bjhines Posted January 12, 2007 Share Posted January 12, 2007 I picked up a beginner lathe for my V-8 project... It is the 8x12 mini lathe that Harbor freight sells for $440... plus shipping... I comes with a few dozen swappable gears for inch and metric thread cutting, one MT2 center, one MT3 center(don't see what this is for), 2 sets of chuck jaws, all the wrenches and allen keys to assemble the lathe http://www.harborfreight.com/cpi/ctaf/Category.taf?CategoryID=267&pricetype= Shipping is reasonable at $61... The problem is.. It weighs 275lbs... I have a commercial delivery address for truck freight.. But I have no forklift for that sort of thing... So I chose to have the store handle it since they have forklifts on site... I used a chain hoist to get it out of my truck... The next problem is the fact that i have no real practical experience with a metal working lathe... I have some experience with woodworking lathes and some woodworking router based CNC machines... But the metalworking aspect brings some questions to mind... especially in the name of safety... The lathe came with virtually NO TOOLING... I purchased 2 sets of cutoff tools.. one 1/4" indexable cutter set... and one 5/16" carbide set... I figure the indexable set is great for repeatable cutting.. and I can grind new shapes on the carbide set... I am looking into my options for inside cutting... I think I need a bore bar set... But those things can be expensive... What would you guys suggest for inside boring???... The lathe did come with 2 centers... one MT2 and one MT3... I can see how the MT2 fits into the tailstock... But what the hell is the MT3 center for???... it makes no sense.. the only thing it would fit into is the lathe chuck... and what good would that be??? Quote Link to comment Share on other sites More sharing options...
Darrel Posted January 12, 2007 Share Posted January 12, 2007 not sure if this will help, but it a lot of useful info in general about the mini lathe and mini mill. http://www.mini-lathe.com/ Quote Link to comment Share on other sites More sharing options...
lbhsbZ Posted January 13, 2007 Share Posted January 13, 2007 Check out www.littlemachineshop.com They have everything you will ever need for your new lathe. I have a 7x12 mini-lathe, as well as the mini-mill. Your lathe is much heavier duty than mine, so it should be much easier to work with....mine is kinda flimsey for what I do with it. www.mini-lathe.com is also a great site, and will get you up to speed with basic procedures. Start saving up for the 4x6 bandsaw and the mini mill....in only a few short weeks of playing with the lathe, you will no longer be able to go through life without the mill and bandsaw. I've made everything on my little lathe, from spherical bearing conversions to camber plates. Last night I made the spacers to use a 12mm R200 diff with a 10mm R200 ring gear, and I machined down the OD of the front bearing retainer on my T-5 transmission to fit inside my new steel bellhousing. Hell, I've even used it to polish door knobs. Quote Link to comment Share on other sites More sharing options...
bjhines Posted January 13, 2007 Author Share Posted January 13, 2007 Thanks guys.. I found those websites... I was hoping some of you might have some better ideas.. more Hybridz oriented functions and accessories... like how to incorporate grinding tools into the function of the lathe... lbhsbZ... That is exactly what I am working towards... The mill is next I have a pretty well outfitted shop.. But I am tired of farming out small parts work... The lathe and later a mill will round it out fairly well... My first project... Changed the I.D. of some coilover sleeves I purchased to fit the 240Z struts.. Well... they didn't.. but now they do.... I had to make a custom tool from one of the cobalt cutters... It was pretty easy.. I mounted it and back ground the rear of the tip to clear the workpiece inside... then I ground a tiny radius on the 90* cutting edge to make a step with an inside radius... It also makes a nice finish on the workpiece... Chucking those coilover sleeves is tough... they are flexible because they are thin... but the 3 jawed chuck did a fine job on these low tolerance pieces... I was at least as accurate as the original machinework before anodizing... I actually forgot to oversize it slightly and had a really tight fit.. so I had to rechuck both ends again and make a last pass.. I was able to get them to within 1 thou accuracy every time with a dial guage... it only took me 5 minutes making minute adjustments with my chip brush handle.. then a final check after tightening... Quote Link to comment Share on other sites More sharing options...
