missing from my assessment was the spindle angle. So you set up by putting the saddle against the stop, rotate the lathe by hand to engage the half nut, mark the spindle against a reference, mark the LS against a reference then take the first pass. Subsequent passes would require the saddle to be against the stop, the spindle to line up with its reference and the LS marker to line up with its reference, engage the half nuts as the marks line up. Please comment. One good turn deserves another. Regards, Ian --- In 7x12minilathe@..., John Dammeyer <johnd@...> wrote: specific point when the spindle is at an equally repeatable location. That'sa thread that required engaging the half nut at any line it meansthat the lead screw and spindle are linked in multiples of your lead screwpitch. #3 position is the right place it's possible that the spindle is 90degree offset for the #2 position, 180 for the #1 position and 270 offsetfor the #4 position.that the nut would have to be engaged at the #1 position the firsttime. The 1.27 position the next time and so on. |
|
Re: THREAD CHASING
What Andrew said!!!! and much better than I did and I haven't been to
toggle quoted message
Show quoted text
the pub. 8-( John Dammeyer Automation Artisans Inc. Ph. 1 250 544 4950 -----Original Message----- |
|
Re: THREAD CHASING
andrew franks
John's right. When a leadscrew is used to cut a pitch of its own "nationality", the right place to engage the half-nuts turns up frequently. Imagine holding two rulers, ruler 1 graduated in 16ths of an inch (representing an imperial leadscrew) and ruler 2 graduated in (say) 28ths (representing a 28 tpi thread you want to cut). The graduations will coincide exactly very frequently - every quarter inch (because 4/16 = 7/28). So,the right place to engage your leadscrew, as indicated by your thread dial indicator, occurs very frequently.
toggle quoted message
Show quoted text
Now, imagine you want to cut a 1mm thread, and that you have a 127 tooth gear to do an exact conversion from your imperial leadscrew. This time, ruler 2 is metric, and you will only get an EXACT coincidence of the graduations every 127 inches (10' 7"). The "right place" is only going to turn up infrequently on your TDI, and you will need a microscope to distinguish it from all the near misses which will turn up while you wait for it. Of course, you haven't got a 127T gear, so you have to use some fancy geartrain involving 57T, 42T, or whatever to get something which is almost, but not quite, 1mm (25.4 tpi). This might make matters worse. I worked out that, though I could use my imperial leadscrew to cut a 1.25mm pitch thread accurate to 0.02%, the "right place" on a TDI would occur only once in about 30,000 revolutions of the spindle. The gearwheels would only be in precisely the same juxtaposition every 30,000 revs. At an unlikely 1,000 rpm, this would occur every half hour, and would be beyond my eyesight to recognise from all the near misses which intervened. So, if you want to cut a reasonably accurate thread which is "foreign" to your leadscrew, the only option is to leave the half-nuts engaged, and reverse the lathe to get back to the beginning of the cut. Does this make sense? It does to me, but I've only just got back from the pub! Andy John Dammeyer <johnd@...> wrote: Hi Ian, You are making an assumption that when the lead screw is at a specific point when the spindle is at an equally repeatable location. That's essentially how the thread chasing dial works. If you were cutting a thread that required engaging the half nut at any line it means that the lead screw and spindle are linked in multiples of your lead screw pitch. But if you are cutting a thread where the #3 position and only the #3 position is the right place it's possible that the spindle is 90 degree offset for the #2 position, 180 for the #1 position and 270 offset for the #4 position. Now follow that same line of thinking for metric and you may find that the nut would have to be engaged at the #1 position the first time. The 1.27 position the next time and so on. John Dammeyer Automation Artisans Inc. Ph. 1 250 544 4950 -----Original Message----- --------------------------------- New Yahoo! Mail is the ultimate force in competitive emailing. Find out more at the Yahoo! Mail Championships. Plus: play games and win prizes. |
|
Re: THREAD CHASING
Hi Ian,
I have had a knowledgeable response from John Dammeyer but I am not Half the time I don't understand myself either so don't feel bad. ;-) Put a handle on the spindle and install the required for metric gears onto the lathe and walk through some turns with a piece of tape on one of the three jaws so you can keep track of it. You'll find you will be able to engage the lead screw at several places and the jaw will be at the wrong place for some of them. Do it for imperial threads and it's always in the right place. Slow motion.... John Dammeyer |
|
Re: THREAD CHASING
G'day John.
