Meditation on pain?

I'm not sure what you mean by "meditation on pain", but in this comment Andrei wrote,

Plus, my current mentor has us do pain tolerance exercises every week. Once you switch, pain feels more like heat, not like pain pain. (It's not a damaging pain, just static muscle exercise)

So apparently there is such a thing as self-inflicted (but non-damaging) pain.

This answer is probably a further reference to it.

There is one Tibetan meditation designed to reduce the act of clinging to the body. It is not meditation on pain per se, but might be something you would find of interest.

This practice can be done in different ways, and it is recommended you have prior meditation experience before engaging in it.

Sometimes it is done in cemeteries, sometimes with the aid of pictures, and sometimes with the imagination.

The process of the meditation is simple, take posture, visualize your body, then visualize the process of decay, the skin drying and cracking, falling off, the bugs eating your flesh, take it till there is nothing but bone left. Acknowledge the impermanence of your body, of your life, and try to let go of clinging that you may have towards your body, and the bodies of others.

This meditation is not uncontroversial, and not for everyone. Here is one resource the Satipatthana Sutta with commentary and pictures to aid in the visualization.

The practice described above is related to a more frequently referenced and practiced Death meditation

There is an organisation call Breathworks (associated with my Sangha - Triratna) whose aim is to help people with chronic pain through meditation. Just to quote Jon Kabat-Zinn from the website

The Breathworks approach to Mindfulness-Based Pain Management (MBPM) is the most comprehensive, in-depth, scientifically up-to-date and user-friendly approach to learning the how of living with chronic pain and reclaiming one’s life that I know of.

I appreciate that it's not exactly what you asked for but part of the courses is to use mindfulness directed at the pain itself to enable people to better live with their conditions and enhance their quality of life. I've know many people who have done these courses and they benefitted enormously and in several cases people moved on from this course to more "traditional" Buddhist practice and became very committed practitioners.

Just a note - I'm not pushing this in any way. I just think it is a good example of an established way that people do meditate on pain and I thought you may find it interesting to check out the website.

No need to search pain out. Do sitting meditation, develop a practice, and pain and frustration will find you :)

There's no need to go out of your way to fabricate any state. Pain and pleasure have the same intrinsic qualities. When you sit, you will see this. There is no need to condition oneself specifically for any state, since all states are impermanent, suffering, and nonself.

Many times in the Suttas we find how the body should be seen:

And although this body, Māgandiya, is a disease, a tumour, a dart, a calamity, and an affliction, referring to this body you say: ‘This is that health, Master Gotama, this is that Nibbāna.’ You do not have that noble vision, Māgandiya, by means of which you might know health and see Nibbāna.

Māgandiya Sutta,MN http://www.accesstoinsight.org/tipitaka/mn/mn.075x.than.html

Compassion should not be directed to the body but to all living beings. Clinging to the body must be destroyed.

Pain should be seen be seen as impermanent and what is impermanent should be seen with wisdom as: "This is not mine, this is not me, this is not myself"

"If a painful feeling arises in him, he knows: 'Now a painful feeling has arisen in me. It is conditioned, not unconditioned. Conditioned by what? Even by this body it is conditioned. And this body, indeed, is impermanent, compounded, dependently arisen. But if this painful feeling that has arisen is conditioned by the body which is impermanent, compounded and dependently arisen, how could such a painful feeling be permanent?'

"In regard to both the body and the painful feeling he dwells contemplating impermanence, dwells contemplating evanescence, dwells contemplating detachment, dwells contemplating cessation, dwells contemplating relinquishment. And in him who thus dwells, the underlying tendency to resistance in regard to the body and painful feeling vanishes.

Gelañña Sutta,SN http://www.accesstoinsight.org/tipitaka/sn/sn36/sn36.007.nypo.html

"When an untaught worldling is touched by a painful (bodily) feeling, he worries and grieves, he laments, beats his breast, weeps and is distraught. He thus experiences two kinds of feelings, a bodily and a mental feeling. It is as if a man were pierced by a dart and, following the first piercing, he is hit by a second dart. So that person will experience feelings caused by two darts. It is similar with an untaught worldling: when touched by a painful (bodily) feeling, he worries and grieves, he laments, beats his breast, weeps and is distraught. So he experiences two kinds of feeling: a bodily and a mental feeling.

