ABS sheet or fiberglass cloth?

[Corkster52]

I just had a new to me shelter that I just put on my 99 Aspencade crack at the same place as the old one I just replaced! On the old one an entire chunk broke out while this one is cracked in 2 places. What I want to do is reinforce the inside of the of this section of fairing to stop it from cracking any further. I have 1/8" and 1/4" thick ABS sheet on hand to make a patch, but will using it be better than saturating a piece of fiberglass cloth with ABS glue? The section on the back, where the patch will be installed, isn't exactly flat, but if I use the ABS sheet I could put enough glue on it to fit the shape.

[MikeB]

You can warm the ABS either with a heat gun or in an oven and form it to fit where you want to put the patch.

I think the ABS would be better than the fiberglass. I do not think the ABS glue will harden like resin does when it is absorbed into the fiberglass cloth. When you use ABS sheet and the ABS glue, the two sections of ABS become one ABS piece. It will be stronger than the fiberglass cloth soaked in ABS glue.

Use the 1/8" sheet for the repair since that is what you have on hand. 1/16" or 3/32" would work too. I think the 1'4" is way too thick.

But you know what, you need to find out why it is breaking in that spot. Two shelters in a row tells me there is an alignment and pressure problem with the mounting.

[Corkster52]

You can warm the ABS either with a heat gun or in an oven and form it to fit where you want to put the patch.

Mike, the only oven I have is in the house. Hope the boss doesn't catch me How hot will I need to go for it to be form-able? The sheet is slightly less than 1/8" (.114 to be exact)

I was thinking the same thing about the point loading of that spot. Will double check each of the support points to see if I can find the cause.

Thanks

[MikeB]

Don't you have a toaster oven? The pieces you are going to use are probably as small, or smaller, that a piece of toast.

You will have to experiment with the temps but I would imagine it will be soft enough to mold at 200 degrees or less.

[Corkster52]

Just thinking about it, I could also cut small strips (3/8" wide or so) to go across both cracks and tie into good ABS on either side. Kind of a zipper effect. Thoughts?

[boonny]

If it will not be noticeable I can't tell from the picture, I would suggest drilling small holes where the cracks end, stops the crack from spreading.If it is not noticeable

[redbug]

Plast-aid a product made in Colorado that wingadmin reported on is the stuff for these type repairs. The lower tabs on the 1100s are always breaking and this stuff repairs and works well with the abs type plastic. I have used it on fiberglass, filled striped holes in the fiberglass and redrilled and made new threads, so far no problem. This stuff I have used on saddlebag lids, cracked side covers. Hope this helps, and no heat required.

[Corkster52]

Hard to see, but the one crack toward the back end kind of spider-webs out, so really tough to tell where the crack ends.

[Corkster52]

I beveled out the cracks from the back side and put a thin layer of ABS glue in them last night. This morning both cracks are back I have to do something different. Have ordered Plast-Aid material from Amazon.

[MikeB]

I beveled out the cracks from the back side and put a thin layer of ABS glue in them last night. This morning both cracks are back I have to do something different. Have ordered Plast-Aid material from Amazon.

To repair a crack or a broken part of the ABS, Plast-Aid https://www.plast-aid.com/ is the way to go. Either that or Plastex http://www.plastex.net/. They are both excellent products.

Had you asked in your first post how to fix cracks in the ABS, that is what I would have recommended. However you said:

What I want to do is reinforce the inside of the of this section of fairing to stop it from cracking any further. I have 1/8" and 1/4" thick ABS sheet on hand to make a patch, but will using it be better than saturating a piece of fiberglass cloth with ABS glue?

I do not know of a better way to fix a broken part of your ABS fairing than one of the plastic repair products above but if you want to reinforce it, I believe flush mounting some ABS material behind that area in question and gluing it so that it becomes part of the original ABS is your best option.

In light of the fact that you have had two different shelters crack in the same place in the same way, if you merely put the Plast-aid or Plastex over the crack and do nothing more, the possibility of the cracks returning is pretty good. You need to find out why the cracks developed and correct the issue.

I think that reinforcing the area with a section of ABS behind the cracked area will go a long way towards preventing the crack from redeveloping.

[wingdings]

hi - corky - I did mine with this stuff - used it on the back side of the panel - you get the mesh with it too - Plastic Repair Fix Glue With Mesh - Great For Body Mouldings Panels Car Bumpers -

s-l1600.jpg glue pic 1.jpg

cost me £6 pounds on ebay - set like metal ... too !! ebay item number is -351711698113 did mine a treat too !! sets in 5mins too !!

[wingdings]

MANNOL 9918 2K-PUR
Adhesives for repairing plastic surfaces
30 Grams Bottle

MANNOL 2K-PUR - two-component adhesive for structural and decoration products made ​​of plastic, metal, wood, stone, etc. Full cure for possible machining 2-3 hours at room temperature. For a long time remains flexible, it does not precipitate, resistant to weathering and aging. Store the product in tightly closed original container in a dry place at temperatures from +5 to +25 °C.

