How to make trailrenderer collider?

I´m new at unity and i'm trying to make a game with line collisions. I just found in unity forum a script that makes a trail collider. The question is that only part of that trail makes collision (the part next to the game object attached to it) and i want that the all trail collider. I think there´s something abount linecast but i can not understand what exacly. I realy neeed help. Here´s my script:

 var pencil:GameObject;
 var time : float = 20.0;
 var rate : int = 10;
  var change:String;
 private var arv3 : Vector3[];
 private var head : int;
 private var tail = 0;
 private var sliceTime : float = 1 / rate;
 var hit : RaycastHit; 
  
 function Start () {
     arv3 = new Vector3[(Mathf.RoundToInt(time * rate) + 1)];
  
     for (var i = 0; i < arv3.Length; i++)
        arv3[i] = transform.position;
     head = arv3.Length-1;
     StartCoroutine(CollectData());
 }
  
 function CollectData() : IEnumerator {
     while (true) {
        if (transform.position != arv3[head]) {
          head = (head + 1) % arv3.Length;
          tail = (tail + 1) % arv3.Length;
          arv3[head] = transform.position;
        }
        yield WaitForSeconds(sliceTime);
     }
 }
  
 function Update() {
     if (Hit()){
        Debug.Log("I hit: "+hit.collider.name);
        change=hit.collider.name;
      }
      if(change=="Sphere")
      {
      Debug.Log("hit change");
      Destroy(Sphere);
      }
      
      
 }
  
 function Hit() : boolean {
     var i = head;
     var j = (head  - 1);
     if (j < 0) j = arv3.Length - 1;
  
     while (j != head) {
  
        if (Physics.Linecast(arv3[i], arv3[j], hit))
          return true;
          
        i = i - 1; 
        if (i < 0) i = arv3.Length - 1;
        j = j - 1;
        if (j < 0) j = arv3.Length - 1;
     }
     return false;
     }