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Discussion Starter · #1 ·
I've been searching the web for help in buying a lathe for framebuilding. I think I have found most of what is online regarding this topic so now I'm turning to you.
I don't see many threads here that mention what is being used by people who make bikes. But if I missed them please show me the threads.
As with mill's it seems like 'bigger is better' but for framebuilding purposes i'm not sure how big is overkill and how small is just too small for what I need to do.

I build in steel and would like to face head tubes, fork crown races, and have the ability to ream BB's or seat tubes. I can also see wanting to make my own head tubes similar to PMW's but with a thinner wall. Most these can be done by hand but I've yet to find a good/accurate way to face head tubes before loading in the frame fixture without a lathe (anyone...? I've tried an endmill on my mill, machinists square and file, belt sander).

Soon I am moving to northern California and have a shop that can handle the weight of a big lathe, but don't see needing one for what I want to do. I would like to spend less than $2K (ideally less than 1K) and buy a used US-made lathe but would consider an import like Grizzly or Enco if it's going to be too much work & money to rebuild used one.

So those of you with a lathe put yourself in my shoes. What would you get if availability weren't an issue? Not just the size of lathe in swing and bed length, but brand, spindle bore diameter, belt-drive or ...?, drive speeds?, etc. What kind of tooling should I expect to get for what I want to do? Would you wait for a local option or try to ship cross country if the lathe was worth the extra cash? Anyone in CA that knows the market? Craigslist or eBay? Other places to look?
For example, here's a CL search in the area.

Lastly, what resources exist to help me figure out speeds when running different processes? What speed do builders run when facing 37mm head tubes vs. 44mm HT's? Do you need a steady-rest to face long head tubes if the spindle bore is too small?

thanks for any help!
 

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I know very little about this sort of this but am also in the market for a lathe. I don't have much space so I'm looking for 9"x20" or thereabouts, which is the biggest I can realistically fit. I used to think a 1.5" bore was about as big as you'd want for bicycle stuff, but then 44mm HTs, BB30 and all that other nonsense came out. Stepping up to a 2" bore seems hudge by comparison.

For facing head tubes, I never thought a chop saw was all that bad (sacrilege, I know).

I don't know the exact resources, but there are machinist books that will list speeds for different materials and diameters. I don't know where you'd find information on exactly what's ideal for something as hard as OX Platinum, but you'll figure it out.

As far as I can tell from the catalogs, Gizzly = Enco. The disconcerting this is that it also looks like both = Harbor Freight. Though I suppose clones could easily be mistaken for each other whereas the real quality could be very different. Maybe someone who actually knows what they're talking about will chime in.

Finally, lathes can be sorta terrifying. Don't know what you're level of experience is, but for safety's sake, I'd look for a community college class or something (see also figuring out what speeds to run).
 

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Whit,

Purchasing equipment is so subjective, your perspective of needs before owning a lathe and your ultimate requirements can be sooo far apart as you have yet to begin to build experience, knowledge, and awareness of just how much can be done with the tool.

I'm gonna throw out some parameters that I'd suggest as minimums. Understand that I am looking from a general machine capability with a scope that will include bicycle fabrication work, though that will only be a fraction of what you will ultimately use the lathe for.

Though size is a concern for you, it is often a necessity for rigid turning and fabrication. Stay away from "bench top" models...they are fine for small jobs or hobbiest, but not for long term "bicycle work", fixture fabrication, etc...

I'd suggest a minimum of:

10" x 36" bed
1.5" through spindle
3 and 4 jaw chucks
Tail stock
Quick change tool post
Variable speed from 35rpm to 2000rpm
Screw/thread cutting gear box for both imperial and metric pitches

Plan to spend between 1200 and 1800 dollars for such a unit with some patient shopping. Don't forget to have 3 phase capabilities or a large rotary phase converter for shop power.

As for speed rates for cutting, the Machinist Handbook will give you the fundamentals...experience and time behind the cutter will teach you the rest.

hope this helps,

rody
 

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From experience....I would not do a 9x20.

