Packard Forum Index » General

If you'd like to create a tool kit for your Packard or other vehicles, I came across this listing of metric and standard interchanges so as not to have to carry a bazillion wrenches around. Also helpful in the garage if you're metric impaired like me




Metric/Standard interchanges
5/16 & 8mm Apex
7/16 & 11mm
1/2 & 13mm
9/16 & 14mm
5/8 & 16mm
3/4 & 19mm
7/8 & 22mm
13/16 & 21mm rare
15/16 & 24mm
1 1/16 & 27mm
1 1/4 & 32mm

Quote:

Rich , don't know how about in your part of the world by 21mm isn't rare in my neck of the woods as this is the usual size for a spark plug wrench for many European cars. Well, quite a few number of people use a 22mm wrench but that's another story...







[picture source: www.atu.de]

I wouldn't agree that they interchange at all, unless you are talking about " finger tight" nuts or bolts. Be prepared for lots of rounded shoulders using a 13mm on 1/2 inch nuts/bolts, and the rest for that matter. There is a product called Metrinch which fits inch and metric, claiming to drive on the shoulders of the nut/bolt. They do interchange but have some play when operating. PT

Neither I would agree that metric and inch tools are interchangable at all, as long as you do not want to have rounded shoulders/destroyed nuts and bolts.

Tom

Thanks for the helpful chart Rich. Of course, some Metric 'substitutes' will be a closer fit on an Imperial nut than others!
Down here we have had 'metrification' foisted upon us many years ago, so most of us have two sets of tools, usually including the 'UN' set of spanners Dad used way back when (- most still in working order and ready for use on the Packard). But occasionally I still reach for a spanner, judge it using the 'quick glance' method, and try it on a nut or bolt. Sometimes it is a good close fit, but if not I don't use it.

Years ago, when metric fasteners were first being used on a large scale in the U.S., I bought a set of inserts for 6-point socket wrenches that would convert an inch socket to a metric. Never used them so can't say how good they fit. I'll see if I can find them and post a photo.

(o[]o)

You can always stop by Harbor Freight and get a combination wrench set for $8 and a socket set for $10

I've started work on my youngest son's '61 Jaguar Mk2 3.8 sedan MOD. I was having some problems figuring out if I needed SAE or Metric wrenches. I soon learned there are other standards to consider. But you can see that not many really match up.

baconsdozen.co.uk/tools/conversion%20charts.htm

Attach file:

---

  (30.48 KB)

Quote:

Joe, please take into consideration that a 1961 Jaguar has been built a decade before UK decided to go the metric way (1973).


side note
The changeover phase in UK, contemplated in article 1 of the a.m. decision, streched the time of parallel running of both systems until 2010. In 2007 the timeframe was extended ... without limitation.


to depart from the beaten track



[picture source: www.mz-web.de]

The 113mm and 1/2" are almost perfectly interchangeble. A good fit. As 25.4mm = 1" you can calculate the difference easily. So 1/2" x 25.4mm is 12.7mm. So the fit is within 0.3mm which is about a 2.4% ((13-12.7)/13 x 100) a small difference. This so small that there should be no rounding. For 9/16 =?14 mm: 9/16 x 25.4 = 14.29 which is 2.1%, a small difference also
Incidentely, the 25.4mm = 1" is not approximate but is an exact relationship.
So you can calculate the rest of the numbers and add this information to the original tabulation. Make a copy and post it on your shop wall or put it in your toolbox.
Humer