Help,

[Scruffy]

I finished this pen and everything looked fine.

My wife went to take a photo of it and we saw this in the photo. This seems to have occurred after the pen set around for awhile.

OK I think something must have dried out or ???... but it look like the CA finish came away from the surface on the edge.

I did something to cause this. Any ideas or approaches to keep this from happening in the future.

 

[76winger]

First guess is you didn't have it covering the ends of the blank entirely. Possibly used the normal bushings and it pulled the CA away from the body material when you removed the glued-on bushings. At least that's what happened to me when I first started doing CA finishes.

If first started cutting the blank loose from the bushings with an EXacto knife to separate them more cleanly. Later going to some Eliminator bushings from JohnnyCNC which allowed me to get the CA down over the edge of the wood better, then sand it back down flat with the tube after polishing and removing from the lathe.

 

[76winger]

BTW, picture have a magical way of showing us stuff like this that we miss with the naked eye.

 

[Dan Masshardt]

Do you use anything to sand the end after applying the CA? I use the sanding mandrel sold by a member here or you can make one with the back of a pen mill or old mandrel.

I've not had this happen once since then. I also use universal synthetic (delrin) bushings for applying ca

 

[Lucky2]

Personally, I think that the end of the blank was square, and the CA or whatever it was filled in the void and allowed the end to be square. Cameras can be one of your worst enemies, it will pick up things that you will never notice on your own. What type or brand of glue did you use, did you use any accelerator? If you used CA, what consistancy was used thick, thin or med? How long was the blank glued up before you turned it? Speed and heat could have caused this also, what speed did you turn this with? And was there any heat on that end of the blank, as you finished it?
Len

 

[longbeard]

Do you wet sand the ca finish? was the ends sealed before you wet sanded?
Typically when this has happened to me, before i started sealing the ends with ca, water was doing that to me, OR the ends was not totally square and when the components was pressed in, then the finish would do that. Just last week i redone one tube 3 times, once on each end (was not square) the other i sanded thru the ca.
From the pic it looks like maybe the blank was not square and the ca over lapped the end of the blank, then when pressed together, it shoved the ca away from your blank.

 

[Scruffy]

See if I can provide all the requested info..

I think the bushing observation has a lot of merit. I will heed the advice. (johnnyCNC is out of the elimenators) so I'll have to use the Exacto Knife/Sanding approach suggested by Dave.

Is there another distributor of universal synthetic (delrin) bushings (Elimenator Bushings)?


My process, to touch all bases,

1. Sanded the tubes with 80 grit
2. Glued tubes into drilled out blanks wiht Med Stack Fast CA
3. Squared off the ends (using reamer/Squaring kit) after letting CA blanks/tubes sit for 15 minutes.
3.a Sanded Blanks to size
4. 2-3 coats of Thin Stick Fast CA (speed around 1000)
5. 5-7 coats of Thick Stick Fast CA (speed aroound 1000)
6. Used Stick Fast Accelerant between each coat.
7. Used paper towel. New section each coat. (Tore off last section)
8. Sanded starting at 320 dry sanding to get rid of ripples and bumps in CA. (around 1000-1200)
9. Damp (not wet) towel to wipe away 320 leavings
10 Cross sanded w 320
11. Damp (not wet) towel to wipe away 320 leavings
12. 400, 600, 800, 1500 2400 4000 &12,000 grit wet sanding ...Wipe away, cross sand, wipe away)(around 1000-1200)
13. Stick Fast CA Satin Friction Polish (Around 1000-1200)
14. Stick Fast CA High Gloss Friction Polish (around 1000-1200)
15. Buff & Assemble

 

[Dan Masshardt]

Woodturningz has some that I use. They are designed for mandrel use though.

 

[robutacion]

I finished this pen and everything looked fine.

My wife went to take a photo of it and we saw this in the photo. This seems to have occurred after the pen set around for awhile.

OK I think something must have dried out or ???... but it look like the CA finish came away from the surface on the edge.

I did something to cause this. Any ideas or approaches to keep this from happening in the future.

Well, this to me means that, the wood was slightly proud of the tube end, the CA got caught on the barrel edge and rolled in when you pressed it, not showing the problem straight away but, with a tight fit the slight excess wood over the brass end was compressed, taking the CA with is, some flexibility from the CA part as kept the join clean for a little while but overnight, the pressure exerted on that joint as let go slightly and all of a certain the CA pops out and straightens out, the problem is that, while the CA was compressed at that end it did separate slightly for the barrel end so, when the CA escapes from the pressed join, it shows how far the separation occur.

