Mandrel lesson PLZ

[Vectorr Ris]

I purchased the Jet Pen Lathe (Starter Kit) #900-0100 from The Woodturners Catalog "Fall issue '04/'05" which came with the "0" MT pen mandrel and I have made some nice pens so far.

I decided to try something new, and when I was working on 10K Americana Cigar Pen #050-4010 when I discovered the bushings (#155-4101) do not fit on my pen mandrel. The magazine says they are specifically for the "Double Pen Mandrel" which I thought I had, but I cannot find that mandrel listed in the magazine. One bushing does slide on to the mandrel easily, but the other three have to be hammered on and I'd rather not do that!

Question: Can someone explain the differences between the 0MT, 1MT, and 2MT mandrels? I thought the morse taper was the pointy thing that fits into the head stock (yes, I'm newbie, hehe.) Are all the shafts on these mandrels the same size? Or do they change with each MT size?

Thanks in advance for your help!

[Terre Hooks]

You are correct in your thinking, the Morse Taper size is for the fitting to the headstock.

The shafts are all pretty much slightly smaller than 7mm.

I'd suggest giving Woodturner's Catalog a call. (Isn't that Craft Supplies USA?) They are very helpful on the phone.

[Vectorr Ris]

Ah, ok. So I'd have to buy another and screw it in?

[Harry Goodwin]

I have worked with PSI but have the same lathe. If it is the mini lathe it has a M2 morse taper. If the bushings are new make sure you have not built up some glue ect and if necessary sand it off and try. I agree don't drive them on. I thought all the bushings fit with a 7 MM hole. If you used the bushings they may need reaming by hand wwith a 7MM drill as well if glue involved. Not an electric drill or press. Hope this helps. Harry

[Chris Lee]

Victor,

I would agree with Terre and advise you to call Craft Supplies. You will have a hard time finding a 0MT mandrel. I think that is why Jet includes it with the pen lathe. PSI might also have it.

As far as the diameters of the shaft on the mandrel, each manufacturer has a different size. We are talking miniscule but it means some bushings won't fit. I know Craft supplies bushings do not fit on Berea Mandrels. Unsure about PSI though as I don't have one.

Chris

[Kurt Aebi]

The mandrels all measure around 0.240" +/- a few thousandths (0.001"), so the I.D. (Internal Dimension) of the bushings will probably vary accordingly as well from manufacturer to manufacturer. This would be referred to as a 7mm Mandrel or in Berea's case an "A" mandrel. Therefore, it would not be a gaurantee that all "7mm" bushings or 7mm kits can be used on ALL of the mandrels, (but you may also not experience a problem - since manufacturing tolerances are usually +/- 0.005" - "plus or minus 5 thousandths")

Generally speaking, penturner's stick with one brand of mandrel (PSI, CSUSA or Berea) and the kits from that supplier as well. Now it gets confusing as these 3 types are available from numerous sources and not just the Mfg's own supply house.

What I do is measure each mandrel and bushing and keep like sized parts together and measure the brass tubes from the pen kits to determine which mandrel is appropriate. I use a set od digital calipers for these measurements. (Harbor Freight has a decent usually for around $15.00 and for occaisional use will hold up just fine - I have a roughly $100 set of Mititoyo's that are industrial quality)

I have never had any issue with any brand of slimline pen kit not working on my PSI mandrels -not to say I won't, just haven't to this point. I've done around 100 pens and have gotten my kits from the FPP (unknown brand - to me), e-bay (again, unknown), PSI, Berea & CSUSA. In fact I didn't even know until a few weeks ago that there were differences in the mandrels! :o

I hope that I have helped, rather than caused you more confusion. Anyway, I say get some kits and get to turning and don't sweat it until you have an issue - in which case, get onto this forum right away and post your dilema. These guys/gals here will get you out of just about any jam that you can get yourself into! The've been a real BIG help to me! :D

[Robert E Lee]

Vec, take some fine sand paper or emery cloth on a dowel and clean the inside of the bushings out.
Bob

[Vectorr Ris]

UPDATE

Last night, after cleaning the mandrel and trying to fit the (new) bushings again, I realized only one of the bushings would slide on and the other three didn't. The only thing I could think of at that point was maybe some of the bushing were mispackaged.

I called CSUSA as soon as I got home this morning and the very helpful CS lady said she would send out another set of bushings and a 2MT mandrel. She also said the pen turner's starter lathe I bought *should* have come with a 2MT, and not the 0MT. According to the catalog and the lathe docs, a 0MT was included. Hmmm...

Out of curiosity, I will pick up a set of calipers from Harbor Freight like Kurt suggested. I held off due to the amount of cash I've put into the hobby so far until I could sell a few more pens, and since there are two retail stores within driving distance, I'll just tell my wife it was Kurt's idea and run! hehehe!