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Forum topic by Fridgecritter posted 12-14-2013 11:08 PM 886 views 0 times favorited 17 replies Add to Favorites Watch
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Fridgecritter

170 posts in 864 days


12-14-2013 11:08 PM

Topic tags/keywords: question lathe turning finishing

Hello there,

I bought a few of the Bullet Pen kits from PSI, and they have been great. Unfortunately, five of my pens split on me, including one I already sold to a customer. I am going to replace his pen free of charge of course, but I wanted to see if anyone had any tips or pointers on how to reduce cracking and breaking. The tubes on these pens end up being around 1/8th of an inch thick.

The one in the photo is Gaboon Ebony. I have been finishing them with friction polish. I plan to use CA for future pens instead of the polish, and maybe make the body of the wood concave slightly outward, leaving more material on the tube.

Could it be that the brass tube is expanding and contracting with the weather? It’s 20 degrees outside and 70 degrees inside right now.

-- "Anyone can post a quote on the internet and attribute the quote to a famous person." -Abraham Lincoln


17 replies so far

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Hybridwoodworker

28 posts in 880 days


#1 posted 12-15-2013 01:38 AM

Were the blanks dry before you glued the tubes in?

BRuce

-- Life is hard, it is harder if you are stupid.

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Fridgecritter

170 posts in 864 days


#2 posted 12-15-2013 01:48 AM

I don’t have a moisture meter to test them, but I buy them from a supplier that lists them as kiln dried.

-- "Anyone can post a quote on the internet and attribute the quote to a famous person." -Abraham Lincoln

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Marcus

1080 posts in 767 days


#3 posted 12-15-2013 02:33 AM

Most of the ebony turning blanks I see arecwascsealed and not completely dry. That’s what this looks like to me, or at pleats where I would start.

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Marcus

1080 posts in 767 days


#4 posted 12-15-2013 02:35 AM

Also, how are you gluing the blanks to the tube. It’s odd to me to see the blanks separated from the tubes like that.

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Fridgecritter

170 posts in 864 days


#5 posted 12-15-2013 04:11 AM

I am using a gluing rod from a pen maker supply. I put the tube on the rod, glue it up with CA, then slide the blank over it. I am using a little Activator on the ends so it will slide off the rod easier.

-- "Anyone can post a quote on the internet and attribute the quote to a famous person." -Abraham Lincoln

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Ebro

34 posts in 484 days


#6 posted 12-15-2013 10:41 AM

I agree with Marcus. I’m concerned about the blanks coming off the tubes that cleanly. IMO, it’s either the CA glue you’re using or your technique. If you’re using thin CA glue definitely move up to medium or thick viscosity. Personally, I never cared for CA glue for gluing tubes, I always feel rushed with “instant” glue.

My process is to sand the tubes lightly with 100 grit sandpaper, add a little moisture to the inside of the blank and use Polyurethane glue making sure I twist the tube when inserting it to spread the glue evenly. As long as you get foamed glue on both ends, you can be sure you’re good to go.

I don’t think it’s a moisture issue with the wood. I’ve used everything from Ebony to firewood with great results.

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Marcus

1080 posts in 767 days


#7 posted 12-15-2013 11:34 AM

I switched from using CA to 5 minute epoxy after having a few tubes separate. It may have been bad glue, bad technique, or a combination of the two, but I have not had the same issue since switching to epoxy. I drill and glue up the blanks in the evening and then turn the next day, but have turned one as soon as 20 minutes after gluing without issue. I’m also a tube sander…I use 120 grit just because that’s what I have convenient.

Do you have the same issue with other woods or just ebony?

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Wildwood

1239 posts in 883 days


#8 posted 12-15-2013 12:23 PM

You are not first pen turner having trouble before or after assembly with Ebony. Turners over at IAP with experience recommend switching to African Blackwood.

I recommend switching to acrylic like this Jet Black blank.

http://www.pennstateind.com/store/AQP14X.html

To finish acrylics will need to wet sand and polish with micromesh. Never used MM pads listed in PSI catalog, I used MM Sheets. Optionally may wand bottle of One-Step plastic polish.

