69 head light washer tube broken....

[Greg L.]

What would be the best way to repair this? It's a clean break so I was thinking crazy glue or maybe epoxy would work better. The broken area is pretty much hidden with the solenoid installed so epoxy might be better especially if it should have a filet on the repair. Any thoughts?


Greg Linton
#45455

[Joe L.]

Re: 69 head light washer tube broken....

Greg-----

This type of plastic is VERY difficult to repair using most conventional adhesives/epoxies. I understand that there are some new specialty adhesives that might work, but I've not tried them yet.

[Terry F.]

Re: 69 head light washer tube broken....

Joe, if it is the type of plastic I think you are talking about, it is tough to repair. Super glue won't touch it I have some stuff called TENAX-7R, it might do it. Basicly it melts the plastic togeter. But, the stuff I really want to try is acrylic cement that is used to glue plexi-glass to plexi-glass and other plastic to plexi-glass. I saw a guy use it and it was freaky strong and basicly made the two pieces into one instantly. He would line up the two pieces and put a drop or two between them. The capilary effect would suck it right in and instantly it was fused and you could see through the joint I was at a NEON sign shop when I saw it being used. I never forgot it. Thought I might need it someday in my arsenal of fix it stuff. The plastic you might be talking about could possibly be an acrylic base. Same stuff the washer pump is made out of. Just a thought, Terry

[Chuck S.]

Bonding Plexiglass...

Terry, I've worked with plexiglass before, and I'm familiar with the bonding process you describe. I built a flow model for a graduate school research project. It only works for plexiglass, and is as dependent on the joint fit as the glue. Actually, in the case of plexiglass, the product used as cement is a common chemical that I can't remember...maybe acetone(?).

[Chuck S.]

One Other Thought...

In my opinion, getting a good repair as strong as the original part is pretty much a lost cause for plastic parts. That good clean break you're describing is a handicap, not an asset. If you can FIND a replacement, that's your best course.

Bonding some types of plastic has been a problem for decades. The degree of success is going to depend a lot on the material...if it's ABS, I've used a two-part adhesive that I found on the net that works pretty well. Some small electrical shop was selling it and it was pricey...like $13 for the dual tube syringe.

[Terry F.]

Re: Bonding Plexiglass...

Sometimes a bubble would get traped in it and you could see that. What I saw the neon sign maker doing was this. He would take his neon tubing/sign and lay it on the plexi-glass and then he would clip on these support brackets that would lift the sign off the plexi-glass. Then he would capillary fill the space between the bracket and the plexi-glass. It was a one way trip. Once glued, it was done. Looked like a lot of fun. Thanks for the responce. Terry

[Jack H.]

Until just recently....

there was no reproduction for the '69 HL washer pump and prices were generally in the stratosphere for used or NOS originals. I've sucessfully repaired several of these with broken nipples using the following technique.

(1) Take the nipple down to your local model/hobby shop. There, you'll find a selection of thin wall metal tubes in various OD sizes. Typically, you'll have a choice of brass or aluminum. Buy the smallest section of pipe that JUST slips inside the nipple.

(2) Mount a cut-off wheel on your Dremel tool and make a length of tube that's the right size to fit into the nipple as a liner.

(3) Install the tubular liner into the remaining stub end of the nipple and mix up some epoxy glue.

(4) Coat the exposed portion of the metal liner tube with epoxy making sure you get a ring of glue on the broken stub end of the nipple.

(5) Slide the loose portion of the nipple over the reinforcing tube and press it into place at the point of fatigue fracture.

(6) Clean off any excess glue from the broken joint as well as any that may have 'dribbled' off the end of the reinforcing tube inside the nipple and let the epoxy setup.

The repair should be as good or stronger than new. Use of aluminum tube leaves less tell-tale coloration to the repaired nipple than does brass tubing...

[Chuck S.]

Re: Bonding Plexiglass...

Our engineering lab made a lot of plexiglass models, so the techniques had been perfected. You use ordinary wood-working tools to fabricate the plexiglass. The joints had to be machine planed flat and perfectly smooth for good bonds. Seeing those tools used that way on plastic must make a good cabinet maker cry.

Your bubble was probably introduced in the solvent or the bonding sufaces weren't perfectly flat, and trapped the air. We used hypodermic syringes to introduce the solvent right at the joint. As you said, surface tension sucked the solvent right under to make a perfect, optically true joint...you seldom had one that didn't fill completely. It was fascinating to watch the first few times...often more interesting than the purpose of the model.

[Terry F.]

Re: Bonding Plexiglass...

What was the glue?? I remember a strong smell like acrylic?? Terry

[Chuck S.]

Re: Bonding Plexiglass...

I can't remember the name of the product except that it seemed like it was a commonly available solvent...I keep thinking it was acetone, but that was nearly thirty years ago.

An internet search turns up a name...It's methylene chloride, available in hobby stores. It doesn't ring any bells for me, but then the bell is getting pretty rusty after thirty years.

There are apparently several different cements available now for bonding plexiglass, but not all will yield the kind of joint we're talking about. This is complicated further by companies trying to sell their own brand name...if it's a commonly available solvent, they aren't going to tell you that.

[Bernard S.]

Re: Bonding Plexiglass...

Chuck, Terry: Methylene Chloride is correct

[David B.]

Re: Bonding Plexiglass...

Don't know if you can still get it, but the solvent/welding chemical for plexiglass is MEK (methyl ethyl ketone). I have used it many times. Its very nasty stuff - use good ventilation and keep it off your skin.

[Chuck S.]

Re: Bonding Plexiglass...

Last time I looked you could get straight MEK in gallon cans at Home Depot...if you can stand a few other contaminants, MEK is the primary component of lacquer thinner. Even as lacquer thinner, it is indeed nasty stuff.