Dulcinina -- string tuning "trick" to avoid breaking strings when tuning them:  Never tune a string that isn't humming.  Decide which tuner controls the string you want to tune.  Pluck the string, and while it's vibrating give the tuner a quick quarter turn.  If you do not hear the string change tone, STOP -- you are not turning the right tuner.  Find the right tuning knob and try again.   If the string does change tone, pluck it again and tune it to the note you want.

Nina, you can trim the strings without cutting them by bending them back and forth and back and forth and back and forth until they break on their own, which will almost always be right at the point where they emerge from the hole in the post.  That way nothing will be sticking out.  I usually don't bother with that and just snip them with wire cutters, but then I use the side of the wire cutters to bend the sharp end in so that they don't stick out straight.

Another option, though it looks kind of funky, is not to trim the ends at all, but when you are dong to run them along the side of a pair of scissors. The string will curl up into a bouncy coil.  That is the same technique you've probably used with ribbon when wrapping presents.

In the future, I hope we all have those self-trimming tuners that Brian G mentions above.

Hi Everyone, I changed my bass string using the bass string from my old dulcimer.  We have one music store and the guy was as helpful as he could be but had never even seen a dulcimer before. And I live in south central KY! He  pulled out some strings and we eyeballed it. They don't carry individual strings anymore, and I had to buy a pack.  I put on the string and promptly broke it.  So I took off the bass string from my other dulcimer and I have no idea the gauge.  But it plays much better. Now I have a couple sets of melody and middle strings.   They'll eventually get used. 

I also trim the string before winding.  I couldn't get as close to the end as I wanted for the final trim and there's a sharp end sticking out.  Wished I had read the hint about leaving enough string to make a little kink at the end.  This dulcimer has different tuning pegs than I'm used to.  The middle and melody strings have nothing sharp sticking out and I can't imagine how they trimmed the strings so close. I was glad to read all the responses. 

Nina

 Brian, Interesting, and good recommendation. If I can ever find plans for a guitar head dulcimer, I'll give these a try. 

Jan, too funny. 

I also trim the string before I put it on, leaving about 2 inches past the tuner.  A few of my dulcimers have self-trimming tuners (they have built in cutters and trim the string as you are replacing it), and they are absolutely excellent. I think they are D'Addario Planet Waves, but I am not 100% sure.  But I went from being skeptical of them to a firm believer pretty much immediately:

D'Addario Planet Wave Tuners

That's my problem--it's my strings that are apparently learning challenged! 

Seriously, though, these are all good suggestions.  I may even use some of my old strings and practice with some shorter scale instruments til I get better at this.

This is my method too, but I leave 3.5-4 inches for winding, because somehow, I always end up short. I like to go around the post 3-4 times.  Looks neat, but holds well. My hand from pointer to pinky is 4 inches, so I just lay my hand over the post and cut the string there, then wind. I like to keep my face back from the instrument when I am tuning. If I do break a string, I won't end of with the nickname "Scarface". The more you change strings, the more comfortable you are doing it. And practice makes perfect. Isn't that what they say?

I actually first trim the string length so there's only about 2 inches of slack, then thread in the peg and wrap it around a couple times.  Then I lay the string in the nut slot and put my middle finger of my left hand on top of that slot to hold the string in place (a capo would work too, as Dusty said).  At this point there's still enough slack to hook the other end of the string on the tail end pin... and I use the thumb of my nut slot hand to pull up the slack as i start tightening so the string doesn't pop off the tail pin.  I then use my right hand to turn the peg a couple more times to tighten it up.  When it's snugging up enough I remove my left left hand from the nut area and make sure the string is in both nut and bridge slots as I finish tightening.  Sounds more complicated than it is- once you've done it a few times it's no big deal.

I once changed a whole banjo skin without taking the strings off the peghead end by using a capo to keep them in place on the neck while changing out the head skin.   lol...talk about wanting to save a couple bucks...

Yes, Jennifer, a string winder makes changing strings a lot faster and easier.  I have a string winder that is also a wire cutter, like this one by Planet Waves .