For best results, surfaces must be clean and free of grease. Some surfaces should be roughened. Squeeze glue from the double syringe and a spatula mix well both components. Apply glue and squeeze portion (4-6 minutes processing time). Resistant to strain after 8-10 minutes. Full cure occurs within 2-3 hours, depending on the ambient temperature. Do not apply the product at temperatures lower than 0 °C.

[Corkster52]

Because I have the "luxury" of having 2 damaged right side shelters to work on, I can take the worst one of the 2 and see what works. That being the case, here is what I am going to do:

On the old one, tape the painted side over the cracked area

From the inside, using a Dremel and a conical stone, vee out the crack

Apply a small amount of Acetone in the veed out area and let it dry

Thin a small amount of Oatey Extra Special Medium Black ABS Cement with Acetone and apply it to the veed out area. Because, as it dries, the surface is slightly below flush, I will need to add a bit of a second coat.

Once it has dried completely (at least 24 hours), sand it flush and roughen the areas where I will glue in a 1/16" thick section of ABS sheet.

Cut, form (2 of them, one for the experimental and one for the newer one) and roughen the ABS sheet to cover the area. There is a bit of a step where it goes, so I will warm it with a hot air cut to make it match

Coat the area where the sheet will go on the inside of the shelter, put the ABS sheet in place and put a top coat of glue over it

Dry for at least 24 hours, reinstall the shelter and the rest of the Tupperware and then take it for a long ride to make sure everything stays and does not crack.

If it all works, do the same to the newer piece.

[MikeB]

Because I have the "luxury" of having 2 damaged right side shelters to work on, I can take the worst one of the 2 and see what works. That being the case, here is what I am going to do:

On the old one, tape the painted side over the cracked area

From the inside, using a Dremel and a conical stone, vee out the crack

Apply a small amount of Acetone in the veed out area and let it dry

Thin a small amount of Oatey Extra Special Medium Black ABS Cement with Acetone and apply it to the veed out area. Because, as it dries, the surface is slightly below flush, I will need to add a bit of a second coat.

Personally I'd say you could omit this step other than taping the painted side over the cracked area.

What I would recommend is to sand the inside of the shelter in the area of the cracks down to the bare black ABS. Then, glue in a 1/16" thick section of ABS sheet. the ABS glue you will be using will more than adequately fill the existing cracks. The ABS glue already contains Acetone.

Heating and bending the ABS... I got this from Ebay through an internet search engine on how to bend ABS.

Bend ABS with Heat
The flash point of ABS is between 730 and 753 degrees Fahrenheit, but the melting point is much lower at 180 to 225 degrees Fahrenheit. This allows the use of heat to soften the ABS. After softening, bend the plastic to the desired angle and shape. ABS sheets may discolor or bubble if exposed to heat for too long.

Heat Gun
Heat guns look like blow dryers, but they generate a blast of hot air between 200 and 1,400 degrees Fahrenheit. Use a heat gun to slowly warm the sheet of ABS until it is pliable by holding the ABS in a vertical position with a vise and slowly blowing the hot air onto the plastic. Keep the heat gun moving to distribute the heat evenly over the piece. Wear heavy, heat-proof work gloves to grip the hot ABS and bend it to the correct angle.

When working on large sheets, support the ABS in a horizontal position over the workbench on top of a vise or other metal supports. While applying the hot air, turn the plastic over frequently to soften both sides and make it pliable.

Plastic Bender
Use an electric plastic bender to heat a long, thin line to make a sharp edge. Heat the outer edge of the bend to prevent buckling in the hot plastic. Lay the sheet over the electric element for 25 to 30 seconds for 1/8-inch thick sheets, 40 to 45 seconds for 3/16-inch pieces, or 1 minute for 1/4-inch thick sheets. Monitor the ABS closely, as it burns if left on the element too long. It emits an unpleasant smell and looks like browned cheese when it burns. Plastic benders do not have warning lights so use caution when heating the plastic. Unplug the unit when finished working with the ABS.

It looks like you could possibly do the repair without having to bend any of the ABS. Just cut a couple strips and glue them in place to the affected area, one high on the upper part of the shelter over the tops of the cracks and one low on the narrower part of the shelter.
I got another suggestion from someone too. You could soak the ABS sheet in methyl ethyl ketone (MEK). That will make it as pliable as rubber sheet. I have never tried it myself but you could do a test with some MEK and a short section of scrap ABS.

[Corkster52]

It looks like you could possibly do the repair without having to bend any of the ABS. Just cut a couple strips and glue them in place to the affected area, one high on the upper part of the shelter over the tops of the cracks and one low on the narrower part of the shelter.
I got another suggestion from someone too. You could soak the ABS sheet in methyl ethyl ketone (MEK). That will make it as pliable as rubber sheet. I have never tried it myself but you could do a test with some MEK and a short section of scrap ABS.

