Plastic Repair

For you guys that own Secas or other plastic laden bikes. The best product for plastic repair can be had from Aircraft Spruce. The stuff is called Plastifix. It's a two part process one liquid one powder comes in a kit. The price runs from $30 to $100 depending on the kit you buy. This stuff is fantastic and there is NO mess. It even comes with a material that you can use to make a mold of a broke or missing tab. The finished repair is just as strong as it was before it was damaged. You can also use it with fiberglass cloth for reinforcing really bad breaks. Can't recommend it highly enough!! Its just fantastic stuff.

 

Thanks, I see alot of this in my future LOL

 

It really depends on the type of plastic you are trying to repair. Most of the two-parts and the epoxies are just a layer that goes on the plastic like a 'sandwich' but don't actually completely bond with the plastic. That leaves a 'parting zone' that can separate.

I have found that the best things to use are those that actually melt the original plastic, then evaporate and the original plastic will then re-solidify.

There are a number of things to use:

Again, first you should determine what type of plastic you have. Most of the ones on our bikes are ABS. There are some parts that may be a styrene or a poly- of one sort or another.

OATEY makes different cements for the different types of plastic. You work the cement into the crack, it melts some of the plastic, the melted plastic mixes in with itself, the solvent evaporates, the plastic re-solidifies, and you do some minor scraping, sanding, and buffing if needed. Then do your repaint if needed.

Personally, I prefer the Oatey ABS-Specific cement, but it is getting difficult to find anymore. Another thing that works especially well is a bottle of stuff that I get at the model-train shop for plastic-building (I can't remember the name at the moment, and the bottles are out in the shop). It is as thin as water. It works best for clean cracks and breaks with tight joints but not for stuff all broken out and rough. Hold the pieces together and use the brush to bring just a drip at a time to the joint. Capillary action will pull the stuff in. Once the joint is full, pull some tape across it to keep it tight for awhile. I like to put a pencil or something on each side of the crack and run the tape over that so the tape doesn't get stuck in the softened plastic. This stuff evaporates incredibly quick, and the plastic is pretty well set back up in a few minutes but I like to leave it for a few hours or a day anyway.

Other stuff that works is StrypEze and other types of either gel or liquid paint strippers. They all have Methylene Chloride in them, which is the chemical that softens the plastic quickly. It's NASTY stuff so wear gloves and keep good ventilation going. Don't get it on your skin or you'll start feeling it in a few seconds...............

Whatever you decide to do, again I'd suggest that you use something that will actually melt the plastic and allow it to melt back into itself and HEAL the crack rather than be a bandaid.

That's my personal preferred way of doing it, YMMV.

Dave Fox

 

Plastifix is made for ABS repairs on private aircraft. It is the best there is for repairing plastic on motorcycles! It is a fine powder with a liquid agent that cause a chemical reaction that turns the powder into solid ABS and it bonds to the mated ABS on the cowl or side panel as if it was a piece of the original plastic! Also you can use it with fiberglass cloth to use it to reinforce badly broken/shattered areas.
You lay the cloth over the area you want to reinforce. Then you sprinkle the powder over it then you apply the liquid drops onto the powder then a little more powder then a little more liquid and let it sit about 15 minutes and it is already hard. Let cure for an hour and its like a rock.
I built a new mounting tab with this stuff and its as solid as the original!! It is not a gimmick!!! There is NOTHING better then this stuff.

 

If you have a Crack in a Plastic Part ...

Drill a SMALL Hole at the very end of the crack.
This will prevent the crack from spreading until the crack is repaired.

 

Cheap soldering iron.

Scrap pieces of the same type plastic.

Weld.

Permanent repair that is stronger than the surrounding plastic.

If you want to get fancy there are kits available.

I've repaired plastic this way for 20 years. I've never had a weld fail. Just remember to use a respirator, vent hood, or do the work outside.

 

+1 very good advice. I'm a processing tech at an injection molding factory and there are some plastics that are just nasty if they get too hot. POM (polyoxymethylene) is one of these. It doesn't have too many automotive or motorcycle applications, but I STRONGLY recommend you don't melt any plastic gears you find in your car.

 

Hugger, I"ll have to try some of that sometime then-- I bet the liquid is the same stuff as in the others I mentioned. The model railroad stuff is just the liquid, the Oatey ABS cement is the same stuff but with abs already dissolved in it as a paste form. So, seems what you mentioned is again the same stuff but with dry bulk powder.

Acetone will also work, and you can make a paste with it by sanding and shaving extra abs and melting it into a 'cream'.

Yes, the plastic welding works, too, I've done that but found the others to be easier and neater.

yeah, drilling a small hole at the end of the crack is something I almost always do and never think to mention. It's almost a given............but good to mention!


