Plastic Repair ( ST1100 \ ST1300 )

[KoTAOW]

Plastic Repair HOW-TO

(from a post by Chuck Chiodini)

1) Sand damaged area with #150 wet sandpaper till smooth. Extend sanded area to 1/2" beyond damaged area.

2) Fill in low areas/deep scratches using J.B. Weld as body filler "bondo". Do not use fiberglass resin or regular bondo on our ABS plastic. They will work at first but will eventuallly crack and fall out due to vibration and dis-similar materials.

3) Sand J.B. Weld with #150 then #220 wet sandpaper till smooth and level with original contours.

4) Prime with flexible primer (used on car bumpers). Sand smooth with #320 wet paper. Make sure when you are finished with this step the only "scratches" you can see in the surface are #320 sanding marks. Paint does not hide imperfections, paint brings them out to be noticed. Take your time, it only takes time and patience at this step to get a perfect job.

5) Apply at least 2 coats of "base color", sand final color coat with #400 paper to remove any roughness.

6) Apply two coats of candy/metallic. Do not sand this coat!

7) Apply at least 2 coats of clear, wait 24-48 hours to dry, wet sand with #1200 paper and hand polish.

The easiest way to go is fix the scrapes and go up to step #5. Take the part to a good painter who works with car bumpers and understands the need for flexible additives in the paint. If you don't use flexible additive, the paint will look great for six months and then start to "spider crack" due to vibration/movement. Be prepared for "sticker shock" with the high price of the paint. I use DuPont "Chroma Color" urethane paint and it sells for $35/pint. Your painter will need to buy threee pints of paint (base color, candy/metallic, and clear) in addition to the flexible additive and the universal solvent/hardener. I would recommend you not use the Color-Rite paints due to their high mark-up and poor color matches (that I have seen, others have different opinions on this but I am a perfectionist).

To re-texture and re-paint the textured surfaces on a ST I used SEM #39853 "Texture Coating" the texture produced varies with the spraying distance and finger control so you'll have to practice a lot to get the texture correct. I found a very light coat from 20" away and then lightly sanded with 150 grit paper reproduces the finish so closely that you can't tell the difference from 3' away. Practice makes perfect.

To restore the color to the lowers, I used SEM #39213 "Honda Gray Bumper Coater" an exact match for my '91 and a '94 & '92 I worked on. SEM products are usually available at most auto paint supply stores.

[KoTAOW]

MORE Plastic Repair

     Getting Started

     First of all you need a liquid, solvent-type glue for plastic. These kind of glues are almost like chemical welding which they dissolve or liquefy the plastic wherever applied. When you put some on two (2) pieces of plastic and press them together, the liquefied plastic on the surface of both pieces mixes and when the solvent evaporates and everything hardens up and it is all welded together into one piece. It is not quite as strong as the original but I'll address that later.

     You can buy the right kind of glue at any well-stocked hobby shop. It usually comes in 1 or 2 ounce bottles. Just make sure the stuff you get lists ABS as one of the plastics for which it is suitable. You will also need some disposable ABS plastic scrap. If you do not have any old broken fairing parts lying around (and if not, what kind of biker are you anyway!), try asking a local dealer if they have some. If they try to charge you for broken fairing fragments leave immediately and take your business elsewhere, like around back to their dumpster!

     Now to Begin the Work

     Clean the piece(s) to be repaired thoroughly. All the liquid plastic glues I've used have an applicator brush built into the bottle cap. Run the brush along the edge of the crack(s) and capillary action will draw the liquid in all the way along the break. Hold the pieces together until set (usually 30-60 seconds). In the case of a really large break, you may want to temporarily stitch the parts together with safety wire before gluing.

     If you have (A) really large cracks, (B) significant holes to fill or (C) a repair in a highly-stressed area, you'll want to reinforce the repair with fiberglass. This is so inexpensive and easy I do it with every repair I make just to be safe. Use a fiberglass repair kit for car body work.

          Remove any temporary safety wire stitching you put in while gluing.
          Rough up the BACK SIDE of the part you're fixing (I use a wire wheel on an electric drill).
          Apply the fiberglass cloth and epoxy as per the instructions in the repair kit.
          Remember that you're applying the fiberglass to the INSIDE of the fairing where no one can see it.

     Now back to the front side of the part you're fixing. File or sand any rough areas or raised sections if you didn't get the pieces lined up perfectly (not too uncommon).

     Time to Prepare the Filler Putty

     Get that scrap ABS fairing section and just start drilling holes in it. COLLECT THE SHAVINGS: these are what you use to make your putty. I use a 3/4-inch wood boring bit that generates lots of plastic shavings quickly. Collect some of these shavings in a shallow non-plastic container. I use an empty cat food tin. Pour in a little of the plastic glue and you'll soon have a gooey mess that's basically liquid ABS. Use this goo to fill holes, scrapes and gouges. For large holes, build up several thin layers rather than trying to do it all in one go. When it's set, you can file, sand and paint it just like ABS because that's what it is. I have several round and flat files that I use to shape the final surface. Then I prime and wet sand it and get it painted.

