Finishing problems.

[TXTurner]

I started turning pens earlier this and so still consider myself a beginner. I'm having a finishing problem and am wondering if anyone can offer some advice.

I moved from wood to acrylics pretty quickly and have had some great results, even selling some pens to a local store. For finish on the acrylics, I had been doing great with a regimen of sandpaper (220,300, 400, 600), then micro mesh (to 12,000) then buffing (tripoli and white diamond) and then plastic polish.

I know some of this is overkill and/or going backwards and forwards, based on other posts I've read previously. But it worked.

On my last couple of pens, however, I'm still ending up with some very, very minor scratches that I can't seem to remove no matter how many times I go back to the buffing process. When I compare my latest pens to the very first acrylics I turned, the earlier ones gleam, even though they were made months ago.

On those first acrylic pens, I wasn't using the tripoli or WD. I would expect pens that I buffed to shine even more and, at least initially, the ones I buffed looked great.

Here's what I'm wondering:

1. Is it possible the Micro Mesh discs have worn out already?

2. The earlier acrylics (the ones that still gleam) were made with blanks purchased at Woodcraft. The later ones are celluloid blanks from CSUSA. Are the different materials part of this?

3. Do I need to rethink the finishing process that I've set up?

Any suggestions are welcome.

Thanks,

Mark

 

[maxwell_smart007]

Make sure your MM is clean, for starters...they last a long time, however...

What I found is that I was leaving residue on the blanks between grits...so the slurry I made with one grit was being rubbed in as I switched to the next grit...

What I do now is wipe the blank dry between MM grits, and that has gotten rid of most of my scratches...scratch remover does the rest...

Andrew

 

[maxwell_smart007]

Another idea is that your buffing wheels might be clogged...I find that brown tripoli ALWAYS leaves scratches on my blanks...not sure why....

Andrew

 

[Skye]

Three suggestions:

Cross sand between grits.

Wet sand.

Get rid of the disks and get some normal MM sheets.

 

[marcruby]

It takes a long time for MM to wear out, but it does clog. The trick is to put them in an old sock or nylon back an throw them in the washing machine now and then. That will also get rid of outsize particles. And never reuse sandpaper. It is possible that one of your buffing wheels has been polluted by another grit. I think they might survive washing, which is cheaper than replacing them.

One thing is to watch what is going on. Even use a magnifier if necessary. At each stage the surface should look uniform. If you can see individual deep scratches you need to go back and repeat from the step that caused the scratches.

Marc

 

[IPD_Mrs]

Another option that has not been looked at is what you are using to apply the plastic polish with. Depending on what you use it can leave scratches. Also if you use something like a t-shirt, never use an old one that has been washed with a powder detergent. This will cause scratches!!! Also if you are using a fabric of some sort pay attention the the weave as it will also leave scratches. If you want to freak yourself out any further buy a 10x loupe and look at your finish. Also the type of light you use when looking at the blank can make it look like there are scratches there even when they are not.

Mike

 

[TXTurner]

Effect of different light

That's an interesting suggestion - the idea that it can look different in different light.

I was going nuts last night because in daylight (there was still a good amount of it just outside my garage) the blanks looked beautiful. But when I looked at them under fluourescent light, I thought I was seeing small scratches.

The wife thought I was nuts.

Is it possible the fluorescent light is making it appear that I have scratches when I dont?

Mark

 

[IPD_Mrs]

Yes Fluorescent light will cause it to look like there are scratches when there are none. The best way is to take the blank to a room with incandescent lighting and use a magnifying glass to look at it. If you no longer see scratches then the lighting is causing it.

Mike

 

[TXTurner]

Any idea why the fluorescents do this?

Mark

 

[TXTurner]

Thanks for that input.

I've washed the MM with water and a toothbrush, but I'll try your suggestion the sock and the washer. And you're right - it can't hurt to try cleaning the buffing wheels either.

Mark

 

[redfishsc]

On my last couple of pens, however, I'm still ending up with some very, very minor scratches that I can't seem to remove no matter how many times I go back to the buffing process. When I compare my latest pens to the very first acrylics I turned, the earlier ones gleam, even though they were made months ago.

I don't know what color blanks the early ones were, but just food for thought: lighter color blanks will not show scratches nearly as much as a darker blank. I have some black PR that I dread making something out of because I know I'll grow a fu-man-chu before I'm done buffing out all the scratch marks.

On those first acrylic pens, I wasn't using the tripoli or WD. I would expect pens that I buffed to shine even more and, at least initially, the ones I buffed looked great.

Or it could be that those first pens were ones you REALLY wanted to come out right and you were REALLY patient with them, took your time, and got them right. After some success and a bit too much self esteem, you may have hurried the process a bit (and maybe even wore out your micromesh in a hurry).

Or not. But, I know my first few plastic pens turned out MARVELOUS and then I hit a rut with scratchy finishes also.

1. Is it possible the Micro Mesh discs have worn out already?

Yes. If you do not use water to wet-sand with micromesh, turn your lathe on SLOW and DON'T build up heat.

2. The earlier acrylics (the ones that still gleam) were made with blanks purchased at Woodcraft. The later ones are celluloid blanks from CSUSA. Are the different materials part of this?

No. Some of them are the exact same blank so far as I can tell. I've turned a good bit of both companies and they all behaved the same for me.

3. Do I need to rethink the finishing process that I've set up?

You should ALWAYS rethink your process when it starts to fail. And ALWAYS rethink it if you discover ways to do it more efficiently, or more accurately, or with higher quality, or more cost-effective. Expect a few bum ideas, expect a few great ideas.


My plastic schedule is this:

Dry sand blank on 500 RPM with silicone-carbide sandpaper (wet/dry paper) from 220 to 1500 (no micromesh). Buff with Tripoli and White Diamond. Remount on lathe and put the final insanity gloss on it with 3M's Finesse-It II.

Do I get the occasional flaw? Yes. Almost always due to me being in a hurry. Often I can buff it out on the Tripoli wheel (careful not to burn a skid mark on the plastic surface with heat!). Sometimes I have to re-sand 800 grit back up to 1500 and start over.

 

[TXTurner]

Thanks...

...for that reply and for taking the time to go through my note and offer the suggestions.

I appreciate all the thought that went into this and the other responses. I'll keep at it.

Mark

 

[itsme_timd]

Mark, I frequently turn pens with a friend and we noticed that my acrylics were coming out great and his - even after sanding, MM and polish - had scratches. Here are a few things we noted...

- He naturally had a lot "heavier" hand when sanding then I did. I use the MM pads with the foam and I tend to use just over the pressure necessary to hold the pads on the spinning blank but he tended to use quite a bit of pressure.
- We noted that there was a difference in the "bag of rags" that we used, some of them see to be pretty rough.
- The MM gets clogged quickly in my experience. Especially when using the small square pads. I clean mine by wetting them and rubbing 2 of them together then patting them dry with a towel.

Hope this is helpful!

Funny - I came to the finising forum because I'm having the same issue but with my wood pens, the quality of my finish seems to be worse than when I started! But, my acrylics look good.

 

[TXTurner]

Thanks...

...for that input, Tim.

I wonder if pressure may be to blame (too much of it on my part).

Good luck with the wood finishes.

Mark