Problem with CA Finish

[ChiTown56]

Hello everyone, I sure hope that I am posting this in the right area, if not would a mod please put me in the right area?

I live in the desert, Albuquerque, New Mexico where it gets very cold at this time of year at night time and is in about the 50's during the day. By cold at night I'm talking teens......

Anyways onto my issue; I am working with a pen that is using a African Blackwood blank, that is giving me fits! Here is my method for installing the CA process; Finish up the wood with 600, put 1 coat of Boiled Lindseed Oil on, wait 5 min, then put 1 coat of Medium CA, wait 5 minutes and due this until i get 5 coats of CA on and then let it dry up, so to speak? There in is where the problem pops up. In the past of doing this method, everything went well, the blank would dry shinney and I would start my sanding with 3600 and work my way up to 12,000 where it was nice and glossy! NOW? When it starts to dry it turns the finish Flat in spots, even rough in places and I have to back up the sanding to 2400 to get a smooth finish, but I run the risk of burning thru the CA, most times.....I just cannot figure out why my blank is turning flat and even rough in areas. Is this just a matter of the cold outside attacking my blank in the garage? Last night I tried a electric heater aimed at the blanks as they were on my lathe, but I still had a Little issue this am when I went out to check on it?

Any input would be greatly appreciated......

 

[CREID]

Wow. I put on my CA finish differently but that doesn't matter. Your getting your CA on so smooth that you start with MM 2400? Wish I could do that. I start at 400 grit sandpaper and then go to MM 1500 through 12000.

Curt

 

[ChiTown56]

Wow. I put on my CA finish differently but that doesn't matter. Your getting your CA on so smooth that you start with MM 2400? Wish I could do that. I start at 400 grit sandpaper and then go to MM 1500 through 12000.

Curt

Hi Curt, 2 things; 1) You live in Vancouver WA.? My Best Friend lives there and he is a turner.....PM me if you like and I'll put you two in touch. Mark is a Fantastic guy and one who has taught me a bunch! 2) I am so upset that I am using 2400 vs 3600 to start with, I am sorry, no pun intended.....But I really work at laying down that CA finish. I have found that a Good high powered lamp is essential to laying down the CA finish, so that you can see what you are doing.....PM me if you want to hear more?

 

[papaturner]

Wow. I put on my CA finish differently but that doesn't matter. Your getting your CA on so smooth that you start with MM 2400? Wish I could do that. I start at 400 grit sandpaper and then go to MM 1500 through 12000.

Curt

Hi Curt, 2 things; 1) You live in Vancouver WA.? My Best Friend lives there and he is a turner.....PM me if you like and I'll put you two in touch. Mark is a Fantastic guy and one who has taught me a bunch! 2) I am so upset that I am using 2400 vs 3600 to start with, I am sorry, no pun intended.....But I really work at laying down that CA finish. I have found that a Good high powered lamp is essential to laying down the CA finish, so that you can see what you are doing.....PM me if you want to hear more?

I`m sure we would all like to hear.
Thanks

 

[Dalecamino]

It sounds like you're sanding through the CA. Try 8 coats of medium with a light shot of accelerator every other coat. Sand lightly.

This is a subject that will draw lots of opinions that may or may not help you. I don't think the weather has anything to do with your problem. Some people store CA in their refrigerator.

Also, there are some decent videos on YouTube that may help. Good luck, I hope you work it out.

 

[Sabaharr]

I had this happening to me. No matter how much CA I put on when I MM it down it had irregular splotches of dull areas in the CA that would not polish. If that sounds like you r problem then here is what I found to cause it. TOO MUCH BLO. I had been using a paper towel wet with BLO to coat the blank with before applying the CA finish. It wasn't dripping off but it had more than needed to accent the grain of the wood. I started putting on just a drop at a time and rubbing it in with the lathe off. When it stopped showing on the wood I put on another drop on the towel until I had covered the whole blank. Then I turned the lathe on and buffed the blank with the paper towel to remove as much BLO as I could. Only after I had it as dry as I could get it did I start my CA finish, and never had another flat spot again on a blank. Hope that helps.

