Search found 103 matches

by roundnose
Tue Jun 01, 2021 12:31 pm
Forum: Site Software Questions and Answers
Topic: Thoughts on private messages
Replies: 47
Views: 1032800

Re: Thoughts on private messages

Hopefully no one has the bad experience I have had picking up a troll that has attempted to damage my business, by stalking me and contacting people I am involved with, and well, saying not nice things. I will apologize, for not accepting any private messages on any forum regarding any subject, on s...
by roundnose
Tue Jun 01, 2021 8:56 am
Forum: Lathes
Topic: They said go big!
Replies: 48
Views: 42533

Re: They said go big!

Those old CJ lathes are just great! They were used at gov facilities close to me, a friend managed to get one, and has been happy with it, finds it easy to use.
The one in the photos here, has a longer bed then the few I have seen.
by roundnose
Tue Jun 01, 2021 2:41 am
Forum: General Discussion
Topic: Single Point Threading 101
Replies: 43
Views: 22240

Re: Single Point Threading 101

I do a somewhat specialized threading where as the requirement generally forbids using relief grooves, the threads pitch is usually 12 tpi v threads, but also modified buttress, on occasion. The other requirement is the nut must go on without bind, with no perceivable shake. It must be done quickly ...
by roundnose
Tue Jun 01, 2021 1:19 am
Forum: General Discussion
Topic: Suggestion to secure a crankcase for fly cutting
Replies: 30
Views: 11390

Re: Suggestion to secure a crankcase for fly cutting

I have not been around for a very long time, and happened to see this thread. This is something that I have done a lot of commercially. The most important thing, the cylinder surface must be in plane with the center of the crank shaft. How I tested that was to machine a shaft, and whatever bushings ...
by roundnose
Tue May 07, 2013 10:27 pm
Forum: General Discussion
Topic: Some info on high accuracy machining
Replies: 3
Views: 2791

Re: Some info on high accuracy machining

Perhaps, I was not clear enough. So, with a jigborer or toolroom lathe using those methods under those ideal conditions, one possibly could hit 79 millonths of a target size. That said, under less then ideal conditions, and perhaps worn, or otherwise lesser machines, one could hit- say 4X that, ever...
by roundnose
Tue May 07, 2013 12:48 am
Forum: General Discussion
Topic: Some info on high accuracy machining
Replies: 3
Views: 2791

Some info on high accuracy machining

This is sure to PO some but, it does exist. This is really old hat, but the methods being printed out is really not common. Often touted as not possible, cant be measured, but in reality has been done for decades by the most skilled craftmen. I have had these boring heads for around 20yrs, using the...
by roundnose
Mon May 06, 2013 9:55 pm
Forum: General Discussion
Topic: self-sharpening setup for wood planer
Replies: 20
Views: 8615

Re: self-sharpening setup for wood planer

Unfortunately cutter heads are not easy to remove from planers. A few months ago I found a Powermatic 160 16" planer, vintage 1959, near mint condition from a Montana school. The machine had the Esta dispozAblade system installed, but never used, with a dozen extra blades. A grinder set up is a...
by roundnose
Mon Apr 01, 2013 12:40 am
Forum: Lathes
Topic: wobble in lathe
Replies: 15
Views: 7894

Re: wobble in lathe

I suppose slots can become too worn, I just have not come across it. Though, some chucks are looser in the jaw slots then others, rotating the work when clamping seems to make that not a problem. This chuck, a Buck 6"-6jaw is one of the most worn I have came across. A Hanford surplus, removed f...
by roundnose
Sat Mar 30, 2013 10:59 pm
Forum: Lathes
Topic: wobble in lathe
Replies: 15
Views: 7894

Re: wobble in lathe

In 4 decades, and rebuilding dozens of scroll chucks, just never seen worn out jaw slots, or worn out scrolls. Even on chucks used on grinders. Some chucks do have looser slots then others however. I read that all the time from people that have never rebuilt chucks. Two bad things happen from wear, ...
by roundnose
Fri Mar 29, 2013 10:48 pm
Forum: Lathes
Topic: wobble in lathe
Replies: 15
Views: 7894

Re: wobble in lathe

Google "grinding lathe chuck jaws" there are some videos about, good for the basic idea. This is one of the very odd things many machinist have a mental block over. There are better ways to load the jaws that seem to be shown on the videos. Who knows, maybe you might want to rebuild scroll...
by roundnose
Wed Mar 27, 2013 10:47 pm
Forum: Lathes
Topic: Who uses tool post grinders?
Replies: 10
Views: 6018

Re: Who uses tool post grinders?

Soft jaws, very handy on scroll chucks. I was refering to close tolerance work with 4jaw chucks, Where as the chuck jaws ground in place on the machine for full work contact, and once clamped and trued, the work piece also running true at distance from the jaws. This eliminates using soft pads on th...
by roundnose
Wed Mar 27, 2013 1:32 pm
Forum: Lathes
Topic: Who uses tool post grinders?
Replies: 10
Views: 6018

Re: Who uses tool post grinders?

A needed evil to get the most out out of a Monarch 10EE lathe. This is why, the best results using "jaw chucks" is with 4jaw chucks. The chuck must hold a test bar at least 8" out from the jaws true. Otherwise, there will be bind with the tail center "unless the part was center d...