Help with CA buffing

[Rob77]

I really hope that someone here can tell me what I might be doing wrong. I've made several pens and they usually look pretty good up until the buffing stage, where I seem to mess up the CA finish. I end up with what looks like uneven CA with cloudy areas scattered throughout. So my initial guess is that I'm applying too much pressure when buffing but if I apply less, the buffing doesn't appear to do anything.

The process I've been using... I typically sand my blanks to 600, then MM to 12000. Then I apply medium CA (about 6 coats). Then using 400 and 600 sandpaper, I lightly sand in preparation for buffing. For my buffing, I've been using Tripoli and white diamond... Usually 1500 rpms on my lathe.

Any ideas would be greatly appreciated. It's been frustrating considering how much time I'm spending on these only to mess it up at the end. Thanks for any and all help!

 

[edstreet]

somewhat of a very odd way to go about things there.

Typically micromesh is for plastics while sandpaper is for general use.

The buffing compound you are using is for very fine delicate things. Not to take over from 400 grit sandpaper.

 

[bkersten]

Personally, the same as you, "I typically sand my blanks to 600, then MM to 12000. Then I apply medium CA (about 6 coats). " Then I just hit the blank with one pass of 4-0000 steel wool, and wipe off. Then I use Novus 3, Maguires polish, or one-step polish and polish up the CA. Use these same 3 on ones out of PR after sanding to 600, with no problems and a smooth shine/finish. Works for me.

 

[StuartCovey]

Here's what I do, this may help.
First I will sand it with 220, 400, and than 800. I will then apply my CA (usually 4-5 coats using accelerator). Usually the CA will have ridges from applying the CA, so I will use a skew and lightly take off just enough to smooth everything up. This also gives me a chance to be sure it is the right diameter and I didn't put too much CA on. Now I will start sanding with a 220 and than a 400. Now I can start my polishing which goes to 12'000 grit.

Hope this helps.

 

[lorbay]

Sounds like you a buffing through the CA. Remember CA does not like heat.
After I put on about 10 coats of CA on I light sand with 400 just there is no shine left on an then wet sand with all the MM pads looks like a mirror when done.
Lin

 

[MichaelD]

Cloudy is generally caused by too much accelerator, if you're using any, and too much heat. Too much heat is caused by too much pressure or too much speed or both. Remember, the heat could also be caused during the sanding phase after applying the CA.

 

[robutacion]

I really hope that someone here can tell me what I might be doing wrong. I've made several pens and they usually look pretty good up until the buffing stage, where I seem to mess up the CA finish. I end up with what looks like uneven CA with cloudy areas scattered throughout. So my initial guess is that I'm applying too much pressure when buffing but if I apply less, the buffing doesn't appear to do anything.

The process I've been using... I typically sand my blanks to 600, then MM to 12000. Then I apply medium CA (about 6 coats). Then using 400 and 600 sandpaper, I lightly sand in preparation for buffing. For my buffing, I've been using Tripoli and white diamond... Usually 1500 rpms on my lathe.

Any ideas would be greatly appreciated. It's been frustrating considering how much time I'm spending on these only to mess it up at the end. Thanks for any and all help!

Yeah, I think you have things a little mixed up and what is happening is you are sanding the CA off in areas just before you buff it, the buffing show the patches with the CA missing (dull).

You were already given a few different ways to do the job but here is how I do mine.

Finish the blanks sanding with grits 300 to 600, then apply 2 coats of thin CA and 4 to 8 coats of medium CA, half way through give it a very light sad with 400 to remove most of any ridges seen. Until now you used dry sanding now you are going to do the wet sanding, I use wet and dry 600-800-1000-1200-1500-2000 and 2500, wipe the blanks clean and then use Novus -2 as the polishing compound, this should give you a perfect finish...!

Good luck,
Cheers
George

 

[Dale Lynch]

Have to agree with Lorbay,probably over sanding is causing cloudiness.Try this:Sand the CA through 1500g 3M wet/dry to .001" oversize.Then buff with a medium buff and use plastic buffing compound.It shines up in less than a minute at 750rpm.

 

[Rob77]

Thank you very much for the replies and the suggestions. I'm looking forward to giving these a try.

 

[PeetyInMich]

I am doing it close to the way George (robutacion) is. Dry sand to 600 grit. Wipe with alcohol if it is an oily wood, several (typically 6-12) coats of CA applied with a folded paper towel (I don't use accelerator (because I don't have any)). Then wet sanding 600-1000-1500 - auto polish. I may do an intermediate sanding during CA application if I feel ridges forming. If it becomes "splotchy" or "mottled" instead of uniformly shiny, you have sanded though the CA.

 

[Pjohnson]

Each of us probably has our own method ... just slights variations. For me I follow the schedule below.

150, 220, 400, 600, 800, 1000, 1200
Wipe with denatured alcohol to remove dust
depending on blank - apply shellac/BLO mix ... gives a nice amber tone
6-12 coats of CA with accelerator
progress through all grits of MM with a wet sand
buff with two coats of HUT

I have had good luck, so far. not too plastic of a look with a nice shine.