 

[Dalecamino]

Try it without BLO and, see how you like it. I stopped using it to speed things up a bit. Three coats of thin, eight coats of medium, sand and polish. Also, check for out of round. If you're using a mandrel, make sure the speed but isn't over tightened. That will cause the rod to bow. Just a thought.

 

[Rick_G]

Mike I had this and blamed it on the BLO. I stopped using it and start with 2 coats of thin CA. It figure this soaks into and seals the wood better than medium. I then add 6 layers of medium CA. I start my sanding with 1000 grit wet/dry paper and wet sand a little and inspect if I see any shiny spots I sand a little more in that area until they are gone, then jump to 2000 or 2500 wet/dry paper and wet sand a little then up to 12000 grit micromesh pads and then a plastic polish. As others have said dull spots may indicate you are sanding through the CA finish.

 

[Dave Turner]

It's amazing how many variations seem to work with CA application. I just give one quick coat of thin CA. Then about 10-12 coats of medium CA. No BLO. I use a quick spray of accelerator between every coat and don't wait between coats. I end up with a somewhat rough surface that I sand first with 320 grit then 400 grit dry sandpaper to bring the surface smooth and uniformly powder white. With each dry grit I sand first at 400-500 rpm then again along the long axis with the lathe off. Any residual darker spots (indicating un-sanded) get additional dry sanding. Finally I do wet sanding with micromesh starting with green and going through all the colors. I wipe off the blank with a piece of paper towel between each wet micromesh stage.

I find the CA layers add about 0.01 inch of increased diameter to my blank. Dry sanding will take that down about 0.002 to 0.003 inch. I like the blank to be a little proud of the component pieces so I only turn my bodies about 0.002 inch below my component measurement when allowing for CA thickness. When I do my wet sanding, I also include the corners of the blank starting with the tan micromesh. This eliminates any sharp tactile edge. Did I mention I do everything between centers?

 

[ChiTown56]

Mike I had this and blamed it on the BLO. I stopped using it and start with 2 coats of thin CA. It figure this soaks into and seals the wood better than medium. I then add 6 layers of medium CA. I start my sanding with 1000 grit wet/dry paper and wet sand a little and inspect if I see any shiny spots I sand a little more in that area until they are gone, then jump to 2000 or 2500 wet/dry paper and wet sand a little then up to 12000 grit micromesh pads and then a plastic polish. As others have said dull spots may indicate you are sanding through the CA finish.

Rick, please excuse my ignorance, but what is BLO? I've seen it mention before on this site.......

 

[Charlie_W]

Mike I had this and blamed it on the BLO. I stopped using it and start with 2 coats of thin CA. It figure this soaks into and seals the wood better than medium. I then add 6 layers of medium CA. I start my sanding with 1000 grit wet/dry paper and wet sand a little and inspect if I see any shiny spots I sand a little more in that area until they are gone, then jump to 2000 or 2500 wet/dry paper and wet sand a little then up to 12000 grit micromesh pads and then a plastic polish. As others have said dull spots may indicate you are sanding through the CA finish.

Rick, please excuse my ignorance, but what is BLO? I've seen it mention before on this site.......

That is boiled linseed oil....BLO.

 

[Sabaharr]

Mike I had this and blamed it on the BLO. I stopped using it and start with 2 coats of thin CA. It figure this soaks into and seals the wood better than medium. I then add 6 layers of medium CA. I start my sanding with 1000 grit wet/dry paper and wet sand a little and inspect if I see any shiny spots I sand a little more in that area until they are gone, then jump to 2000 or 2500 wet/dry paper and wet sand a little then up to 12000 grit micromesh pads and then a plastic polish. As others have said dull spots may indicate you are sanding through the CA finish.

Rick, please excuse my ignorance, but what is BLO? I've seen it mention before on this site.......

I see that you got your answer above but if you ever have another question like this and can't get an immediate answer there is a link in the library to the acronym list. Here it is. http://content.penturners.org/library/general_reference/Acronyms.pdf
This should be almost all of the ones used on this site. It has come in very handy for me. DAMHIKT.