"Having been touched by that painful feeling, he resists (and resents) it. Then in him who so resists (and resents) that painful feeling, an underlying tendency of resistance against that painful feeling comes to underlie (his mind). Under the impact of that painful feeling he then proceeds to enjoy sensual happiness. And why does he do so? An untaught worldling, O monks, does not know of any other escape from painful feelings except the enjoyment of sensual happiness. Then in him who enjoys sensual happiness, an underlying tendency to lust for pleasant feelings comes to underlie (his mind). He does not know, according to facts, the arising and ending of these feelings, nor the gratification, the danger and the escape, connected with these feelings. In him who lacks that knowledge, an underlying tendency to ignorance as to neutral feelings comes to underlie (his mind). When he experiences a pleasant feeling, a painful feeling or a neutral feeling, he feels it as one fettered by it. Such a one, O monks, is called an untaught worldling who is fettered by birth, by old age, by death, by sorrow, lamentation, pain, grief and despair. He is fettered by suffering, this I declare.

"But in the case of a well-taught noble disciple, O monks, when he is touched by a painful feeling, he will not worry nor grieve and lament, he will not beat his breast and weep, nor will he be distraught. It is one kind of feeling he experiences, a bodily one, but not a mental feeling. It is as if a man were pierced by a dart, but was not hit by a second dart following the first one. So this person experiences feelings caused by a single dart only. It is similar with a well-taught noble disciple: when touched by a painful feeling, he will no worry nor grieve and lament, he will not beat his breast and weep, nor will he be distraught. He experiences one single feeling, a bodily one.

Sallatha Sutta, SN http://www.accesstoinsight.org/tipitaka/sn/sn36/sn36.006.nypo.html

The Buddha did not teach masochism. He tried that path for six years and it ultimately left him no closer to enlightenment than when he was a prince. Pain and frustration will arise in your practice. It's inevitable. Become mindful of these things when they come about on their own. They will teach you quite a bit about yourself. To actively seek pain and frustration out, however, is setting yourself up for failure. No one can continue on a path like that for very long. To do so is also completely devoid of compassion for yourself.

The Buddha taught a dharma that is good in the beginning, good in the middle, and good in the end (Kalama Sutta). There is nothing good about self-inflicted suffering.

To let go of the sensations of pain in the body or of memories of pain, we must practice loving kindness, towards our body and towards our mental contents.

Whenever pain affects us, we must be like a loving mother consoling her crying baby by cradling it. We pick up the pain, and love it. We care for it, we acknowledge it, we understand it, and we put it to bed. We say, "Dear painful knee, I am aware of you, I acknowledge your presence in my life, you are a valuable part of me, I love you.". Repeating like this we remain with the anxiety of being in pain, and the pain itself for as long as it takes for us to be calm and relaxed. We must feel deeply loved. Soon the pain becomes an old friend, and we are able to say, "dear pain, welcome, come, sit with me and have a cup of tea. Thank you for your presence in my life, we are good friends now."

We must not be in a hurry to let go of the pain, it is not our enemy, it is a part of us. Just like a loving mother ignores everything else in her life the moment the baby cries, we must be with the pain totally. We offer our complete presence to the pain, we love it unconditionally. A baby that has been ignored will cry harder for the mother's loving attention, and our pain is similar. We need not fear it, it is a part of us, and we must love all parts of ourselves. To offer our complete presence to ourself is the greatest gift we can give.

By bringing up the healing energies of mindfulness and love, we offer a very comfortable condition for our body to recover. The mind becomes a true friend of the body, allowing it to heal quickly.

If there are particularly damaging memories of pain, our mind will bring it up whenever physical conditions of pain are present. There is no need to fear this either. This is the normal and expected function of the mind. The mind is actually trying to help, we must understand this and not blame the mind, it is our dear friend. Practicing similarly, by loving the painful memories, we cradle them to rest.

Pain itself is not life threatening, even if it isn't pleasant. Everything is impermanent. Pondering on the fruitfulness and preciousness of human life, we remain thankful for experiencing it in all its shades. Developing a heart of gratitude, we welcome the difficulties as old friends.

May you heal well soon, and be pain free.

(Much of this is based on the teachings of Ven. Thich Nhat Hanh.)