videoarizona Posted August 27, 2014 #1 Posted August 27, 2014 I made a piece of plast-aid plastic about 3/16" thick and about 2.5 inches by 1.75 inches. I made the tab in a Playdough mold....mixed and poured into the flat mold. The piece actually came out looking very close. When it was hard enough not to drip, I took the mold and pressed it against the ABS plastic I wanted it to bond to. About 3/4 of the surface of the new piece was bonded to the original ABS piece. Let it harden for over almost 2 hours...made lunch...checked Email...spoke to a friend on Skype, etc..(it's a 15 minute harden process) Went out and peeled off the mold. Looked rough but good and really stuck on the ABS. Took a dremmel and softly sanded the shape smooth. Including the two 1/2 inch holes I had in the new piece from the mold....(used to press the side cover into). I inserted the rubber grommet in the larger hole. All is well...or so I thought. When I went to press the side cover in, the new plast-aid piece broke. Shattered into pieces with a few pounds of side pressure. So..the question is...did I screw up or is side force not very strong with Plast-aid? I have an email into the company...we'll see what they say. Interesting....but I'm learning...not sure what though at this point!
Donvito Posted August 27, 2014 #2 Posted August 27, 2014 I used JB Weld to replace tabs. Still holding after about a year. Here's my post: http://www.venturerider.org/forum/showthread.php?t=82111&highlight=tabs
videoarizona Posted August 28, 2014 Author #3 Posted August 28, 2014 Thanks, Vito. That was going to be my next attempt. Already bought some of the JB Weld! Appreciate the write up....and pictures!!! david P.S. like where you live. My oldest cousin has a 2nd home there. He and his wife ride HD's. I stayed a few days in the area and liked it!
Donvito Posted August 28, 2014 #4 Posted August 28, 2014 Thanks, Vito. That was going to be my next attempt. Already bought some of the JB Weld! Appreciate the write up....and pictures!!! david P.S. like where you live. My oldest cousin has a 2nd home there. He and his wife ride HD's. I stayed a few days in the area and liked it! Thanks. Let me know if you decide to visit again.
Flyinfool Posted August 28, 2014 #5 Posted August 28, 2014 2 things. 1. You said that you let it firm up before attaching to the ABS part. Once any epoxy has started to harden it can not be applied to another surface and expect a good bond. If it has started to cure, some of the chemical bonds have already happened and are no longer available for bonding to the other surface. 2. Epoxies bond by conforming to the surface irregularities. To get a decent bond you can not have a smooth surface. The more you rough it up with sand paper the more and bigger the edges that the epoxy has to hold on to. What I have done for missing tabs or other parts of ABS is to get a sheet of ABS of about the correct thickness. I get mine at a local Hobby shop or from the scrap bin at work (we make a lot of parts out of sheet ABS). I cut out the replacement part out of the sheet of ABS to as good of a fit as I can get. I will also clean up the edges of the broken part to give nice straight lines to make fabricating the new part easier. You can also form the sheet with some heat if what you need is not a flat part. I then bond it in place using Plumbing cement made for ABS pipe. This type of cement chemically melts the plastics and welds the two parts together. If it is a structural area like a tab, I then coat the area with the cement and add a piece of fiberglass cloth (also from a local hobby shop) pressed into the fresh wet cement until the cloth is clear, while it is still wet, but partly cured, I will apply a little more cement and rub it thru the cloth. Once cured over night, the new tab will now be stronger than the original tab. Fill, sand, prime, and paint to suit. I have a broken bag lid with a big chunk missing, I really should do a step by step write up on this method some day. It is very strong and easy to do.
Huggy Posted August 28, 2014 #6 Posted August 28, 2014 On fixes like that I reinforce the replacement tab with fiberglass cloth when I attache it to the panel. And I use plastifix.
