Choosing a Mandrel (information)
Deciding which mandrel is best for you is a tough job, especially if you are fairly new to call making, calls, lathe tools, and such. Our suggestion is to visit some of the various forums pages to get feed back from other call makers on their likes and dislikes for the various designs available. Keep in mind, that people are bound to have several different opinions, and in the end it will be up to you do decide which mandrel you want. The most common mandrel these days is an expanding mandrel.
Here are some details that may help you decide which mandrel is best for you.
- I regularly get asked what is the difference between the EXM series mandrels and the EA series mandrels. Well, first is the obvious... the price. The EXM series mandrels are almost 3x the cost of the EA series. Here are the reasons why: Material - the material used in the EXM mandrel is much tougher than that of the EA series. Design - the EXM series mandrels has a different design, including knurling for grip that the EA series do not, and an improved expansion design over the EA series. And finally, because they come from two different manufacturers... One charges more for theirs than the other, likely because of the reasons above. In the end, we look at the two different mandrels this way... You get what you pay for. If you are looking to start cheap to see if you like it... then probabaly the EA series would be a good bet. But if you're already hooked, and are in it for the long haul... it may pay to buy the mandrel that will have a longer life span due to better material and improved design. Which mandrel is right for you? Well that is up to you.
- The expanding mandrels are available with a #2 Morse Taper in 5/8 and 3/4" and with a #1 Morse Taper in 5/8" as well as various mandrels with a straight shank for use in conjuntion with a collet chuck. If you have a different mount on your lathe, you will either need to find/make an adapter that will work, or look at a different style of mandrel. To help identify your Morse Taper, this link has the specifications for the various tapers to compare to yours. The collet chucks we carry mount to the threaded portion of the spindle and you just need to match the spindle thread to the collet chuck thread, and then match the mandrel shank size to the same size collet.
- Mandrels are chosen by the diameter of the bore they are intended to hold. If you have a step bore, and choose to use a step mandrel, you are only concerned with the largest and smallest bore diameters. A 5/8 bore duck barrel will use a 5/8 mandrel. A step bore with a 7/8" socket for the keg, and a 5/8 bore at the mouthpiece end would use a 7/8 x 5/8" stepped mandrel.
- The Stepped mandrels (EA series) are used for step bored blanks such as goose call barrels or LA style duck call barrels. They only hold on the end, which is the smaller diameter of the two. The larger diameter or the "step" is only a support/locating section. It does NOT expand there.
- Expanding mandrels only expand about .020-.030" safely. So you CAN NOT use a 5/8" mandrel for a 11/16" hole for example. It will not expand that large and remain centered - as well it most likely will be bent after that much beyond its limitations. Expanding mandrels are not a "one size fits all" setup - they are a "one size fits one size up to about .015" oversize" type deal. The expansion range is just not there. In addition, the non expanding section of the mandrel that is closest to the shank, is the size listed, so if the bore is larger than the size listed, the blank can wobble on the mandrel since it is only "held" at the end with the expanding plug or screw.
- The MVS and PLS are not designed to be used without the tailstock in place. If you require an unsupported end on your mandrel, neither the MVS, PLS, nor CLS are mandrels you will want to use. You will want an Expanding mandrel or contact us for a a stub version of the PLS.
- The Expanding mandrels are available in various sizes and configurations. Custom sizes are possible, as long as there is a madrel on the site that is larger than the size you want, and that the expansion screw is not larger than the size you want. The MVS, PLS, and CLS can be made in any custom size you require including stepped mandrels (multiple diameters on one mandrel) for goose calls and duck calls utilizing guts and orings.
- The Expanding mandrels with Morse tapers require the customer to build a "Draw Bar" to secure the mandrel in the headstock. A draw bar is in essence a long bolt that goes from the back of the headstock into the actual mandrel and is used to "draw" the mandrel into the taper very securely and hold it there. The threads in the back of the Expanding mandrel are 3/8" - 16tpi for the #2 MT mandrels and 1/4" - 20 for the #1 MT mandrels.
- Turning on the face of the call (mouthpiece and end face) is possible with all of the mandrels. The expanding mandrel will require you situate the blank hanging off the end of the mandrel and can only work on end at a time. The MVS, PLS, and CLS which have recessed cuts spaced to allow end work and "bell mouthing" on both ends without moving the blank, but they require a very narrow tool to allow access to the inner wall without touching the mandrel.
- MVS and PLS mandrels require a very accurate hole. Drill bits are NOT good at giving accurate holes, they are not designed to be extremely accuate. Chucking reamers and boring bars are meant for bore accuracy. It is strongly recommended that you drill your blanks 1/64 undersize, and then use a chucking reamer to open up the bore to the proper size. One way of looking at it, is if you dont already know why you need an MVS or PLS... odds are, you probably will be better served with an expanding mandrel.
In the end, it really comes down to 'you', the customer. We can suggest things until we are blue in the face, but what is truly important is that you are happy and the only way to achieve that is for you to decide what would work best for you - for the way you plan on turning calls. We strongly suggest that you read the manuals on the Downloads & Manuals page, familiarize yourself with how they operate, and compare that with your current style. Or if you are new to call making and have no current style, get on some of the forums and see what others have to say about the styles of mandrels they use and why they like or dislike them.
If you are like many people that just want a recommendation, maybe this will help... We pretty much use expanding mandrels anymore, and strongly recommend expanding mandrels for beginners. So, the short of it is, our recommendation is a collet chuck, with straight shank expanding mandrels.
For more help - check here!
Happy Turning!
