Abstract: A joint (24) and method of making the same for interconnecting various segments of coolant tubes of heat exchangers. The instant joint (24) includes a first tube (26) having a necked end (38) with a reduced outer diameter (40) and a second tube (30) having a frustro-conical portion (34) with a steadily increasing inner diameter. The necked end (38) of the first tube (26) is inserted within the frustro-conical portion (34) of the second tube (30) thus forming a frustro-conical portion shaped increasing gap space therebetween. The increasing gap space is filled with epoxy adhesive to form a bond (44) of steadily increasing thickness between the outer diameter (28) of the first tube (26) and the steadily increasing inner diameter of the frustro-conical portion (34) of the second tube (30).