help for a newbie

[rreidiii]

I have turned several pens...when i say several its several not in the hundreds. anyway there are two things i have questions about.
One is that after turning several pens my blanks once turned are not perfectly round and seem a bit oval so they don't fit the pen kits perfectly. is this an issue with the mandrel and is it time to replace it?
Secondly, I've heard that turning between two centers is a better way to go and yeilds better results, is this true and if so where do i buy the bushings to do this. thanks in advance for any help!

 

[JimB]

Your mandrel may be bent or you could be over tightening it causing it to bend when turning. To know if it is bent take the mandrel (only the rod) and roll it on a flat surface such as your kitchen counter or a piece of glass or a mirror. You will be able to see if it is bent.

You may also have glue on the inside of the tube causing the bushing not to sit correctly.

Yes, you will get better results turning between centers. You can use regular bushings but many people prefer to buy better ones from vendors on here. I don't remember who sells them but there is another thread about this that was started a few days ago. Do a search and I am sure it will show up.

 

[JimB]

To TBC you will also need a 60 degree live center and dead center.

 

[Edgar]

When turning with a mandrel, you should be sure to tighten your blanks with the nut on the end, not with the tail stock. Add spacers if necessary to get your turnings up to middle of the threads so you have plenty of thread to tighten things up. Then just snug up the tail stock enough to spin the mandrel without it slipping. Over tightening the tail stock is the usual cause of what your seeing.

Better yet, get a mandrel saver. This is a tail stock tool that slides over the mandrel such that you don't use the nut on the end & the tail stock applies pressure to the turning without bending the rod.

Using a mandrel saver accomplishes the same thing as turning between centers. It takes a few seconds longer to dismount your blanks, but that's about it.

 

[magpens]

Yes, get a mandrel saver. . It is well worth the few dollars it costs. . PSI sells one.

If you want to dispense with the mandrel altogether, and turn between centers, then do some research. . Search this website for "TBC" and "Turning between centers".
You can get away without using bushings at all. . That saves some money and some headaches, if you have ever got your bushings mixed up.

You will need a decent set of digital readout calipers for about $30.

If you decide to go the TBC route, you will have to measure your kit parts carefully to get the right blank sizing when you turn.
You can look up the bushing sizes appropriate for your kit by using the tables referenced on the Home page of this website. You will need those numbers as you reference when you are turning, and you will need to frequently compare your measured blank size during turning with the numbers from the reference tables.

I do all my turning using the TBC method and I have gotten used to making frequent measurements. I now regard bushings as a pain.

 

[rreidiii]

Dang you guys are fast!!! I'm using a mandrel saver and I'm having this problem.
I just bought a couple of TBC bushings...along with a couple lazer inlay kits from one of the forum supporters a few minutes ago but where is a good place to buy a
Dead Center? I can see this can be an expensive hobby since i have just been giving my pens away to friends and family.
Anyway, am i possibly applying too much pressure from the tailstock?
any and all help is again greatly appreciated.

 

[rreidiii]

Yes, get a mandrel saver. . It is well worth the few dollars it costs. . PSI sells one.

If you want to dispense with the mandrel altogether, and turn between centers, then do some research. . Search this website for "TBC" and "Turning between centers".
You can get away without using bushings at all. . That saves some money and some headaches, if you have ever got your bushings mixed up.

You will need a decent set of digital readout calipers for about $30.

If you decide to go the TBC route, you will have to measure your kit parts carefully to get the right blank sizing when you turn.
You can look up the bushing sizes appropriate for your kit by using the tables referenced on the Home page of this website. You will need those numbers as you reference when you are turning, and you will need to frequently compare your measured blank size during turning with the numbers from the reference tables.

I do all my turning using the TBC method and I have gotten used to making frequent measurements. I now regard bushings as a pain.

Thanks Magpens, I already have some pretty good calipers as I reload for my other hobby which is extremely expensive so my better half tells me.
I'll do more research on the forum as I think I want to start to do TBC as a basic go to route since it just seems to me a better way of doing things albiet I could be wrong, and quite frequently am.
thanks for all the help and support!

