Measuring 400 Day Clock Suspension Springs

[gary G]

Hello:
I have a group of Horolovar unmarked/untagged suspension springs. I would appreciate any comments, suggestions or advice as to the best way to measure these. Length is obvious of course, and the book is great. Thickness and width? Is what I am speaking of.

Many Thanks,
Gary G

 

[gary G]

Hello:
I have a group of Horolovar unmarked/untagged suspension springs. I would appreciate any comments, suggestions or advice as to the best way to measure these. Length is obvious of course, and the book is great. Thickness and width? Is what I am speaking of.

Many Thanks,
Gary G

 

[gvasale]

a good reliable micrometer that reads to .0001" will set you back about $100.00. These use a vernier scale on the barrel to read the .0001" An indicating micrometer will cost a bunch more. A micrometer like the Starret 221 uses a spring loaded thimble and a much wider .0001 scale will let you divide the .0001" in half and with practice less, runs in the $300.00 range. There are lots of micrometers on EBAY, and it gets to be just how accurate do you want to be. It may be less of a headache to order the size you want, (hopefully) it will be correct.

 

[Andy Krietzer]

Hi Gary,
Get a micrometer and measure the thickness. If they are Horolovar brand suspension spring material, then that is what is used for the measurements listed in the Horolovar guide. Don't worry about the width. The guide shows you the length for each known suspension unit.

If they aren't Horolovar brand springs, they won't have the same properties as the ones listed in the guide, different material and width. Comparing apples and oranges.

gvasale, We posted at the same time. I think you can get a usable new micrometer for about $30 or less.

Andy

 

[gvasale]

You're right. From China. I know there are lots of people who do buy Chinese, but if it's off, where's the value then? At least with known quality tools, you have accurate measurments.

 

[harold bain]

I found my micrometers at an auction for $5.00 each, 1 in metric and one in English :biggrin: :biggrin:. Although they are used, I don't think this is a tool that would wear out. Don't underestimate Chinese tools, many are of decent quality now. Harold

 

[gvasale]

Harold I agree somewhat. The thing is, micrometers do wear out. I worked for a large machine tool manufacturer in the middle 70's. The did calibrations on the tools. They would check the accuracy over the whole range of the tool and report its errors. now, say you know its reading .0003" small at .003", you can compensate to a degree, but remember these suspension springs are often supplied with some significant figures on the .0001" range. Everyone has to make their own choices of course, but the question was asked. Would I think that I could always do the best job with tools of unknown qualities? Not always. Depends on what you do. Where I work, I've seen stuff rejected for being off .0005. And by the way, I've worn out two high quality dial calipers already.

 

[John Hubby]

I've had the problem of spilling a bunch of mixed size springs on the floor, and then had to sort them back to the correct size holder.

This can be done easily with a good micrometer. If in inches, it MUST read to 0.0001" with interpolation to the 5th decimal, if metric to 0.001 MM with interpolation to the 4th decimal. I also agree that there can be NO "sloppiness" in the measurement. Remember you are trying to differentiate the springs by a difference of only 0.0001".

Horolovar springs are all the same very accurate width so you don't have to measure that. They achieve that using a patented rolling process that produces exactly the same width for each size spring, and also gives the springs rounded edges that are much more resistant to breakage than springs made with a slitting process (the "other" springs).

John Hubby

 

[jvbram]

Horolovar don't mention the width. Is that because all the springs have the same width? I measured one at about 0.6mm.