Plastic welding

Well some of you may remember I hit a patch of dirt going thru a corner last summer I almost managed to gain control but before I could stop my foot-peg jammed into the side of the road and I was thrown off the bike.

There was some damage to the fairing but the worse part was that the rear fender had torn loose from one of the bolt points, I just shattered a hole where the bolt used to be. My brother in law told me his older brother rides a VFR like mine and he said he had a rear fender that was slightly scratched up but was in better shape than mine, when he came for Thanksgiving he brought it with him and just let me have it for nothing. Thanks Bro!

Well it was cracked in several places but it did not have as severe damage as my fender so I decided I would try to repair it. I went to the welding supply shop, they sell a gas plastic welding kit, but I used a hot soldiering iron and some ABS plastic sticks, I just doped in some ABS over the cracks on both sides and smoothed it over as best I could, I had to do this over in a few places cause the extra plastic did not take hold in some cases.

This is a pic of the where I busted a hole in my fender, its about 30 degrees outside so I just took this one inside, this is where it broke.

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender11.JPG)
Here is where I welded some of the cracks on the inside

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender01.JPG)
You can see where he scratched it

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender03.JPG)
The point where the rear brake lights was cracked on both sides, I really had to fuse in allot of ABS to fix the cracks

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender04.JPG)
I began to sand out the rough welds here

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender05.JPG)
It is nice having a free fender to experiment on! I don't think I would have attempted to do this on my own fender.
Here I took a round file and shaped the welded part to make it look like it was before I welded it.

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender07.JPG) (IMG:http://www.vfrdiscussion.com/uploads/fender/fender08.JPG)

A close up of where I filed it back to shape

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender10.JPG)

I have allot more sanding to do and some spots don't look quite right, the upper holes where the frankenbolts go need allot of work to get them smooth and round. I will post more pics as the work progresses.

(IMG:http://www.vfrdiscussion.com/uploads/fender/fender06.JPG)

HS, Are you using the soddering iron type plastic welder or the hot air type? I have soddering type and I found the same problem of the fill rod not bonding well to the parent plastic sometimes.        
 :idea:         I found using a torch and flat screw driver works better than the welder and make stronger welds. It takes some playing with, learning different methods and strokes to stitch the plastic together on the first pass and fold it over on the second pass. I've done over 100 welds so far with this method with few failures and stopped using the welder all together. The hot air type may be the trick ???

:beer:

I was just looking into welding a replacement for my rear seat cowl tab and came across this site, Plastifix. I wonder if it is any good. :P

Soldering iron, I had to redo 2 welds because they were not bonding well enough,  I found if I hold the iron in the weld a bit longer and let the plastic around the crack become soft it has a better bond when it cools down,  I have a nice fat iron that smoothes over nice.

That plasifix is for Urethane plastic, not compatable from what I read, you have more info on that stuff? ?There are some ABS glues out there that are good, ?The welding actually was best for me since there where actually holes to fill.

Great topic, H.S.

I was thinking of this stuff:

plastex

But I haven't bought it yet.

PlastiFix is made by a urethane company but claims to work on:

PlastiFix works on most rigid plastics. Plastics like...

Acrylonitril Butyl Styrene (ABS)
Polycarbonate (PC)
Poly Vinyl Chloride (PVC)
PA (nylon)
SMC
Fiberglass

Try this web site for an explaination:
urethanesupply.

OHH much better and mouldable,  I wonder If I can rebuild my mount with that stuff.

some correction for you:

Acrylonitril Butyl Styrene (ABS)
 (The correct name is Acyrlonitrile Butadiene Styrene)

   The easiest and cheapest place to get glue and adhesive for ABS is at your local plumbing supply store...they should have plenty of ABS glue (ABS plumbing pipe)

  The problem of the Plastfix stuff is that it is an adhesive and therefore try to bond the 2 plastics surfaces with adhesive layer.  The ABS plastics at the plumbing store is actually an ABS solvent, and thus melts the ABS and then once it evaporates, the 2 surfaces are melt bonded together and thus similar to the state before the part was broken.

Plastics

Rode down to the Ace Hardware, the helpfull hardware old guys! ?Sure enough they had ABS glue in a small enough container for me to use.

OK I played with the free faring and decided to try to fix the broken tab on my rear fairing. It has a few scratches and a broken mount point which is better than the other fairing I had to weld together, ?6 welds. ?I fitted it on the bike and it did not fit as well, the rear light would not fit right. So I thought I can fix that mount on the original fairing.

Here you can see how the the plastic broke around where the bolt mount is.

(IMG:http://www.vfrdiscussion.com/uploads/fender/weld01.jpg)
I cut off the good mount on the other fairing and used a dremel tool to clean up the edges, I just hacked it off with a hand saw.

