Metric Rivnuts - Drill Bit Size?

[TipsyMcStagger]

This is my first time using rivnuts. I bought this metric set on Amazon. It came with no drill bit chart.

I need to set a few of the M6 rivnuts. I decided I'd better try to set one in scrap and it's a good thing I did. I drilled a 23/64" hole and the knurling on the rivnut would not bite. I tried another hole 11/32" and could not get the rivnut through the hole.

I suppose the obvious solution is to buy a set of metric drill bits? I would have though I could get "close enough" with SAE bits, but seemingly not.

Thoughts? Tips?

Tipsy

 

[rlitman]

The few metric rivnuts I've used, all had stated weird metric drill sizes that actually work out to SAE drill diameters. For example, the M4 rivnuts I have on my desk require a 6.35mm hole. That's .250" for those who don't feel like doing the conversion in their heads.

Get the spec sheet on your rivnuts before you go wasting money on metric drill bits.

Oh, and my guess is your problem is with the thickness of the scrap. Rivnuts come rated for different thickness ranges, and yours may not be good for what you tried it in.

edit: The charts I am seeing show a 3/8" diameter hole for many 6mm metric rivnuts. Others call for 9mm. So if you're not grabbing with a 23/64" hole, maybe you're using the rivnut in something outside of it's grip range.

Do you have a T sized drill bit? That's a thousandth smaller than 23/64. S is over 4 thou larger than 11/32.

 

[Astro_Pneumatic_Tools]

We're currently in the manufacturing stage of a tool just for this, single bit that does SAE and Metric Rivnuts for 22-30 different sizes and brands of rivet nuts.

Also, it comes with a magnetic chart

 

[TipsyMcStagger]

Get the spec sheet on your rivnuts before you go wasting money on metric drill bits.

If I could, I would. I don't see one available to download.

If 23/64" is too big and 11/32" is too small, I'm not too sure what good a chart is going to do. I don't have a drill bit that's between the two sizes I already tried.

Oh, and my guess is your problem is with the thickness of the scrap. Rivnuts come rated for different thickness ranges, and yours may not be good for what you tried it in.

The scrap is actually thicker than the metal I need to set the rivnuts in (car firewall). So I would think it would only be worse on the car.

Tipsy

 

[rlitman]

...If 23/64" is too big and 11/32" is too small, I'm not too sure what good a chart is going to do. I don't have a drill bit that's between the two sizes I already tried...

See my edit: S and T are between those two sizes.
Another option would be to use a tapered reamer to adjust the hole size.

...The scrap is actually thicker than the metal I need to set the rivnuts in (car firewall). So I would think it would only be worse on the car...

Well, that's definitely an application where I'd want some good practice results before causing damage.

Worst case, you can always use a nut plate like this:
https://www.pegasusautoracing.com/productdetails.asp?RecID=24927

 

[rlitman]

We're currently in the manufacturing stage of a tool just for this, single bit that does SAE and Metric Rivnuts for 22-30 different sizes and brands of rivet nuts.

Also, it comes with a magnetic chart

What, like a step drill with rivnut sized steps? Wow, that would make a great companion for your new rivnut tool.

 

[TipsyMcStagger]

edit: The charts I am seeing show a 3/8" diameter hole for many 6mm metric rivnuts. Others call for 9mm. So if you're not grabbing with a 23/64" hole, maybe you're using the rivnut in something outside of it's grip range.

Do you have a T sized drill bit? That's a thousandth smaller than 23/64. S is over 4 thou larger than 11/32.

See my edit: S and T are between those two sizes.
Another option would be to use a tapered reamer to adjust the hole size.



Well, that's definitely an application where I'd want some good practice results before causing damage.

Worst case, you can always use a nut plate like this:
https://www.pegasusautoracing.com/productdetails.asp?RecID=24927

I don't have S and T drill bits. I just gave it another go by "overdrilling" with the 11/32" bit. I had to drive it in with a block of wood but it worked.

I need to practice a few more times because I stripped the rivnut by over-tightening with the installation tool. And probably also because these rivnuts are not very high quality, I'm guessing.

I don't have any access behind the firewall, so I can't use nut-plates.

Thanks for the continued input.

Tipsy

 

[rlitman]

Ok, so it sounds like yours are the type that require a 9mm hole.

S is just under 9mm (but is larger than 11/32"), T is just over (but is smaller than 23/64"):
http://www.gearhob.com/eng/design/drill_eng.htm

You can probably pick up individual letter sized drill bits at the local independent hardware store for a crazy price (half a dozen bits will usually pay for a full set).