MONGO510 Posted January 13, 2007 Share Posted January 13, 2007 The #3 MT center probably fits in the Headstock after you remove the chuck. You would use it to cut between two centers. You can offset the tailstock and cut a taper. Should be a lathe dog there somewhere. Quote Link to comment Share on other sites More sharing options...
datsunlover Posted January 13, 2007 Share Posted January 13, 2007 Cool little lathe! I will eventually want a small lathe and mill in my shop.. but right now, I don't have much of a shop yet anyway. (1.5 car flat roof non insulated garage.. yuck) I can tell you one thing about a metal lathe though, (even a little guy like that) PAY ATTENTION!! Man.. bad things can happen so fast, and you don't have much time to react. As far as saftey, mostly common sence, as with any tool; Never stand directly in front of the chuck, and don't wear any loose clothing/jewlery. Always make sure evrything is tight (tooling, chuck, tailstock clamped if in use, ect) and know where the E-stop is BEFORE you start up. For boring, there are a few options. If you have to get in a long ways, you need a bar. You can buy them, or build your own depending on how big the hole is to start with. (although a mill is handy to help build these) Ex; a piece of bar stock with a slot in one end and a few set screws, to hold a small lathe cutter makes a great boring bar. If the depth isn't to deep, a normal cutter stuck out of the tool post will work well, although the heavier a cut you take the more likely it is to move. You really should get some reading material/info on machining.. you need to know how diffrent metals cut at differing speeds & feeds, proper ways of seting up for various operations.. There are a few basic formulas for proper RMPs, diameters for threading, ect. What you've done looks ok so far, although a bit scarry.. you're lucky they didn't rip out of the chuck as you were cutting them! Really, you need a proper set of 'soft jaws' for things like that and they could be a bit longer, but hey.. you use what you've got. Quote Link to comment Share on other sites More sharing options...
bjhines Posted January 14, 2007 Author Share Posted January 14, 2007 Thanks Datsunlover... You are right.. the chuck is really inappropriate for the long, thinwalled sleeves... But I tool my time and made small cuts with a really slow feed rate at around 150RPM... I have the geartrain set up for turning a smooth surface... But I hand fed all the cutting on the coilovers because I was making that step.. I did not want it digging into the step and going straight to hell... I have a lot of custom woodworking experience... I am used to working with lathes of a different sort... I will say that the speeds are MUCH higher on a woodworking lathe.. and the parts are typically >36" long... I have a healthy respect for the woodworking lathes.. The metalworking/machine lathes seem much less dangerous... Quote Link to comment Share on other sites More sharing options...
BlackBeaut Posted January 14, 2007 Share Posted January 14, 2007 One thing to be aware of is that 3 jaw self centering chucks aren't necessarily as accurate as you may think, so you can easily end up boring a hole and find out that it's not actual concentric - bleedin' annoying! Other things to learn about are cutting speeds and feed rates, which change depending on the cutter material, i.e. HSS needs a slower rpm than carbide cutters. Check these links: http://en.wikipedia.org/wiki/Cutting_speed http://www.roymech.co.uk/Useful_Tables/Manufacturing/Turning.html A good forum with some knowledgeable guys on here: http://groups.google.co.uk/group/uk.rec.models.engineering/topics?lnk=li Mod you lathe here (well this is a site about hybrids ) http://www.stellar-international.com/lathesf6.html Fix that crummy 3 jaw chuck so it can run true: http://warhammer.mcc.virginia.edu/ty/7x10/vault/Lathes/7x10-7x12-Projects/SetTruBackplate/'>http://warhammer.mcc.virginia.edu/ty/7x10/vault/Lathes/7x10-7x12-Projects/SetTruBackplate/ I'm planning on doing this soon to mount a 6" chuck on my Warco 300, which I generally deem to be a sack of crap when it comes to accuracy. Same guy has lots of good links you should check out: http://warhammer.mcc.virginia.edu/ty/7x10/ Cheers, Rob Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 15, 2007 Share Posted January 15, 2007 I've an old 6" Atlas Model 109...they made allllll sorts of neat attachments for those. Grinding holders for the tool post, milling adapters, etc. You may want to go on E-Bay to get some of the manuals for those attachments---they are pretty easy to fab up. I have even seen people use angle iron attachments for the toolpost and hose clamps to hold 4" Electric Angle Grinders so they can cut hardened axles to different lengths. Now you got the tool, you will find it makes it easier to make the adapters to use it for different things! One of the first projects I did on my Atlas was turn off a full set of replacement bushings so whenever they do wear to the point of needing replacement... Now I sit in wait of my buddy Pete wanting to clean up his storage unit and sell off that 12" Atlas (Clausing) lathe. I almost bought it when the retired, but he decided against selling at the last minute---the guy has every attachment known to man from the original tool catalog for that thing: Milling Attachment, Grinding Attachment, and stuff I've never even heard of before. All still in the original boxes in many cases! Just got to stay in touch and wait... Quote Link to comment Share on other sites More sharing options...