Lot of turners use auto lens cleaner or polishes vice 1-step or Hut’s plastic polish and they work.

May save little on pen making supplies blanks & finishing material at these PSI resellers. They also sell PSI kits, and less expensive kits.

http://www.woodnwhimsies.com/
http://www.woodturningz.com/

-- Bill

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Fridgecritter

170 posts in 864 days


#9 posted 12-15-2013 03:56 PM

I’m going to try the epoxy and see how that works. I agree that they came off a little too cleanly. The brass tubes come already roughed from PSI.

-- "Anyone can post a quote on the internet and attribute the quote to a famous person." -Abraham Lincoln

View Bill7255's profile

Bill7255

201 posts in 1033 days


#10 posted 12-16-2013 12:13 PM

I switched to epoxy very early on. I was initially doing friction polish, however doing friction polish you put heat into the pen and glue. I had some wood blanks separate from the tube. I attributed it to heat and not roughing the tube to remove the oxidation completely. Even though tubes may be “rough” from the vendor it is a good idea to rough them just prior to assembly as brass will oxidize. I now do CA finish for all my pens.

-- Bill R

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Marcus

1080 posts in 767 days


#11 posted 12-16-2013 12:40 PM

Does anyone use PVA glue to glue the blanks to the tubes? I would think it would hold well, but just worry that has it expands, it would just come out the ends vs sealing tight between the blank and tube.

View William's profile (online now)

William

9271 posts in 1590 days


#12 posted 12-16-2013 12:47 PM

The already roughed tubes still have residue on them. If you look, they are roughed with a smooth motion from a machine. Use rough grit (I use 80) and rough the tubes good.
Next I use CA glue to put the tubes in. I use a plastic nozzle that came with an automotive tube of silicone. The tubes do not stick to it and it works for me. I put three generous lines of thick CA glue on the tube. Then I quickly insert the tube into my blank with a twisting motion. This spreads the glue all around the tube.
Lastly, on pens such as these, you are correct that the wood is mighty thin over the tube. I leave a slight bulge on my bolt actions. I do not like leaving too much though. Too much and it looks like a bullet with a beer belly.

All this being said, I’ve never worked with ebony. I have used other dark woods like ziricote and Texas ebony. They did not give me any issues. As a matter of fact, I dropped a pen made of Texas ebony on concrete. It did not damage the pen itself. It did mar the finish where it hit the hard concrete. I gave it to my son. He still uses it at work.

-- http://wddsrfinewoodworks.blogspot.com/

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Fridgecritter

170 posts in 864 days


#13 posted 12-16-2013 03:45 PM

Good info William. I will rough the tubes a bit more. Thanks a ton.

-- "Anyone can post a quote on the internet and attribute the quote to a famous person." -Abraham Lincoln

View Wildwood's profile

Wildwood

1239 posts in 883 days


#14 posted 12-16-2013 11:03 PM

Ebony woods considered oily and dense. From reading post over at IAP, know heat not good for Ebony. See where Gaboon Ebony aslo called African blackwood.

CA or Gorilla glues should work. Doubt CA is the cause of the blank splitting.

A postage scale to weigh pen blanks best method to measure MC of a pen blank. You weigh them until they stop losing weight. So let blanks hang out until they reach EMC (stop losing weight).

Ebony woods listed as dense woods, so would wet sand & polish with micromesh. Might use little fine rubbing compound to remove and tiny scratches, after wet sanding with 1500, 1800, 2400, than start polishing with 3200 thru 12,000. Add a drop or two of liquid dishwashing soap to my water. Wipe down the blank with a paper towel before moving to next grit.

This is why recommended acrylics, can turn when you get them!

-- Bill

View Elizabeth's profile

Elizabeth

811 posts in 1891 days


#15 posted 12-16-2013 11:23 PM

Marcus, I use Gorilla Glue which I believe is PVA. It does expand out past the ends of the tubes but I have one of those barrel trimmers – chuck it into a hand drill and it cleans up the excess glue and levels out the edge of the blank with the end of the tube.

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