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General => General Chat => Topic started by: XOIIO on July 30, 2014, 11:36:27 pm

Title: Quick question, is it possible to rivet something to a blown plastic case?
Post by: XOIIO on July 30, 2014, 11:36:27 pm
Hey all, The socket set that I got second hand is good, except for the top half that holds the smaller, longer sockets. They constantly fall out resulting in a massive mess, happened again recently and I just got fed up and left it.

Now, as a solution I think it would be good to take some strong elastic, and rivet one end on each side of the little indents to hold the sockets in place, I think it might work pretty well if I had it tight enough, or at least it would reduce the chance of this happening.

The problem is, it's a blown plastic case, so I don't have access to the inside.


Is there a type or technique of rivet(ing) that would allow me to do this? I usually hear about people using a plate with a rivet but I can't really do that in this case.

Never bothered with this before, just figured I'd get a cheap hand rivet gun or whatever it's called to do this, the only one I've seen pressed on the rivet from both sides.
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: sleemanj on July 31, 2014, 12:44:05 am
Surely just a pop rivet would do?
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: pickle9000 on July 31, 2014, 12:55:23 am
Without a backing plate it's a big problem.

I had a similar problem with a case and used spray foam (insulation) and filled the voids in the case. Mine still had the ability to hold the sockets and things (at least until the case was closed).  Once filled both sides presses against each other and that kept everything in place.

If you have a chunk of hardboard try cutting it to fit in between the sides. I've seen cases with that and you then hinge the hardboard and put a bit of memory foam on it to keep everything snug.
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: allikat on July 31, 2014, 02:47:39 am
Alternative:
Spray some of that expanding foam into a suitably sized plastic bag, place it into the case, close it, and wait for the foam to set.  Use only a limited amount of foam as it will be going into a tight space.  When it's set, glue or tape the bag up tightly to prevent foam dust escaping, and it will have formed itself into a perfectly fitting pad to prevent movement.  The same technique is used for shipping things in boxes.
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: ajb on July 31, 2014, 02:48:34 am
A pop rivet might do the job without a backer plate.  Maybe give it a try on another part of the case?  Using the largest rivet you can fit and making the hole a nice tight fit will help. 
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: SeanB on July 31, 2014, 04:45:42 am
For plastic cases you can use what is called a peel rivet. This one is long, and when you pull it it peels 4 round curls behind the case that provide a good surface on the case inside to spread the load. It looks ugly on the inside, but is a very good one to use on plastic cases. You probably will have to go to a bolt supplier to get these though, not likely to be available from a regular hardware store. Only caveat is that the broken mandrel on the inside often falls off and rattles around inside.
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: XOIIO on July 31, 2014, 05:39:24 am
For plastic cases you can use what is called a peel rivet. This one is long, and when you pull it it peels 4 round curls behind the case that provide a good surface on the case inside to spread the load. It looks ugly on the inside, but is a very good one to use on plastic cases. You probably will have to go to a bolt supplier to get these though, not likely to be available from a regular hardware store. Only caveat is that the broken mandrel on the inside often falls off and rattles around inside.

Ok, I'll look in to those. It's a socket case anyways so a but more rattling won't really be a big deal. We do have a bolt supply place locally which is good, I got a tapping bit there a while ago.
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: T3sl4co1l on July 31, 2014, 06:28:58 am
If you drill a sideways hole, then insert and set a pop rivet, you might get lucky and have it hold... then the head will act as a button to help retain stuff, so you'd put it up on the side where the nubs are (that aren't doing their job).

For blind holes, there are also expanding threaded inserts and butterfly bolts, but neither seems like a very good option.

Since it's thermoplastic, you could try some more esoteric / desperate / grotesque approaches, like using a heat gun to soften and reposition the plastic, or using a soldering iron (on low..) to push it around, or weld some more meat onto it (milk jugs are probably a compatible plastic??), or embed wires in it or something.

Tim
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: XOIIO on July 31, 2014, 07:19:00 am
if only it was thicker stuff, I could drill recessed holes and put neodymium magnets in it. You can get small ones dead cheap on ebay
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: G7PSK on July 31, 2014, 08:12:07 am
Unless there is a very large mass of plastic pop or cherry rivets wil break the plastic due to the expansion forces. I have used small drive rivets or screws into plastic,these are rivets with a spiral on them that you knock into a pre-drilled hole of the right diameter often used to fix name plates etc to equipment or they were before gluing them became the fashion.
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: sunnyhighway on July 31, 2014, 12:57:37 pm
Make a slit in the case and slide in a pre-tapped metal plate and add some glue and insulation where necessary/possible.
This distributes the force applied to the connection.
Now you can put in the appropriate bolt.

The stuff needed looks like this and must be sized to the available amount of space.
Title: Re: Quick question, is it possible to rivet something to a blown plastic case?
Post by: SeanB on July 31, 2014, 07:35:07 pm
Peel rivet info here.

http://www.npfasteners.com/peel-rivets.shtml (http://www.npfasteners.com/peel-rivets.shtml)

You can order them online as well in the US of A.

http://www.grainger.com/category/blind-rivets/rivets/fasteners/ecatalog/N-8mgZ1z0jgm6 (http://www.grainger.com/category/blind-rivets/rivets/fasteners/ecatalog/N-8mgZ1z0jgm6)

Might be expensive though for you, I buy them a lot cheaper here.