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woodnerd
08-22-2011, 11:17 PM
I've inherited my dad's old Craftsman lathe. I'm just stepping into learning machining, how do I check out this lathe to see if it's in good condition? It basically runs and I've used it to do some basic turning and threading. I'm just concerned that when I'm having problems, how will I know that I'm not fighting an out-of-shape machine?

http://www.thewoodnerd.com/blog/wp-content/uploads/2011/08/DSC7801.jpg

vpt
08-22-2011, 11:25 PM
Looks like a good solid low hour machine! Any problems you come across are because of the user. :P

Tony Ennis
08-22-2011, 11:27 PM
Just oil it and use it.

That thing's beautiful.

woodnerd
08-22-2011, 11:32 PM
Well, I spent a lot of time cleaning and repainting it, it didn't look that nice when I started :)

It's almost 40 years old and I really don't have any idea how much my dad used it. For all I know, it's severely out of alignment or whatever. So I was hoping to get some things to check out.

Scottike
08-22-2011, 11:53 PM
That's a great looking machine, you shouldn't have any problems with it, but if you do, feel free post. There's a lot folks here with a lot of experence that are glad to share.
Here's a link to an article on evaluating a lathe. It's mainly focused towards someone interested in buying, but it has good information on things to check and how to do it.
http://www.mermac.com/advicenew.html

gwilson
08-23-2011, 12:00 AM
That was like my first lathe. A good,solid toolpost will help performance a good deal.

Carld
08-23-2011, 12:29 AM
I must say that you did a fine job of cleaning and painting it. I would say get a Starrett 98 level and check it to be sure there is no twist in the bed. If there is adjust it out and then start using the lathe. If there are any issues they will show up as your using it.

Cheeseking
08-23-2011, 12:43 AM
One quick thing you can do is run the carriage all the way over to the tailstock then tighten the lock just enough to still be able to move with the handwheel. Then crank the carriage towards the headstock and see how much it loosens. It's not a definitive test or anything but the more it loosens up as you go indicates more wear.

dp
08-23-2011, 01:09 AM
It may be out of "what ever" but it isn't worn out. It is really hard for a guy raising a family or chasing a hobby to wear out an iron machine. Not impossible, but unlikely. Don't worry about any broken parts you find - Nothing with the Craftsman label is unrepairable, thanks to Ebay and Craigslist.

There are some tests and adjustments that can be done to compensate for misalignment and wear. Get the manual and study it then pop back in with questions.

Couple o` things in your favor - it's a gearbox lathe, it's a Craftsman (way lots of parts available), and you have no investment but time in it.

There are some tests you can run on it and which are also good first-year student educations.

* Turn a dowel between centers - check for taper
* Go through a complete alignment using the manual
* Make a project - something interesting that requires threading, facing, turning, and a taper.
* Repair a household item such as a lawn mower, for example, by creating a replacement part

If you are very lucky you may find a project your dad started but didn't finish. Finish it. I'm 66yo and did that just last year, 12 years after my dad passed away. It was a very smile generating thing to do.

Black_Moons
08-23-2011, 02:18 AM
Play around with it. its likey fine. Don't adjust the headstock. Even if it is misaligned, you can still do wonderful work on it, and learn the basics. More then likey its fine, maybe the bed is a little twisted (Adjust with leveling feet, Seriously), or tailstock misaligned. (Both common things that will produce taper) Headstocks are bolted down pertty securely (often onto rails or ways), and should be the last thing you would ever want to adjust. Definately don't do it as a beginner, and definately not untill its 110% confirmed to be the headstock.

polepenhollow
08-23-2011, 02:42 AM
The machine looks fine from your pix.
I basically paid off the mortgage from our first house using one of these.

K Liv

sasquatch
08-23-2011, 10:18 AM
Agree with the previous posters who commented on the fine looking restoration job!!

gwilson
08-23-2011, 11:02 AM
Those pot metal half nuts wear out easily. I always meant to make a better pair for mine out of brass. The lathe uses the half nuts for both "sliding" and threading,unfortunately.

I was pretty frustrated with mine since I could take only very light cuts with mine. The bed is way too flexible. Plus,it would usually turn a bit of taper,since I didn't want to make the tailstock too tight between the ways. It is adjustable for how it fits between the ways. I preferred to have it "slidable" rather than taking effort to push it. I was afraid that if I got it adjusted too snugly,it might wear the inside surfaces of the ways too much.

I did do some nice work with mine,never the less. It just took a lot more time.

Think about making better half nuts soon. I wore out a pair every several months WHEN they could be purchased.Use an angle plate attached to the face plate to hold the brass ones when you are boring them out. Saw them apart after you get them bored and threaded. I suggest making a short length copy of your leadscrew to use as a gauge when threading your brass copies so you will know they will fit when you take them off the lathe.You can use a couple of pieces of small round steel that will fit down into the threads of your leadscrew-but NOT bottom out-as gauges when measuring your copy. Just mike their outside diameter when they are inserted into your leadscrew,and into your copy. Thing is,your threading tool will HAVE to be accurately ground. You need to buy an acme thread gauge to grind your tool by.

My next lathe was a 10" x 24" Jet,which was a revelation in power,depth of cut,and accuracy in turning long pieces.

If time is not an issue,you can do good work on the lathe.

john11668
08-23-2011, 07:11 PM
Wish my dad had left me one like that!