This web page is put together to share the information I gathered while investigating rivets and their installation in pinball machine parts. It's broken down into the following sections (click on pictures for their full image):
My investigation into rivets used in pinball machine parts started when I needed to replace a broken plastic on my World Cup Soccer '94 pin. |
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The removal of the "Kick" plastic is pretty easy, so there's no problem there. To replace the plastic though, requires the removal of the stainless lamp support bracket for the "Striker's Hideout" lamp. The metal bracket is joined to the plastic via rivets. |
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Here you can see the rivets have been clinched/set with a back up washer used for additional support. |
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I used Dremel with a carbide tip to grind/shear off the back of the
rivet. |
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Here you can see the progress of grinding off the back of the rivet and back up washer. Quite a bit of heat can be generated by grinding the rivet. This can be a problem if the rivet top is against plastic and not metal as is the case here. If more than one rivet is being replaced, alternate moving from one rivet to another until the job is done. The point is to take your time and go slow, if you're in a hurry use a wet cloth to help cool down the rivet. |
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Here you can see the Striker's Hide Out lamp support has been removed from the original plastic. Also in the picture is the new "Kick" playfield plastic that has yet to have the lamp supported joined to it. |
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After searching local and distant fastener companies, I learned the rivet type used in pinball machines is called a semi-tubular rivet. It's semi-tubular because the top half is solid and the bottom have is like a tube. The tube part is clinched, or flared, to join and hold the work pieces together. I purchased two lengths (6/32" and 7/32") of the 1/8" diameter (distance "A") rivets. If I had to place another order, I'd also pick up the 5/32" length rivets to cover more possibilities and they're cheap too!
Hanson Rivet & Supply Co. I believe the minimum order is $25. Here's what I ordered.
Notes
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 Rivet specifications |
The tools used to clinch/set semi-tubular rivets is a piece of hardened steel that's like a punch. They come in different sizes based on the rivet diameter size. This one is for 1/8" diameter rivets.
Another tool is used to securely hold the rivet head in place.
You can see the tool's concave portion the receives the rivet
head.
Company: Tandy Leather Company |
 Rivet setting/clinching tool tip  Rivet head tool |
Hanson Rivet Co. wanted around $225 for a hand tool to clinch the rivets. This was way out of my budget, so my friend and I put our heads together to build rivet press out of some scrap metal. Fortunately for me, my friend is an avid welder so actually building the press was something I didn't have to do. The press is built out of angle iron, 3/4" all thread, nuts, and bolts. The all thread was drilled out to receive each rivet tool that holds and clinches the rivet. A nut is welded at the end of each all thread piece. A bolt goes through the end nut and is used to tighten and push the rivet tool. This clinches and sets the rivet tubular portion. You can easily control how much pressure is used to clinch the rivet based on how much the end bolt is tightened. Besides building a press from scratch, another idea is to use a drill press. The clinch tool could be tightened in the chuck and then a downward force could be applied. After my custom press was built, I later saw on a rec.games.pinball a C clamp like tool to clinch the rivets selling for about $45. I don't know if it includes the clinching part to set the rivet. There are a number of ways to clinch semi-tubular rivets whether it be a custom press, drill press or some other tool. I would caution against using hammer because a slight slip could spell disaster for a new playfield plastic. The force to strike the rivet clinching tool also can't be accurately controlled. I'm real happy on how my custom rivet press turned out. I have to thank my friend again for building it. Half the fun of this project was designing and building something from scratch and seeing it all successfully work.
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Here's a close up of one end of a drilled out all thread piece that receives a rivet tool. The all thread piece is adjustable by the large nut welded between the two angle iron pieces. A back up nut is also used to keep the all thread piece in place after its final adjustment. |
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Here's one end of the press with the rivet clinching tool loaded. |
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Here's the press ready to go with both rivet tools loaded. The press is adjustable by the all thread pieces moving back and forth. Also adjustable are the rivet tools based on the end bolts. The press is clamped down with Quick Grips to keep it steady. Only a single 1/2" wrench is used to tighten the end bolt going into the rivet clinching tool. The other tool that backs up the rivet head remains stationary. |
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Be sure to use the correct rivet length for the job. If the rivet is too short it won't have enough material to clinch and securely hold the playfield pieces. If it's too long the rivet will clinch nicely, but the playfield pieces won't be tightly joined together. Here's a section out of Hanson's catalog on how to determine the correct rivet length. It's a combination of the total thickness of all materials plus a clinch allowance factor. A 1/8" diameter rivet has a clinch allowance of .074 (just over a 1/16").
This picture illustrates the correct rivet length. The overall rivet length extends about 1/16" past the back up washer. |
Determine correct rivet length
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Here the rivet tools are lined up in the press with the playfield pieces and new rivet. To clinch/set the rivet, all that's needed is the gentle tightening of the outside bolt to push the rivet clinching tool.
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Here's how the new rivets turned out after using the press to clinch them. The back up washers provide support for holding together the playfield plastic and stainless steel lamp support. The application of back up washers is important where the rivet is clinched against plastic, otherwise it usually isn't needed. Also note there is minimal splitting of the clinched rivet's tubular portion due to using the correct length.
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Here's another picture showing the top view of the stainless steel lamp support and playfield plastic. The rivets are nice and shiny and look good as new. |
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Here's the new assembled playfield plastic installed back in the pinball machine. A plastic washer was also installed in between the plastic and playfield post to help protect the plastic from breaking. Plastic washers can be bought at http://www.thekingofpayne.com/. |
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