Conundrum.......... If the whole world had to go to metric sizes, how come ALL metric sockets use 1/4, 3/8, and 1/2 inch ratchets/breaker bars?

Think about it..............

 

For the guy working without metric wrenches..............
3/8"= 10mm
7/16"=12mm
1/2"= 13mm
9/16"=14mm
3/4"=19mm
They may fit a little tight or loose, but it works.

Metric bolts come in coarse, fine and extra-fine thread pitch, so know what you need before you grab that box of "M10x 40mm" bolts.

 

Aah - you may get in some tight fixes working with that. 1/2" is close - but other sockets will bind. Best idea is to GET metric if you are WORKING with metric.

Damn I hope I haven't run a good source of info off by being an arrogant prick (I'm not, really) but metric seems so weird at times to those of us used to the "OTHER" standard.

So what we have so far is that "M10" is a ten millimeter wide shaft bolt. The SHAFT - not the head, the round part that goes down into the hole.

The thread gauge is very different, in that you are not counting the threads over a space that is known.

That right there is outstanding attention to detail - and I can't thank you enough! That was beautifully written....

But an honest to God metric thread gauge would be the answer to all problems, and the one(s) I have are all "other..." which tends to render them useless for this.


What do you use on a daily basis to deal with metric threads and bolt sizes? That info would be enormously helpful until we all (or some of us anyway) just have a lot of metrics sorted to different parts bins and get used to it?


I mean, when I went online looking, I got confused easily because I really had no idea. I was making my best guess on what I knew of SAE bolts and expected metric was a lot like it. It probably is, but what I would like to "FINE DOWN" is the conventions we need to know that are a little bit different.

The "LENGTH" of bolt is pretty simple. It is the depth under the head (of whatever design or pattern) to the end of it.

I feel that we need to bear down on the "THREAD DESCRIPTION" so that it is well understood.

Unlike SAE which counts so many threads over a one inch distance, what LC_53 is saying is that in Metric it is a precise measure of the distance between threads, given in mm


Have I got that right?

If that is true, Metric threads are a very strange animal to our own understanding - but not so hard to figure out.


~Wolfie


PS: I still have no idea what metric bolts to order in a 2 1/2 inch length to put my old Ranger engine on a stand. But I know it's an M10 and it looks oddly like a medium thread.

~Well crap...



CHEERS FOR EVERYBODY!

Let's keep the discussion going on...

PS: On socket set drives
Consider what Robert A. Heinlein once said:
"Why reinvent what you can purchase down the street?"

~It's like lycra panty hose - one size fits all

 

Curiouser still -

I wonder if our friends 'Down Under' consider a 3/8ths drive a ten , a half inch drive a thirteen drive, and a 3/4 inch drive a nineteen drive?

Quite what a quarter drive works out to I have no idea... Probably a 6, or somewhere around there.

 

If I may be so bold; I'll recommend that everyone should have at-least read this book

 

Holy batcrap, Batman - that's going on my wish list at Amazon!

Thank YOU!!! I bet it's priceless information.

* I love it when new resources become available...


The more I know, and the more I understand - the better and bitchener toys I can create!

Eddie Murphy once told his teachers that he wanted to be a "TINKER" when he grew up, and in a way he is: He tinkers with how we see everything, using COMEDY as a vehicle to do that.

What I always wanted to be was a wonderful toymaker. But my definition of "TOY" may be a lot different from what normal people think of as 'toys'...

 

Dutch, understand that LC has a 35 year head start on you and you are starting to get a bit long in the tooth yourself, so you ain't gonna get it all at once. Kinda like enjoying that 12 pack at the 1st of the month... sometimes you can absorb it better when take it in slow and easy.

.

 

**BOOK sent for!

Oh and BTW (I went to Fastenal this morning)
M10 -1.50 x 40mm is the original bell housing bolt. (About an inch and a half)

For engine stands with 2 inch spacers, M10 -1.50 x 60mm is a two and a half inch long bolt that fits perfect.

For the NON-threaded holes you need M10-1.50 X 90mm, which is a three and a half inch length that will also need a matching M10 -1.50 nut

All the ones I got from Fastenal were grade 5.

~Thing about Fastenal is - they are geared to higher end users, and only sell by the bag full. I got ten 7/16ths -14 x 2 1/2" bolts to hang a Windsor on one stand, and twenty M10 -1.50 x 60's for the 2.3L

And I STILL had to send for some M10 -1.50 x 90mm's on Amazon, along with a bag of matching nuts.
The good news is they'll get here on Friday



But still, getting back to the original theme, the better we understand the fasteners we use - the better we can build


I suppose next we should talk about "TENSILE STRENGTH"

Or what can the bolt hold?

I kinda hope FABMAN gets involved here, there are differences between flexibility, hardness, brittleness, and ultimate strength due to various materials. Not to mention the ability of different materials to resist corrosion. For me, Stainless Steel is just about the icon of materials to use.

It comes in three levels of strength, and it's metallurgical makeup is interesting.

Stainless is found in high end kitchen tools, and surgical equipment, because of it's relative incorruptibility. It just don't RUST...

But it is also very high strength

The only downside is that short of TITANIUM, this may well be the most expensive metal you can have rod bolts and the like made from.

Some of the other considerations are: For WHAT YOU INTEND TO BUILD, what is the wisest choice of materials to use?

How deep are your pockets?

Are you building (a thing) to push the edge of the envelope, or to last as long as possible?

All of these ideas mix together to form the final choice, don't they?

The questions I see for right now are:
What is 20/20 cold rolled steel good for?
What is Grade FIVE
What is GRADE EIGHT?

Are there more grades above that? And what is the cost/benefit of using them?

There seems to be a trade-off between strength and relative brittleness that needs exploring

 

We refer to Grade 2 Bolts as Butter Bolts.

Grade 8 is used in Heavy equipment, etc.

https://www.boltdepot.com/fastener-information/materials-and-grades/bolt-grade-chart.aspx

 

Be careful using stainless bolts, most hardware stainless bolts are low grade. Most are only slightly better than grade 2. And galling is a big problem if anti-seize is not used.

 

Not sure that there is a 20/20 cold rolled steel unless it would be M2020 Cold Rolled Steel which is a mild cold rolled steel product offered by a Nissan mill. Most Cold Roll Steel Products numbered classifications denote their chemical composition and / or harness. Like C1018. Same with Stainless Steels. Although, IMPO, all metals from China should be noted as such as they do not seem to measure up.

Good luck on finding any real info on 20/20 CRS as I am not finding any reliable info on that one.

.

 

How does cast iron rate in terms of tensile strength? It seems like some grades of bolt are weaker than cast iron - and would break before stripping out the threads in a block (for example)

I know that for most aircraft/airframes 70/75 T-6 is used, which is a very high heat treatment level. The malleability of the metal is traded off for hardness, if you try to bend a 7075 T-6 sheet, it will usually crack right along the bend line.

 

In a pinch you can use grade 5 for automotive but NEVER grade 2..............In metric try to stay with 10.9 bolts over 8.8 bolts.

 

10.9 being stronger than 8.8? What's the measure and scale? I know grade two is junk...

It seems to me grade five is a common factory head bolt

Grade eight or higher is what you want for a rod or main, and the weakest link in a Ford engine is the rod bolts

When they bust - everything goes to flinders

Q: What is the strongest rod bolt you can use, that won't cost you a new mortgage?

 

The one that is strong enough to not fail in the application is is screwed in to...