avoid; ebay "Mini Quick Change Tool Post Blade Holder Kit Set"

[Shox Dr]

The main body looks to be aluminium, which won't help, also it far too small for your lathe, you need, either a 250/100 or a 250/200. If you have a look on the allendale site you'll find the dims for them all.

Also you've not got enough thread in the nut holding it to the top slide; good rule of thumb for any application is at least 2.5 threads projection.

 

[skotl]

The main body looks to be aluminium, which won't help, also it far too small for your lathe, you need, either a 250/100 or a 250/200. If you have a look on the allendale site you'll find the dims for them all.

Also you've not got enough thread in the nut holding it to the top slide; good rule of thumb for any application is at least 2.5 threads projection.

Yup - wouldn't disagree with any of that

 

[addjunkie]

The smaller the diameter the faster your work needs to be turning. That looked far too slow for a good finish. That looked like a tipped tool, if it was they need to be worked much harder. Study up on cutting feeds and speeds, tool sharpening and rake angles etc, well worth spending a bit of time, you tube as good a place as any to start.

Also you do know about the height the tool needs to be set at dont you, and the quick way to do it?

 

[ukracer]

The smaller the diameter the faster your work needs to be turning. That looked far too slow for a good finish. That looked like a tipped tool, if it was they need to be worked much harder. Study up on cutting feeds and speeds, tool sharpening and rake angles etc, well worth spending a bit of time, you tube as good a place as any to start.

Also you do know about the height the tool needs to be set at dont you, and the quick way to do it?

I was not aware that tipped tools are not advised to be used on hardened materials but HSS steel is better. That's a new one on me ......

 

[addjunkie]

No you need to work tipped tools harder deeper cuts faster feed rates. Most are developed for cnc

 

[Kram]

This might be useful http://mmc-permanent.learnways.com/courses/75/index.html

Carbide is brittle, so most inserts are not sharp. This decides that they want heat, pressure and deep cuts. Instead they have negative rake and cut with pressure, which suits large ridged machines but not so much hobby lathes. Second thing carbide does not like intermittent cuts.

Id like to get some TPGT KC5410 for aluminium, but the cheap CNMT that came with boring bar still gives better finish than my HSS tools.

 

[skotl]

The smaller the diameter the faster your work needs to be turning. That looked far too slow for a good finish. That looked like a tipped tool, if it was they need to be worked much harder. Study up on cutting feeds and speeds, tool sharpening and rake angles etc, well worth spending a bit of time, you tube as good a place as any to start.

Also you do know about the height the tool needs to be set at dont you, and the quick way to do it?

Thanks.
I still need to get to the end of "The Amateur's Lathe" but impatience gets the better of me. I know I'm not applying decent technique here (which, of course, makes it harder to gauge success!).

I thought I understood centering but, now you've mentioned it, I'll go back and review. The video doesn't show a later try at a much higher speed and the results / noise were a lot better there.
Thanks for commenting!

 

[skotl]

Thanks for persevering with me, folks. I clearly have a lot to learn, but at least I know that much!

 

[addjunkie]

If your machine has auto feeds learn how to use them, makes a huge difference.

When i was an apprentice i hated machining, found it tedious and borning. Never really mastered it, probably down to the hangover, it used to be a friday morning, and Ruperts was a big night out on a thursday....

Then when i was at sea a korean crewman taught me some "basic short cuts" nothing speacial just basics really.

When i bought my own machine i was so greatful to him, i had forgotten all the theoretical ********, but hadnt forgotten his tips.

Playing is no good, you need to set your self a project, draw something out and try to make it! Quite rewarding when its finished.

 

[Richiew]

Take some careful measurements before buying a bigger tool post. When I bought my Denham lathe I read somewhere that there isn't a lot of height to play with on these machines. I have a very low slung tool post on mine and it only takes a tiny bit of shimming to get any tool to centre height. Those fancy bigger Chinese quick change tool posts may take you over centre height if they have a thickish base on them.