Showing 0 products
Frequently Asked Questions
When are high-temperature caps needed?
When the process will destroy an ordinary one.
Powder coating cure and stove enamelling are the common cases.
E-coat bake and heat treatment are others.
Vinyl and standard rubber soften and distort at those temperatures.
They can also stick to the coating or break down entirely.
The cap has to survive the whole cure, not just reach it.
What happens when a cap fails at temperature?
More than just losing the masking.
A softened cap can bond to the coating and become very hard to remove.
One that breaks down contaminates the part and the oven.
Material left in a cure oven affects everything processed afterwards.
The failure is rarely confined to the part that failed.
That is why the material is specified rather than substituted.
Why silicone?
It tolerates repeated cycles at coating temperatures without hardening quickly.
It does not adhere to cured powder.
It stays flexible enough to remove cleanly.
Those three properties together are what the process needs.
Performance across many cycles makes the higher unit cost economic.
Cheaper materials cost less per cap and more per part processed.
How should I read the temperature rating?
As the process sees it - temperature and time together.
A peak rating may not cover the whole cure duration.
Repeated cycling is a different demand from single exposure.
Matching the rating to the actual cure profile prevents surprises.
Oven temperature and part temperature can also differ.
Manufacturers publish continuous and intermittent figures separately for that reason.
How do I know when a cap is worn out?
By hardening, discolouration and loss of elasticity.
Silicone degrades gradually rather than failing suddenly.
A cap past its useful life is still being fitted.
That is the trap this material creates.
Tracking cycles catches it systematically.
Inspecting for stiffness on removal catches it practically.
What if the temperature is above silicone's range?
Metal masking or high-temperature tapes are the alternatives.
Purpose-made steel masking survives temperatures silicone cannot.
High-temperature tapes cover flat and irregular areas.
Both carry their own handling and cost consequences.
Metal masking is generally reusable many times over.
It is also slower to fit and harder to make for complex geometry.
Are they interchangeable with ordinary caps?
They will do an ordinary cap's job, but not economically.
High-temperature caps cost more per unit.
Using them where vinyl would do wastes money.
Using vinyl where they are needed loses parts.
The correct choice follows the actual process profile.
Where a workshop runs both cold and hot processes, holding both types is the sensible approach.