I had two pairs of mesuring syringes (flexcoat) that I used and both of them were extremely difficult to fill without the robber part falling off. Is there anything that can lubricate the syringe so that it will work more smoothly that will not affect the finish, or may be a gob of rodbond to attach the rubber end more securely? Or another brand of syringe that does not fall apart? Thanks.

You must have gotten a bad set of syringes. I have used thousands of those exact syringes and never had one fail or the plunger come off. Very odd.

I assume these were brand new and that you had not cleaned them in any way - never clean the syringes, just pull the plungers back up about 1/2 way, wipe of the outside, and leave them alone. They will not set up as long as you keep them specifically for either the hardner or resin.

The Trondak syringes do not have rubber plungers. The step and plunger is made as one piece so there is nothing to fall or pull off. They are not as smooth as the Flex Coat variety, but work as intended and will solve your problem.

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The first pair was problematic from the start, so with the second pair I cleaned them with solvent thinking it would help. I guess I will just order some more and not clean them at all. Thank you

Don't clean them - with solvent you dry out the rubber plunger and it won't move through the tube cleanly.

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