I have an Enco.......junk. It is so not rigid that it is extremely hard to get good finishes. Through bore is 3/4. ........real nice china quality here-

Save/wait a bit more and pick up Rody's suggestion-
 

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You are 1000% better off buying used American iron than the crap the bargain tooling stores sell. I have bought a lot of used equipment from Reliable Tool in So. Cal. They test and clean the machines, and you can go down ahead of the auction to have them wire them up and try them out. So far every machine has ran with no trouble for many years.

Here is a link to the listings, I will check them out every couple days. The listings are posted about 5-6 days in advance and best of all NO RESERVE.

reliabletools | eBay

I agree with Rody on the spec's.
 

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There's so much to learn when it comes to buying your first lathe (or milling machine). The volume of information to absorb can be overwhelming, especially if you don't have,

1) A knowledgeable friend or someone who can mentor and advise you.
2) Some kind of formal training from a job or vocational school where you've learned your way around the machine and some of the basic techniques.

Without these it can be a bit more of a crapshoot and the chances of getting your ideal machine first time around will be lessened.

I bought an old South Bend 9" lathe four years ago having read up on the subject a fair amount. It was overpriced, undertooled and on the tired side. I know all that now, but not then.
Still, it's been a fantastic learning experience and I've managed to learn how to turn out some good work with it. All used machinery is worn to some extent. Part of the skill of being a good machinist is understanding the processes enough so as to be able to compensate for wear.

Drew's point about HSS cutters for lower powered machines is spot on. I've spent a lot of time learing cutter geometries and how to grind them. Good experience, and it really makes a difference.

When it comes to prices of used machines it's going to depend on the area of the country that you're in. Here in Seattle for example machine's with the spec's that Rody listed above don't come along too often and when they do, will be anywhere from $2500 and up. Assuming decent condition and tooling. Cherry and well tooled they'd be more like $3500 and up, in my experience.

I do think that the import 9x20's can be a good way to bootstrap your way up into learning about lathes and operating techniques. You'll outgrow it very quickly, at which point you can either sell it and get a bigger lathe, or keep it as a dedicated operation type machine, and get a bigger lathe.

Good luck.

Alistair.
 

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I have been using a Smithy lath/mill combo for years now, with no problems. Machine has been rock solid! I needed to "learn" the machine, and its issues (turn the dial .003, it moves .001, etc). I have built alot of things with the lathe, and have never had an issue with it being inaccurate, as long as you know its built in errors, which most likely any machine will have, and can actually use a micrometer.

NOW, if I had the $$ to buy a nice South Bend or other, I would, but this machine has served its purpose for many years with no issues. That said, I wouldnt hesitate to buy another, but this time I would buy DRO, and have the ability for CNC.

For what you want to do with it, a machine like this would most likely suit your needs. Of course the capabilities you need might not be handled well with a smaller machine.
 

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How do you guys feel about a south bend 9" x 36" (I think its 36")? I have the opportunity to pick one up with a TON of tooling for $400.

I don't have money for two lathes, would this one cut it or should I be looking at something bigger?
 

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How do you guys feel about a south bend 9" x 36" (I think its 36")? I have the opportunity to pick one up with a TON of tooling for $400.

I don't have money for two lathes, would this one cut it or should I be looking at something bigger?

If it's in reasonable shape that is great deal. Around here people want $1000 dollars for clapped out South Bends with minimal tooling.
If it's a 9A (with quick change screwcutting gear box) that would be even better. If it's an older model with the manual change wheels it's still a good price, imo. Assuming no major issues.

The 3/4" in spindle bore will be the biggest limiting factor for you from a frame building perspective. You'll have to get good with the steady rest. Not a huge deal, just more time consuming.

Also, this lathe takes 3C collets which top out at 1/2" capacity. For accurate work of larger dimensions, you'll have to get good with dialing in the 4 jaw chuck. Again, not a huge deal, but it just makes this type of lathe more suitable for someone who's time is not money (ie. hobbyist, not so much pro builder).

Alistair.
 

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RCP Fabrication
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Thats basically what I was thinking. I have been using my buddys 16" SB, but its really getting annoying leaving the shop every time I need to turn something down.
 

