Search found 1399 matches

by John Hasler
Thu Apr 02, 2020 8:28 am
Forum: General Discussion
Topic: Potting electrical coil in steel
Replies: 21
Views: 1286

Re: Potting electrical coil in steel

I have a turns counter around here somewhere that I've never used. If you want I can try to find it and send it to you. I like Bill's idea better, though. You'll know how many turns per layer you have so let the machine count layers. Note that the wire gauge refers to the bare wire while the diamete...
by John Hasler
Wed Apr 01, 2020 7:52 pm
Forum: Milling Machines
Topic: High frequency vibration on Y axis
Replies: 16
Views: 307

Re: High frequency vibration on Y axis

The source of the excitation is the cutter. There's nothing wrong with it: it's just that a tooth biting into the part 110 times per second inevitably causes vibration. This happens to be a resonant frequency of Ron's leadscrew when it's sticking out about 10".
by John Hasler
Wed Apr 01, 2020 5:42 pm
Forum: General Discussion
Topic: Potting electrical coil in steel
Replies: 21
Views: 1286

Re: Potting electrical coil in steel

I suggest looking for magnet wire with a high temperature rating rather than a high voltage rating. At 24V voltage breakdown is not going to be the limiting factor. Also make sure the wire insulation is compatible with the potting compound. I don't think the spray is a good idea. It could interfere ...
by John Hasler
Wed Apr 01, 2020 8:07 am
Forum: Milling Machines
Topic: High frequency vibration on Y axis
Replies: 16
Views: 307

Re: High frequency vibration on Y axis

I asked about the dimensions because I can calculate the length at which the screw will resonate at the tooth rate you get at 3300 rpm. The resonant frequency is inversely proportional to the square of the overhanging length. I get roughly 10" as the resonant length for 3300 rpm and a two flute cutt...
by John Hasler
Tue Mar 31, 2020 7:49 am
Forum: Milling Machines
Topic: High frequency vibration on Y axis
Replies: 16
Views: 307

Re: High frequency vibration on Y axis

spro's got it. Is there any change in the sound of the mill when this happens or even just at that speed? The fact that it affects only the Y axis at one spot while cranking in one direction leads me to suspect that the Y axis screw itself is vibrating. What are the dimensions of that screw? Does it...
by John Hasler
Mon Mar 30, 2020 10:11 am
Forum: Milling Machines
Topic: High frequency vibration on Y axis
Replies: 16
Views: 307

Re: High frequency vibration on Y axis

These

- With or without the endmill cutting, so even when just cranking the handle.
- Only during a specific operation using a 3/16" endmill to cut a slot.

seem contradictory. Explain?
by John Hasler
Sat Mar 28, 2020 10:45 pm
Forum: Milling Machines
Topic: Uneven cut
Replies: 8
Views: 333

Re: Uneven cut

Check all the gibs. A loose one can do that because of the cyclic force you apply to the table as you crank.

Did you have the x axis locked?
by John Hasler
Tue Mar 24, 2020 1:54 pm
Forum: General Discussion
Topic: New lathe with questions
Replies: 5
Views: 512

Re: New lathe with questions

Harold would add a leadscrew and power feed, surely.
by John Hasler
Wed Mar 18, 2020 2:30 pm
Forum: The Junk Drawer
Topic: OP even for the Junk Drawer - Corona virus
Replies: 40
Views: 1630

Re: OP even for the Junk Drawer - Corona virus

This is true, but it is not necessary that everyone be infected. As the fraction of the population that has had the disease and is now immune increases it becomes harder and harder for the disease to spread. This is because members of the set of vulnerable individuals become less and less likely to ...
by John Hasler
Mon Mar 16, 2020 3:36 pm
Forum: General Discussion
Topic: Eye bolt rating
Replies: 23
Views: 1545

Re: Eye bolt rating

Weld those eyebolts closed, don't lift overhead, and you'll be fine.
by John Hasler
Thu Mar 12, 2020 7:22 am
Forum: Live Steam
Topic: Propane burner igniters
Replies: 10
Views: 1036

Re: Propane burner igniters

I installed one of these:

https://www.ebay.com/itm/1PCS-DC-3v-6v- ... SwrtFbYBP5

on the propane-fired water heater at our camp up north. It's been working well for several years now.
by John Hasler
Sun Mar 08, 2020 7:16 pm
Forum: The Junk Drawer
Topic: Repairs
Replies: 9
Views: 836

Re: Repairs

My tractor is 35 years old; good. Boat motors, one is 50 years old the other 35. Good. Car 21 years old, packed with processors + electronic controls. Not so good. I've been in a JD shop where the repair team [yes, team] was gathered around a laptop connected to the tractor. Nuts. But everyone says...