(IMG:http://www.vfrdiscussion.com/uploads/fender/weld02.jpg)
I had to go and ?clean up the half broken pieces off the original fairing, I used the dremel to do that too.

(IMG:http://www.vfrdiscussion.com/uploads/fender/weld03.jpg)
I enlarged the hole and twisted the transplant piece to fit as best it could, I used some abs glue to hold it in place, it stuck out in several places.

(IMG:http://www.vfrdiscussion.com/uploads/weld04.jpg)
I melted some abs plastic into the holes and gaps on both sides front and back, and fixed the crack at the bottom, I smoothed it out as best I could.

(IMG:http://www.vfrdiscussion.com/uploads/fender/weld05.jpg)
The back I really added a lot of that melted ABS

(IMG:http://www.vfrdiscussion.com/uploads/fender/weld06.jpg)
I began sanding it smooth It is a very strong weld.

(IMG:http://www.vfrdiscussion.com/uploads/fender/weld07.jpg)

Great progress.

The previous owner did that to one of my side fairings, I recognize the fugly black lumpiness. You gonna paint it yourself?

I dont know, I am not the best painter out there, maybe just fix all the broken stuff and have a pro paint it.

I just bought a Plastex plastic repair kit from Eastwood for $19.99 plus $5.99 for 3 additional molding blocks. Just do a search on the site for plastex. I will advise how the kit works to fix my missing seat cowl tab when it comes. ?:D

Oh wise list,

I went to Home Depot yesterday and asked for ABS glue.

They said that PVC glue was the same.  I bought it with major doubts and wanted to check with the list before I opened the package.  According to the previous replies, PVC falls under the Urethane category.

What to do?

Paul

MrCleanVFR, Nov. 13Oh wise list,

I went to Home Depot yesterday and asked for ABS glue.

They said that PVC glue was the same. ?I bought it with major doubts and wanted to check with the list before I opened the package. ?According to the previous replies, PVC falls under the Urethane category.

What to do?

Paul

PVC glue is definately not the same as ABS glue. Sometimes it will work, but they have different solvents in them. I believe the solvent in ABS glue is MEK or Acetone. Don't know what is in PVC. Good luck.

I have had to repair my fairing. I show alternative methods to Slammer's. When I gave the parts to the spray painter he gave them to his welding specialist, who is a disadvantged black woman but a very skilled plastic welder. She then brought my work up their standard using a soldering iron just as Slammer has shown.

Plastic Identification
Honda are kind enough to tell us what plastic polymer is used to make each part. Here are photos of the fairing side panel & front fender of my 5th gen VFR.
Side panel marked PA6 + PPE + GF10
Fender ABS


(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_210888.jpg)
fairing PA6 PPE.jpg


..


(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_527796.jpg)
fender abs.jpg


What does this mean? Hewlett Packard give a comprehensive listing
HP Plastic Identificationhere for the internationally agreed codes to identify plastic polymers (see end of reference where ASTM & ISO standards are listed). The ones you are likely to see on a motorcycle are:

ABS Acrylonitrile-butadine-styrene Fenders & Fairings
PP Polypropelene Air Filter housing, Water bottle
PA Polyamide (=nylon.?Delrin?) Fairing side panel
PE Polyethelene
PC Polycarbonate Screen

The side panel of the fairing is made of a blend of PA6 + PPE + GF10
PA6 is nylon 6. There are variations on the molecular arrangement of nylon, 6 66 11 & 12 are the ones I am aware of.
PPE is Poly(pheneleneEther) which is made by GE under the name ?Noryl?
GF10 is 10% glass filling. See page 7 for confirmation of this. Glass filling in injection mouldings, like the fairing side panel, is in the form of minute glass beads ? don?t expect to see glass fibres.
The front fender is pure ABS
The upper fairing cowl is marked ABS + PE.


Alternative method for plastic welding.

The real tool to use for plastic welding is a Leister hot air gun. Their US agent is Malcolm http://www.malcom.com/products/pwk.php Malcom
The home page is http://www.leister.com/ Leister but the information is only available as a small pdf download; go plastic welding\downloads\car repairs (205 kb).

