Search found 355 matches

by mklotz
Sat Aug 08, 2020 10:05 am
Forum: Milling Machines
Topic: Reading deg min and seconds
Replies: 16
Views: 398

Re: Reading deg min and seconds

Here's another way to get a feel for such a small number... Let's say you have an RT with a 90:1 ratio and a crank on the input shaft that has a 1.5" radius. How far must the end of the crank move to rotate the table by one arcsecond ? 4.85E-6 * 90 * 1.5" = 0.00065" or less than a thousandth of an i...
by mklotz
Fri Aug 07, 2020 5:16 pm
Forum: Milling Machines
Topic: Reading deg min and seconds
Replies: 16
Views: 398

Re: Reading deg min and seconds

I find it hard to believe that you need to be concerned with that sort of accuracy. An arcsecond is 4.85 microradians. At a distance of 100 yards that's an offset of only 0.017 inches. Round off the arcseconds to the nearest arcminute and go with that.
by mklotz
Tue Jul 21, 2020 5:40 pm
Forum: General Discussion
Topic: Split Cotters
Replies: 9
Views: 537

Re: Split Cotters

liveaboard wrote:
Tue Jul 21, 2020 5:26 pm
I'm having trouble picturing this; can someone maybe post a picture?
https://www.youtube.com/watch?v=DdHd0kJ2_3c

The description of the device starts right around 3:00 into the video.
by mklotz
Fri Oct 11, 2019 11:07 am
Forum: Lathes
Topic: Screwcutting not picking up in the same place
Replies: 19
Views: 7082

Re: Screwcutting not picking up in the same place

charkmandler wrote:
Fri Oct 11, 2019 10:12 am
... I will look in to needing different gears for different metric thread pitches.
If you have a 3 mm leadscrew, this chart may be of help...

http://bbs.homeshopmachinist.net/thread ... ost1258773
by mklotz
Sun Aug 25, 2019 9:08 am
Forum: General Discussion
Topic: Looking to build a dividing head
Replies: 6
Views: 2261

Re: Looking to build a dividing head

The hole circles you need on the plates are a function of the dividing head's internal gear ratio. When I wrote the programs available under the DIVHEAD archive on my webpage, I included a program, DPLATES, which can be used to determine which hole circles are required to perform all divisions up to...
by mklotz
Fri Aug 16, 2019 4:36 pm
Forum: Live Steam
Topic: Wood lagging on the Invicta
Replies: 10
Views: 3574

Re: Wood legging on the Invicta

Legging? Isn't the proper term lagging? No, I'm not trying to be the "word cop". Just hoping to either verify the proper term, or prevent the use of improper terms. It's better for all concerned. So then, those who know, please speak up. :wink: According to the dictionary... Legging - a covering fo...
by mklotz
Sun Jul 28, 2019 12:57 pm
Forum: General Discussion
Topic: Winding springs
Replies: 7
Views: 2559

Re: Winding springs

I tried winding a spring using .020 piano wire around a 1/4" mandrel (Sexist term in Ca.). After unwinding, the coil was 1/2" diameter. I wanted 3/8" diameter and a bit stiffer spring. I'm guessing .030 wire would be better, but I don't know what diameter of mandrel to use. The free coil length wil...
by mklotz
Thu Jul 04, 2019 8:56 am
Forum: Live Steam
Topic: 1859 locomotive
Replies: 4
Views: 2515

Re: 1859 locomotive

Glenn,

Could you please give me the Wikipedia URL so I can pass that information along to the folks at HMT where I saw this picture?
by mklotz
Tue Jul 02, 2019 9:26 am
Forum: Live Steam
Topic: 1859 locomotive
Replies: 4
Views: 2515

1859 locomotive

I'm not a railroad afficionado (though I have built some live steam stationary engines) but I saw this photo on another forum and thought you folks might enjoy seeing it... https://s3-us-west-1.amazonaws.com/hmt-forum/egyptian_viceroy_steam_locomotive.jpg Full size image here... https://s3-us-west-1...
by mklotz
Tue May 14, 2019 12:23 pm
Forum: General Discussion
Topic: Hyperboloid of revolution twirler
Replies: 11
Views: 3315

Re: Hyperboloid of revolution twirler

The Cartesian equation of a hyperboloid is: (x^2 + y^2)/a^2 - z^2/b^2 = 1 With the origin set at the center of the figure, define the x direction to be left/right and the z direction up/down. The y direction is then perpendicular to the board. To obtain the equation of the cuts in the board, take y ...
by mklotz
Wed May 01, 2019 8:56 am
Forum: The Junk Drawer
Topic: Today's Discovery: Wire Gauge Drill Bits for Carbs
Replies: 16
Views: 7951

Re: Today's Discovery: Wire Gauge Drill Bits for Carbs

The one thing I wish I had is an index. I have to use calipers to figure out which drill bit is which. Huot sells an index... https://www.amazon.com/Huot-10400-Drill-Index-Gauge/dp/B00018A1Y6/ref=sr_1_4?crid=2NV175XHLM44K&keywords=drill+index+61-80&qid=1556718605&s=gateway&sprefix=61+80+drill+index...
by mklotz
Wed Apr 10, 2019 3:59 pm
Forum: General Discussion
Topic: Measuring a diameter without a caliper
Replies: 19
Views: 6080

Re: Measuring a diameter without a caliper

Sorry, wrong link https://sciencing.com/radius-circle-chord-5929711.html Or you could just give him the formula r = (c^2 + 4 * s^2)/(8*s) where: c= chord length s = sagitta (perpendicular distance from chord to circumference) = jaw length from tip to inner surface of caliper beam r = radius of circ...