     This DIY plastic filler putty has several advantages over Bondo and other products of that type. It has the same flexibility properties as the rest of your fairing. It has the same thermal expansion and contraction properties as the rest of your fairing. It has the same paintability characteristics as the rest of your fairing. It adheres more tenaciously to your fairing if you've done everything right it virtually becomes part of the plastic.

     Final Notes

          It takes a lot of plastic shavings and just a little solvent to make putty of useable consistency.
          Do some experimenting first.
          In thin layers this stuff hardens quickly and so make very small batches.
          Solvent-type plastic glues are highly volatile, inflammable and noxious. Use with lots of ventillation, make sure there are not any sources of flame and keep the lid on the bottle whenever possible. You can almost watch this stuff evaporate.

Addendum by Brian D. Jones

     This addendum was written by Brian and he has graciously allowed me to post it here. His experience was helpful to me and substantially adds to this discussion on plastic repair.

     The ABS "glue" sold at Lowes and other home improvement centers is a combination of MEK (methyl ethyl ketone) and ABS resin. The solvent is MEK. I first experimented with a piece of ABS pipe, cutting a 4" length into 3 pieces. I made one butt joint using the ABS compound. I made a 2nd butt joint by holding the two (2) ands together and using a small brush to apply MEK to the joint. Capillary action pulled the MEK into the joint. After an hour or so of cure time, I hit the pipe with a 2# dead blow hammer. The pipe is no longer round, but neither of the butt joints (which are the weakest form of joint) gave way.

     Next I started on the broken faring (from a Kawasaki - sorry about that). The fairng was apparently broken when the bike leaned against something in the garage. A 3" x 3" x 3" triangular shaped piece that encompassed one of the screw mounts had broken completely off and there was another large (4" long) crack in the faring below the broken wing. I held both of the areas to be repaired in place with tape and then applied the MEK from the back. The nice thing about pure MEK is that it is very thin, and it capillaries into the joint very well. The repair seems to be as strong as the original plastic. I can bend it back and forth and there is no sign ofany flex in the joint itself.

     I did go ahead and sand the back side and "painted" the back side with the ABS glue from the home center. This added several layers of ABS plastic to the back of the repair. I also threw in a couple of pieces of plastic across the crack that I cut from the pipe I was experimenting with and painted the ABS glue over them too. This was probably overkill.

     Cosmetically, it is not perfect, but it is not too bad either. The crack does try to swell apart a little, but if the pieces fit back together well, the repair looks OK. The nice part is that the repair itself is cheap. A small container of the ABS glue is about $1.00. A quart of MEK is about $3.00. For spare plastic, a 10 ft. length of ABS pipe is less than $3.00. I did get a couple of camel hair brushes - be careful - the MEK will dissolve the glue that holds the bristles in (that is why I wound up getting a couple of them :-) ). I "improved" the mechanical clamp on the 2nd brush with a pair of channel locks and those bristles stayed in place.

     I have not tested the repair for durability on the bike, but given the experience with the pipe, I do not expect any problems. In summary, the pure MEK is a great substance to work with (use ventilation), and is the "glue" of choice for ABS plastic. I did try a fiberglass repair kit first, but it pealed of the ABS with no problem at all and the joint was obviously weak. It is a waste of money.

[KoTAOW]

Original article can be viewed here:
http://home.insightbb.com/~mmartin36/Plastic.htm

Submitted by Mike Martin.

~~~

Plastic Repair

A frequent question arises, "What do I use to repair my ST's plastic body panels?" Several products are suggested:

From Raymond Stevens:

I called Electrical Connection for some of the stuff they sell to repair plastic. ($9 per tube). They said that Walmart sells some stuff called "Plastic Welder", made by Devcon. ($3 per tube). They said it works better, and is 1/3 the price. It is so! It has a 3500psi strength. That ought to be enough, eh? It's a 2 part epoxy kind of stuff (a little smelly!)

I also got some very fine fiber mesh to reinforce the repair. A real good idea, is to grind (via a Dremel drill or something similar) the crack to where there is a "V" groove the length of the crack (on the back-side, of course) so it acts nearly like a 'full penetration' "weld". Don't go all the way through! Just maybe 1/2 way. It sets in 4 minutes. Handling time in 15 minutes. Full strength in 24 hrs. This stuff actually 'melts' the surrounding plastic through a chemical process (my plastic became 'soft' briefly). When it was done, the point was rock solid! (a connection tab for a windscreen component)

I used it on a rather critical stress point nearly a year ago, and so far, it's held up just fine.