In sheet metal, step drills give you much rounder holes than regular twist drills. Something like this might help you out:

https://www.amazon.com/dp/B01MYXGO5V/?tag=atomicindus08-20

 

[Astro_Pneumatic_Tools]

What, like a step drill with rivnut sized steps? Wow, that would make a great companion for your new rivnut tool.

And chamfered step angles that allow the tool to remove set rivet nuts too by shaving the material on the ID until it's gone

 

[TipsyMcStagger]

Ok, so it sounds like yours are the type that require a 9mm hole.

S is just under 9mm (but is larger than 11/32"), T is just over (but is smaller than 23/64"):
http://www.gearhob.com/eng/design/drill_eng.htm

You can probably pick up individual letter sized drill bits at the local independent hardware store for a crazy price (half a dozen bits will usually pay for a full set).

In sheet metal, step drills give you much rounder holes than regular twist drills. Something like this might help you out:

https://www.amazon.com/dp/B01MYXGO5V/?tag=atomicindus08-20

Good info. Thanks. I honestly was unfamiliar with lettered drill bit sizes. I'm not sure if I'll be able to find any in this area but I'll have a look.

Tipsy

 

[nes999]

Good info. Thanks. I honestly was unfamiliar with lettered drill bit sizes. I'm not sure if I'll be able to find any in this area but I'll have a look.

Tipsy

I buy my from my local industrial supplier. If all else fails Grainger and fastenal tend to stock them.

Sent from my VS988 using Tapatalk

 

[cherrybomb]

Before you spend your money or mess up the project,that asking advice and trial and error is a good thing.Whether its metric,number or letter drill you probably will end up at a speciality drill sales.It will cost more,most definitely, but if you buy just one bit and get a good job thats o.k.Any time you buy a kit and everything is not furnished,there is a certain learning curve.I've used Grainger in the past,ordered one day,and p.u. at the store the next.A dial caliper and a notebook will help you get the fit you are looking for.Also trying to wallow a drill bit around doesn't get consistency, Depending on the application and material,a few thousandths ,makes or breaks when maching a special hole,thats why you will probably end up with a non hard ware store driil bit.Good luck,keep us informed.

 

[dnschmidt]

Why not just measure the rivnut your using with a dial caliper and then use the next biggest sized drill on the Starrett drill chart? That's what I do and that seems to work fine. I use Astro's rivnuts and so far I've use the 6mm size and the appropriate drill for the 6mm Astro seems to be 23/64"

 

[tarbellb]

We're currently in the manufacturing stage of a tool just for this, single bit that does SAE and Metric Rivnuts for 22-30 different sizes and brands of rivet nuts.

Also, it comes with a magnetic chart

Just dangling the carrot are we Astro

Cant wait, I am inching closer to buying your new drill adapter version for rivnuts and this will send me over the edge.

Keep up the good work.

_ oh as others have mentioned, I will usually cross reference the metric standard to whatever I have in SEA or whatever is close enough.

 

[TipsyMcStagger]

Before you spend your money or mess up the project,that asking advice and trial and error is a good thing...Also trying to wallow a drill bit around doesn't get consistency, Depending on the application and material,a few thousandths ,makes or breaks when maching a special hole,thats why you will probably end up with a non hard ware store driil bit.Good luck,keep us informed.

Yes, I'm not depending on wallowing the hole with the wrong size drill bit. It was all I had at the time and I wanted to try to set one of the rivnuts. As mentioned above, I've ordered some metric bits.

Why not just measure the rivnut your using with a dial caliper and then use the next biggest sized drill on the Starrett drill chart? That's what I do and that seems to work fine. I use Astro's rivnuts and so far I've use the 6mm size and the appropriate drill for the 6mm Astro seems to be 23/64"

I searched online and what I found indicated that a 23/64" bit would be proper. In my case it was too large. I've never heard of the Starrett drill chart but when the new bits arrive, I'll use measure the rivnut with a caliper and go from there.

_ oh as others have mentioned, I will usually cross reference the metric standard to whatever I have in SEA or whatever is close enough.

I tried that and close enough didn't work with these rivnuts.

The bit should be here tomorrow. I'll report back.

Thanks for the continued feedback.