 

[Edgar]

Check to make sure that your mandrel rod is not already bent as Jim suggested.

If the mandrel is ok, you may be applying a little too much turning pressure causing the mandrel to bend slightly - doesn't take much. If you're turning 2 blanks at a time, try just doing one. Doing them one at a time and keeping them close to the headstock can help.

 

[rreidiii]

Check to make sure that your mandrel rod is not already bent as Jim suggested.

If the mandrel is ok, you may be applying a little too much turning pressure causing the mandrel to bend slightly - doesn't take much. If you're turning 2 blanks at a time, try just doing one. Doing them one at a time and keeping them close to the headstock can help.

Thanks!

 

[Hawkdave]

I have been using a mandrel saver and over the few months I have been using it, I have noticed the thread on the mandrel is wearing down. This allows too much play and allows the mandrel to vibrate and throw the pen out of round.
I solved the issue by making another mandrel with only the thread for the morse taper and leaving the Mandrel saver end unthreaded. This has solved my problem nicely.

This was only happening when I turned a 2 part pen.

Dave.

 

[WriteON]

Secondly, I've heard that turning between two centers is a better way to go and yeilds better results, is this true and if so where do i buy the bushings to do this. thanks in advance for any help!

Avoid this for now. It is not a better way to travel. I'm sure it has advantages ....don't jump into it.
I'm not a TBC turner and most likely never will especially with pens. Anyway you'll learn by doing. I usually make every error/mistake at least one time.

 

[JimB]

I TBC using standard bushings for single barrel pens because it is quick and easy. When I make 2 barrel pens I usually use a mandrel because I like to see both barrels of the pen together.

Try both and see how you like it.

 

[GaryMGg]

Secondly, I've heard that turning between two centers is a better way to go and yeilds better results, is this true and if so where do i buy the bushings to do this. thanks in advance for any help!

Avoid this for now. It is not a better way to travel. I'm sure it has advantages ....don't jump into it.
I'm not a TBC turner and most likely never will especially with pens. Anyway you'll learn by doing. I usually make every error/mistake at least one time.

Please help me understand this:
If you're not a TBC turner and have never used this technique, how can you assert it is not a better way to travel???

 

[stonepecker]

As far as a "dead" center....... I thought the same thing and was looking for a 'cheaper' way. Someone (I think Skiprat) said why not make it out of wood? Take a piece of really hard wood and cut the shape to go into the head stock. On the other end just turn down to a point staying close to 60 degrees. (I think mine is closer to 55.)
I did this and it worked just wonderfully. The one tip I did get was everytime you remount the "dead center"...... Redress the point so it is centered again.
So far I have done 8 pens this way and the center I made is going strong......but I know I will have to make another sooner or later.

Good luck.

 

[WriteON]

Secondly, I've heard that turning between two centers is a better way to go and yeilds better results, is this true and if so where do i buy the bushings to do this. thanks in advance for any help!

Avoid this for now. It is not a better way to travel. I'm sure it has advantages ....don't jump into it.
I'm not a TBC turner and most likely never will especially with pens. Anyway you'll learn by doing. I usually make every error/mistake at least one time.

Please help me understand this:
If you're not a TBC turner and have never used this technique, how can you assert it is not a better way to travel???

Let's just say I'm content with bushings for pens. It works so I repeat it.
I have TBC for larger pieces and had them come off the lathe.

It's fair to say TBC is ok if that's what a turner has good success with.
If I thought it was better technique I would use it. It's the end result that counts ....not how we get there.
Better technique no. Alternative yes. I don't recommend it to a new turner. My advice is get real familiar with the lathe and then try it. I'm not looking to debate technique. The OP has to experiment. If they do TBC I hope they wear the proper face protection. (Should wear it anyway). Maybe I will try it someday. But for now I do not see any advantage. Plus I'm not a cut and measure, cut and measure kind of person.
If my first post seemed ignorant ...forgive me. Maybe TBC is better for some. Experiment and find out.