The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Crossrodes on June 28, 2008, 10:31:10 PM

Title: Refinishing Saddlebags
Post by: Crossrodes on June 28, 2008, 10:31:10 PM
I have a set of BMW Saddlebags on my '79 R65.  One of them is badly scarred from a whoops that a PO had. :(  Right now I'm riding the bike without the saddlebags but I'd like to put them back on.  

The question is, is there any way to fill the gouges in the in the bag and paint them (the bags) so that they would look good again.  If so what type of filler would you use on the gouges?  How would you sand/finish it?  How would I get the stipple effect back, or would this be possible? Would a primer be required and lastly what type of paint and primer?

I have several years experience refinishing cars but that was many years ago and I'm not familiar with what is possible with plastics.

Oh, one last question it the material the saddlebag is made of ABS or what?
Title: Re: Refinishing Saddlebags
Post by: Rob Valdez 79 R65 on June 29, 2008, 12:12:28 AM
Matching the texture will be the hardest part, I think, and I know nothing of what you are trying to do.

Best advice I can come up with is cover it with black tape that reflects white when light hits it at night.
Title: Re: Refinishing Saddlebags
Post by: samc on June 29, 2008, 10:14:47 AM
the bags on my 84 are ABS; ABS cement from Home Desperate fixes cracks, fills gouges, etc (see earlier thread about fixing cracks). I haven't fully figured out how to restore the stipple, but poking the semi-hardened ABS with a toothbrush seems to sort-of work. Krylon Fusion paint in satin black sticks fine and is a dead-nuts match for the original color and gloss; I can't tell (really!) where the old finish leaves off and the new paint begins. A wire wheel on a Dremel cleans up roughness, and the ABS cement doesn't seem to care much about preparation, although I do an alcohol wipe. The solvents in the ABS cement are pretty aggressive. The ABS cement shrinks quite a bit as it cures; a bulge turns into a valley.

There; that's all I know.

Title: Re: Refinishing Saddlebags
Post by: montmil on June 29, 2008, 01:26:13 PM
Quote
...There; that's all I know.

Nice post. Actually quite a bit of useful info.  [smiley=thumbsup.gif]
Title: Re: Refinishing Saddlebags
Post by: Crossrodes on June 29, 2008, 02:13:01 PM
Thanks Samc.  I'll try that and let you know how it works out.
Title: Re: Refinishing Saddlebags
Post by: Crossrodes on June 29, 2008, 03:52:45 PM
Samc...somewhere in the references I fount that they referred to the ABS cement as being black.  All I can find is yellow.  Did you find black or did you paint over the yellow cement?
Title: Re: Refinishing Saddlebags
Post by: samc on June 29, 2008, 09:23:54 PM
the ABS cement I got from Home Desperate is black. Comes in a red & white can, "Oatey" brand, found in the plumbing department, about $3 as I recall. Works excellently!
Title: Re: Refinishing Saddlebags
Post by: BigJohn on June 30, 2008, 05:30:10 AM
I couldn't find it at HD. My local store didn't even have an empty space on the shelf for it so I tried Ace where I bought their last can. Apparently ABS pipes are not as common these days hence the low supply of cement.  When I applied mine to my older cracked Krausers all it did was put a film on top which pealed off easily the next day.  If I roughed the surface a lot it did stick better but I wasn't happy with it.  In the end I used spray on truck bed liner which turned out to be some kind of paint, even though they describe it on the can as being similar to the two-part type applied by "Rhino."  After a couple of weeks I'm reasonably happy with the finish and it did seal most of the cracks though it could stand another can to be applied - I'm too lazy right now to take them back off and mask them all up again. Ideally, I would recommend the quart can of two-part bed liner sold at most auto parts stores as it promises to be a genuine plastic surface when cured and would seal up the cracks, and look very nice when done. Only problem was it's $50 for the real stuff!
Title: Re: Refinishing Saddlebags
Post by: Crossrodes on June 30, 2008, 07:31:49 PM
OK.  So far so good.  

