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Chris Parker
11th August 2004, 08:15 AM
I have just been giving pen making ago for the first time. I have some questions:

1. I can't seem to get the brass tubes from spinning on the mandrel. I had to turn/tightent the tailstock up so hard that it does not seem right (and is starting to buckle the brass at the drive centre end).

2. Does one tunr with the pen centre ring in place. If so how do you ensure that it does not get damaged (sanded).

3. When in the process do I use the levelling tool to shape the brass and wood at the end?

Thanks in advance.

Chris

macca2
11th August 2004, 11:42 AM
Chris,
No you should not turn the pen with the centre ring in place as this will indeed get damaged. With the mandrel I have you butt up the 2 halves together with no spacer. There are mandrels that have ferrels that act as guides for the size of the turned pen.

Before you mount the blanks on the mandrel you must square the ends of the wood and the brass insert (that you have glued into the blanks), (I use super glue) so as they are both flush, or you will get damage to either depending which over hangs the other. If you do this you should not need to over tighten the tail stock to hold blanks firmly for turning.

Good luck

Macca

DanP
11th August 2004, 11:55 AM
Chris,

I have the mandrel with the knurled brass nut on the end, which I never do up any tighter than finger tight and I never have a problem. Get yoursef a pen mill to square up the ends.

Is the brass tube spinning on the mandrel or is the blank spinning on the tube? If the latter, give the tubes a quick rub with sandpaper before gluing in. Use GOOD QUALITY Superglue, not the rubbish you get at the supermarket. I use the one in the yellow bottle from Carbatec.

Dan

Chris Parker
11th August 2004, 12:14 PM
Thanks Dan and Macca,

I am unsure how the pen mill helps. If I am using wood stock that is about 20mm square the pen mill will only sqaure up a circle of diametre 12mm. Because this squared up bit is now recessed into the stock, it will not be the squared bit that is butting up against the square bit in the centre. Does that make sense?

How long do you wait for the super glue to dry (I think I may have rushed it).

Thanks

Chris

Salty
11th August 2004, 12:33 PM
because the diameter of a pen is so small you need to have the lathe wound up to the highest speed and use the sharpest of tools ( mainly a big skew) and take light cuts. I am a learner too but I have found that you need to use the appropriate sized bush between the blanks which puts pressure on the brass and the milled wood as you wind up the mandrel nut. :) Hope this is of use from someone who is still low on the learning curve:D

PAH1
11th August 2004, 12:40 PM
The bushing in the centre is to allow for the recessed nature of a milled blank ie the overhang. If you are careful you do not damage the bush at all and they act as depth gauges for the final size. If you are cutting your own pen blanks you can make them a fair bit smaller, I have done it down to 10mm but that is getting pretty tight if the drill bit wanders around. I use araldite to glue the tubes in, takes more time to set but you do not have to worry about what happens with cyanacrylate type resins.

If you want to take out the central bush then you will need to sand all of the excessoff in the centre so that the two pieces meet flush.

Hope that helps

Peter

KevM
11th August 2004, 02:15 PM
Chris,
Your mandrel should have 3 bushes, place one at each end and one between the blanks. These bushes fit inside the hole cut by the pen mill and you use them as a guide for the size to turn the timber down to.

I used to use superglue for gluing in the brass tubes but found it tended to grab sometimes before I had the tube fully inserted and as a result lost some really nice blanks. I now use a Selleys 2 pack and have not had a problem with the tubes rotating inside the blank. I always leave my blanks for at least 24 hours before using the pen mill to allow the glue to dry. It does not hurt to rough up the outside of your brass sleeves prior to gluing with some 180 grit paper.

The pen centre ring does not go near the blanks until assembly.

What brass and wood at the end are you wanting to shape?

regards

Kev M

macca2
12th August 2004, 12:29 PM
The mandrel I have has no centre bush and the 2 halves of the blank just butt up together. If the milled ends have 12mm circle recessed slightly this no problem as as you turn down to finished size the waste goes and you get down to within this recess. You will have to adjust the tail stock as you turn away the waste.
Hope this makes sence.

Macca

DanP
12th August 2004, 01:56 PM
Macca,

Sounds like a pain in the ar5e. Do yourself a favour. Get one of these.