bjhines Posted January 15, 2007 Author Share Posted January 15, 2007 nice info...!!!! I will look for some of those attachments... I need to do some more research... I have been reading Virtual Machine Shop archives http://jjjtrain.kanabco.com/vms/ That is some neat stuff... but a lot of it presents me with a need for a mill... LOL... I mentioned that to my wife and got The Look in response. I did manage to confirm that it will cut a flat face on 1" stock(grade 8 too)... I need to dig around and come up with some larger diameter stock to confirm... Cutting that grade 8 face with a C6 indexable tip moved the carriage on the bed... There is no saddle lock on this lathe... I will have to make one... I had to move the geartrain to stop the crossfeed rod from rotating... Then I engaged the crossfeed threading nut to hold the carriage still... I preloaded it to ensure it did not "settle" against the gears... That seems sufficient for now... I had to stack some square stock and feeler guages to get the tool at the right height... A nice tool holder is definitely on the list... I also noticed that the hardened steel REALLY needs a lot of lubrication... after a really rough first cut and a chipped bit... I indexed a new tip and I coated the face of the stock with cutting fluid and went to town... the oiled surface came out nice and shiny... I also learned to reduce the feed rate as I got to the middle... I also tried a few different speed settings(200-1000 RPM)... I was able to get good results with a variety of speeds... Though it did seem that the slowest speeds would end up tearing/galling the metal giving it a poor surface quality... Quote Link to comment Share on other sites More sharing options...
datsunlover Posted January 16, 2007 Share Posted January 16, 2007 Yup, there's where the 'speeds and feeds' comes in. If you're facing a 1" dia cold rolled bar with a carbide tiped cutter, it should probly be running at LEAST 1000rpm to get a decent finish. You're obviously limited to whatever the speeds on the machine are. Any hardend steel (well, ANY material for that matter) will have a proper 'cutting speed' (Surface Feet per Minuit) and you plug in into the RPM formula to get the theoretical ideal speed for it. Take into account tool steel or carbide cutter, and you'll get a good idea where to start. Also tool HIGHT is important. If it's even a little above center (of the work piece) it will rub and you won't get a nice cut. Actually, you get mush and scraping, possibly a chipped cutter. A little low is fine, but too low you run into two issues; The graduations on the x-feed won't be acurate, or you could smash the tip off the tool. As for the sadle moving around while machining, you're probly finding the limits of the machine.. a ridgid machine is the key really, and a little guy like that will have limits. If the saddle is thick enough, you could drill and tap a threaded hold through it (say a 3/8" or so..) then turn up a little plug of brass a little smaller (about .350" say..) and part it off about 1/8" thick. Drop it in the hole, and screw in your 3/8" bolt. This should lock it fairly well on to the bed way, and the brass won't hurt the ground surface. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted January 17, 2007 Share Posted January 17, 2007 you could make a chucking plug that fits snug inside the tubes so when you chuck up on them they don't deform. You could even make one that they threaded into if youre head stock allowed them to pass through I'd get yourself a decent set of dial indicators to checking trueness and all that if you havn't already. Really helps! Quote Link to comment Share on other sites More sharing options...
bjhines Posted January 17, 2007 Author Share Posted January 17, 2007 I managed to lock the saddle by disengaging the traverse rod gears... then I engaged the traverse handle to hold it still... I preloaded the carriage to get all the slop out... It works very well now and cuts without moving... I am going to make a gear shift mechanism to engage/disengage and reverse this sucker... currently I have to open up the cover and loosen an allen head srew to swivel the gear plate away from the drive gear on the spindle... Then I have to get them correctly meshed again in order to use the power feed... I found some neat ideas on the Web to make this easier... I made some more useful parts last nite... It was fun... It took about 4 hours..lol.. I am learning... These are very low tolerance parts... but I took my time and put a little more into it than was required... They are bushings for my hiem jointed front inner LCAs... The rod-end is 3/4"... the inner LCA bolt is 9/16"... I needed to offset the arm forwards in the crossmember(one bushing longer than the other)... These little parts had to do a lot of jobs and need to be a light as possible... I also wanted to use a stepped bushing design... My local machine shop wanted an hour labor to make them($75)... The steel bushings on top are not wide enough(heavy washers) and they do not allow much offset forwards... on the bottom I made a set out of 6061T6 rod... drilled to 9/16 and turned to fit inside the rod-end with a step... one longer than the other... It was fun.. and my first few turnings with this tool have all been highly useful... Hell the coilover sleeves would have cost at least $100 to modify all 4... and the bushings are worth one hour labor at the machine shop themselves... That is half the cost of the damn lathe already... Quote Link to comment Share on other sites More sharing options...
