Domed-on-both-sides rivets

[JohnK]

I was perusing the McMaster website today and saw "Domed-on-both-sides" blind rivets:

https://www.mcmaster.com/rivets/head-type~domed-on-both-sides/

These sound like a great solution for certain areas where the rivet can be seen from both sides. The only problem is that all the ones they carry require a large hole (either 1/4" or 5/16" drill bit). Has anyone come across similar rivets that will work in an 1/8" hole, or even 3/16"?

Thanks,
John

[edwardb]

I personally don't have any experience with those kinds of rivets. And haven't seen any builds where they were used. So can't help there. Seem kind of huge though for most of our uses. Curious though where you're concerned about both sides showing? Can't think of any obvious ones to be honest. Unless you're planning for no carpet or whatever. Three other thoughts about the appearance of the back side of rivets: Using the right size grip range is important to keep the crushed side minimal. I routinely see guys installing rivets with the "bad side" showing over concern about the height of the crushed side. When they shouldn't IMO. Like around the bottom of the cockpit floor that shows in the rear wheel wells. I've also found backing washers can be used to give a good appearance plus add a little strength if that's a concern. Again, with the right grip range taking into account the washer thickness as well. I've used these https://www.mcmaster.com/90183A311. Plain aluminum ones are available most anywhere pop rivets are sold.

[JohnK]

Thanks Paul. The specific application that prompted this thought was the mounting tray I built for the E-Stopp actuator (shown here (https://thefactoryfiveforum.com/showthread.php?31167-Greek-Guys-Garage-Roadster-Build-9509-(E-Stopp-parking-brake-mount-finished)&p=415574&viewfull=1#post415574)). I riveted on the mounting tabs for the tray. Now, I fully acknowledge that this is waaaay OCD as nobody is ever going to see this thing given where it's mounted, but I don't have a box and pan brake so I could foresee possibly having a similar need down the road. I agree that the ones I linked are way too large, to the point of being unusable for any need I'd have, but if a similar rivet in 1/8 or 3/16 existed it might be useful somewhere. McMaster has a "flush on both sides" rivet in 1/8" but it requires chamfering the hole on both sides.

Thanks for the thoughts on using backing washers, and for the P/N link. I appreciate it. I'll admit that I (like I'm sure many others) have a nagging concern about being able to hide the business end of the rivets under carpet, but I've seen in your build thread that the combination of Lizardskin + carpet hid them just fine so I'll suspend my disbelief and accept that this combo works on the cockpit sheetmetal. I do have 1/8" rivets from McMaster in several grip ranges on hand.

One area of particular concern about being hidden under the carpet is the battery cutoff switch. I'm now going to demonstrate the extent to which I'm stealing all your great ideas. ;) It looks to me like you doubled up some sheetmetal around the Ron Francis battery cutoff to stiffen up the sheetmetal. That switch is pretty heavy and the switching action is stiff, so I'm planning to do the same by sandwiching on a piece of .063. Given the prominent location of the switch right under the dash, I'm concerned about the extent to which carpet + Lizardskin will hide the back end of those rivets. This may be an area where I choose to go with the "flush on both sides" rivets" and install them before powder coating the sheetmetal so they effectively disappear.

[edwardb]

One area of particular concern about being hidden under the carpet is the battery cutoff switch. I'm now going to demonstrate the extent to which I'm stealing all your great ideas. ;) It looks to me like you doubled up some sheetmetal around the Ron Francis battery cutoff to stiffen up the sheetmetal. That switch is pretty heavy and the switching action is stiff, so I'm planning to do the same by sandwiching on a piece of .063. Given the prominent location of the switch right under the dash, I'm concerned about the extent to which carpet + Lizardskin will hide the back end of those rivets. This may be an area where I choose to go with the "flush on both sides" rivets" and install them before powder coating the sheetmetal so they effectively disappear.

Yes, you'll be surprised how much insulation (Lizard Skin or otherwise) and carpet will make the crushed end of the rivets totally disappear. Again within reason if the right grip range is used. Just isn't an issue in my experience. For that doubler, the back side is way under and back from the firewall, and completely blocked by the engine. You can't see the rivets from the engine side. And the cockpit side is obviously covered up. Regular rivets are fine. Really. :o

[JohnK]

Thank you!