Since I couldn't get the black ABS cement I opted to buy some Methyl Chloride and scrap ABS pieces at my local plastic shop.  Using my wife's cheese grater I made shreds of ABS (My wife will now be the lucky recipient of a brand shiny-new cheese grater  :) ).  I mixed the shreds with the methyl chloride and made a slurry.  I applied this to the gouges and waited for it to cure.  After a couple of hours I began to hand sand the repairs.  Other than a few low spots the repairs look good.  I've now put on some more slurry to fix the low spots.  Hopefully tomorrow I'll be able to finish sanding the repairs and if the local automotive store is open (It's Canada Day tomorrow...a national holiday) I'll buy some paint and go to town.  

One thing I'm not sure of is how to replicate the texture of the original bags.  I'm thinking of maybe using a paint roller on the paint to bring up the texture after I spray it.  Let me know if you have any thoughts on this.

I'll let you know how it turns out when I get the next step done.

Mike
Title: Re: Refinishing Saddlebags
Post by: samc on June 30, 2008, 08:00:50 PM
the texture is pretty deeply embossed. I'm still playing with that, so keep us posted.
Title: Re: Refinishing Saddlebags
Post by: Crossrodes on July 02, 2008, 06:02:04 PM
OK so here's what I've done after some experimentation.

First I sanded filled and sanded all the gouges per my post above.  After I washed  the cover several times with soap, water and a scrubbing brush followed by a washing with thinners I sanded the rest of the cover to provide adhesion.  I then masked the reflector, BMW emblem and the aluminum (framing?) and washed it with thinners again.  I went to my local Wal-mart and bought Krylon.  I experimented with it but couldn't get the stipple effect that I wanted.  So I went to our local Canadian Tire store and bought a product called Rocker Stone Guard from Canadian Tire.  The Rocker Stone Guard is just that...it protects rocker panels from stones.  I chose it because the label said I could experiment with it and get the texture that I wanted.  Well I did and I did.

I have now put 2 coats on the cover and am very happy with the texture.  In my experiment with a scrap piece of ABS it seems to have adhered very well.  This product is paintable so I will give it a couple of coats tomorrow.  I'll let you know how it looks.
Title: Re: Refinishing Saddlebags
Post by: Crossrodes on July 03, 2008, 08:35:24 AM
OK I have painted the bag with the satin Krylon that Samc used.  

The result is acceptable however the bag does not have the sheen that the other bag has.  If I were to do it again I would experiment with a semi gloss or high gloss to see what that finish would look like.  Right now though the bag is 100% better looking than before so overall I am happy with the result.

Now I'll finish the other bag so that they match.
Title: Re: Refinishing Saddlebags
Post by: Billmc on April 07, 2017, 12:22:38 PM
So its been almost 9 years since you did this job. How did they hold up? Did you refinish the insides?
I have a pair of bags with the roundels for my '87 Mono and I'm getting ready to rebuild /re-finish them and had heard the truck bed liner type material was a good way to go. Any comments?
Thanks, Bill
Title: Re: Refinishing Saddlebags
Post by: clonmore1 on April 07, 2017, 04:03:02 PM
Interesting to see if you get a response bill.

I too need to refurb my hard saddlebags, doing some research on plastic painting.

Not quite sure what to do yet[ch129300]
Title: Re: Refinishing Saddlebags
Post by: D Mann on April 08, 2017, 09:15:32 PM
Here is the info I used to fix my bags.http://www.webbikeworld.com/Motorcycle-technical-articles/repairing-abs-bags.htm
Title: Re: Refinishing Saddlebags
Post by: clonmore1 on April 09, 2017, 01:02:56 PM
Thanks D Mann,

I don't have any holes in my bags, the finish has faded, I am looking to 'freshen' them up before putting them back onto my bike.
Title: Re: Refinishing Saddlebags
Post by: Tony Smith on April 09, 2017, 10:25:04 PM
Any of the many plastic surface rejuvenating will do the job - start with the cheapest as they all have pretty much the same chemical composition, work your way up if that doesn't do it for you.
Title: Re: Refinishing Saddlebags
Post by: clonmore1 on April 10, 2017, 02:36:22 PM
Thanks Tony[ch128077]