Another tool to use is a capo.  I can't believe I never thought of this and had to get the idea from Butch Ross a few months ago, but it will make your life easier if you use a capo to hold the string in place while you thread it through the tuner post and begin your winding.  Once the string is taught enough you can remove the capo, but before then it will make your life much easier.

Ken makes a great point.  It's not desirable to go around the post or peg eight or ten times.  
I approach it a little differently than Ken, but we both get the same results.  I trim the string before I even put it on-  holding it over the instrument and trimming it to leave only about 2.5 inches for winding.  Typically this means I'm trimming off about 6" from the original string length.  The length from tailpiece to cut end will vary by an inch or two depending on which peg you are going to.
Once the string is on and tuned, I trim the little end at the peg to a short length and then I take a pocket-sized needle nose pliers and kink the cut end back on itself so it can't prick my fingers...or you can leave a half inch and with the pliers just tuck the cut end back into the hole out of the way.  I hate getting stabbed while restringing!  

Trim off the excess string, ladies.   That way you don't have a bird's nest around the pegs.   I usually go through the hole around the post and back through the hole, the pull the string up to get rid of the slack.  Then I use the tuners to get the initial tune.  After that I snip off the excess string, leaving only a half inch or so.  With the bass string I'll go through the hole, around the peg twice then back through the loop as I pull up the slack.  That locks the string in place.  Then tune and trim.

Maybe you could show me a few tricks, Jennifer!  Mine always end up looking like a 2 yr old wearing oven mitts attempted the task. 

Sometimes I'm even surprised they manage to hold a tuning!

It's probably fear that keeps them in their place! 

Um....perhaps Jennifer does not, yet, (like many of us!) feel proficient about changing strings?  This is an acquired skill that takes quite a bit of practice for some of us....

Why bother worrying about the string gauge?  If the string is too thick for your preferences, the actual gauge doesn't matter.  Just go to your local music store with your instrument and have the clerk pull out strings and compare them.  You won't know what gauge you prefer until you have tried a few.  My local Guitar Center sells individuals strings for $1.  Just buy a couple different thinner strings and try them all until you find one you like!

Jennifer -  the problem is that most of the employees at a generic guitar store either don't have a caliper, or don't have a clue how to read a caliper.    Not one of the four shops here in my town has a caliper...

Jennifer - yes, you can definitely just measure the string with a caliper to determine its gauge.  As has been mentioned, there's nothing special about dulcimer strings; a regular old caliper or micrometer will work on a dulcimer string just as well as it will any other string. I had to do this recently for a harp dulcimer I acquired as I had no idea what gauges the harp strings were.  :) 

Thanks, guys. I got on Strothers string gauge site and it recommended a 19.  So I'm going to try and 20 and 22 and see how I like them.

Dusty is right, Nina.  The two things you need to know to determine string gauge is the VSL and the open note you want to tune the string to.

Nina, I think Bob is right. I usually use a .24 bronze wound string for my bass strings on my instruments in the 26.5-28" VSL range. But it is a matter of preference.  If you prefer lighter strings, go dow to a .22 or .20.

There is no difference between guitar strings and dulcimer strings other than the name on the package. But the good news is that single strings are pretty cheap. Why not buy 2 or 3 in the .20-.24 range and see which ones you prefer?

For future reference, you might consult the Strothers String Gauge Calcuator where you indicate the VSL and the note you want to tune to and the calculator will tell you what gauge to use. I've been told it errs on the light side, so feel free to go a little bit heavier than indicated.

I generally use a bronze or nickel wound .22 or .24 gauge on the low string.  It's really a personal preference, up to a point.  Especially if you want to go to lighter strings.  Heavier strings cannot be tuned to as high a pitch.  Light strings will be soft and unresponsive if they are tuned too low.  If you tune somewhere between C and E on the low string you could even use a .20 or .18 unwound string for the base if you want to.

Is there a way to determine the string gauge on strings on my dulcimer.  I bought a Folkart at KMI and the bass string seems kind of heavy.  The dulcimer is a 27.5 VSL  and the body depth deeper than traditional dulcimers.  I know that a heavier gauge gives a louder sound but I'm having a little trouble pressing the bass string and some buzzing.  It's a wound metal gold string.  We have a local music store and the people know a lot about guitars but nothing about dulcimers.  Any suggestions? Nina