~~~

From Geoff Taylor:

I have had absolutely amazing results in many different applications, using VersaChem's "Plastic Welding System." Part #47809, It's a 2 part epoxy hybrid, in a dual syringe, available at most auto parts stores. 15 min. set time, Frigging 3500 p.s.i. strength!!! It stinks like hell, and I understand it to use cyanoacrylics in an epoxy base. Amazing stuff.

Geoff's product sounds like it's the same as the Devcon Plastic Welder. In fact, George Voss determined that both products are made by ITW Performance Polymers.

~~~

From Doug Kalmer:

When I got serious about fixing the bodywork on my once-totaled ST, I called a friend who earns a living by buying totaled cars and fixing them up like new for resale. He suggested using Mar-hyde Flexible bumper patch, it is made for ABS repair, and stays flexible, something the side covers need on the ST. It is a 2-part epoxy, sets up in 20 minutes, is really strong and easy to work with. It cost me $22 retail for the two 6oz tubes, available at auto paint stores.

~~~

From George Catt:

I'm currently doing tupper ware repair, too. Took a tip from someone on this list and saved some of my damaged plastic. Bought a pint of Methyl Ethyl Ketone (MEK) at the hardware store for $3. Cut up into small chunks some of the damaged plastic (remove the paint with a belt sander) and let it soak in the MEK. Makes a great ABS plastic glue. Takes a while to set up. Make it thick or thin as needed. I paint the edges I'm gonna glue with straight MEK first to "soften up" the target pieces. Nice thing about this is that it's using EXACTLY the same stuff that Honda uses, cause it IS the same stuff. Nother nice thing is that it's "machine-able" once cured. NOTHER nice thing is that it's cheap. Scraps should be available at any Honda shop. ;^)

I used the stuff that Doug suggests to repair a broken piece on Deba's Eclipse a couple of years ago. Works great, did the job.

I've used Plastex Plastic Repair, a product that got a good review in Motorcycle Consumer News. It's unusual in that it has a means to mold replacement portions in plastic and bond them in place. The kit includes a solvent (MEK?) plus granulated plastic, along with mixing and application tools. I bought it from [/url=http://www.eastwoodco.com/]Eastwood[/url]. Search the site for "Plastex" without the quotes. BTW, the price has dropped considerably since I bought my kit in 2000.

For a large fracture, I first opened the crack with my Dremel tool to form a Vee on the inside of the panel. This I filled with JB Weld, and sanded flush. Then I used fiberglass resin and cloth applied to the inside of the part, with several layers of the cloth for good reinforcement. The cloth extends two inches to either side of the crack for better adhesion, and the repair has lasted for over 30,000 miles with no failure. I think the key to it working so well is the large overlap, which reduces stress.

I believe that all the products mentioned will work well for the body parts of the ST. The headlight housing is made of a different plastic (polypropylene???) which does not respond to these adhesives, though. Likewise for the lower fairing and wing covers. As far as I know, only plastic welding will work for polypropylene.

~~~

Tip for repairing the lower fairing and wing covers: If you have some minor scrapes or gouges in the surface of these parts, you can restore the appearance somewhat by using a propane torch. No kidding! Remove the part from the bike and play the torch flame across the surface. The surface of the plastic will melt and the gouges will be much less noticeable. But you have to go slowly, using a minimum of heat. Do not get in a hurry. Otherwise, the plastic will bubble up and you will have a worse mess than what you started with. Repeat after me, "Go slowly, go slowly, go slowly."[/i]

~~~

Here's a quick rundown on repairing a saddle bag lid from Chuck Chiodini:

I fix and re-paint motorcycle plastic as a hobby so have some "real world" experience with this. You can probably fix a minor problem at home. The re-painting will be the hard part.

   1. Sand damaged area with #150 wet sandpaper till smooth. Extend sanded area to 1/2" beyond damaged area.
   2. Fill in low areas/deep scratches using J-B WELD as body filler "bondo". Do not use fiberglass resin or regular bondo on our
       ABS plastic. They will work at first but will eventuallly crack and fall out due to vibration and dis-similar materials.
   3. Sand J-B WELD with #150 then #220 wet sandpaper till smooth and level with original contours.
   4. Prime with flexible primer (used on car bumpers). Sand smooth with #320 wet paper. Make sure when you are
       finished with this step the only "scratches" you can see in the surface are #320 sanding marks. Paint does not hide
       imperfections, paint brings them out to be noticed. Take your time, it only takes time and patience at this step to get
      a perfect job.
   5. Apply at least 2 coats of "base color", sand final color coat with #400 paper to remove any roughness.
   6. Apply two coats of candy/metallic. Do not sand this coat!
   7. Apply at least 2 coats of clear, wait 24-48 hours to dry, wet sand with #1200 paper and hand polish.

