Search found 814 matches

by Jerry Biehler
Fri Apr 20, 2018 1:13 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: My Gamma Spectroscopy Setup
Replies: 5
Views: 377

Re: My Gamma Spectroscopy Setup

LN2 is not that bad. I use it for my EDX, I have a 25L dewar and it costs less than $20 to fill and if I am not using it lasts several weeks. I had a 50L and that thing would keep for quite a long time.
by Jerry Biehler
Wed Apr 18, 2018 3:26 am
Forum: Vacuum Technology (& FAQs)
Topic: Vacuum pump rebuild
Replies: 30
Views: 1428

Re: Vacuum pump rebuild

Yep, unbolt the pump and check the rotor and stator. If there is ANY pitting the pump is scrap. That probably should have been the first thing that was done.
by Jerry Biehler
Wed Apr 18, 2018 3:18 am
Forum: Vacuum Technology (& FAQs)
Topic: Can I make my own ConFlat flanges?
Replies: 27
Views: 671

Re: Can I make my own ConFlat flanges?

Better pic with less glare:

ImageIMGP4948 by Jerry Biehler, on Flickr
by Jerry Biehler
Wed Apr 18, 2018 3:11 am
Forum: Vacuum Technology (& FAQs)
Topic: Can I make my own ConFlat flanges?
Replies: 27
Views: 671

Re: Can I make my own ConFlat flanges?

Yes, you can. You dont need a CNC machine. And CNC is much more complex than throwing a CAD file at a machine and make it go.

I made this adapter years and years ago, manually machined:

ImageIMGP4940 by Jerry Biehler, on Flickr
by Jerry Biehler
Wed Apr 11, 2018 5:48 am
Forum: Vacuum Technology (& FAQs)
Topic: Vacuum pump rebuild
Replies: 30
Views: 1428

Re: Vacuum pump rebuild

Other than megging it and current the rest of the tests are not important. Put it together and get it working.
by Jerry Biehler
Tue Apr 10, 2018 2:52 am
Forum: Vacuum Technology (& FAQs)
Topic: TMH-260 Turbo
Replies: 14
Views: 845

Re: TMH-260 Turbo

A lot of pfeiffers are two phase. You will have pins for that, an eeprom, and a temp sensor. I am not sure if they have halls.
by Jerry Biehler
Sat Apr 07, 2018 6:11 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Progress... or lack thereof
Replies: 6
Views: 650

Re: Progress... or lack thereof

I didn't even know mitsubishi made turbos. Huh...

Sell em' to pay for other stuff would be my plan.
by Jerry Biehler
Thu Apr 05, 2018 7:21 am
Forum: Vacuum Technology (& FAQs)
Topic: TMH-260 Turbo
Replies: 14
Views: 845

Re: TMH-260 Turbo

I hope there is more of it than just that...
by Jerry Biehler
Tue Apr 03, 2018 4:26 am
Forum: Vacuum Technology (& FAQs)
Topic: Vacuum pump rebuild
Replies: 30
Views: 1428

Re: Vacuum pump rebuild

It's usually a good idea to put a megger on the windings to check for leakage after a motor has been in that state.

This is also a good use for electrolytic rust removal. I dont like using acids no matter how benign around stuff like this.
by Jerry Biehler
Tue Apr 03, 2018 12:59 am
Forum: Vacuum Technology (& FAQs)
Topic: NT150/360 Problem
Replies: 8
Views: 583

Re: NT150/360 Problem

You wait. Pumps can be restarted it will apply a bit of power and look at the back emf and determine the speed and start ramping up from there. Waiting a few minutes is better than letting in too much air and turning your pump into a bunch of shredded aluminum foil. It's also hell on the bearings. I...