Prairiehammer Posted August 28, 2014 #7 Posted August 28, 2014 (edited) 2 things. 1. You said that you let it firm up before attaching to the ABS part. Once any epoxy has started to harden it can not be applied to another surface and expect a good bond. If it has started to cure, some of the chemical bonds have already happened and are no longer available for bonding to the other surface. 2. Epoxies bond by conforming to the surface irregularities. To get a decent bond you can not have a smooth surface. The more you rough it up with sand paper the more and bigger the edges that the epoxy has to hold on to. What I have done for missing tabs or other parts of ABS is to get a sheet of ABS of about the correct thickness. I get mine at a local Hobby shop or from the scrap bin at work (we make a lot of parts out of sheet ABS). I cut out the replacement part out of the sheet of ABS to as good of a fit as I can get. I will also clean up the edges of the broken part to give nice straight lines to make fabricating the new part easier. You can also form the sheet with some heat if what you need is not a flat part. I then bond it in place using Plumbing cement made for ABS pipe. This type of cement chemically melts the plastics and welds the two parts together. If it is a structural area like a tab, I then coat the area with the cement and add a piece of fiberglass cloth (also from a local hobby shop) pressed into the fresh wet cement until the cloth is clear, while it is still wet, but partly cured, I will apply a little more cement and rub it thru the cloth. Once cured over night, the new tab will now be stronger than the original tab. Fill, sand, prime, and paint to suit. I have a broken bag lid with a big chunk missing, I really should do a step by step write up on this method some day. It is very strong and easy to do. Plast-Aid is not an epoxy. Although I have been unable to identify the plastic that is the powder (since it is white and the particles are spherical, I speculate it is Acrylic), Plast-Aid is composed of this powdered plastic and a solvent (METHYL METHACRYLATE). The solvent is mixed with the powdered plastic and until the solvent flashes off it can be a viscous liquid or a paste (depending on the ratio of solvent to powder). The solvent also melts the substrate to be repaired and forms a chemical/molecular bond, much like the ABS cement you (and I) use. Plast-aid works similar to the technique of mixing granulated ABS with acetone or methyl ethyl ketone (MEK) until the ABS is dissolved and a paste is formed, and while still 'wet' with solvent applying the paste to the ABS substrate where a chemical bond (melted together). For those of us without access to ABS scraps (lucky you, Jeff), several eBay sellers offer ABS sheets in various sizes and thicknesses for making tabs and such. Then a repair can be rendered using the ABS sheet material and ordinary ABS cement. Edited August 28, 2014 by Prairiehammer
Flyinfool Posted August 28, 2014 #8 Posted August 28, 2014 Same theory, if by letting it thicken up did enough of the solvents evaporate out to not dissolve enough of the parent material to get a good bond? With the exception of contact cement, I have never used an adhesive that works well to join the parts after partial drying. Don't mean that there ain't none, just I have not used one.
Prairiehammer Posted August 28, 2014 #9 Posted August 28, 2014 I made a piece of plast-aid plastic about 3/16" thick and about 2.5 inches by 1.75 inches. I made the tab in a Playdough mold....mixed and poured into the flat mold. The piece actually came out looking very close. When it was hard enough not to drip, I took the mold and pressed it against the ABS plastic I wanted it to bond to. About 3/4 of the surface of the new piece was bonded to the original ABS piece. Let it harden for over almost 2 hours...made lunch...checked Email...spoke to a friend on Skype, etc..(it's a 15 minute harden process) Went out and peeled off the mold. Looked rough but good and really stuck on the ABS. Took a dremmel and softly sanded the shape smooth. Including the two 1/2 inch holes I had in the new piece from the mold....(used to press the side cover into). I inserted the rubber grommet in the larger hole. All is well...or so I thought. When I went to press the side cover in, the new plast-aid piece broke. Shattered into pieces with a few pounds of side pressure. So..the question is...did I screw up or is side force not very strong with Plast-aid? I have an email into the company...we'll see what they say. Interesting....but I'm learning...not sure what though at this point! Did the Plast-aid break off the ABS or did the Plast-aid part you made shatter, leaving some Plast-aid still firmly bonded to the ABS?
yamagrl Posted August 29, 2014 #10 Posted August 29, 2014 I used plaxiglass and acrylic fingernail powder/liquid. About 8 dollars at Wally World. You'll find it by the hair, nails and makeup. http://tapatalk.imageshack.com/v2/14/08/29/165e7619cf67fcc4b9563d7890a03618.jpghttp://tapatalk.imageshack.com/v2/14/08/29/10a469788b87114fa6e3b2df58edb7dd.jpghttp://tapatalk.imageshack.com/v2/14/08/29/07d35ac9e6bc00361575ec889ab7cd0a.jpg
videoarizona Posted September 3, 2014 Author #11 Posted September 3, 2014 (edited) The piece shattered when I put side pressure on it....the rest stuck to the ABS. The instructions say you can let it harden up a bit then form it and stick it. That's what I did. I ended up taking two pieces of aluminum, coating it with JB Weld on both sides and let that harden overnight. It seems to be working. I sanded it some to even it out a bit, then drilled my holes and used JB Weld to attach that piece to the ABS section. I put the section back on the bike today and screwed it down snug...Crossing fingers. Heather....that looks like the same size piece I made. If this doesn't work...I'll head back to store and get some makeup stuff! Thank you! BTW, the company (Plast-Aid) hasn't yet responded to my question about why it didn't work.... On my other tab fixes I did use good old epoxy. I'm a firm believer in the West System as I use it for my boat projects. Guess I should have stuck to that. Although Epoxy needs a good thickener and fiberglass cloth as it's to brittle by itself. I didn't know we could use heat to bend the ABS. Guess I'd better find some and do some more experimenting. Thanks! Edited September 3, 2014 by videoarizona Spelling and added a sentence.
