Easy-on/easy-off throat plates?

[cgallery]

So has anyone figured out a way to make BT3000 throat plates that don't require screwing-on? I noticed a lot of the cabinet/contractor saws have throat plates that rely on gravity to hold them in place.

But those saws have thicker throat plates that may be a little heavier. I'm trying to figure out some sort of fastener (maybe even using magnets) that would allow me to easily and quickly swap one throat plate for another.

I experimented a little today and discovered that a throat plate made from 3/8" BB plywood seems to stay put okay (as long as the plate isn't zero-clearance at the back of the blade, which may grab it and lift it up).

Neverthess, having some sort of fastener that is cheap, fast to operate, and doesn't contribute too much to the complexity of making new plates may be a pretty good idea.

My old contractor saw had a spring clip that went under the table at the back of the saw, and a screw at the front.

Any other ideas?

[gwyneth]

Something like Velcro.

Either the industrial-strength kind or a plastic version (I've seen it a few times with rallye stopwatches so they can be affixed to the dashboard).

Since gravity is helping the throat plate, the plastic version might not be necessary.

The industrial-strength stuff, with sticky backing, should be relatively easy to find.

[cgallery]

Something like Velcro.

Either the industrial-strength kind or a plastic version (I've seen it a few times with rallye stopwatches so they can be affixed to the dashboard).

Since gravity is helping the throat plate, the plastic version might not be necessary.

The industrial-strength stuff, with sticky backing, should be relatively easy to find.

The only problem I can see with Velcro is getting the throat plate flush with the table top each time. I'll think about this...

[jackellis]

I just bought the Jet cabinet saw and its throat plate has four set screws for leveling but it's held in place by a combination of gravity and a snug fit. Getting the thing out takes a bit of muscle. So one thing to consider is whether you can make a shop-built throat plate that fits snugly in the table's recess.

[LarryG]

If you're been using the plastic ZC plates, you may have dis-remembered that the stock throat plate has a spring clip on the end closest to the front of the saw. Emulating that, perhaps using a modified cabinet door latch, might be one way to go.

Another possibility involves rare earth magnets. Since the BT's main table is aluminum, you'd have to have something for the magnet to stick to ... maybe steel screws threaded into the bosses in the throat plate recess, which would double as height adjusters. Epoxy the magnets to the TP in the appropriate locations and you're done.

[cgallery]

If you're been using the plastic ZC plates, you may have dis-remembered that the stock throat plate has a spring clip on the end closest to the front of the saw. Emulating that, perhaps using a modified cabinet door latch, might be one way to go.

Another possibility involves rare earth magnets. Since the BT's main table is aluminum, you'd have to have something for the magnet to stick to ... maybe steel screws threaded into the bosses in the throat plate recess, which would double as height adjusters. Epoxy the magnets to the TP in the appropriate locations and you're done.

I had thought of getting some of these magnet cups form Rockler:

http://www.rockler.com/product.cfm?p...&filter=magnet

And screwing one into each corner where the ZC plate screws in and place a magnet in it. Then I could glue metal washers into a recess made in the corners of the throat plates.

My concern is really getting the depth of the recess for the washer just right, so it is close enough to the magnet to be attracted, while also allowing the plate to remain flush with the top of the saw. But this is probably the best concept I've had so far.

My other idea was along the lines of those fasteners they use for speaker grills. I think they are called headlock fasteners. These have a head that compresses when you push it into a hole and holds via friction. If they had small enough ones that could go into the threaded holes for the zero-clearange plate, they may work. But I suspect that the threads would chew them up pretty fast. I think the magnets is a better idea.

[LarryG]

(I now see that you mentioned magnets yourself, in your OP. Missed that the first time I read it.)

My concern is really getting the depth of the recess for the washer just right, so it is close enough to the magnet to be attracted, while also allowing the plate to remain flush with the top of the saw.

I think you'd fershure want some height adjustment, which is why I'm thinking of attaching the magnet to the TP (epoxy, in a shallow counterbore) and letting it stick to the head of a flathead screw threaded into the main table. I'm nowhere near my BT so I can't recall how much vertical room there is to work with ... it might be necessary to drill and tap some new holes, if the stock locations wouldn't work.

Or you could do it the way you envision, with the magnet on the saw. Probably several variations of how the same basic idea could be executed.

[cgallery]

(I now see that you mentioned magnets yourself, in your OP. Missed that the first time I read it.)

I think you'd fershure want some height adjustment, which is why I'm thinking of attaching the magnet to the TP (epoxy, in a shallow counterbore) and letting it stick to the head of a flathead screw threaded into the main table.

...

Or you could do it the way you envision, with the magnet on the saw. Probably several variations of how the same basic idea could be executed.

The height adjustment using the TP screws has been a little bit of a problem for me. With what amounts to support in the four corners only, the plates I have tested (3/8" BB) flexed when I pushed down on them.

They seem to either need to be thicker than 3/8", or contact the 3/32" ledge on the long sides of the opening for proper support.

Thanks, BTW, for all the ideas.

[LCHIEN]

So has anyone figured out a way to make BT3000 throat plates that don't require screwing-on?

Maybe not exactly what you had in mind - but instead of the 3/4" long screws supplied withthe saw and ZCTPs, perhaps you could go to 10-24 x 3/8" FH machine screws. These would be a lot faster to put in tho not do away with screwdriver jockeying altogether.

I see no need for the screws to be as long as the ones they supply. The TP is only about 3/16" thick or so at the screw holes.

[cgallery]

Maybe not exactly what you had in mind - but instead of the 3/4" long screws supplied withthe saw and ZCTPs, perhaps you could go to 10-24 x 3/8" FH machine screws. These would be a lot faster to put in tho not do away with screwdriver jockeying altogether.

I see no need for the screws to be as long as the ones they supply. The TP is only about 3/16" thick or so at the screw holes.

If I don't figure this out soon I'm going to be using 3/8" long nylon 10-24 flat-head screws. Nylon because I'm worried about stripping the aluminum top with repeated TP changes.

What I'd really like is one of those Nahm-type inserts, where they use replaceable strips about 1/4" thick and 1" wide. The main component looks to be machined aluminum, and has a dovetailed way for the sacrificial insert.

If I could figure something out I'd have it made. You could probably have qty. 50 of something similar made at eMachineShop for about $35 to $45 a whack. I'm sure at least fifty people here would step forward and take my surplus. But the design is the stumbing block (of course).

[LCHIEN]

phil, I can understand about the wear on the aluminum table top thread-ed holes.

I generally use a hand-turned screwdriver and put them in gently. I don't think a great deal of force is necessary to seat them fully nor is there much force trying to back them out or vibrate them loose. So "easy does it" will extend the life of the threads for a long time.

[Thalermade]

A long, long, time ago a man named Lee made and sold quick release throat plates. Didn't see them on the website, maybe he still has the info and plans stored somewhere.

http://www.leestyron.com/default.php

If I get a chance this weekend I will take a picture and post it.

have fun and be safe
Russ

[Thom2]

geesh, never checked this thread because I figured one of the old timers would point right to Lee .... these guys are slippin' ('cept for Russ )

Here it is ....

http://www.leestyron.com/zctp_plans.php

Lee doesn't sell them anymore but he's still got the plans up

[Russianwolf]

You guys are over thinking this


Carpet tape.


Couple little pieces on the bottom where they will contact the supports and viola.

cheap, easy and replacable.