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RCP, That is an excellent lathe for the money. Of course if your budget is at least a $1000 more (and more likely a lot more than that unless your get lucky) than you want to get a lathe with a bigger through hole. That would be the South Bend 10" heavy or its 13" cousin which has a 1 3/8" spindle hole and can take 5C collets. South Bend is just a few miles south of my shop and I go by where the old company factory used to stand on my way to get paint for frames. They tore it down a couple of years ago. Grizzly bought it out. I try and keep my eyes open for a decent South Bend 10" heavy and their average cost is around $2500 on eBay.

I have a South Bend 9" lathe and find it useful for small framebuilding tasks. You will always be able to get more than your $400 out of it when you find something better. It is a great starter lathe.
 

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Discussion Starter · #14 ·
Thanks all! I'm really grateful for you taking the time to help out.

The general specs from Rody are great. Knowing the variable speed range is new info to me and help narrow my search image.
The links from Drew are invaluable. I've completely studied them already (except the 3rd one...).
TacoMan's link is great and I'll keep an eye out. Not too far to drive if it's a good machine.
The advice from Allstair is hugely helpful. I'm using this forum to answer your #1 :)
and #2 will be answered when I make the move. I have a couple of friends that live there that I can get to help me learn (and move the thing). The guy I bought the house from, and who made the shop, was a machinist and has offered to teach me the basics once I get set up. Too bad he sold his lathe before we made an offer on the house! But neither of them are available to help me choose a specific lathe, and I really was looking for the framebuilder's perspective anyways.

So, it sounds like for the more basic framebuilding tasks of facing HT's and fork crown races (with using a steady rest) you can get away with a 9 or 10" lathe, but it'll just be more time consuming and difficult to do certain things because of the smaller through spindle, smaller bed, and less rigidity? But for doing most anything you'd ever want to do, like making your own frame fixture and other large tooling you'll need a bigger machine.

I can see going with a 9x20" on purpose at first to learn the ropes and eventually (or not) 'grow into' a bigger machine like Allstair kind of suggests. But then again, why make life more difficult unless you have to?
So a question: Allstair and others -- what CAN'T you do on your 9" lathes that you wish you could -- what gives you lathe-envy?
Does anyone make 44mm head tubes on a 9x20?
 

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I can see going with a 9x20" on purpose at first to learn the ropes and eventually (or not) 'grow into' a bigger machine like Allstair kind of suggests. But then again, why make life more difficult unless you have to?
So a question: Allstair and others -- what CAN'T you do on your 9" lathes that you wish you could -- what gives you lathe-envy?
Does anyone make 44mm head tubes on a 9x20?

I mention the 9x20 route in case you live in an area where machine tools are harder to come by used, so at least you could do some turning while you wait for the right machine.

For example, the Seattle market is only so so for used lathes in the 9" to 12" swing size range, but the 9x20's come up fairly often. Used, and in fair shape, you can pick one of these up for less than the price of what you'd pay for a decent replacement chuck for a "real" lathe, so they're almost like an (albeit useful) accessory in a way, rather than an actual machine tool. You can still learn the basics on them though.

If/when I upgrade my lathe I'd like it to be able to use 5C collets. This would also mean I'd be able to fit 1" and 1 1/8" steerers in the spindle for turning crown races, which I currently have to use the steady rest for.
On my budget that means I'd be looking for something like a South Bend Heavy Ten, or one of the 12x36 imports (Grizzly, Enco etc.).

Alistair.
 

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I have yet to find a 5c collet that will actually fit a 1 1/8" steerer a usable distance into the collet. Anyone have a part number for one they know doesn't have a step to smaller diameter than that inside?
 

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I have yet to find a 5c collet that will actually fit a 1 1/8" steerer a usable distance into the collet. Anyone have a part number for one they know doesn't have a step to smaller diameter than that inside?
I don't know of one myself. When I mentioned being able to insert an 1 1/8" steerer into the spindle I was assuming having to use the four jaw.
A good quality 3 jaw, with decent repeatability might work too. Either way, still an upgrade for me over what I currently have to do on my 9" SB.

If there is a 5C collet solution I'd like to know about it too. That'd be handy.

Alistair.
 

