Penturning

Hi Beth -

So the chip out that you are showing has a couple possible origins -

1) Not sure how you are squaring up your blanks before mounting them on the mandrel. If you use an end cutting tool, the chips may initially be caused by the squaring process. The squaring process cracks the wood and they chip out when you turn it. I suggest a squaring jig with a sander versus an end mill.

2) From the undulation of the wood along the blank leading to the bushings, I think you are cutting from center to the bushing, but you have undercut the wood as you are approaching the bushing, as it is proud of the blank prior to it. Unsupported wood will always be more subject to breakout than supported wood. Think spindle turning - you should always cut from thick to thin wood wherever possible. That gives you smoother cuts and helps prevent chipouts. Sharper tools make it easier.

3) If the chip goes all the way to the tube, you need to re-look at your gluing technique. Bad glue connections between the liner tube and the blank material normally start at the tube ends. Not sure of your glue, but if you are not using a 5 minute epoxy, you might want to consider it. Also, cocobolo is very oily, so you need to wash the wood (hole) with Denatured Alcohol prior to gluing to reduce the potential of glue failure from the oils.

You are experiencing normal failures and challenges - don't give up!

Kevin

THIS ISSUE HAS BEEN SOLVED!

Soaking in acetone worked. Thanks!

Hey guys. Thanks for the advice. I will need to get some acetone. As of now the project is set aside. I bought a new mandrel with a mandrel saver. I also bought the rubber bushings too.

Started a new pen from psi. I am turning a blank with cocobolo. It chipped terribly. Photos below.

on a good note I gave my lathe a good blowing out.

Hi Beth!

Guess you are continuing down the rabbit hole of penturning - BRAVO!

Not sure what type of chipping you are getting, but chipping on the ends versus in the middle of the blank points to two different things. End chipping is a typical symptom of gluing or trimming issues. Chipping in the middle of the blank is normally caused by too much pressure on the tool (cutting to fast) or a duller edge on the cutting tool. Both are painful, as you watch a nice kit slowly get destroyed in the process.

Cocobolo and many other supposedly hard woods require a lot of special care when turning to the depth of wood typical of a pen. You literally turn the blank to sometimes just a few thousands of an inch in depth, so the wood is put under tremendous stress and is more subject to damage than it would be in thicker turnings. People say penturning is easy, and a simple starting project for lathe turning - but turning a good pen, consistently, and dependably is a work of art. Don't be discouraged.

I haven't given one on one lessons on pen turning for a long time, as my new shop is relatively small, but if you get stuck, I can assist.  I am in Lavalette, so not sure if that is near you or not. Norm is also a really good instructor and might be closer to you.

Posted by: BETH Applegate on 11/28/2022 at 1:38 PM View/reply online Reply to forum at penturning@atlanticshorewoodturners.com Reply directly to BETH Applegate at themommyof2@msn.com If this message contains inappropriate content, you can report the message online

Hey guys. Thanks for all the advice. I will have to get some acetone. For now it is sitting next to the lathe. I bought a new mandrel with a mandrel saver and the plastic bushings to use when I apply the ca glue.

I am now having a different problem. Chipping on a bought blank from psi. Cocobolo. Maybe I need a workshop on the does and don'ts on pen turning. If anyone is willing to help, I would greatly appreciate it. I think I am just in too much of a hurry.

Hey guys. Thanks for all the advice. I will have to get some acetone. For now it is sitting next to the lathe. I bought a new mandrel with a mandrel saver and the plastic bushings to use when I apply the ca glue.

I am now having a different problem. Chipping on a bought blank from psi. Cocobolo. Maybe I need a workshop on the does and don'ts on pen turning. If anyone is willing to help, I would greatly appreciate it. I think I am just in too much of a hurry.

Hi Beth -

Just following up on your glued mandrel - did soaking it in acetone do the job? Its gonna take at least 24 hours of soak to get into the connections to soften it up, then your probably need a pair of pliers to twist it apart.

As a last ditch, if nothing works and you want to save the mandrel, just turn everything off the mandrel - nylon bushings, blank and tubes. I've never gotten it that bad but if that's where you are at, just turn it back so you can work things loose using the space where you turned it off to give you room. You will be easily able to turn through the brass tube and obviously the blank. If you get lucky, after turning out the center parts, you may be able to get the delrin bushing off. If you used the pen kit metal bushings, then I suggest drilling a piece of hardwood with a hole slightly larger than the mandrel shaft in it. Put the mandrel through the wood in the hole - then if you can lock the wood down in a vice or support it to allow you to pound on the wood with a hammer. You don't want to hit the mandrel, nor the mandrel ends - just the wood. CA is not a strong adhesive for mechanical force, so a little pounding on the wood pushing the bushings up or down on the mandrel should break them free. Once they get loose, take a sharpie and write on the wood piece " Don't do this again" and hang it over the lathe....lol.

Good luck! PS - if you have to buy new mandrels, I suggest buying adjustable mandrels versus a fixed one (Whiteside Pro Pen Mandrel #2 MT 844278090123 | eBay. The adjustable mandrel allows you to shorten the mandrel shaft with a collet on the taper end. Better still is to turn between centers (TBC)and eliminate the mandrel entirely. Advancing to TBC eliminates a lot of the wobble and off center issues brought about by bent mandrels, as well as eliminating any chance of gluing things together.

Best of luck!

Posted by: BETH Applegate on 11/23/2022 at 8:32 AM View/reply online Reply to forum at penturning@atlanticshorewoodturners.com Reply directly to BETH Applegate at themommyof2@msn.com If this message contains inappropriate content, you can report the message online

Yes well I tried that, but I think the bushing is glued to it too. I think I need to buy a new mandrel. 🤔 thanks Norman

Posted by: BETH Applegate on 11/23/2022 at 8:32 AM View/reply online Reply to forum at penturning@atlanticshorewoodturners.com Reply directly to BETH Applegate at themommyof2@msn.com If this message contains inappropriate content, you can report the message online

Yes well I tried that, but I think the bushing is glued to it too. I think I need to buy a new mandrel. 🤔 thanks Norman

Beth -

If the mandrel and pen body are glued to each other, try soaking the whole thing in a glass bowl filled with acetone. Acetone is a solvent to most CA glues, and it should break down the bond. It might take a few hours and possibly destroy the blank, but you have nothing to lose at this point. You can buy a can of acetone for a couple bucks in Homey Depot or your local hardware store in the paint department. Just be sure to use nitrile gloves when handling the acetone - skin is not a barrier to it, so it will be absorbed by your body and its not great for livers.

Happy Thanksgiving to all on the forum!

Kevin

Yes well I tried that, but I think the bushing is glued to it too. I think I need to buy a new mandrel. 🤔 thanks Norman

Posted by: BETH Applegate on 11/21/2022 at 11:58 AM View/reply online Reply to forum at penturning@atlanticshorewoodturners.com Reply directly to BETH Applegate at themommyof2@msn.com If this message contains inappropriate content, you can report the message online

Ok worked on a pen the other day and left it on the lathe...... now I can't move it. Pen from hell because, I broke it and then repaired it. The good news is that my repair still looks good. Any advi e on how to free it from the mandrel?

Ok worked on a pen the other day and left it on the lathe...... now I can't move it. Pen from hell because, I broke it and then repaired it. The good news is that my repair still looks good. Any advi e on how to free it from the mandrel?