Need some info

[penmanship]

Hi gang ~ was just reading a post from Mike in Nanimo, and he mentioned turning some pens "between centers using the regular bushings". What is the process of turning between centers?

Is this a better way of doing things, of just another way of doing things?
Any and all assistance is appreciated.

Thanks a bunch,
Tim

[Mike in Nanaimo]

I PREFER IT AS IT IS VIBRATION FREE, AND TRUE ROUND. You need a 60 live centre and a 6o degree dead center.
http://www.islandchimes.ca/Ebay%20Grapics/Pen%20Between%20Centers.JPG

[jaywood1207]

I can't believe you would post such a picture Mike. I've never seen your shop so messy. :D:p

[penmanship]

So......by the looks of it, this would eliminate the need for a mandrel, yes? You can only do one barrell at a time, but you can do "A" & "B" size bushings using this method?

This looks great, I'm going to have to try this.

Thanks for the info,
Tim

[Rick Gibson]

If you don't have the 60 deg live and dead centers Tim you can get them at Busy Bee tools. Look in the metal lathe section for the morse taper on your lathe. Their server appears to be down right now or I would post the link. If I remember I'll check later today.

[Mike in Nanaimo]

I know Jamie, and that is after 6 pens. Hope to get out the next 3 days and make more mess, cause I know after Thurs I'm down again for the week.

[Mike in Nanaimo]

Tim, About the only pen s you can't do are ones like slims where the bushings only butt up to the wood.

[Rick Gibson]

You can even do slims but have to be real careful not to apply to much pressure or you spread the tubes and crack the wood. With slims you don't use the bushings. I've done it and ruined a few as well.

[gwilki]

If you really want to get precise, get a 60 degree countersink and use it on the outsides of the bushings. Then your live and dead centres will perfectly center themselves, and you get more driving surface. I've done all my bushings this way.

[bohdon]

I don't understand why you need a 60* live & dead center. The ends of the bushings are not 60*.

What I'm saying is any live & dead center should work.

Rick I don't know if it's possible but perhaps you could put a short piece of rod inside the blank just long enough to hold the bushings in the end but not interfere with the centers... depends on which bushing you have for the slim, I have some that are 1" and some that are about 3/8" long.

Just my thoughts.

[Rick Gibson]

Bob

The reason for the 60 deg. is the indentation on the end of the mandrel rods is 60 deg. Using the standard live center that comes with a wood lathe you will eventually wear the tip off the center. If you buy bushings designed to work between centers they have 60 deg indents for the centers. The dead center for MT2 lathes are under $10

http://busybeetools.ca/cgi-bin/product10?&NMCLASS=00164&NSBCLASS=00157&NETID=1717230218081764739

What is really comes down to is when turning between centers you are dealing with metal to metal contact and you want as much surface area contact as possible to prevent slipping and wearing things out.

I thought of a short rod but I have the shorter bushings for the slims so it would not leave much to keep things from tipping. I just cut down a mandrel rod so it was just long enough and use that in my drill chuck.

If you really want to get precise, get a 60 degree countersink
Hadn't thought of that Grant I was just going to grind down one of my larger drill bits to a 60 deg. angle and go from there. This would likely be more accurate. All I have to do now is find a souce for the countersink.

[gwilki]

Rick
I can't help you much. I got mine from Legere Industrial here in Ottawa.

Most countersinks are 82 degree, so you need to find a specialty place to get them.

[bohdon]

Bob

The reason for the 60 deg. is the indentation on the end of the mandrel rods is 60 deg. Using the standard live center that comes with a wood lathe you will eventually wear the tip off the center. If you buy bushings designed to work between centers they have 60 deg indents for the centers. The dead center for MT2 lathes are under $10

http://busybeetools.ca/cgi-bin/product10?&NMCLASS=00164&NSBCLASS=00157&NETID=1717230218081764739

What is really comes down to is when turning between centers you are dealing with metal to metal contact and you want as much surface area contact as possible to prevent slipping and wearing things out.


Yes I realize that the end of the mandrel is 60* Rick but my point was that you are not using a mandrel (I think) you are just putting the center into the end of a standard bushing which is cut off at 90* with a slight round over on the inside. If it's not 60* then there's no reason you would need a 60* center. If you countersink to 82* then a 82* center would make more sense.