I saw the timing of some of your missals; quite late. With a metric LS the chaser dial does not have the same relationship to the thread as for imperial. Apart from really odd-ball threads or threads with TPI much greater than the LS TPI the chaser dial will always work for imperial even if you can only use one digit as your reference, eg 12 o'clock. I have had a knowledgable response from John Dammeyer but I am not sure I fully understand it. It seems to me that if the saddle is always in the same starting position and the lead screw at the same angle for engagement of the half nuts then the outcome is repeatable. I haven't made a saddle stop yet so I haven't had a chance to try out my theory. I have a picture in my my mind of an old machinist with a chalk mark on the last change gear wheel waiting for it to line up before he engaged the nuts. I am seeking to come up with a way that doesn't need a chaser dial; I am sure a methods must exist other than "granny driving" to reverse out. One good turn deserves another. (tongue in cheek) Regards, Ian --- In 7x12minilathe@..., "born4something" <ajs@...> wrote: way! digit. At least, I think that's right - I had a 3 o'clocker last night and |
|
Re: THREAD CHASING
Hi Ian,
An extended tag - I'd never interpretted that passage quite that way! Just thinking out loud, if you had your RH carriage stop and always started from there, dropping the half nuts in at the first arrival at a digit on the dial (don't care what digit) then successive passes will always retrace as long as you always use the same digit. At least, I think that's right - I had a 3 o'clocker last night and haven't had any caffeine yet! John --- In 7x12minilathe@..., "steam4ian" <fosterscons@...> wrote: have to keep the half nut closed the entire time and reverse the latheout between cuts, also tediuos.between cuts.up a method. It involves using a saddle stop at the RH end of the cutthe half nuts, withdraw the tool and crank the saddle back hardagainst the stop. You set you tool and then gently engage the half nuts byby a circular clip on the lead screw to set indicate when the screwis at the same point of rotation corresponding to the firstengagement. The gib for the half nuts would need to be well adjusted. |
|
Re: THREAD CHASING
Hi Ian,
toggle quoted message
Show quoted text
You are making an assumption that when the lead screw is at a specific point when the spindle is at an equally repeatable location. That's essentially how the thread chasing dial works. If you were cutting a thread that required engaging the half nut at any line it means that the lead screw and spindle are linked in multiples of your lead screw pitch. But if you are cutting a thread where the #3 position and only the #3 position is the right place it's possible that the spindle is 90 degree offset for the #2 position, 180 for the #1 position and 270 offset for the #4 position. Now follow that same line of thinking for metric and you may find that the nut would have to be engaged at the #1 position the first time. The 1.27 position the next time and so on. John Dammeyer Automation Artisans Inc. Ph. 1 250 544 4950 -----Original Message----- |
|
THREAD CHASING
G'day all.
On another topic, John (born4something) and I have been discussing thread chasing dials. If you have a metric lead screw you need a range of pinions on the dial to suit different threads. This is tedious. to cut an imperial thread (with metric lead screw) you have to keep the half nut closed the entire time and reverse the lathe out between cuts, also tediuos. There are two common methods to keep the tool "in the groove" for each pass, namely, using the thread chasing dial or reversing between cuts. I think there is a third method, does anybody know of it? In the wee small hours of the night, my designing time, I dreamt up a method. It involves using a saddle stop at the RH end of the cut (assuming R to L cutting). At the end of each pass you dissengage the half nuts, withdraw the tool and crank the saddle back hard against the stop. You set you tool and then gently engage the half nuts by feeling them into position. This last process would be made easier by a circular clip on the lead screw to set indicate when the screw is at the same point of rotation corresponding to the first engagement. The gib for the half nuts would need to be well adjusted. Comments and advice is sought, over to you. One good turn deserves another. (Luke6:31 Machinists Bible) Regards, Ian |
|
Re: 7x12 capability
Chris,
toggle quoted message
Show quoted text
The best bet is to find a good supplier of unbranded lathes that come from the same manufacturers as the branded models but cost from ?260 - there's no need to pay more. You can get a model with DRO of the spindle speed and a tailstock lever lock and top quality for 270 sovs. Just got to look in the right place! And if you buy on the internet, eBay etc. go and take a look first before buying. Hugh ----- Original Message -----
From: mozziesplat To: 7x12minilathe@... Sent: Wednesday, March 14, 2007 6:30 PM Subject: [7x12minilathe] Re: 7x12 capability Thanks Andy and Ian it sounds like the 7x12 will do the jobs i have in mind for it so i will be putting an order in soon for iether a sieg c3 or a chester conquest i think they are the same machine... Chris --- In 7x12minilathe@..., andrew franks <andyf1108@...> wrote: > > Chris, I had a 3.25" length of 1" diam. aluminium handy, so I've just tried facing it in my 3-jaw, without using undue force to tighten the chuck. In fact, the chucked end was a smaller diam. for a quarter of an inch, so the effective grip was on less than 0.5" of the job. Using modest (3 thou or so) increments, it faced up nicely - can't see any appreciable light getting through when holding it up to the window, against a straightedge.Would be a long job, though, if there was much metal to be removed to achieve the right length, and a travelling steady, as Ian recommends, would enable more ambitious cuts. > Andy > > > mozziesplat <katiechris4evr@...> wrote: > --- In 7x12minilathe@..., "steam4ian" <fosterscons@> > wrote: > > > > G'day Moszziesplat. > > The job is well within the capacity of the 7x12 lathe. My concern > is > > the overhang from the chuck. There is a risk that the work could > skew > > in the chuck due to the cutting forces. Being aluminium doesn't > help, > > it is softer to hold. If the work was any longer I would definitely > use > > a fixed steady to give support at the work face. Use a steady to be > > sure. Consider getting steadies with the lathe, often they come as > a > > cost effective package. > > BTW, with an handle like Mozziesplat and spelling Aluminium > correctly > > you must be Australian. > > > > One good turn deserves another. > > Regards, > > Ian > > > > --- In 7x12minilathe@..., "mozziesplat" > > <katiechris4evr@> wrote: > > > > > > I'm thinking of buying a 7x12 minilathe but i need to know if the > > > standard chucks are cabable of holding 3 inch lengths of 1 inch > round > > > aluminium stock tight enough so that i can face both ends off. > > > I would be a complete novice to this hobby hence the simplistic > > > question. > > > Could anyone please advise. > > > > > > Cheers Ian the work skewing due to the tool forces at the end of the > work were exactly my concerns. What is the maximum diameter of stock > that will fit through the fixed steadies ... You chaps down in > Australia still spell aluminium correctly like us in the uk, the > reason for my handle is another story that doesnt involve dead > insects on your windscreen/shield? > regards, > chris > > > > > > > --------------------------------- > Now you can scan emails quickly with a reading pane. Get the new Yahoo! Mail. > > [Non-text portions of this message have been removed] > ------------------------------------------------------------------------------ No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.413 / Virus Database: 268.18.10/720 - Release Date: 12/03/2007 [Non-text portions of this message have been removed] |
Messages
More
More Options
More
to navigate to use esc to dismiss