Three questions on axle polishing

[ForgottenOne]

1. How fine is fine enough?
2. From one grit to the next how far is too far? (i.e. don't jump from 600 to 1600)
3. Which grit to start with ?(worried about thinning the axle too much.)

I have seen kits that have various sizes and wanted to get a feel for how far people take it.

The kit I can buy local (Autozone) has 1000, 1500, 2000, 2500. I have 400 and 600 at home.

Thoughts?

[sporty]

not fine enough, not even close.

you want sub micron. and atleast go to 1 micron.

A few years ago, I use to go to the 2500 you mention with automotive wet sand paper, then IO had found even 3000. but you can go finer allot finer.

[ForgottenOne]

All the polish kits I have run into stop about 2500 or 3000.

What about the other questions?

[Nate]

2) Always make as small jumps as possible. The grit jumps get larger as you get finer (ie 1000 ->1500 vs 100,120,150,180 etc) so there's no exact answer. If you're not removing scratches from the previous grit, you've gone to fast. You'll get better results sanding wet with oil or water, and removing swarf between grits.

3) I'll let someone with more derby axle specific experience chime in here. Our AWANA axles don't need much beyond polish.
My thought would be to file, then start with about 220 or whatever is the finest grit that removes your file's cut marks.



Hey, related question: what grit/micron is Mother's Mag aluminum polish? I used that this year in a dremel with good success (again, AWANA axles).

[sporty]

Mothers is somewhere between 2 micron and 1 micron.

Different websites seem to say different things. So thats why I gave that range. The billet lube seems to be at 1 micron.


If the axles are not looking like super bright chrome, then likely more work to be done.

forgotten one, there are many on-line pinewood derby vendors, selling kits that go to 25,000 to 50,000 grit and or 1 micron and sub micron.

Jewkes,winderby,max-v are just a few that come to mind. in no order of preference. just for reference.

Sporty

[68sportcoupe]

sorry but when you say 1-2 micron you lose me what would thet be in numerical grits(please dum it down for me)
After say 12,000 micromesh would you then use the mothers mag and rim polish or would the micromesh be beyound that.
thanks again

[gpraceman]

sorry but when you say 1-2 micron you lose me what would thet be in numerical grits(please dum it down for me)

Here's a conversion chart that may help.

A 1 micron particle size would be equivalent to 14,000 grit.

[sporty]

sorry but when you say 1-2 micron you lose me what would thet be in numerical grits(please dum it down for me)
After say 12,000 micromesh would you then use the mothers mag and rim polish or would the micromesh be beyound that.
thanks again

12,000 micro mesh is rated at 2 micron. However it is my opinion that as it wears, it goes to 1 micron, its fiber backed so tuffer than paper backed sandpaper.


I typically after the 12,000 micro mesh, go to diamon lapping film. 1 micron to .03 micron and .02 diamond polishing paiste ( this stuff is very very fine and I recommend using a breathing mask when using it.

This is just the stuff that I do. There are people that use brasso and other polishing paistes and processes.

To me as long as you get under sub-micron, then you are where you want to be.

Sporty

[DKO]

Here's an extemely informative discussion on polishing bores that can also be used with the axles compliments of sporty
http://www.derbytalk.com/viewtopic.php? ... ore+polish

[FatSebastian]

sorry but when you say 1-2 micron you lose me what would thet be in numerical grits(please dum it down for me)

Different grit sizes mean different things depending on the standard (FEPA v. CAMI). One could polish with CAMI 1000 and the follow up with P1200 and actually dull what was done with the 1000. Micromesh has its own sizings that are different yet again.

If you get all of your papers from a single source, you usually have a much better chance of having them all to the same standard. Just work your way up through the same brand and type and you are usually okay. We like Micro mesh because it lasts a long time, is relatively foolproof, and goes up to a rather fine polish (at least finer than most are willing to go in a kid's race).

[azgreg]

1. How fine is fine enough?

If you had a really small chin, you should be able to shave in them.

[sirslotalot1]

Just a quick thought. I once worked in the waste water industry for a company that filtered waste water. We had a product called a : Rotating Drum Vacuum Filter. We used DE, or diatamasious earth, swimming pool aggregate,very fine sand like material that was made millions of years ago when microscopic organizims died and fell to the bottom of the ocean floor which is now deserts. We could filter down to .05 micron. I asked: how small is .05 micron. Here was the answer I was given and made me understand just how small sub micron is: One of the hairs on your head is the diameter of 5.0 micron, .05 micron is one thenth of that. A smoke particle from a cigar of cigarette is 1.0 micron.

So you start to get some appreciation of just how small a sub micron particle is.

Hope this helps.

[stang68]

You can get kits at hobby stores that start at 3200 and go Thur 12000
Ebay is a good source for smaller then 12000,some vendors allow you to pick what sizes you need to make up a kit for a standard price.

[DKO]

I've found pkgs. of the micromesh at my local hobby store sold under the Revell brand name. I ordered some of the adhesive backed micromesh yesterday.

[Stan Pope]

One of the hairs on your head is the diameter of 5.0 micron, .05 micron is one thenth of that. ...

Check the math! One of the three numbers is wrong.