 

[Teeball]

This is how I've done it for 6 months without a problem.
1. Dry sand with 180, 240, 320, 400, 600. ( still afraid to use the skew )
2. 3 coats of thin CA, 6 coats medium CA. Accelerator between each coat.
3. Micro mesh 1500 - 12,000. no more sanding.
4. buff away. DONE

When done the blanks look like glass.
Use CA only on wood blanks, no CA on acrylic.
Hope this helps, like was said before there are many ways work the blanks, this is just the way I started doing it . Good luck.

 

[Teeball]

Just as Pjohnson said use DNA ( denatured alcohol after dry sanding ), to clean off dust. Using the micro mesh is wet.

 

[StuartCovey]

Sounds like you a buffing through the CA. Remember CA does not like heat.
After I put on about 10 coats of CA on I light sand with 400 just there is no shine left on an then wet sand with all the MM pads looks like a mirror when done.
Lin

I'm agreeing. Big possibility you are taking off too much CA.
I've done this before

 

[mightymavkev]

My approach (used mostly on antler pens thus far):

sand 150, 220, 320, 400, 600
denatured alcohol

set lathe to slowest speed possible

2 coats thin CA with blue shop paper towel with accelerator between each

increase lathe speed a bit

400 abranet to balance the thin CA "sheen" - I try to dull it consistently using my shop overhead light reflection as a guide

decrease lathe speed to slowest speed again

6 coats med CA with blue shop paper towel with accelerator between each

NOTE: If I happen to notice one coat leaving swirls or ridges, I'll stop and sand again with 320/400/600 to smooth it out before applying more. With practice, you'll get pretty good at gliding on a smooth coat of med CA. I put one single drop on the paper towel first (for some reason, the properties of the blue shop paper towel do not cause the CA to cure quickly like regular paper towels). Then I use a single finger under the towel and move the CA on the blank back and forth 1 1/2 times with light pressure and consistent pace.

Once done with CA, if the initial application is really smooth to the touch, I'll just use 400 abranet to dull the finish consistently again. Otherwise, I may pull out the 320, 400, 600 to dull it but I don't sand super aggressive at this point.

increase the lathe speed by a couple hundred

wet sand with the full complement of MM pads. I do the first 3 MM grits in both directions each. For grits 4-9 I haven't noticed a need to do that.

increase the lathe speed some more. polish with HUT or CRAFTS plastic polish.

I use the 2 wheel pen buffing system and buff at medium speed.


I've been having excellent luck with this approach. I've found that 90% of any issues I have is because the lathe speed is too fast when applying the CA. Everytime I've tried to save time by keeping it a little faster, it's caused problems.

Hope this helps.

Kev

 

[Dave Turner]

With the hundreds of possible CA techniques out there, it's surprising how close everyone is in their methods, including me.

1. Dry sand blank to 400 grit. I always finish my sanding with the lathe turned off and sanding with the grain of the wood. I completely eliminate any circular sanding marks. I've never seen the need to go past 400 grit. If you can't see any sanding marks with your naked eye prior to CA, you certainly won't see them after your CA application. (The corollary is also true to some extent).

2. Clean off blank with denatured alcohol. Be especially thorough if it's an oily wood such as Cocobolo. Next a quick puff of air from the compressor to get rid of any lint or paper towel particles.

3. With the blank spinning at 200 rpm or slower, one coat of thin CA dripped directly on the blank with a folded paper towel (Bounty) under the blank used to spread the thin CA out for complete coverage. You can tell how avidly the CA soaks into the blank. If it's a lot, I'll do a second coat with the thin CA after spraying it with accelerator (I only use aerosol can accelerator - never the pump bottle).

4. Next I apply 10-12 coats of medium CA by placing a good sized drop of CA on a folded paper towel and and wiping it a few times across the blank, getting the layer as flat as I can. I alternate which side of the blank I start the initial wipe from. I use each corner of the folded paper towel so I get 4 coats with one piece. I use accelerator between each coat and proceed to the next coat immediately after spraying the accelerator.

5. I don't sand until I'm done applying all my coats. I then use dry 400 grit sandpaper at 350 to 400 rpm to knock the ridges off the CA surface until the entire surface is uniformly scuffed with no shiny "lines". I exercise care, particularly at the ends of the blank to make sure I don't sand too much CA away. I tried using 320 grit to speed this step up, but it was too aggressive. I always finish my sanding with the lathe stopped by going axially along the blank, eliminating any circular sanding marks.

6. I next square the ends of the blank using my sanding mill. This needs to be done since the CA builds up unevenly on the ends of the blank during application. If needed, I will score the CA with a box cutter at the point where it adheres to my 60 degree cones to be able to remove my blank without breaking the integrity of the CA surface at the ends of the blank. I always turn between centers. A little wax on the cones helps prevent the CA from sticking, but I usually forget to wipe it on before I start. When I square the ends of the blank, I try to leave a thin layer of CA on the ends. If this is not possible (rarely), I'll wipe the ends on a piece of paper towel with a little thin CA on it to coat the ends with CA.