Tipsy

 

[Bellaireroad]

It must be that your tool spins the nut as it is tightened . That's why you are needing to get it to bite in the hole. If you had a lever action like this

You could make the hole big enough to just slip the rivnut in. I gave up on the drill bit tables, and just match up the back of the bit to the end of the rivnut, no problem so far


Sent from my iPhone using Tapatalk Pro

 

[TipsyMcStagger]

It must be that your tool spins the nut as it is tightened . That's why you are needing to get it to bite in the hole. If you had a lever action like this

You could make the hole big enough to just slip the rivnut in. I gave up on the drill bit tables, and just match up the back of the bit to the end of the rivnut, no problem so far

I don't have close to enough space (clearance) available to use a tool like that.

Hence the reason I bought this tool.

Tipsy

 

[LXCam]

Maybe I missed it but.... it's not the job of the knurling on the rivnut that stops it from turning during installation. That's the job of the static holder. If you'll snug up the assembly, then hold the fixed nut stationary you'll be able to tightened it up.

You need to buy a nutsert kit if you don't have the room for a ratchet type installation tool. Look that up and my previous comments will make better sense

 

[TipsyMcStagger]

Maybe I missed it but.... it's not the job of the knurling on the rivnut that stops it from turning during installation. That's the job of the static holder. If you'll snug up the assembly, then hold the fixed nut stationary you'll be able to tightened it up.

I'll try again in the morning and report back.

Tipsy

 

[LXCam]

Like this tool

https://www.eurosportacc.com/produc...MIypyItM7k1QIV2IWzCh0kWwyjEAQYBiABEgL31vD_BwE

 

[MikeF2316]

There's sets like this or if you're American like this that have every size (except really tiny ones) up to 1/2"

Starrett drill chart. Everybody should have one.

 

[TipsyMcStagger]

Maybe I missed it but.... it's not the job of the knurling on the rivnut that stops it from turning during installation. That's the job of the static holder. If you'll snug up the assembly, then hold the fixed nut stationary you'll be able to tightened it up.

I tried this again in one of the 23/64" holes I'd previous drilled. I assume by "static holder" you mean the tool. In order to hold the bolt head, you'd need three hands to drive the rivnut.

It's the nut that's threaded onto the main bolt that draws the bolt up to crush the rivnut. So, you hold the tool in one hand while tightening the nut with the other.

The actual bolt head is simply used to remove the bolt after the rivnut is installed. In fact, the first version of the tool didn't have a bolt head. It was added in version two to simplify removing the tool. The YouTube video below demonstrates the first version of the tool, without the bolt head.

The attached image shows the current version, with the bolt head.

Starrett drill chart. Everybody should have one.

Very helpful. Thanks.

Tipsy

 

[TipsyMcStagger]

The 9mm drill bit definitely worked better but I'm finding it way too easy to strip the threads out of the rivnuts during installation. I'm doing this while installing them in scrap and I'm able to visually monitor the compression of the rivnut.

I'm not really feeling much of an increase in resistance before I ultimately strip the rivnut. So attempting to install one where I can't witness the compression (behind the firewall) will probably make it that much more likely that this will not end well.

The rivnut assortment I bought is made in China. Are the Astro rivnuts made in the USA? I'm thinking I should try something of higher quality. Are the Atsro rivnuts available as metric assortment? I don't really need 100 pieces of M6.

Tipsy

 

[Astro_Pneumatic_Tools]

Sounds like a problem with the tool not the rivet nut, you should be pulling a rivet nut to set it - not threading/turning it.

 

[TipsyMcStagger]

Sounds like a problem with the tool not the rivet nut, you should be pulling a rivet nut to set it - not threading/turning it.

This tool does pull it. The threads are pulling out while the rivnut is being drawn up.

You have no comment about the country of origin of your rivnuts nor whether they are available as a metric assortment?

Tipsy

 

[LXCam]

Use some antiseize on the installation tool, this will help.

 

[Astro_Pneumatic_Tools]

This tool does pull it. The threads are pulling out while the rivnut is being drawn up.

You have no comment about the country of origin of your rivnuts nor whether they are available as a metric assortment?

Tipsy

We tested three different COO's of rivet nuts in blind tests before making ours - the factory making ours in China was the best, that's the long and short of it.

We do not offer an assortment.

 

[TipsyMcStagger]

Use some antiseize on the installation tool, this will help.

Will give it a try.

We tested three different COO's of rivet nuts in blind tests before making ours - the factory making ours in China was the best, that's the long and short of it.

We do not offer an assortment.

Thanks.

Tipsy

 

[WhataTool]

We tested three different COO's of rivet nuts in blind tests before making ours - the factory making ours in China was the best, that's the long and short of it.

We do not offer an assortment.

Are there even US manufacturers of Rivet nuts?