I was able to hire a Leister tool here in Cape Town. I got hold of a smashed fairing from which I cut thin strips as welding rods. That way I had a welding rod that perfectly matched the fairing I was fixing. You can only weld a plastic with the same plastic, you can?t mix them as they don?t stick to each other. (Actually you can get plastics of the same family such as PE, HDPE & PP to stick together because they are closely related)



(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_189384.jpg)
Leister & nylon.jpg


First Dremel the cracks open from the inside almost through to the front so that the softened plastic can fill the crack. (My tool is the German equivalent, Proxxon)


(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_162397.jpg)
proxxon cracks 2.jpg


In the case of the boss for the cap-screw which had completely broken off I sanded the paint away on the inside with a flap wheel so there was good clean plastic to weld to. I clamped the broken-off boss in the correct position before welding it back into place


(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_55278.jpg)
fairing inside ready to weld.jpg



(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_356608.jpg)
nylon stick in crack.jpg



(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_602793.jpg)
side panel & flap disk.jpg



(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_670317.jpg)
nylon welded on.jpg



(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_43589.jpg)
bolt boss fixed.jpg


Nylon absorbs I,8% water by weight. When you heat the fairing with the hot air gun this water boils which causes the nylon to bubble as you see in the pictures. You can iron it smooth with a soldering iron as used by Slammer. http://www.indianplasticportal.com/pa6.html Nylon is hygroscopic (This makes nylon swell as it absorbs water so it is necassary to boil nylon in water when making bushes so that it is saturated before machining to final size)


Bonding Plastic

A good site for information on bonding plastics is Special Chem
You need to register before gaining access to the site. Go to Resources & search for Solvent Cements. It brings up an informative article.

For the ABS front fender I chose to solvent cement the parts together. I got the correct solvent cement for ABS. Locally it is called Clarite 6030 but Googling on that seems to indicate that it is a local product only. It is a mixture of Dichloro Methane, Nitro Methane & TetraHydro Furan. The manufacturers make 4 solvent cements, all have Dichloro Methane, three also have Nitro Methane, one has Trichloro Ethylene & one has Ethanoic acid. So the first two are the main solvents for abs it would seem. These solvent cements are also used on HIPS (high impact polystyrene), acrylic (?Lucite? or plexiglass), Polycarbonate (?Lexan?) & PET(g) (crackly pop bottles). Plumbing fittings are made either of ABS or PVC & you can get solvent cements for each. We don?t have ABS fittings in South Africa. Since MEK is a solvent for both PVC & ABS it is possible that a cement will work with both. Solvent cements work by dissolving the plastic to make it fluid, the fluid plastic then flows together then the solvent evaporates and the plastic parts are welded together. Adhesives are different; they mechanically attach to the surfaces of the two parts and hold the parts together. Cheap solvent cements have fillers & extenders added to slow down the evaporation speed to make working with them easier but the fillers detract from the strength of the weld.

Clarite 6030 is like water. To apply it you use a small syringe. (A swab lets it evaporate before you can do much with it).



(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_538415.jpg)
abs solvent & hypo.jpg


This picture shows the crack in the front fender with a needle stuck into it to open it so that the solvent can penetrate. The Clarite in a glass bottle, a small piece of abs to be cemented inside across the crack & the hypo.


(IMG:http://www.vfrdiscussion.com/forum/uploads/1131761078/gallery_4545_662_208120.jpg)
abs cementing


This picture shows abs being cemented for the indicators (turn signals?). I have used a lot of clamps to apply even pressure. Do not tighten the clamps much; they are there to hold the new abs lightly against the fairing. Too tight & you squeeze out the solvent & it does not work. It helps to sand the surface of the abs to break the skin making it easier for the solvent to get at the plastic

The Clarite softens the abs almost instantly, then it evaporates and the two surfaces bond together. It works brilliantly. What is particularly nice is it has no effect on the paint at all. It ran all over my front fender as I injected it into the little crack but the paintwork was untouched.

There is no readily available equivalent cement for nylon. I quote from specialchem4adhesives

Nylon is a difficult material to solvent cement; however, it can be done if the proper solvents and technique is employed. Recommended solvents consist of aqueous phenol, solutions of resorcinol in alcohol, and solutions of calcium chloride in alcohol. Resorcinol-ethanol is generally considered safer to work with and is generally preferred. A bodied cement using calcium chloride and ethanol combination is used for food contact or potable water applications. Solvent cementing is recommended only when the mating surfaces are smooth and very close fitting. Where gap filling is required, an adhesive would be a better method for joining.

That's great.

I found this very informative and well illustrated link on repairing plastic.
http://www.advrider.com/forums/showthread.php?t=195528
Pelican cases are Polypropylene which is extremely difficult to get anything to stick to.

(Sorry but I don't see how to embed a link with this revised version of the board)

tok tokkie, Feb 8 2007, 11:42 AMI found this very informative and well illustrated link on repairing plastic.
http://www.advrider.com/forums/showthread.php?t=195528
Pelican cases are Polypropylene which is extremely difficult to get anything to stick to.

(Sorry but I don't see how to embed a link with this revised version of the board)

Great thread (the adventureforums one), not specifically about ABS repair, but nonetheless, pretty cool