Mandrel @ carbatec (http://www.carbatecvic.com.au/shop/customer/search.php?substring=mandrel)

Dan

KevM
12th August 2004, 02:19 PM
Hello Macca,
I agree with Dan, if you have enough room on your mandrel, buy yourself a set of 7mm bushes available here http://store.yahoo.com/gpwoodturning/penbushes.html for $6.00 for a set of 3.

You will find it much less hassle when you use a centre bush as well.

Regards

Kev M

DanP
12th August 2004, 02:42 PM
This mandrel is a 1/4 inch diameter. Bushes are not required unless you are turning pens with click mechanisms. It comes with three spacers to separate the blanks. While your at it, get a pen mill as well.

Dan

macca2
12th August 2004, 05:51 PM
I use the Cornuta mandrel from Timbecon. No bushes and no hassels

Macca

Toggy
15th August 2004, 10:25 PM
I use a mandrel like the one Dan posted. Works great; but the spacers have worn down considerably. Also have found that at times it is easy to touch the brass nut with a roughing gouge.

Today I had to fire up the metal lathe; so used a veeery tough bit of old stainless steel shafting to make new spacers. This time I made two of them 5mm longer for on the ends to give that bit more clearance. Work just fine.


Ken

gatiep
16th August 2004, 01:00 AM
Ken

The suppliers all carry some sleeves wich are used to put into the uprights of book cases, where little stubbs get pushed in to adjust the shelf heights. These are about $2-00 for 20 and they fit well as replacement spacers. They are brass and could discolor the light timbers depending on the polish used.

smidsy
16th August 2004, 01:33 AM
Ken,
Another option would be to use some brass tube as a spacer - if you're like me and managed to kill a mechanism (there's a reason they supply assembly instructions) you probably have a spare tube, failing that the brass is a standard size and available from a hardware store.
As for the brass nut, the mandrel would be a standard thread so you can just use a nut if you like, although use a washer as well to make doubly sure that the space can't slip over.
Cheers
Paul

gatiep
16th August 2004, 11:18 AM
The brass thumb nut has a weird medium course metric thread, not the same as the standard 6 mm thread. So I was told over the weekend anyway.

gatiep
16th August 2004, 11:21 AM
And this is just to start the week with 500 posts.

smidsy
16th August 2004, 01:11 PM
Hei Joe,
It's scarey for me, I've only been around since May and this is post #168 - teaching the cat to type was the best thing I ever did.
In terms of the nut, I had assumed that it was a standard thread. I might call in at Searle on my travels and see if they can ID the thread type and sell me a few nuts.

Chris, if you go to a specialist fastener place they should have some nuts that will fit, or you could use an extra spacer at the end to get the brass nut futher away from the work.
In terms of turning the pens, you should do what seems right for you. I start with the middle spacer in for initial turning, but I then remove it and have the blanks together so I can get a good uniform joint on the pieces - I've been told by my wood turning group instructor that this is wrong but it works for me.
Cheers
Paul

DanP
16th August 2004, 02:47 PM
Smidsy,

I turn the blanks together when turning timber pens, separate on acrylic. Dont know why, just prefer it that way.

Dan

DanP
16th August 2004, 03:16 PM
This is my pen. I've sold a few of these to mates.



Dan

smidsy
16th August 2004, 03:48 PM
Hei Dan that's a real nice pen.
Joe, I'm afraid you were given dud advice on the thread mate. I just took my mandrel to Searle fasteners and it is a standard 1/4 UNF thread.
Cheers
Paul

gatiep
17th August 2004, 12:02 AM
Paul,
Thanks for that mate. Yeah it was a guy at the ww show that had a chat to me and told me that. That is the reason I said " I've been told" as I have come accross quite a few wise guys in my life. Once I have checked a thing out or do it myself, then I'm happy to state it as fact. Good one, now we all know what that brass nut is, I may even turn a few knurled ones up in brass on my metal lathe. If I do, I'll let you have one when I see you. I know there is someone at the club ( can't remember who ) who lost his, besides you.

smidsy
17th August 2004, 12:19 AM
Hei Joe,
I still have the brass knob for mine, but I got some standard nuts because I too have hit the brass knob from time to time with the chisel.
Now that we know what the thread is another option would be some standard wing nuts from Bunnies with some of the wing trimmed off.
Cheers
Paul

Ruffy
8th September 2004, 11:03 AM
One of the blokes at my local Carba-tec store put me onto using Bondcrete for fitting of the brass tubes, had a lot more success at doing this rather than using superglue.