 

[kruzzer]

I stopped using BLO a long time ago. I found out that every so often I would get flat spots on a given pen. I could never peg It down to one type of wood. Try replacing the BLO with a couple of coats of thin CA. I've never had one dull out on me since.
Just my $.02...

 

[Charlie_W]

First, I would try your exact process on a different piece of wood to rule out environmental factors.
Next, consider moisture content and or oiliness of different pieces of wood.

I wonder if when applying the initial coating of BLO, the cloth/applicator being used is imparting more BLO to the first area touched on the blank as the cloth is more saturated on initial contact than later as you are covering the rest of the blank.
Maybe the BLO needs to dry more before introducing CA.
Also, perhaps more time between coats is needed.

Without seeing you apply the CA, we don't know how much you are adding to the blank and how. Some folks tend to rub the CA out while spinning similar to a friction polish while others are building up the thickness of the CA and just apply a certain amount, spread it, and not continue to rub it out.

Remember that CA can get old and cause problems.

Good luck and keep us posted.

 

[Dale Allen]

When I first read through the OP, I was under the impression that BLO was used before every application of CA. Now I'm not sure that is what is being done. If it is, then I'd say quit!:biggrin:

As other have said, I quit using BLO a long time ago.
Too many issues with dull spots for me. I don't even use it to pop grain anymore because it just smells so bad!:smile-big:

 

[Dave Turner]

Remember that CA can get old and cause problems.

How true. I've noticed my medium CA getting thicker and thicker lately. It still works great, but requires a slightly different technique to apply than a fresh bottle.

Also, I've found that the brand and quality of spray on the accelerator I use probably makes the biggest difference out of anything. The finer the mist the better. I tried a spritzer bottle once with disastrous results. (I currently use NCF Quick Accelerator made by Satellite City and purchased at Woodcraft.)

 

[Sappheiros]

I saw a thread a while back discussing BLO use. They were saying if you use the BLO you could see cracking in the CA finish at a later time. Perhaps that has some connection with it.

 

[CREID]

It's amazing how many variations seem to work with CA application. I just give one quick coat of thin CA. Then about 10-12 coats of medium CA. No BLO. I use a quick spray of accelerator between every coat and don't wait between coats. I end up with a somewhat rough surface that I sand first with 320 grit then 400 grit dry sandpaper to bring the surface smooth and uniformly powder white. With each dry grit I sand first at 400-500 rpm then again along the long axis with the lathe off. Any residual darker spots (indicating un-sanded) get additional dry sanding. Finally I do wet sanding with micromesh starting with green and going through all the colors. I wipe off the blank with a piece of paper towel between each wet micromesh stage.

I find the CA layers add about 0.01 inch of increased diameter to my blank. Dry sanding will take that down about 0.002 to 0.003 inch. I like the blank to be a little proud of the component pieces so I only turn my bodies about 0.002 inch below my component measurement when allowing for CA thickness. When I do my wet sanding, I also include the corners of the blank starting with the tan micromesh. This eliminates any sharp tactile edge. Did I mention I do everything between centers?

This is pretty much what I do. The use of BLO can keep the application of CA a lot smoother, but to me it is way to much bother and harder to perfect (if CA finishing can ever be perfected) and I just gave up on it and spend a few seconds sanding before I go the MM.

Curt

 

[ChiTown56]

CA Finish Problem

Thanks Friends for all your asistance......

Yesterday I worked dillagently on this pen and watched like a hawk every single step of the way! Everything went well untill the temperature dropped hard outside, and my garage is uninsulated. Thus it it got cold during the last CA 5th coat, and that is where it all fell apart......The finish got rough in spots and became dull in spots. So I guess my assesment is; That the cold weather is creating my issues? To answer one of you folks question about how many coats of BLO i used? The answer is 1, and that was on the very 1st coat applied, before any CA was applied.

 

[TonyW]

If all was going well until the temperature dropped then perhaps it is a condensation problem, something I know well here in the UK! Although I am still getting to grips with CA as a finish, I have had problems with using it for gluing the brass tubes in, especially when I went through a phase of chilling everything down in the fridge to prevent tubes getting stuck part way into the blanks due to flash setting.

