Proper sanding steps?

Discuss light weight issues concerning road bikes & parts.
gumgardner
Posts: 3553
Joined: Sat Jan 06, 2007 9:47 pm
Location: Pittsburgh

by gumgardner

For those who have sanded their bike, what is the proper sanding grits to start with then progress to to get a nice finished look?

Thx

User avatar
Mr.Hyde
Posts: 124
Joined: Fri Sep 05, 2008 1:03 am

by Mr.Hyde

It's better to use a blade from a cutter knife to get varnished parts clean. That is way faster than sanding and works out great. You just have to take care ever to use a sharp blade, so you will need to change it three or four times when cleaning a frame.

by Weenie


Gregorio
Posts: 1582
Joined: Thu Jul 26, 2007 10:24 pm
Location: Center of the Universe

by Gregorio

I have not sanded a frame, but have zipp carbon handlebars some old fsa cranks and a new SRAM red crank set. I found that starting with a 400 grit worked best to cut through the clear coat. Once you get thet off the paint seemed to come off rather easily. I wet sanded also. I worked my way progressively up to 1000 grit if i remember correctly. Also used some #0000 stelel wool.

I looked into having my foul weather bike stripped. In doing some research on here or fair wheel bikes forum, some one recommended soda blasting to me. I found a local person that said he would do the frame and fork and it would only take <2hrs. Wasn't very expensive. I was worried about him damaging the carbon and he said he could strip paint off of glass without a scratch.....now I am sure that glass is harder than the carbon, but I would take some old carbon bits or a cheap bottle cage or something to try first. Just to see if the results are acceptable.

DamoRider
Posts: 175
Joined: Sun Jan 16, 2011 6:27 pm
Location: Dallas, TX

by DamoRider

I have sanded my entire Ridley Damocles and it wasn't easy; at least most every logo was a painted logo and not decals under clearcoat so the process was relatively straight forward.

1. Started with 120 grit to remove all clearcoat - it will come off as white/grey dust (at least it did in my case)
2. 220 grit to remove all paint stop with this when you see the black dust (you are starting to take off carbon)
3. 600 grit all over to bring out the carbon better
4. 1000 or 1200 to finish the job

Use 303 Aerospace protectant if you want to leave the carbon raw.

Hope this helps. Be aware the sanding takes a lot of time to do areas around headtube, bottom bracket, etc...

gumgardner
Posts: 3553
Joined: Sat Jan 06, 2007 9:47 pm
Location: Pittsburgh

by gumgardner

awesome. Thanks everyone :beerchug:

User avatar
Mr.Hyde
Posts: 124
Joined: Fri Sep 05, 2008 1:03 am

by Mr.Hyde

DamoRider wrote:Use 303 Aerospace protectant if you want to leave the carbon raw.


Why? Finish?

Concerning the rest, sanding is just a waste of time, except in the corners you can't reach with a cutter blade. Give it a try :wink:

Gregorio
Posts: 1582
Joined: Thu Jul 26, 2007 10:24 pm
Location: Center of the Universe

by Gregorio

I did not put any finish on the carbon. I like the matte ud raw carbon. I do use a auto wax paste on it a 4 or 5x a yr.
These cranks get all of the winter road salt through the winter and after 2 yrs they still look the same. No apparent damage from not having a clear coat.

User avatar
Mr.Hyde
Posts: 124
Joined: Fri Sep 05, 2008 1:03 am

by Mr.Hyde

That's my point, you do not need to protect the carbon from anything that is outside. Highly concentrated acid or bases can damage the matrix, that's it.

gumgardner
Posts: 3553
Joined: Sat Jan 06, 2007 9:47 pm
Location: Pittsburgh

by gumgardner

After I sanded for a while and wet it, certain parts will dry faster and turn whitish. Is that clear coat still?

If there are still white scratches that means there is still clear coat, right?

DamoRider
Posts: 175
Joined: Sun Jan 16, 2011 6:27 pm
Location: Dallas, TX

by DamoRider

Yes, if you are seeing white that means there is still clear coat in place. You will have pure black dust when you hit carbon.

gumgardner
Posts: 3553
Joined: Sat Jan 06, 2007 9:47 pm
Location: Pittsburgh

by gumgardner

If I get to the carbon at say 600 grit, should I finish it at say 1200 or just completely stop once I hit carbon?

User avatar
Mr.Hyde
Posts: 124
Joined: Fri Sep 05, 2008 1:03 am

by Mr.Hyde

If you hit the fibres, just have a look how the surface is. 600 should be okay.
You would not have the problem if you'd used the blades, then you get a smooth surface while removing all coatings.

gumgardner
Posts: 3553
Joined: Sat Jan 06, 2007 9:47 pm
Location: Pittsburgh

by gumgardner

Went with the blade. Wow! Nice tip. Gets it super smooth and doesn't take as long. I like the results so much I may decide to sand my SR11 shifters and derailleurs.

User avatar
Mr.Hyde
Posts: 124
Joined: Fri Sep 05, 2008 1:03 am

by Mr.Hyde

Trust me, I'm an engineer (or at least trying to become one :lol: ).


Edit: Concerning Shifters: http://lcblog.lotz-carbon.de/index.php? ... basteleien , also done with blades, like the WCS fork here: http://lcblog.lotz-carbon.de/index.php? ... basteleien.
I also have cleaned a frame and a bar, all works out fine, just the areas where some tubes come together isn't that good, you'll have to sand there in most cases.

JN2Wheels
Posts: 219
Joined: Sat May 09, 2009 3:03 am
Location: Maryland

by JN2Wheels

Anyone have a link to How-To using the blade method? Sanding has been discussed a bunch, but I have never heard of using a knife somehow. Gum, how'd your experience go? I need to do a zipp sl 145 stem and an old Giant aero seatpost... so, pretty complex forms.

by Weenie


Post Reply
  • Similar Topics
    Replies
    Views
    Last post