 

[Astro_Pneumatic_Tools]

Are there even US manufacturers of Rivet nuts?

None that I know of, or that would make them for us, however I'm open to the idea if anyone wants to reach out.

Although I have been happy with ours, which we use on electric and air power tools not just hand tools.

 

[454ragtop]

Strange, I've had a nutsert tool for years, 2 in fact, one Lawson, one Snap On, that use the thread to set the insert, works excellent. Might try these nutserts https://www.lawsonproducts.com/lawson/Standard/85897.lp

 

[TipsyMcStagger]

Strange, I've had a nutsert tool for years, 2 in fact, one Lawson, one Snap On, that use the thread to set the insert, works excellent. Might try these nutserts https://www.lawsonproducts.com/lawson/Standard/85897.lp

LOL...thanks, but nearly $70 for 25 Nutserts is nuts

Tipsy

 

[66HertzClone]

I have a hand tool for installing these just like the pop rivet tools, works great. I have been getting refills on the nut-serts from McMaster Carr, they have a wide selection. A package of 10 of the 6mm size is $6.43, I do see they recommend a 9.5mm drill bit.

 

[TipsyMcStagger]

I have a hand tool for installing these just like the pop rivet tools, works great. I have been getting refills on the nut-serts from McMaster Carr, they have a wide selection.

Yeah, I'm familiar with the pop-rivet type installation tools. The problem is that I'm working in a confined space.

If the area were completely unobstructed, I'd buy a tool like the Astro 1427 (which provide better leverage than a pop-rivet style tool) and be done with it.

Tipsy

 

[66HertzClone]

Yeah, I'm familiar with the pop-rivet type installation tools. The problem is that I'm working in a confined space.

If the area were completely unobstructed, I'd buy a tool like the Astro 1427 (which provide better leverage than a pop-rivet style tool) and be done with it.

Tipsy

Sorry, I should have been clearer, I was just offering up my experience, I figured you had seen or used the hand pump tool. I was just trying to offer an alternative supplier for the rivets.

 

[454ragtop]

LOL...thanks, but nearly $70 for 25 Nutserts is nuts

Tipsy

Sorry, I was buying thru a route salesman and pricing was way less. Pretty sure the low profile type from Mcmaster are the exact same, available in aluminum or steel. Those are the ones I use with an installation tool very similar to yours, main difference my tool has kits to change thread sizes.

 

[dnschmidt]

If the rivnut is spinning while you're installing it something is wrong. Also rivnuts are not nutserts. Two different technologies completely. These terms seem to be being used interchangeably in this tread and that's wrong.

 

[TipsyMcStagger]

If the rivnut is spinning while you're installing it something is wrong. Also rivnuts are not nutserts. Two different technologies completely. These terms seem to be being used interchangeably in this tread and that's wrong.

The rivnut is only spinning until it grabs and begins to compress.

Insofar as rivnut vs. Nutsert, I thought Nutsert was a brand name like BandAid, Jello, Kleenex, Dumpster & Jetway and rivnut or rivet nut was a generic description of a threaded insert.

I didn't realize Nutsert brand threaded inserts are not synonymous with rivet-nuts.

Tipsy

 

[66HertzClone]

Here is found this explanation (?) on the SuperCub.Org web site.

Hi Speedo,

As a general rule, the term rivnut is used to describe any brand of fastener that is strictly a tubular all aluminum rivet threaded on the end...
Nutserts on the otherhand, can be had in all aluminum, all steel, aluminum body with a steel threaded inserts, or even other combinations. Wayyyy heavier and more complex aircraft than a lowly cub tend to have a bazillion scatterd through out. Including virtually every military aircraft flying. As a loose general rule, nutserts can be structural, while rivnuts tend to hang things on gingerbread. Either flavor can be had open ended or closed.
While I agree that removing a screw from a spun rivnut is a pain, IMHO it can be argued that the work to install a bazzillion nutplates around a cowling is no less of a pain than the one or two rivnuts you may have to drill a screw out of... FWIW I have done plenty of each.
The only way I want to do more than a handfull of nut plates at a time is if I was lucky enough to hit the boeing surplus in WA when they were selling the cool drills that drill all three holes for a nut plate at once...

Hope this helps,
Take care, Rob

 

[Dutch01]

Why not just measure the rivnut your using with a dial caliper and then use the next biggest sized drill on the Starrett drill chart? That's what I do and that seems to work fine. I use Astro's rivnuts and so far I've use the 6mm size and the appropriate drill for the 6mm Astro seems to be 23/64"

I follow this practice too