Hot Plate Lockup
We got into foil last year. During our learning curve we found that our hot plate needed to be locked up with metal furniture rather than wood. Is this true? When we locked up with wood it shrank and almost dropped out the plate. We have rounded up some aluminum plate from a metal sellers scarp bin for shims but that limits our fine tuning of the plate as I only have a few sizes. I just saw an online post showing a hot plate chase locked up with wood. Now I am wondering if I over thought this again. Also can I fine tune using lead shims or is the lead going have issues when it gets hot also. Lastly if we use wood furniture but always use the same batch of wood furniture if it shrinks when hot will it hit a point where it does not shrink any further and thus be good for always using the same group of wood for lockup or will the wood change after it cools back down.
If the wood furniture is falling out of the chase your lockup is not correct.
Also, old wood furniture might not be true from one end to the other.
Are you leaving the chase lockup in the press overnight?
I found that lockup would become lose overnight.
Best to remove the chase with the lockup once you’re finished and check to see that it tight before placing back into the press.
we generally lock up with wood, never had a problem.
give it a shot. Just make sure your lock up is sturdy, or it can come apart.
You should be able to use the wood for lockup.I think your basic concept is correct, that the wood will shrink to a point, after which it will be stable. As the seasons change, you will find that humidity will cause the wood to swell again, and it might be a good idea to loosen and tighten the quoins before each day’s use.
Metal furniture certainly would not have the problem to the same extent, but would not have the insulating properties of the wood, and you would have to adjust the temp of the heating plate to allow for the transfer of the heat through the lockup sides.
If you continue to have difficulties, there are various other materials you could use right next to the plate which would isolate the wood from the high heat exposure, man-made phenolics and temp resistant plastics, etc.
John Henry
Cedar Creek Press
Thank you all for the feedback. The first time we tried foil we had a good tight lockup with wood. Over time we felt the wood shrank when it got hot which explained our problem with the hot plate coming loose. In retrospect the chase may have gotten warm and changed its shape also.
The problem with the metal lockup is lack of sizes allowing us movement of the hot plate. If need a small change I need to move the die instead. To make maters worse we had a laser temp reader. It turns our that it cant read correctly off of aluminum so we got some false reads. We now have that all worked out
We are also wondering if we need some sort of backer behind the hot plate. We now have it against the press but wonder if we lose heat or might cause some other issue.
We pack with .015 epoxy glass board taped to the platen and nothing else. The other day I saw a video of someone foiling against tympan. What is the way to setup for foiling.