Surf PI Pro Case Repair

[hobbes_lives]

I posted this over in the Modifications forum, but I figured I'd post it here too for a little more exposure.

While modifying my Surf PI Pro to accept a 10 cell battery holder, I made a stupid mistake and put a little nick in the black plastic case on the smooth surface right where the seal goes. It's not very deep, and is about the width of a small scratch, but is likely bad enough not to get a good seal when the case is closed. I'm looking for recommendations on the best way to fix this.

My first thought is to melt a little scrap plastic with MEK and use it as filler in the nick. I'm not sure how to get it nice and smooth after doing that though. What are your thoughts? I'm really concerned about getting a good seal after it's fixed.

(To make a long story short, I had planned to put tape on the crucial area before cutting, but then got side tracked and forgot.)

I appreciate everyone's help on this. Thanks.

 

[thinkin2]

hobbes, I don't think I would do the melt thing with plastic. Something I used to use to repair my boat hull sometimes was a product called Marine Tex, or at least I think that's what it was called. It's been a long time. Try a local marine supply store and see if they have it or something like it. It's very strong and if your problem is no more than a scratch then a tiny little bit of this would be all you need. You mix it up and then after it sets up you can sand it and paint it. But if your repair is really that small I would just mix it and fill the scratch and immediately wipe the rest off really good being careful to keep everything flush with the rest of the case. It will set up very, very hard and should do the trick. Best of luck.
Jerry

 

[John (west central FL)]

Jerry's Marine Tex suggestion is good. You can also use JB Weld which is available at most hardware stores. I would put a little more than necessary on the scratch and then sand it down with 400 or 600 wet/dry sandpaper.

John

 

[hobbes_lives]

[quote John (west central FL)]You can also use JB Weld which is available at most hardware stores. I would put a little more than necessary on the scratch and then sand it down with 400 or 600 wet/dry sandpaper.[/quote]

Good idea, but...

Q: Is there anything that J-B Weld WON'T bond to?

A: J-B Weld will not adhere to, or bond well to:

* Any flexible rubber surface
* Leather
* Vinyl
* Canvass
* Polypropylene plastic
* Polyethylene plastic

 

[hobbes_lives]

I looked up Marine Tex and it seems like the same deal as J-B Weld, won't stick to plastic...


What does Marine-Tex NOT adhere to?

Plastics like polyethylene and polypropylene, and also any unclean, oily, greasy, or otherwise contaminated surface.


Thanks for the suggestion, though.

 

[thinkin2]

How about a two part epoxy? That sets up really hard and should adhere to just about anything so it should also make a good filler. Good luck.
Jerry

 

[scubadetector]

I don't know what the case looks like but could the whole edge be sanded down to get rid of the scratch? You would have to lay the whole case on some sandpaper to make sure it is equal. Just a thought.

Can you buy a new case?

 

[hobbes_lives]

The sanding idea would not likely work out well due to the way the top portion of the case clamps on to make a waterproof seal. I think my best bet is to fill in the nick and make it flush with the rest of the case. The problem is finding something that'll work properly with the type of plastic that the case is made of. So far, I've received some good suggestions to check out.

I have sent an email message to Whites to see how much a new case would cost. Then I'd have a new case to try not to screw up, since I would mod it too.

 

[Sandpiper]

There is a two part plastic epoxy that is made, I have used it on a flip cell phone hing post and it worked very well. Plastic is very hard to mend but this done the trick for me. May give this a try. I found it in Wally World. Don't know if you can still pick it up there or not.

 

[houndawgg]

When I decide to do it, rather than grind any of the chamber walls away, I'm just gonna use AAA's, which last plenty long and will still kick up the voltage.

 

[scubadetector]

Call this number 1-800-392-3223 and ask for Tony. The housing cost is 29.12 cents. Might be better to buy a brand new one instead of trying to fix your old one. Drowning electronics isn't fun!!! Good luck.

 

[bdahunter]

Crazy Glue would work; I realize that it sounds like an easy fix but it will bond to plastic and give a very secure seal. Don't forget their slogan "You can do some Crazy things with it."

Cheers,

BDA

 

[Uptomyneck]

If the scratch is as minor as you indicate all you have to do is polish it with 600 or finer wet and dry sand paper. The "o"ring is very forgiving to minor surface variuations in they are polished.

If you do decide to use a filler then do it like this. Lightly roughen up the area with 600 grit paper. apply the liquid solution and then place the case face down on a piece of wax paper laying on a perfectly flat surface such as a granite counter top. Once it is cured just polish off the overlapping edge. That case is a hard plastic and any epoxy based product should bond.

If the nick is less than .010" deep I would simply polish it out and not give another thought.

 

[doindadiggin]

Hi all another way would be at a machine shop on there surface grinder, but you would have to take out the internals ,but maybe just buy a new one eh.terry in oz

 

[John (west central FL)]

The case is not polyethylene or polypropylene. You have nothing to loose by trying. If it doesn't stick then you should be able to scrape it off.

 

[hobbes_lives]

I was concerned about the various epoxies adhering to the plastic case since most of them stated that they wouldn't work on certain plastics, and I couldn't find anything locally that was made for plastic, so here's what I did...

I took a small amount of scrap plastic and put it in a jar with a small amount of MEK. After a while, the concoction turned into a fluid plastic. I took a toothpick, picked up a drop of the goo and put it in the scratch. I waited for that to set up, and then put another drop. This was enough to fill in the scratch and formed a small mound. I used an Exacto knife to shave it down until it was nearly flush. I then used a Q-tip that was wet with MEK to smooth everything out.

It looks pretty good and I think it will seal up fine. I don't think I'd take it down 100 ft., but for wading, it should be A-OK.

Thanks for all of the great replies everyone!