**7. Conclusion**

**6.1. Other important issues: twisting of yarns, beat-up mechanism, and machine** 

**Lace machine yarn carrier**

Excessive yarn bending to payout

Poor tensioning for large HS yarns

bobbin capacity

Non-rotating terminal eyelet **Maypole yarn carrier**

No clutch-direct

drive

Adequate tensioning of large HS yarns

Larger carrier/ bobbin capacity

Rotating terminal

eyelets

**Lace fabric formation**

point

parts

twist

Beat-up mechanism

Yarn fiber disintegration due to abrasion with the machine

Buildup of yarn

Fixed angle to fell

**Maypole fabric formation**

Variable angle to fell point

Minimal abrasion with the machine parts

Minimal imparted yarn twist

No beat-up mechanism

The carriers used in lace braiding are free to rotate about the plate. Motion about this additional degree of freedom will be exacerbated at high speeds as inertial effects increase and may potentially cause problems. The freedom of the carrier to rotate during braiding can cause excessive buildup of twist in the yarn. **Figure 11** illustrates an example of this phenomenon

**design**

**Modern lace machine**

70 Engineered Fabrics

Frequent clutch failure

Accumulation of debris in driver plates

Complex mechanism **Conventional Maypole braiding machine**

No clutch-direct

drive

Simplified mechanism

No axial yarns Axial yarns Small carrier/

Accumulation of debris in driver plates

**Table 2.** Problems encountered with lace braiding machine evaluated.

**Figure 11.** Buildup of excessive twist in yarn.

Lace braiding technology has been introduced and a brief historical context provided. A description of how the components function has been presented. The lace braiding machine components and their functionality were described to demonstrate how the machine works as well as to assess the limitations for producing structural scale composite preforms. Based on the experiments that were made on the modern lace braiding machine, the machine deficiencies for manufacturing composites (listed in **Table 2**) are discussed. Suggestions for remedies in the machine design and operation are presented to enable future progress to be built upon addressing the current limitations while further advancing the future of lace technology in new areas such as space and aerospace. Complete re-design and construction of a machine suitable for composite preforms were considered beyond the scope of the research and left for future work.
