Scraping newb to tinker with cheapo import lathe?

[T.Hoffman]

I have few pieces to make out of brass on my lathe at work, which make up a tiny tubing end forming tool that inserts into a soldering iron. Biggest dia of the parts is .200-ish. And a lot of features are much smaller.

I made up one rather than buying from the vendor that sells the tool- they want $900 for this!! Has a few critical diameters and radii, but it turned out great and I probably have 6 hours into making all the parts of this tool.

Now I'm being asked to make two more of these tools.... Because the parts are pretty tiny to be working on a bigger 3jaw chuck using shims as to not mar the surface of the brass, and I DON'T have a collet chuck (I keep asking for funds to buy one), we came across a cheapo asian import 7x10 mini lathe for cheap. I figured this would be easier to turn out these tiny parts on that thing, and I can tinker with a new toy in the process.

The dovetails and gibs on this thing are rough. It would work much nicer if these were finished better, I've seen where some guys have used lapping compound to work the dovetails in to a smoother surface. But I though this would be a good thing for me to look at hand scraping. If I screw it up too badly- nothing is really lost and replacement parts can be had for cheap. This isn't hardened material so I think I could do this without needing carbide scrapers?

So with that said, should I try tinkering with this?

I figure the first step I need is some transfer ink and a known flat surface to ink the bottom side of the cross-slide.

I think this could be a great learning process for me, and not much to lose if it doesn't turn out right.

[Scottike]

I see your point about using it as a learning experence and I could see it being a good 1st project.
The only thing I would question is when it's all said and done, is the machine actually worth the time and effort to scrape? (other than for educational purposes)
Or would you end up with a sow's ear trying to be a silk purse, assuming no mis-steps?

[T.Hoffman]

....is the machine actually worth the time and effort to scrape? (other than for educational purposes)

The machine really isn't worth the time/effort to be putting into the machine as a long-term investment
But rather as a "get my toes wet" into the process for doing other things down the road.

I wouldn't consider attempting a scraping project on a nicer machine with no experience.
And to get some experience, ya gotta start somewhere....

[Ryobiguy]

Yes, one does need to start somewhere, but perhaps it would be wise to get a hunk of cast iron and get the feel of removing metal first, before digging into a machine tool, even if it is el cheapo mini-lathe.
If you've got a grinder that can sharpen carbide, then it would be worth it to make a carbide scraper, even if you don't end up scraping the whole lathe.

[jdunmyer]

T.Hoffman,
Many owners of these lathes have improved them dramatically by various simple procedures. Some have scraped the carriage and tailstock castings, others have lapped them, while others have used abrasive cloth wrapped around a file. Anything to smooth the surfaces seems to help a lot. Making a new gib for the carriage is often necessary, as it's easy to break the original when adjusting it.

I found that a bit of sanding and filing of the carriage and cross-slide, then adjusting things properly made a huge difference in the operation.

If you're going to thread on the machine, it will help to use a hand crank, rather than try to do it under power. "Slow" on this lathe is still fairly fast, at least to me.

See: http://www.toolsandmods.com/ralph-patterson.html
and: http://www.gadgetbuilder.com/index.html
and: http://mikesworkshop.weebly.com/
and: http://www.mini-lathe.com/
also: http://www.littlemachineshop.com/

There are other sites with tips and techniques.

I bought a H.F. 7X10 a number of years ago and used it a lot, recently upgrading to a MicroMark 7X14. As my other lathe is a LeBlond 19X54, you can imagine how handy this little thing is for small work. I've even fixed mine up with a box to cover it, much like a portable sewing machine, so I can carry it along to Buckley, MI.

[PeteM]

You wouldn't want an aspiring surgeon to start cutting away before carefully diagnosing the problem; and it's pretty much the same with scraping. You'll need a surface plate, angled straightedge, measuring instruments etc. to survey even your tiny lathe and then monitor progress. No problem with this as a first project, but don't just dive in looking for high spots. Practically speaking, the amount spent to set yourself up for scraping could buy a pretty nice collet setup.

On edit: One possible and not very professional way to improve the dovetails would be to first get an angled straightedge (sometimes large wood planer blades can be used, if found cheap and in immaculate condition). Then carefully spot and scrape your dovetails. This won't correct geometric defects, but it may make the cross and compound feeds work a bit more smoothly.