The Offcial Machinist Thread: Revised 01/04/2014

[jackssmirkingrevenge]

A quickie while I'm at it, delrin piston for DaxSF

[jakethebeast]

Wyz tell me how it works. If its good id like to test one

[wyz2285]

Sure thing, but I don't have a decibel meter or chrony.

[jakethebeast]

Record shot with and without it. Then ill do the smae. We should get a comparison. I mean ill do it with the baffles i have

[wyz2285]

I'll use audacity then, as soon as the parts arrives

[Labtecpower]

I hate school..



I was turning this axle at school, needed to have a h6 tolerance.
Turned it down to 28mm, and measured it. At the tailstock it was .4 mm smaller than at the chuck..
Adjusting the tailstock had no significant effect, after a few adjustments I was still left with a 0.1 mm difference, and a 0.09 mm bulge in the middle.

I've done a lot of work on this lathe, and never had problems with it. I suspect one of my fellow students raped it.. It's a shame to see perfectly good 50-year old lathes being treated this way


On the other hand, they have some nice measuring tools from the USSR

[jackssmirkingrevenge]

*fap fap fap* nice toy you have to play with!

I'll use audacity then, as soon as the parts arrives

Did you get the parts after all?

[Crna Legija]

we don't have the guard on lathes at trade school, we have them at work but most of them have been tweaked slightly!

but we do have the same problem with machine quality, first then the instructor taught us was to check the machine trueness. some of our ones at 5 turns for play in the top slide! getting 3 new ones next year! these bad boys

[jrrdw]

Sloppy live center .0001 out from .0004 standard over 100 or so hours of use... 50 year old lathe, bed warpage. Does the carriage grab a snug spot in it's travel in the length of the bed?

[Labtecpower]

we don't have the guard on lathes at trade school, we have them at work but most of them have been tweaked slightly!

I hate them when working on small workpieces.. But after i've seen some pictures of torn off heads I can appreciate them..

At a company I worked for a while we had lathes with a 75 cm chuck, with the chuck jaws extending 15 cm from the outside..
That one had no guard or whatsoever, imagine getting grabbed by that..

Sloppy live center .0001 out from .0004 standard over 100 or so hours of use... 50 year old lathe, bed warpage. Does the carriage grab a snug spot in it's travel in the length of the bed?

Checked the play on the live center.. max 0,01mm.
The carriage runs smoothly all along the bed.
I'm going to take some measurements next week

[jrrdw]

Checked the play on the live center.. max 0,01mm.
The carriage runs smoothly all along the bed.

May be time to re-polish the gibs. Grime build up (dried oil) can throw off the axes after time.

[wyz2285]

Did you get the parts after all?

Yap, took way more work to install it than I thought through there were two screws inside I didn't knew about, had to sand a slot.
Worked way better than I thought too I noticed the effect right on the first shot.

[jackssmirkingrevenge]

Worked way better than I thought too I noticed the effect right on the first shot.

Excellent, glad to hear it see, monocores rule!

Did you do a comparison video? And does it still shoot well?

[wyz2285]

Did you do a comparison video?

That's a problem, I don't have any video of it without the internal and now it's stuck there I can't remove it

[jackssmirkingrevenge]

Oh well, as long as it's better now