Ideas for adding a thread to a custom ball top

[8BitMonk]

I have a custom ball that I want to use for a joystick balltop and am looking for any easy way to add a thread. The density of the plastic is about that of a foosball.

My thought is something similar to the tutorial below on installing brass inserts into plastic. Basically drilling a hole nearly th size of the insert and then heating up the insert and pushing it in.



Anyone other ideas?

[BorgDog]

That looks nifty.  I would be inclined to cut threads if you have a tap for the brass insert instead, maybe even combine the two methods and heat it up then thread the insert in.

[eds1275]

You can get inserts for particle board that have longer outside threads. I would drill the correct size hole, put in a few drop of glue, then just screw them in.

[8BitMonk]

Thanks for the suggestions.

I found the right size threads at my local hardware shop, they are surprisingly spendy at $2.98/per. The recommended hole size is 5/16" but I couldn't for the life of me get the thread to screw in at that size. I upped the hole to 3/8" and that's a little too big, even with super glue it wasn't solid. Going to test hot glue next and then heating the thread to see how that goes. It's a bit tricky without a drill press.

[BadMouth]

JB Weld.

[ChanceKJ]

03:10 into the video.  "So that the heat will transfer more better..."   

[RandyT]

There are probably a dozen better better ways to heat up that shaft than a soldering iron, but for a couple of one-off's, it's not a bad idea.  These are usually inserted with high frequency vibration heating (or directly molded into the part), but induction heaters, cartridge heaters, even a propane torch would probably work as well or better.

Also keep in mind that this works only with thermoplastics.  If the item in question is a foosball, it may work fine.  But they are a soft plastic (low melting point) and even with an insert of this style, it may not be very strong.  You also don't want the insert any hotter than it needs to be.  Overheating plastics will make them brittle and weaken the area around the insert.

[8BitMonk]

Thanks for all the info and suggestions.

I spoke too soon on the superglue, after letting it setup overnight it's super solid. It was a Loctite gel so it must've just took a long time to setup. Out of curiosity I tried as hard as I could (without tools) to pull them off and couldn't. I picked up some JB Weld and may still try the heating method too just out of curiosity, I have a few to experiment on.

They are actual foosballs.  http://www.amazon.com/gp/product/B00TG1YPQO/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1 I'm using for a Super Mario Strikers bartop I'm building, surprised I couldn't find other soccer related balltops out there. I like the fact that the foosball ones are grooved where the stitching is, gives it some dimension.

My next challenge is painting and protecting them. I'm going to paint them  high gloss black and white and then give a slight light black wash to bring out the seams a little more. Then I plan on using a heavy duty automotive clear coat to protect and make them shiny. Any better ways to do this? Thought about dipping them in a lacquer or plastic but I'm not sure how that would work.

[RandyT]

My next challenge is painting and protecting them. I'm going to paint them  high gloss black and white and then give a slight light black wash to bring out the seams a little more. Then I plan on using a heavy duty automotive clear coat to protect and make them shiny. Any better ways to do this? Thought about dipping them in a lacquer or plastic but I'm not sure how that would work.

Getting paint to stick to them might be a challenge.  I think protecting the surface will be a must.  If you can get your hands on a small set of two part epoxy, meant for pouring table tops,  you can mix up enough to dip them.  This material takes a while to cure, but it might be just the ticket for an even finish.  I would slather the shaft with petroleum jelly (jeez, here it comes) attach the ball and dip.  Then, allow it to cure vertically, with the  ball on the top end.  The petroleum jelly will keep the epoxy from sticking to the shaft, so you should be able to unscrew it afterward, and grind off the excess material around your insert.

Can't promise it will work, but that would be my first approach.

[8BitMonk]

Thanks for the idea, I picked up some two part epoxy over the weekend and I'm going to give it a try. I'm a little disappointed in the byoac community for not blasting 'slather the shaft with petroluem jelly' with a host of inappropriate comments. Seriously though, wouldnt' it be easier to just mask it off with painters tape.

[RandyT]

Seriously though, wouldnt' it be easier to just mask it off with painters tape.

You could try that, but if the tape is sticking to the shaft, and then becomes one with the epoxy, it might be a bear to get enough of a hold on the shaft to break that bond.

[8BitMonk]

Thanks for the suggestions on this. Figured I'd come back and link to the thread with the custom balltops I ended up making since they're not shown here: http://forum.arcadecontrols.com/index.php/topic,145989.0.html