CA Finish Issue

[jimtsia]

Hi,
I hope someone can help me out. I am working through the learning curve on putting on a CA finish on my pens and other small projects and have a couple of questions on issues I am having.

1. I get through the finishing process and have a product that I am happy with until I try and get the blank off of the mandrel. Even though I am trying to be careful and not get the glue on the bushings I still do. When I try and remove the bushing from the blank I am chipping or lifting the glue off the blank in the process. I am very frustrated by this after all the time I have invested in the pen just to have this happen.

2. As a result of issue number one above I have several blanks that are just sitting waiting to be redone is there a better way then sanding the existing finish all the way off to correct the finish problem.

3. In the finishing process I am not using BLO is that part of this problem or does it matter.

4. I have read on various threads to "wax" the bushings. What is this what, type of wax do I use, how much of the bushing do I cover.

Thank you for any suggestions you may have on how to correct the problem. If the pens I am turning were just for me and not presents I would not be as concerned. But my deadline for getting them done is coming quickly.

Thank you,
Jim

 

[HamTurns]

Delrin bushings

Hi Jim -

I just started doing a little CA finishing and I found that Delrin bushings will take care of your #1 problem. I made a few sets for myself after buying a 3'x3/4" dia delrin rod from Graingers for about $7.

You can buy them already made if you want.

The CA won't glue to the delrin, so the problem goes away.

#3 I don't use BLO, only CA.

I hope this helps.

Tom

 

[Dan Masshardt]

$7 universal Delrin bushings from woodturningz or somewhere else. Will solve the majority of your problems.

There are other tips - use a skew to desperate the bushings wax them etc but the delrin is the easiest.

 

[Lenny]

Or ... finish between centers with no bushings.

 

[Jim Burr]

Or ... finish between centers with no bushings.

+1. All good suggestions. Some sticking with Delrin but a lot less than steel bushings. You can also make your own delrin bushings really easy!

 

[Displaced Canadian]

What I have done is After I do a coat of CA and it has dried I break the bushings loose from the blank. If you do this every coat or two it shouldn't chip the finish off the pen. If you forget you can use a sharp knife to carefully cut between the bushing and the blank. Doesn't really matter what wax you use, it helps a little but mot much. BLO works for some people, for me it just makes a mess.
As a side note I find that I get a better result letting the pen sit overnight between applying the CA and final sanding and finishing. The pen feels smoother and not as gummy.

 

[wouldentu2?]

One way is to use a razor blade and lay its sharp edge close to the tube end. Then rotate the lathe by hand making sure the blade stays away from but near the pen tube. Once around on each end and the bushing can be removed.

I you are applying 10 coats of CA do this every 5 coats.

The tapered Delrin bushings help a lot but will load up with CA if too many coats are applied. They will still prevent the CA from cracking on the tube.

 

[jimtsia]

Thank you for all the input!

I looked up the bushing that have been suggested and I will get some on order. In the mean time I will try the technique suggested on breaking the bushings off the pen blank after each coat of CA.

Now its back to turning, and getting better results!

 

[mrmartyking]

I use an Exacto knife to score the seam between the bushings and the finished product then gently break it off.

 

[GrahamColwell]

I used the XActo blade method as well. Then sand the end on 320 afterwards.
Now that I use ca/blo, I make sure that on my first coat of blo that I give the bushings a thin coat, and I haven't had the pen stick to the bushings yet.

 

[Jamesomac]

I typically use one coat of thin and 5 coats of medium CA. I use a small padded vice grips to gently rock the bushing off. There is always a bit of CA build-up extending over the end of the blank, but I place a small piece of 800 grit sandpaper on a flat surface and rub the blank around in a circle a few times. This removes the build-up. I have never had a problem with the CA cracking on the blank, but I fear if I used more coats, it might happen.

Rockler sells some plastic bushings that are supposed to prevent this sticking problem. Wonder if anyone has tried them.

 

[Ted iin Michigan]

Yet another input: I've had pretty good success by using a parting tool to remove the cured CA from the bushing. Then I sand and polish normally/ After that I've been putting the "nearly complete" body on the Beall wheels. Works pretty good and no additional purchases are necessary.

 

[Deadhead]

Apply the CA between centers w/ no bushings. Then turn a piece of wood to whatever morris taper you have and square the other end; you then glue a piece of 150 grit sand paper and the end, and put this piece in the head stock. In the tail stock use a drill chuck and apporprate transfer punch, slide the blank on the punch and and move into the the sandpaper and low RPM, flip it around and do the same. This will remove any glue CA build up on the ends. This is the method Ed at Exotic showed me; instead of turning a piece to fit th MT, I used a bottle stopper chuck from PSI and threaded a piece of 2 x 2 pine onto the chuck.

Ben

 

[Floridadude]

CA glue sticking to bushings

I put a coat of Johnson paste floor wax on my bushings and pen mandrel shaft and have no trouble getting them free. One coat of wax lasts a long time.

 

[lucky13]

The way I solve this problem is that after I apply my coats of CA and then wet sand I use a Parting tool at the very edge of the blank and part the CA off of the bushings, then after I take the blank off my mandrel I lightly sand the ends so there is no CA sticking over. Just have to be careful with the parting tool to not get over zealous and bung up the finish on the blank.

 

[walshjp17]

The tapered Delrin bushings help a lot but will load up with CA if too many coats are applied. They will still prevent the CA from cracking on the tube.

You can get rid of the CA build up by soaking the Delrin bushings in Acetone.

 

[bradh]

Hi,
==trim==
4. I have read on various threads to "wax" the bushings. What is this what, type of wax do I use, how much of the bushing do I cover.

Next time you at a craft show or farmers market, look out for someone selling honey. Ask them if they have bee's wax; they almost always do. These little wax sticks are great for many uses in wood turning, including waxing the mandrels and bushings.
In my area, the wax sticks usually sell for about $.50 each.

 

[HarleyCarl]

Woodcraft now sells cone shaped plastic bushings that slide onto the mandrel and will fit any size pen blank -- CA glue won't stick to them...

 

[Big blue 82]

I just got some delrin TBC (Turning Between Centers) from Johnny CNC / penturners products. I haven't applied CA with them yet but the fit up is great with the tubes / blanks and Delrin resists CA bonding very well in my experience.

 

[mdburn_em]

I never had success finishing with the bushings.

I tried many different waxes, tried cutting it with an Xacto knife, trimming with a parting tool. It worked sometimes and chipped other times. I got tired of it all.

I got a dead center and I apply my finishes with that.

 

[Dale Allen]

I've been doing some experimenting with polypropylene bushings.
CA cannot make a bond to it without first treating the surface.
I remembered that when I first tried to make a mold with this stuff for casting PR, the CA glue quickly let loose and the mold fell apart.
Below is a trial run using a blank that I could not get finished correctly.
The idea here is to make a poly spacer just a little larger then the blank size.
That way the CA buildup is outward from the blank and does not roll over the edge.
The poly came from a small cutting board sold at wallyworld.

I will complete this test and if it proves out I'll do a writeup on how to easily make them for either TBC or a mandrel.

 

[Dale Allen]

After a little more work the seam where the 2 piece meet is nearly invisible.
I think I'll make some more of these polypropylene bushings for more sizes.