There is a big difference between having the CA coating overlap over the bushing and not have is cleaned up before assembly, is this case the problem would appear/be seen straight away as soon as pressed AND what I just explain so, and according to the OP claim, that option is out...!

PS: Now, how to resolve the issue and make sure the barrel is flash with the tube, there is no excess CA in there, is straight, sealed and the tube cleaned inside prior to assembly, that is another matter and one I'm sure you will get a few "pointers".

Cheers
George

Cheers
George

 

[ChrisN]

Well, this to me means that, the wood was slightly proud of the tube end, the CA got caught on the barrel edge and rolled in when you pressed it, not showing the problem straight away but, with a tight fit the slight excess wood over the brass end was compressed, taking the CA with is, some flexibility from the CA part as kept the join clean for a little while but overnight, the pressure exerted on that joint as let go slightly and all of a certain the CA pops out and straightens out, the problem is that, while the CA was compressed at that end it did separate slightly for the barrel end so, when the CA escapes from the pressed join, it shows how far the separation occur.

There is a big difference between having the CA coating overlap over the bushing and not have is cleaned up before assembly, is this case the problem would appear/be seen straight away as soon as pressed AND what I just explain so, and according to the OP claim, that option is out...!

PS: Now, how to resolve the issue and make sure the barrel is flash with the tube, there is no excess CA in there, is straight, sealed and the tube cleaned inside prior to assembly, that is another matter and one I'm sure you will get a few "pointers".

Cheers
George

Cheers
George

I just use my standard end mill to clean the excess CA off. I should really make and use a sanding mill, but I don't have any old cutters to convert.

 

[Wood Butcher]

Nothing to make, just turn the cutter around and put sandpaper on it.
WB

 

[mikec727]

I put sand paper on the drill press table put the pen on the pen mill extend and lock the quill and turn the blank by hand flip to do the other end .I have the sandpaper on a piece of hardwood ply.

 

[crabcreekind]

I just sand the end with 600 after I take it off the lathe. I apply my ca finish between centers. Probably done this with 200+ pens with no problem.

 

[HamTurns]

Is there another distributor of universal synthetic (delrin) bushings (Elimenator Bushings)?

Here is a post about those bushing for a bit more info; http://www.penturners.org/forum/f14/poly-bushings-ca-glue-109794/


I just started using a CA finish and very quickly recognized the need for these bushings. I made my own delrin bushings, they're easy and work great.

I bought a 3/4" dia x 3 foot long white Delrin rod from Griangers for $7.50, they had it in stock.

I finally got to use that scraper that came in my original tool kit that I'd never used before. It's a scraper with the tip shaped like this; /\ leaving a 60 degree cut on both sides.

I drilled a hole and put the delrin blank on my pen mandrel then just cut right in the middle of a 1.25" long blank, I cut right down to the mandrel with the scraper, parting off the pieces and leaving a nice 60 degree on both pieces. It took about 20 minutes to make these, including the drive over to Graingers.

About the same cost of ready made bushings, no shipping, and I have enough delrin rod left to make 28 more. :biggrin:

Tom

 

[ALexG]

In my case I found out that when you put a little wax on the bushing in order to avoid the CA glue to stick on it, is common when everything is mounted on the mandrel, to spread some of the wax on the end of the blank so the first coat of CA does not stick completely, so I have to wipe thoroughly the ends before applying any CA, then when finish I use a sharp skew to cut the extra CA that overlapped on the bushings

 

[MarkD]

I have had that problem before I started using Delrin finishing bushings. I expect the blank was glued to the bushing the what your seeing is a result of the blank breaking away from the bushing.

 

[plano_harry]

Alan, your process is fine, but a couple of additions can help avoid this, assuming the ends are square. If you can get the bushing eliminators, that will help a lot and may solve the problem. Until you get the eliminators, after sanding the bare wood, pull the tubes and put a drop of thin CA on a piece of glass or poly pen bag and just touch the tube ends to seal the end grain. Ream the inside of the tubes to remove any excess glue. Wax the metal bushings and put the tubes back on the lathe for your CA finish. Hopefully the wax will avoid having to cut the glue bond. After wet sanding and polishing, carefully sand the ends of the tubes square and flat by putting 400 grit on a smooth surface and making small circular motions.

Harry

 

[CrimsonKeel]

Had this same thing happen a few times when i first started. almost always it was because i had a small area of CA or wood that was not flush with the tube. so when pressed the cap or clamp on the other end puts pressure on just that small area that is sticking out and breaks it there.