You can find a 60* counterbore or center bit at a metalworking supply shop.

[Louis]

Most people doing mandrel-less turning are using custom made bushings that have a 60 degrees end.

[bohdon]

But Louis you are missing my point, we are talking about using the standard bushing that we buy from the people we buy our kits from.

The standard bushings are not drilled out to 60* on the end.

What I'm trying to get at here is this. I'm guessing most have 1 60* live center, but they also have other live centers that are not 60*. So if you are turning between centers using standard bushing, as someone else had mentioned you will be wearing out that 60* center because it does not match the standard bushing end.

If you wear out the end of your 60* center you will have to buy a new one if you want to use your mandrel in the future.

My point is why wear out your 60* center when you have a center sitting on the side that hardly ever gets used, wear the other one out then you won't have to buy a new one. The other center you probably use just straight on wood (bowl) so a little wear on the end of that one is not gonna hurt anything & you will not have to buy a new 60* center.

My 60* live center cost me $135, yes I realize now that they can be had for cheaper but still why waist a good live center when you have other options.

[edblysard]

Maybe I missed something here, but why not get a live center with replacable tips?
Almost all mail order places, WoodCraft, Penn Industires, Hutt and CraftUSA have them, for something like $15.00 American, number 1 and number two morse tapers.
Little higher quuality one run about $59.00.
Tips run about $3.50 each....
http://www.woodcraft.com/family.aspx?familyid=4436

The Jet, Rikon and Delta mini and midi lathes come with live centers which all have replacable tips...

As for countersinks...a number 6 screw counter sink is also 60 degrees...

[slivermetimber]

As I understand it if we're turning between centers then a mandrel is not used & the center's "point" fits into the end(s) of the bushing(s), so....it really doesn't matter what angle the centers are at; 60, 80, 90 etc.... (within reason).
The only need for a 60 degree center is when using a mandrel to prevent the tip breaking off in the mandrel "tailstock end".
I agree with the statement that the end of standard bushing may be "countersunk" (ie the inside bore of the bushing is chamfered internally) to the same angle as its mating center as this will provide a larger surface for the center to bear against (more friction) & more stable.

[Mike in Nanaimo]

I have no problem at all with slippage, so there is no wear on the bushings or the centers. Use sharp tools and light cuts.
.

[gwilki]

Bob
You're right, of course. If you (not YOU personally) are going to use standard bushings, it doesn't matter what live centre you use.

If using standard bushings, and not countersinking them, you need to be careful when you tighten the tail stock. It is easily possible to have the dead centre on the headstock and the live centre on the tailstock off kilter a bit. They can bind on the 90 degree bore on the bushings, and throw the blank off. This can happen, regardless the angle on the centres. That is what really decided me on countersinking my bushings. They can still be used on a mandrel, but I have the option to use them between centres.

[Mike in Nanaimo]

I think the hardest thing is to find a 60 degree bit. Especiallly here on the Island.

[Louis]

But Louis you are missing my point, we are talking about using the standard bushing that we buy from the people we buy our kits from.

The standard bushings are not drilled out to 60* on the end.

No I got that part, maybe I'm just not clear. :)

If you (not YOU personally) are going to use standard bushings, it doesn't matter what live centre you use.

Agreed.

[edblysard]

Mike,


http://www.basstool.com/PDF/Binder2.pdf
Any machine shop should have these fairly cheap...
You would need a #4 to countersink a 1/4" bushing...$6.94 and they last forever.
1-800-442-0042...see if they can mail you one...
I buy all my machine supplies from them, they are local for me, inexpensive to boot...check out the drill bit selection.
http://www.basstool.com/PDF/Binder1.pdf

[Mike in Nanaimo]

Thanks edblysard. I will keep thet site. I will have to see what else they got so I can make it worthwhile for shipping.

[johnnycnc]

You can also turn 7mm tubed pens between
centers,using these,they are 60° specific.
Thought I'd share these,as regular 7mm bushings just
won't work for between centers.
I think a few of the members here have some of these.
I am the guy who makes the "custom" bushings.
You could make your own if you're handy with metalworking.
Pictures are of 7mm slimline set.
397

398

[Mike in Nanaimo]

Good to see you here Johnny. I am no associated with John, but I am a customer of his. He gives great service and top quality. He also sells alluminum pen blanks which are interesting anf fun to turn as well.