JMortensen Posted January 17, 2007 Share Posted January 17, 2007 You know about 6 or 7 years ago my roommate bought one of those. I remember asking "What the hell are you buying that thing for?" and when I think back to all the times I could have used one... maybe I need to get one myself!!! Quote Link to comment Share on other sites More sharing options...
bjhines Posted January 17, 2007 Author Share Posted January 17, 2007 The hardest thing to learn for me is definitely geting used to the dials on the lathe... They are all different graduations.. The combination slide is fine adjustment with each mark = 0.001" The cross slide is medium adjustment with each mark(wide marks) = 0.002" The main traverse wheel is coarse adjustment each mark = 0.02" but a big dial with one turn = 0.2" travel It turns out that I didn't really need the combination slide for this job... I takes too many damn turns of the wheel to do anyhting... and I made good use of the power traverse to get a nice even finish... Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 18, 2007 Share Posted January 18, 2007 You know about 6 or 7 years ago my roommate bought one of those. I remember asking "What the hell are you buying that thing for?" and when I think back to all the times I could have used one... maybe I need to get one myself!!! Indeed! It's what my wife said when I bought my Atlas! "It's the little things!" This bushing, that bearing. Buying stainless fasteners in BULK at one length, and then facing them off as you need them one or two at a time, knowing all the while you bought 1000 M6-1.0X60 Button head Cap Screws at a penny a peice instead of 20 cents a piece....and making them all fit the different nooks and crannies around the Z where an M6-1.0 is used... Refacing chisels and punches that have mushroomed... Making specialty "offset" fasteners out of Hex Stock.... Oh, those things come in handy! I'll testify to that... I bought mine for $150 back in 1989 with a three and four jaw chuck, some tooling and a knurling tool, got the full set of gearing for $15 at the Pomona Swap Meet about two months later. I see the same lathe on E-Bay now selling for over $350!!! And mine is in better shape than those in most cases. I'm glad I bought mine. "They Grow on You" LOL Quote Link to comment Share on other sites More sharing options...
pallnet Posted January 18, 2007 Share Posted January 18, 2007 Well mine is a bit larger then that one but all and all you will LOVE having a lathe. My Rockwell was given to me FREE by my uncle with no tooling and a 3 jaw chuck. WOAH!. While typing this and multi-tasking I come accross this... http://cgi.ebay.com/6-INDEPENDENT-FOUR-JAW-LATHE-CHUCK-ROCKWELL-BRAND_W0QQitemZ250073997598QQihZ015QQcategoryZ25292QQssPageNameZWDVWQQrdZ1QQcmdZViewItem KICK AZZ!!!, I GOT ME A 4 JAW CHUCK..... Back to your new tool, enjoy it and never get rid of it unless you're upgrading.. Do the upgrade first though Quote Link to comment Share on other sites More sharing options...
2126 Posted January 25, 2007 Share Posted January 25, 2007 Well mine is a bit larger then that one but all and all you will LOVE having a lathe. My Rockwell was given to me FREE by my uncle with no tooling and a 3 jaw chuck. WOAH!. While typing this and multi-tasking I come accross this... http://cgi.ebay.com/6-INDEPENDENT-FOUR-JAW-LATHE-CHUCK-ROCKWELL-BRAND_W0QQitemZ250073997598QQihZ015QQcategoryZ25292QQssPageNameZWDVWQQrdZ1QQcmdZViewItem KICK AZZ!!!, I GOT ME A 4 JAW CHUCK..... Back to your new tool, enjoy it and never get rid of it unless you're upgrading.. Do the upgrade first though Well, I quess now you'll have a chance to use your dial indicators more often! Nice score on the four jaw. Tom Quote Link to comment Share on other sites More sharing options...
bjhines Posted February 1, 2007 Author Share Posted February 1, 2007 I found yet another wonderful use for the lathe... I cut down some strut tubes for my rear struts... I used the lathe to turn a lip right where the original spring seat was welded to the strut tube... Welded back together with a section removed.... ... Quote Link to comment Share on other sites More sharing options...
blueovalz Posted February 1, 2007 Share Posted February 1, 2007 I highly recommend the "Machinerys Handbook". Even the real old ones will provide all the information you could possibly need in regards to materials, feed rates, etc. Beware though, mine is an old one and it has over 800 pages. It's an excellent book, and can be found on Ebay for a reasonable price for older ones. Quote Link to comment Share on other sites More sharing options...
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