Tony Wells.

 

[allmaclean]

Thanks Friends for all your asistance......

Yesterday I worked dillagently on this pen and watched like a hawk every single step of the way! Everything went well untill the temperature dropped hard outside, and my garage is uninsulated. Thus it it got cold during the last CA 5th coat, and that is where it all fell apart......The finish got rough in spots and became dull in spots. So I guess my assesment is; That the cold weather is creating my issues? To answer one of you folks question about how many coats of BLO i used? The answer is 1, and that was on the very 1st coat applied, before any CA was applied.

Funny. I was blaming temperature also. Was finishing a couple of Olivewood blanks. Same process as I have been using for a while with decent results. Looked at the blanks in the cold light of day and saw striation marks circling the blank.
Only other change I had was going from Bob Smith CA (thin) to PSI brand.

Marks was on the CA and not the blank itself. Took the finish off o a clean blank and tried again with the same result. Frustrating.

Allan

 

[ChiTown56]

Thanks Friends for all your asistance......

Yesterday I worked dillagently on this pen and watched like a hawk every single step of the way! Everything went well untill the temperature dropped hard outside, and my garage is uninsulated. Thus it it got cold during the last CA 5th coat, and that is where it all fell apart......The finish got rough in spots and became dull in spots. So I guess my assesment is; That the cold weather is creating my issues? To answer one of you folks question about how many coats of BLO i used? The answer is 1, and that was on the very 1st coat applied, before any CA was applied.

Funny. I was blaming temperature also. Was finishing a couple of Olivewood blanks. Same process as I have been using for a while with decent results. Looked at the blanks in the cold light of day and saw striation marks circling the blank.
Only other change I had was going from Bob Smith CA (thin) to PSI brand.

Marks was on the CA and not the blank itself. Took the finish off o a clean blank and tried again with the same result. Frustrating.

Allan

Yes, Allan I've also taken the finish all the down and then started from Zero, so to speak and ended up with the same results 2-3 times. It IS very frustrating + I am losing a Good Sale. I have used my CA procedure all summer long without this happening and had good results! Until, the cold weather set in.....

 

[allmaclean]

Yes, Allan I've also taken the finish all the down and then started from Zero, so to speak and ended up with the same results 2-3 times. It IS very frustrating + I am losing a Good Sale. I have used my CA procedure all summer long without this happening and had good results! Until, the cold weather set in.....

I ended up going with Woodturners Finish, which I got from Exotic Blanks. It went on well and I was happy with the finished appearance. Not sure how long the finish will last compared to CA, but at least it is done.

 

[Sabaharr]

Might I then suggest the obvious and suggest to set a small heater under your finishing area.

 

[Dalecamino]

Don't lose a sale!! Set everything on your kitchen table :wink::biggrin:

 

[Philip E]

I am going to hijack this thread a bit, I hope you don't mind. I am having an issue with Ca not curing. Can't figure out why. the garage is at a 74 degree temp and 40% humidity and yet the CA stays tacky to the touch. I have been waiting over and hour and half for this stuff to cure. Any ideas anyone?

 

[CREID]

I am going to hijack this thread a bit, I hope you don't mind. I am having an issue with Ca not curing. Can't figure out why. the garage is at a 74 degree temp and 40% humidity and yet the CA stays tacky to the touch. I have been waiting over and hour and half for this stuff to cure. Any ideas anyone?

Is the Ca old?

Curt

 

[Philip E]

maybe a month or two.

 

[jttheclockman]

What brand of CA and what is the viscosity of it??? Is it thin, med or thick??? Put some on a piece of wax paper and see if it cures.

 

[robutacion]

maybe a month or two.

The problem is, how long did the store had it stored for...???

Old CA has proven to be the cause of that problem in 90% of times.

CA can also get contaminate, not an easy thing but, possible.

And as for the OP, to me, BLO is one cause, the second cause may be the natural oil that wood is known to have. Wipe the wood with acetone, let dry and try a few coats of thin CA, no medium, that sometimes produces good results...!

Cheers
George