videoarizona Posted September 3, 2014 Author #12 Posted September 3, 2014 Don't know if this shop can make curves...but: http://www.emachineshop.com/machine-shop/Custom-ABS-Plastic-Parts/page472.html Download CAD software, design your part, send it in. Soon, we will be able to do this at home with our own 3D printers....on ABS!
yamagrl Posted September 3, 2014 #13 Posted September 3, 2014 The acrylic nail kit is the same methyl methacrylate stuff. At the SE Texas Md in 2013 someone had the plast-aid stuff and I noticed the smell was the same so the next time I was in Wally's I went to health and beauty and looked at the nail kits. Same stuff! The great thing about it is that you can get it anywhere...Wally's, CVS. Wallgreens... It works well with acrylic plexiglass, which can be heat formed as well. I cut the plexiglass with a rotozip. It tends to chip less. You should be able to obain the flexible molding material at a hobby shop. By the way...abs is widely available at any auto junkyard. It was widely used on cars also.
videoarizona Posted September 3, 2014 Author #14 Posted September 3, 2014 Wish I had known this before I bought the plast-aid stuff....but I know it now! Thank you for that, Heather! I heard back from Interstate plastics. Big on-line retailer. He recommended Kydex material. Easily transformed without special tools. IE, possible for us to form shapes with the stuff using a little heat... http://tinyurl.com/oo3uxm3 In reading the product liturature...looks like it's strong, not easily damaged, Stands up to impacts, scratches, comes in a variety of colors and textures....etc.. Nothing back yet from the Past-aid people. Been over a week....so don't think I'll be doing business with them again...especially now we know, thanks to Heather, that the same stuff can be had just about anywhere....
saddlebum Posted September 3, 2014 #15 Posted September 3, 2014 Check out post #15 in the following thread http://venturerider.org/forum/showthread.php?t=28291 I am a strong believer in Plastex or also carried by aircraftspruce under the name plastifix. I rebuilt my bike in 2008 with the stuff after the insurance company wrote it off. I found it beneficial to inlay fiberglass tape used by drywaller's or just plain fiberglass to reinforce my repairs or formed tabs. all is still holding well to this day and I have put on 41,000 Km (25,000 mi) since then
videoarizona Posted September 3, 2014 Author #16 Posted September 3, 2014 Ben, I have no clue how you were able to piece the fairing back together. I see the results but am completely mystified. Good job! Thanks for sharing your repair link...eyeopener for this kid!
saddlebum Posted September 4, 2014 #17 Posted September 4, 2014 Ben, I have no clue how you were able to piece the fairing back together. I see the results but am completely mystified. Good job! Thanks for sharing your repair link...eyeopener for this kid! The wide cellophane packaging tape was of tremendous help in temporarily holding pieces together during the bonding process. The plastex does not stick to it so it is also great for backing while filling holes and cracks from the opposite side. if you want to smooth out the plastex with your finger wrap some of the tape over your finger first. It smooths out the plastex real nice and no plastex sticks to your finger. The plastex also sands out beautifully so no spot putty is needed. You can add plastex at any time and sand until you have a flawless surface ready for paint.
videoarizona Posted September 7, 2014 Author #18 Posted September 7, 2014 Oh my...look what I found in my favorite electronic supermarket!! http://tinyurl.com/pp5eu7x david
Flyinfool Posted September 8, 2014 #19 Posted September 8, 2014 Oh my...look what I found in my favorite electronic supermarket!! http://tinyurl.com/pp5eu7x david Dang it, Stop posting toys like that where I can see it.........:mo money:
videoarizona Posted September 8, 2014 Author #20 Posted September 8, 2014 Ha! I was thinking of you, Jeff!
saddlebum Posted September 8, 2014 #21 Posted September 8, 2014 Oh my...look what I found in my favorite electronic supermarket!! http://tinyurl.com/pp5eu7x david I think you should go ahead and buy it. Then start taking orders for 1st gen parts. You can always build me a few free parts while you learning
Flyinfool Posted September 8, 2014 #22 Posted September 8, 2014 Ha! I was thinking of you, Jeff! You are trouble, nuttin but trouble I tell ya....... Hmmmm....... Maybe that thing would let me make the special adapter for Cowpucs snow machine to be able to send some snow down into a Green Valley somewhere.........:stirthepot:
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