Mike, thanks for the response. I was kind of thinking along the same lines. Getting the bottom where the vent cut out is and the top of the cracks should stop any further damage. But,...now that you mention it, I do have a lot of scrap ABS pieces and a can of MEK. I will do the bend test just for kicks.

[MikeB]

But,...now that you mention it, I do have a lot of scrap ABS pieces and a can of MEK. I will do the bend test just for kicks.

Let me know how that works out.
I also found a substantial amount of ABS sheets for sale on Ebay for some reasonable prices. One such item is number 281186973126. $4.20 - BLACK ABS PLASTIC SHEET 1/16" X 8" X 12" and Free shipping.

[Corkster52]

Mike. Don't try the MEK. It definitely makes it greasy on the top...and makes a real mess, but does not make it flexible!

[MikeB]

I guess I got some bad info but I can not say it was unexpected. I guess the heat method is the best bet. I have done it with a heat gun. Just concentrate the heat to the area that needs to be bent.

[Corkster52]

I am not a patient person by any stretch, so I just stuck this one on the old shelter I have. I was able to bend it with a embossing heat gun that I noticed on another site. No doubt it will stand out in your tool box!

http://www.hobbylobby.com/Scrapbook-Pap ... 519-KA0053

[Corkster52]

Okay, so I installed a second reinforcing patch on the old shelter while the newer one is still in the ABS base coat gluing process. I installed it and put almost all of the stuff back on the bike to take it for short ride and did so with no issues.

I did also took a few photos of the fit-up of the OEM seat and the one that I was considering buying (it was on the bike when the newer shelter cracked). What a difference! The curvature of the OEM seat perfectly matches the fairing while the test seat has point loading at 2 locations. I will not be buying that seat. Just glad that it did not crack both shelters.

[MikeB]

It looks like you found the cause. Great job.

[Corkster52]

Here are the last 2 pieces of ABS reinforcement patches as they were attached to the newer shelter. Using Acetone early on to get to the bottom of the cracks so like materials (ABS) can be permanently bonded to each other just makes so much sense. Even though somewhat painful, I will now have an arsenal of ABS sheet in 1/16", 1/8', 1/4", as well as plenty of good stuff ABS glue. Because I was desperate to get my hands on anything that might work (and thank you all for your input) during the ordeal, I will also have 2 kits of Plast-Aid and plenty of JB weld at my fingertips.

[WingAdmin]

That is exactly the technique I have used to repair many ABS bodywork cracks.

First, I sand any paint away from the BACK side of the bodywork.

Next, I spread the crack open a bit, without doing any further damage. From the back, I apply ABS cement (or in a pinch, MEK - but ABS cement works better I find - I prefer Oatey Extra Special because it works really well). They idea is to get the cement on the INSIDE of the crack. I let it sit there for 30 seconds or so, then push the crack tight together. This allows the cement to "melt" the plastic, which then bonds to itself when pushed back together. Some cement will squeeze out on the front (paint) side, I immediately wipe that away to avoid damaging the paint.

After a few minutes when this has cured enough to hold, I then take pieces of ABS, cut to fit, and form (using heat) if necessary. To form, I heat the piece with a heat gun until it is soft, then press it into the repair spot.

I coat the back of the bodywork in ABS cement, as well as the repair piece, allow to sit for 30 seconds or so, then press the piece into place. Clamp together and allow to cure.

This ends up with a repair that is stronger than the original piece.

So Corkster, it appears that you have used the exact technique that I have developed. You should have no problems.

[Corkster52]

So Corkster, it appears that you have used the exact technique that I have developed. You should have no problems.

Thanks WingAdmin. The only part I didn't do is to sand off the paint side area. Unfortunately, I did not part the crack completely either, resulting in a slightly off matching perfectly on the painted side (can feel it with fingernail). It is pretty hard to see unless you look very close, but I will have to do some touch-up in that area. I did get some ColorRite base and red paint pens. Is there a quick and dirty way to touch up the paint where the cracks show using them? I have lots of Dremel stuff to do pretty much everything needed from it.

[WingAdmin]

Incidentally, using the Plast-Aid or epoxy for ABS repairs has one main problem: when they cure, they are extremely hard and inflexible. Because they are adhering to existing ABS, when the ABS flexes, and the harder Plast-Aid or epoxy doesn't, it can break free of the ABS, and the repair fails.

When repairing using actual ABS (i.e. an ABS slurry), it chemically melts the existing ABS, and the repair substance becomes part of the original ABS, instead of just adhering to it. The repaired piece IS ABS, so it flexes just like the rest of the piece does, and the repair will be much tougher and resilient.