Pen mandril saver

[Penpal]

The question of which brand, type of specs in particular with regard to bearings to use in a Mandrel Saver is a really interesting exercise I scoured the specs of all the bearing manufacturers its a fallacy to assume there is little or no regard to end thrust in a straight bearing which I ended up using in mine for two reasons an angular bearing or thrust race is rarely made in this size and if it is costs the earth, replacement is easy.

My lathes ie two of them use angular bearings or thrust bearings ie the VL100 and VL150 others dont and the life expectance of either type is long in service. Replce bearings for the USA Mandrel Saver from my local Bearing supply guy fitted in the (Precision Saver) was peanuts.

Peter.

 

[21William]

Food for thought, thank you Peter.

 

[ZuluTiming]

I used the cheapest bearing around, the 6201, and it is working just fine

 

[21William]

You guys are tempting me to have a go at making my own! As if I haven't got enough jobs at the moment

 

[Penpal]

Agree with the old 6201 any popular bearing is cheap as an added bonus IMHO.

Peter.

 

[qquake2k]

I do note with interest you use a real lot of spacers every one is a potential slip factor the other is mandrel savers are better used with a cut off mandrel ie the thread cut off because there is a distinct change in size right there that can promote both a wobble and a misfit. An advantage of a longer nose mandrel saver is you can straight way do away with two spacers on the outboard end. Using the Collett chuck or the slip through feature in both ends of your set up and only turning one half of a pen at a time you could restore the grip for turning. The mandrel saver I use and the one that went to the north of Australia to Tennant Creek made for me here are turned from a tough steel giving long life and precision made.

Peter.

You know, you make some good points. I normally turn only one body at a time, but I do always add an extra bushing at each end for a little extra clearance at the head and tail stock. In the case of the wood blanks, those were for an Apex pen, which requires the short piece for the plunger. I decided to put them all on the mandrel at once, since the one piece was so short. But even with single blanks, I still had problems with the mandrel saver.

I decided to try it again today, and it seemed to work better. Probably a combination of a lighter touch when roughing, and only a single bushing at the tailstock end. I also like your point about the extra clearance from the longer nose of the other style mandrel saver. They sell that type here at Wodturnerscatalog.com. The price has come down, so I've decided to order one. Regardless, I'm sure it's higher quality than the PSI version I have now.

 

[Dalboy]

You know, you make some good points. I normally turn only one body at a time, but I do always add an extra bushing at each end for a little extra clearance at the head and tail stock. In the case of the wood blanks, those were for an Apex pen, which requires the short piece for the plunger. I decided to put them all on the mandrel at once, since the one piece was so short. But even with single blanks, I still had problems with the mandrel saver.

I decided to try it again today, and it seemed to work better. Probably a combination of a lighter touch when roughing, and only a single bushing at the tailstock end. I also like your point about the extra clearance from the longer nose of the other style mandrel saver. They sell that type here at Wodturnerscatalog.com. The price has come down, so I've decided to order one. Regardless, I'm sure it's higher quality than the PSI version I have now.

Jim what speed are you turning at and is it a problem when roughing from square to round. I find that fast speed and sharp tools(which I am sure you have heard before) helps and a light touch.

 

[qquake2k]

Jim what speed are you turning at and is it a problem when roughing from square to round. I find that fast speed and sharp tools(which I am sure you have heard before) helps and a light touch.

I generally turn at about 2200 rpm. And yes, I try to keep my tools sharp, and try to use a light touch. I don't always succeed on both points...

 

[wm460]

I have a TB mandrel saver which looks the same as the PSI one but is meant to be made by Vicmarc, not real happy with it. the best one is the one I got from Peter.

I though you might be interested in this.

https://www.youtube.com/watch?v=KTbK-fn0T1E

 

[qquake2k]

I received the precision machine center from Woodturnerscatalog.com today. It does seem to be better made. I like the design of the long nose, gives a little more clearance on the right side. I'll know more as I use it in the next few days.

 

[ChrisF]

Interesting thread. I've also had problems with bushings/mandrels not being consistent in size. A set of 4 bushings I had recently had three with identical i/ds and one just slightly smaller.....enough to make it not fit ont he mandrel without some tweaking. I bought the Axi saver, but the mandrel didn't fit so it went back.

So....I've just got the Chronos saver, arrived today. I also got a 1/4" reamer and a length of 1/4" silver steel bar. I've reamed the bushings and needed to ream the saver a touch, but now everything fits like a glove. Perhaps now my pens will be round! Or at least if not I can stop blaming the equipment.....

 

[21William]

Having a reamer to suit your mandrel is a good idea.

I'm setting up from scratch and as I'm not interested in slimline pens (at the moment) I've decided to use a 7mm system using a collet chuck and a piece of silver steel. I've yet to decide whether to buy the Chronos saver (and ream it out) make my own or make a "saver collar" that fits between the mandrel and a standard live centre. Can't do much at the moment till bits start arriving from China amongst other places!