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Wiring a ST3PF Delay Off Relay
The Fjui ST3PF is a time delay relay switch that comes in numerous voltages and time delay ranges. When you apply power, a coil is energized which flips an internal switch. When you remove power the switch stays flipped for the set amount of time. Unlike most relays, the ST3PF is available in 110 volt AC - there's no need for a separate low voltage power source to trigger the relay. The limitation is that the load being run by the relay cannot draw more than three amps.
I use the ST3PF (bigger than I expected) for a mini sump pump that draws less than an amp. The pump is triggered by a simple float switch. Without the ST3PF to keep the pump running after the float switch turns off, the pump would be turning on and off constantly.
The drawing is presented as an alternative to the "8-pin timer wiring" one that I didn't find very helpful. The drawing shows a basic switch circuit (left) with the addition of an ST3PF (right). Only four of the eight pin connections are needed/used.
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Frame press gasket
Ryan emailed me regarding my comment that the gasket tape doesn't stick well to polyurethane and wondered if sticking it to the platen might be better.
A platen mounted gasket might stick better, but it seems like it would be easy to damage the gasket even if you weren't in the habit of sliding things in and out of the press. Mounting the gasket to a rabbet that runs around the the perimeter of the platen might work.
Despite the poor adhesion, the gasket on my first press has stayed stuck and functional. Joe recommends acetone or xylene to prep polyurethane for seaming so I gave acetone a try on my last press. I used a strip of laminate to protect the wood and a folded bit of acetone dampened (not wet) Scotch-Brite to clean a strip wide enough for the gasket. While adhesion is better, its still not as good as mounting the gasket to lacquered wood.
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Box VS Flat membrane
Peter brought this up earlier [link] and I thought I'd expand on my reply.
Flat membranes are easy to seal, but you cannot veneer things more than a few inches thick. To get maximum capacity the membrane should be as loose as possible. Let the sides of the membrane curve in from the corners as much as you can. Even though you cannot gain much on the diagonal corner-to-corner dimension, the extra material everywhere else really helps. The membrane-seal-platen design also adds capacity. With the membrane on top of the frame, lost capacity equals frame thickness because the membrane will have to travel that extra distance (if there is enough material to do so) when vacuum pulls it tight to the frame. I tried a reversible frame on my 4x8 press thinking it would increase capacity, but raising the membrane up like that had a serious negative effect on capacity.
Box membranes are a good choice for veneering thicker items but they are hard to make and seal. I don't think either of my attempts would would work well with an auto cycling setup. I'm also not sure if my glued box joint is any better than my folded one. I wonder how the commercial ones are made.
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Toe Kicks and nailers
I decided that my current job had to be done without height and width consistency. The earlier mentioned rail broke the height and having all vertical rails - including side trim - be 1-1/2" broke the width. The broken width complicates how I do nailers and toe kicks. This slowed me down because I had to both come up with a way to do them and because my boring machine setup wasn't very accommodating.
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Dowel connectors
I'm working on a job where the cabinets run floor to ceiling. They have a dividing rail detail that separates two boxes by 22mm. I incorporated it by extending the box sides 11mm past the box top/bottom so that the boxes stack on the extended sides . I needed something to align the boxes. Dowel connectors don't take much space and seemed a good solution.
I had played with dowel connectors before (image) and the sample aligned quite well. I've also had good results using the pictured connector to join the 16mm bottom of metal slides/sides to the drawer face.
This time I was working with a similar connector (darn that camera) that Haffele calls permanent. The advantage is that both ends go into 10mm x 12mm deep holes, so only one setup is needed. The female end is also a simple hole, there's nothing to get hung up on when sliding the the boxes into alignment (theory at this point). The disadvantage is that they do not align well. This is noticeable when you snap the two pieces together, they aren't concentric. Hammering them in crooked makes it even worse. I ended up having to clamp the box sides into alignment, with the connectors between and barely in the holes, and then hammer the two pieces together.
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Prefinished Plywood
The bowing is unacceptable, but what can you do, how many times can you send stuff back? The extra cost of EuroPly might be worth it. When they get around to NAUF (no added urea formaldehyde), it'll be a great "green" product - the materials are FSC (Forest Stewardship Council) certified.
The finish is surprisingly durable, though the stuff I got seems to have two coats that aren't bonded well. At cut edges, a bit of the top coat can flake off. The drawback for me is that I much prefer a continuous finish coat. Using prefinished banding leaves a veneer thickness of unfinished wood that I hate. I came up with a special applicator for applying finish to that edge. This turned out not to be as tricky as expected because the finish - at least my water-based one - doesn't stick to the prefinished surfaces. Its still lousy because you cannot have a nice eased edge. My solution was double banding, an unfinished maple edge followed by the prefinished edging. This allowed me to have a 1/16" radius on the edges. The finish they use is pretty amber and it wasn't until I had coated the exposed Maple before I thought of tinting my finish to match.
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