The easiest way to go is fix the scrapes and go up to step #5. Take the lid to a good painter who works with car bumpers and understands the need for flexible additives in the paint. If you don't use flexible additive, the paint will look great for six months and then start to "spider crack" due to vibration/movement. Be prepared for "sticker shock" with the high price of the paint. I use DuPont "Chroma Color" urethane paint and it sells for $35/pint. Your painter will need to buy threee pints of paint (base color, candy/metallic, and clear) in addition to the flexible additive and the universal solvent/hardener. I would recommend you not use the Color-Rite paints due to their high mark-up and poor color matches (that I have seen, others have different opinions on this but I am a perfectionist).

Other options:

   1. Buy just the lid to the saddlebag from Honda for around $290.
   2. Hand the lid over to a plastic repair guy for around $150.
   3. Slap some bondo and touch-up paint on it and be pissed at your "ugly paint" for the ownwership of the machine.
   4. Fix the scratches with fiberglass and regular spray paint and be pissed six months from now when it looks like "poo-poo".

Happy to answer any questions. Yes...I'm anal about this but ask to see my (or any other "quality" painter's) work and you'll see why time and experience makes the difference in plastic repair/painting.

~~~

More tips from the ST crowd:

Per Michael Moore:

This is an old trick that works wonders for repairing the tabs on the inside of the ST's bodywork as well as any other application where you need strength and not looks. Super glue the tab back into place, then wet all around the re-connected part with more super glue (gotta use the regular stuff, not the gel). Then powder it all with baking soda. It dries almost instantly, and forms a Herculean adhesive. I did this on the left side panel when one tab broke off while accessing the battery, it has held like new since.

~~~

To which Rob Parker added:

I will second this. I used this method in repairing the side panels on my SR250 several years ago. It was related to me by a friend in the MC parts business. He couldn't believe that I didn't already know about it. At any rate, the parts I repaired using this method appear to be at least as strong, if not stronger, than before the breakage.

~~~

And Brian Cescot offered:

Try Permatex # 82565 Plastic Bonder. It's a 2 part process: brush on the accelerator, then use the glue to make a permanent bond.

~~~

Tim Shevlin had this offering:

Perhaps the most broken plastic parts on the ST are the lower tabs on the black garnish panel below the windscreen*. For really high-stress cases, you can add a couple of additional bolts with well-nuts in the lower corners, but for a normal tab repair, I found use of JB Weld and a single small picture hanging bracket (the kind with little saw-teeth that you nail to the back of a picture frame) to be quick, easy and cheap, as I had all the parts already. I cut one end off the bracket to use as a cross-piece which is then mounted to the remaining piece which forms the post . Some hammer and snip work is required, but the parts are so light that they can all be glued together at once. When cured, the result is a strong steel tab that fits perfectly.

* For newbies, to remove the garnish without breaking the tabs, lift slightly at the center 'rivet' and push the garnish upwards, parallel to the windscreen surface, to disengage the tabs.

© 2002 M. E. Martin, All rights reserved

[KoTAOW]

More Plastic Repair Tips

Comments by Eric J Russell:

I have used Plastex to repair plastic items. Admittedly not tupperware tabs but I have repaired automobile bits using the technique described in the Plastex instructions.

~~~

Comments by George Catt:

I've made some tabs using aluminum strap and pop rivets. Not as elegant as the plastic repair but works for me. I cut, bend, and drill, then add some JBWeld on the backside to aid in longevity before applying the rivets. Both STick and ReSTored have some of these fixes in place.

Also, for repairing panels, I put a piece of aluminum flashing to bridge the back side of the crack, using the technique above. I think the pop-rivet heads add a little Frankenstein patina. :D

~~~

Comments by Raouf Wilson:

I fixed one large missing tab, and 2 broken ones with Plastex. I am happy with the result, but will wait and see how they survive in the real world once on the road.

I hate the smell of the stuff, but it sets good and seems sturdy. The rubber mold material that comes with the kit was great to work with. Pour boiling water on it in a large cup, and after a few minutes it is very pliable. So I made the mold of the good one, of course you have to be careful with the mirror image type so you will get a left tab, to put on the right side plastic. But all seemed to fit okay.

I am happy with this type of repair, I have tried epoxy, but it didn't last long at all. Will keep trying other brands to see how they work.

~~~

Where can one buy Plastex?

There is an online store here: http://home.att.net/~g.t.motorsports/store.html

I found mine in a dusty corner of a Home Hardware store up here. It was for $25 so had been here a few years, as the new price is around $40 Cdn. I saw a video promotion from the link above that Eric posted, and video showed the logo of this store, so I thought I could try to find it. It took me 4 stores to find in my own small town store. I figured Toronto would have, but no one even heard of it.

There is a Canadian distributor here, http://www.plastex.ca/

I used the method of putting the powder in and then adding the liquid hardener. I couldn't get the needle to pick up the blob part like the video shows.