1. Using the correct speed and feed settings for the density of Precision Board you will be machining is crucial. This will allow you to achieve optimum chip load. Having the proper chip load allows the cutting tool to move in and out of the material quicker, which will prolong the tool life and leave a smooth edge. Be sure to check out the excellent database LMT Onsrud has for choosing the right bit for the right material.
2. If you will be using Precision Board in an oven or autoclave, ensure that temperature ramp up does not exceed 1˚F per minute. This will allow the temperature to be evenly absorbed during heat expansion, which will reduce the possibility of internal stress and warping.
3. When ramping down the temperature after autoclave or oven curing, temperature ramp down should not exceed 2˚F per minute. This will allow the tool temperature to drop slowly so contraction does not cause internal stress and cracking in the thinner sections of the tool. In thick tools with thin webs or sections, cool down should be even slower. Prior testing is always recommended before heat cycling on actual tool.
4. Instead of laminating together sheets to form a large block, consider using a custom block instead. By providing a drawing to Coastal Enterprises we will make a custom-sized block in the rough shape and size of your tool. This will allow you to purchase less material, eliminate assembly and reduce machining time.
5. Do not worry about Precision Board outgassing. Outgassing occurs when a urethane tooling board, other than Precision Board, is used to make a composite layup tool which is then heated during curing of the composites laminate. When a typical urethane tooling board is heated, it outgases, which releases byproducts that keep the composite laminate adhesive from curing. This obviously ruins the composite laminate and can damage the urethane tool. Precision Board plus does not outgas.
6. For higher temperature applications, Coastal Enterprises offers Precision Board High Temp HDU, or PBHT. PBHT is a “closed cell” rigid urethane foam board made specifically for applications of up to 300˚F continuous exposure. PBHT high density urethane foam board is available in a wide range of standard sheet sizes and standard densities and can be cut or bonded into a variety of shapes for final machining or shaping.