Dave F

 

For any drummers out there, this also works for cymbals too

 

Moto plastic is ABS. ABS is also the plastic that black drain pipes are made from. Plumbing ABS glue is pretty much ABS dissolved in MEK (methyl ethyl ketone).

I've had some very good results with regular ABS glue from the home improvement store, even as far as making a mold out of tinfoil and filling in a missing piece.

 

No offense, but I prefer to use a product that has proven to do the job I want rather then a hit or miss home brew solution. At least I will feel confident that it will hold up at highway speeds. Where as a home brew concoction made up of materials and liquid of unknown quality could fail at any time and be disastrous no just to my self but others. Sorry no home brew remedies for me to use on my bikes!

 

" I prefer to use a product that has proven to do the job"
That would be the Oatly abs glue
" materials and liquid of unknown quality could fail at any time"
That is the motorcycle glue.
If a fairing cracks it a tab comes off, so what.
If a joint leaks in a new house and causes tens of thousands of dollars
Damage, that's another story.
Either one is going to work though.

 

What makes you think it's hit or miss? Have you tried it? Have you read that somewhere? Am I not seeing what I'm seeing, which is a panel broken into four distinct pieces, with a piece missing, edge-glued with the stuff and the missing piece filled with nothing but the stuff, surviving the vibration of my FJ perfectly fine?

How is stuff I bought at a hardware store made by a chemical manufacturer in a factory and specified for use on the type of plastic we are talking about suddenly a homebrew concoction? And what leads you to believe the motorcycle-specific glue is of higher quality? Have you done tests? Inspected the facilities? Do you have an article you can show me?

Now, I'm not saying that whatever it is you want to use is better or worse. That's because I try not to make grand pronouncements on things I don't actually know about.

 

A few years back I had another user tell me about something that was almost identical; it was called Plastex. It might be the same stuff under another name; I did notice the original site (plastex.net) isn't coming up, however.

 

Personally, I'm not using any home-brewed concoction (well, not on the bikes, at any rate..........) I'm using stuff that is SPECIFICALLY for ABS plastic.

for those who are model railroaders, too, here's the stuff that is available through your favorite MR shop.........it's called PRO-WELD by Ambroid. It is pretty expensive at $5 for a 2oz. bottle, but it's really good stuff. Just don't get it on your skin........does funky stuff to it. The chemical IS: Methylene Chloride.

Milliken.........yup, you're right. works for cymbals, too. It also works for the acrylic drums if you happen to have a set of the old Ludwig Vista-Lites.
BTW, it also works for GUITARS......just drill a good-sized hole in it with a sledge hammer. You won't hear that anoying buzz anymore............. :lol:

Dave F

 

does anyone know how to repair the textured surface on hardbags, not cracked just scraped. looks like crap and the original surface is a fine pebble grain. about 4 inches long and 2 wide

 

I haven't cone any textured repair aside from vinyl dashes. With a dash you use a textured, heat-resistant, paper over the filler when it's heat-cured. There are kits that have textured spray-finishes. I found a video, but haven't actually done a repair like that.

http://www.hbc-system.com/Hard-Plastic-repair-with-texture-coating-5211.aspx

 

I just wanted to pass along that there is a product that has proved it self in the aviation world and is superior to ALL the methods tried and recommended on the site. After all if it keeps ABS parts stuck to aircraft in the air where a failure would be a catastrophe I think its going to keep the plastic on our bikes from falling off. And its only available from aircraft equipment suppliers. The only source I know of so far is AIRCRAFT SPRUCE.
This not hardware available, this is not model shop available. ABS glue cannot be put under pressure it fails. I worked in the plastic industry for many years before my recent retirement and I have see what happens to ABS cement/solvent when it fails. It is NOT made to be put under pressure that's why its used for DRAIN pipes NO pressure. That's why plastic pipes, such as water pipes, are NOT made of ABS. 100 LBS of pressure will cause ABS solvent to fail at the point at which it was applied. I saw a guy nearly lose his head when one of these joints came apart! The guy was trying to be CHEAP and tried to use ABS instead of the proper piping.

 

As an add note Plastifix is made for fixing cracks, breaks and rebuilding parts made of ABS on AIRCRAFT!!
Does ANY of the products you use SPCIFICALLY claim to repair aircraft fairings or any other type of fairing MADE of ABS. No it does not. That's all I have to say.

 

I would like to point out that if you put hundreds of pounds of pressure into an ABS drain pipe, the pipe itself will fail before any glue does. Drain pipes are not designed to contain high pressure.

Since you seem to be such an expert on plastic, can you explain how aircraft ABS is different from any other ABS?