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reading comprehension problems here :)

I really like being able to cut tubing to length on the lathe. You have to worry about whip if it's small tubing, but anything over 1" has never been a problem. I have a 6 jaw and a 4 jaw. My six jaw gets all the work. If I really want to dial something in, it is a set-tru chuck so I can dial it in.

I would never get anything done on my lathe if I had to cut tools. I suffered through grinding tools for years, and I came to the conclusion that some of us just aren't cut out for that sort of thing. I get pretty good surface finish with my beater lathe using inserts. High surface speeds is the secret. Sometimes you get better surface finish if you take a heavier cut. That's the sort of thing you aren't going to be able to do on a smaller lathe. I looked at the HF 9x20 yesterday, couldn't believe they were asking $550 for one. I guess you can get a discount with creative use of sales and coupons, but it's not worth it to me.

I also suffered with one of the belt drive 9" Southbends for years. Those things are better than no lathe, but not a lot. I needed the space in my lab so I sent it to surplus sales. My lathe has a D-5 camlock chuck mounting. I think I would hate to have a threaded nose on my lathe, for one thing it's not a good idea to reverse. I keep looking for a decent collet closer, but the money and availability have never been together at the same time/place
 

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reading comprehension problems here :)

I really like being able to cut tubing to length on the lathe. You have to worry about whip if it's small tubing, but anything over 1" has never been a problem. I have a 6 jaw and a 4 jaw. My six jaw gets all the work. If I really want to dial something in, it is a set-tru chuck so I can dial it in.

Yeah, a six jaw set tru is a nice piece of kit. Agreed also on camlock or long taper spindle noses as opposed to threaded. Thread on spindles can be made to work well if you take care fitting the back plate to a plain back chuck (especially the shoulder registration) but still less desirable than more modern chuck mounting systems.


I would never get anything done on my lathe if I had to cut tools. I suffered through grinding tools for years, and I came to the conclusion that some of us just aren't cut out for that sort of thing. I get pretty good surface finish with my beater lathe using inserts. High surface speeds is the secret. Sometimes you get better surface finish if you take a heavier cut. That's the sort of thing you aren't going to be able to do on a smaller lathe. I looked at the HF 9x20 yesterday, couldn't believe they were asking $550 for one. I guess you can get a discount with creative use of sales and coupons, but it's not worth it to me.

The trick I was taught for grinding HSS was to throw away the grey wheels that come with regular bench grinders. They are junk, and the friability/hardness of the abrasive binder is all wrong for HSS.
Surface grinder wheels, around "K" hardness, work well. The central hole diameter of these is 1 1/4" (typically) so you have to make an adapter to step up the size of the grinder shaft to fit.
I haven't found carbide to work well at all for my lathe (small, low power and speed), especially for taking light finish passes. Using HSS I'm able to produce accurate work with excellent finish. The convenience of carbide is tempting though. If I had a bigger lathe with more rigidity, power and higher speeds I'm sure I'd look into it more.


I also suffered with one of the belt drive 9" Southbends for years. Those things are better than no lathe, but not a lot.

I think that's a little harsh but I can see where you're coming from. I feel like a 9" SB is pretty much the minimum when it comes to a compact machine that can do decent work. Limited? For sure, but I know some accomplished machinists who have one in their shop. Not as their main machine but they do real work with it. Obviously, a tired and worn out machine is going to have limited usefulness and there's plenty of those around.

South Bend lathes definitely have their devotees who are fanatical about their lathes. I think many of these people over rate how good these lathes actually are, driving up the prices of used machines and parts.
From my perspective, they're decent little machines. Definitely a useful addition to small framebuilding shop, and definitely a good introductory lathe.

Alistair.
 

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Randomhead
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I would love to have a Heavy 10. Work had one of those and it was a really nice, solid lathe. Much superior to the 9", but a lot harder to get a good one.

You can still find the "in praise of junker lathes" article out there on the web. I agree with the notion that a lathe is better than no lathe. I have a really nice set of ear muffs that broke. Just this morning I turned a pivot and used JB Weld to fix them. I had previously just tried gluing them back together and it failed. Any lathe would have done that job, even the HF 9x20.

Lathe Inserts has some nice hobby lathe tools from what I have heard. I bought some tools from Mesa Tools that have worked pretty well for me.
 
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