7. Next I wet sand using MicroMesh pads at 350 to 400 rpm. I skip the brown 1500 grit pad, as this is too coarse, and start with the green 1800 grit pad. Don't get overly aggressive with the green pad, since it's still relatively easy to sand through the CA to bare wood. I usually stop, wipe the blank down and inspect it under magnification to make sure I've sanded out all 400 grit scratches (which are parallel to the axis of the blank as per step 5).

8. It's smooth sailing after the green MM pad. With the 3200 (tan) and 3600 grit (burgundy) pads, I usually put a micro bevel on the edges of the blank as part of my sanding process. This ensures there is no sharp rim that you can feel if the blank is a little proud of the adjacent component piece after assembly. I try to aim for a few thousandths of an inch proud. If you are the least bit shy, then you can feel the edge of the component.

9. Continue through the MM grits to 12000 (gray). For the coarser grits, I wipe down the blank with a paper towel after each grit to prevent a stray particle from leaving a scratch mark. You should now have a glassy shine to your blank. But it's not done yet.

10. Using a buffer and Canton Flannel wheels, I next polish the blank using Formax Ultra 6163 (Plastic-Glo P-22, this is white and from Caswell Plating) and finish with Formax Fine 6165 (P-112, this is beige colored). This completely eliminates the micro scratches left from the 12000 grit MicroMesh.

 

[medlongpens]

How long are you letting the CA dry? I was having the same problem with the finish getting cloudy after I was done polishing it. I read somewhere that the cloudiness was caused by the CA not being fully cured when you start to polish it, and some guys were letting it cure over night before touching it. I don't have the patients for that, so I let the CA cure for an hour or two after applying it before I started to polish it. I don't have the cloudiness problem anymore.

 

[Adillo303]

OK - My two cents, for what it is worth.

Note - Sanding is at 1,500 or less. If you finger gets hot, the wood is too hot. Extra bonus, the paper will not load up as much.

1) I sand 120 180 220 320 400 600 1,000
2) I take it off the lathe to the polishing station. There, I use my Beall wood buff. The third wheel it's dry, no wax. Here, I polish along the long axis of the blank to remove sanding scratches from the lathe. I end up with a pretty shinny blank.
3) Back to the lathe. 2 coats thin, 8 coats medium. No accelerator on the thin, every other coat on the medium. Never have the can close to the blank.
4) Back to the lathe. Sand paper 120 180 remove ridges. Lathe turning about 1,500.
5) Sand 220 320 400 600 1,000. Lathe still slow. Never fast when sanding plastic.
6) Off the lathe, make sure the ends of the blank are sealed with the thin. Nothing worse than having water seep in the end.
7) Back on the lathe. Wet sand with the 3 double side pads to 12,000. Dry with a rag while spinning.
8) Off the lathe, back to the polishing station. This time the BG Artforms two wheel buff with the blue compound.

I get a lot of compliments on my finish.

A lot of steps, but, they work for me.

 

[Chasper]

My approach is totally different.
1. Before CA sand to 600
2. 8-12 coats of thin CA, no accelerator
3. Immediately after CA before CA is fully cured, buff with White Diamond only, not too aggressive
Finished

 

[Animyzo]

I sand the blank to 600 grit.
Burnish it
10-15 coats of thin ca with accelerator between each coat (quick .25 second burst)
wet mm up to 12000

Lathe speed through the whole process -2600

The key is a light touch. The lighter the touch the finer the finish. This gives me a glass-like.

 

[maverickgal]

When we were doing art shows, we put a lifetime warranty on our pens - hardware, finish, everything... Rarely ever did we see any mechanical failure of any kind, nor hardware issues (after we switched over to using titanium parts that is), but we did see a fair amount of finish issues for a while. We quit using CA finishes and other commercially available ones, because we saw that the acidity of the owners hands wore the finish off after a few years, in certain areas of the pens. Would have been ok if it had ALL worn off the same, but it ended up splotchy from where their hands came in contact with the pen the most. And we found also that not all our customers had this problem - it seems to be that some folks are just more acidic than others, and those who weren't didn't have problems - but the ones that were highly acidic did. So we gave up and started having our various woods and antler PROFESSIONALLY stabilized with acrylic. NO finish needed from that point on, and it's pretty much idiot proof - I'm a living example of that!! Plus it's quicker, less things needed for a stunning finish, and I have pens that have been out there being used for 15 years with this finish method, and they look as good as the day they were made. Maybe this can help someone out...

However, I do have some old pens that were left in inventory that had the old finish on them, before we started using stabilized wood. Anyone have any ideas on how to freshen up a finish on an assembled pen without having to tear it apart?

Sharon