 |
LeeWay Workshop |
January 05, 2009 |
 |
| This blade
guard is designed to fit the Ryobi BT3000, BT3100 and the Craftsman
22811N table saws. The guard itself is made from clear 3/16" thick
polycarbonate and is very durable. I use dado and rabbet joints for the
main structure
and they are welded with solvent type adhesive. The clamp is an integral
part of this blade guard along with the shark splitter that
I use for non-through cuts. It clamps to the very top of this splitter.
This
means that the guard takes up very little (3/8") of the blade
height. The clamp is locked on the splitter by turning the 2 knobs.
The guard
is then just slipped into place using no fasteners. It collects saw
dust very well with a ZCTP and even better with the standard OEM
throat plate.
This includes MDF dust and it virtually eliminates any dust in
the air. You do still get some dust at the very end of the cut, but nothing
like
without this guard, and none of the finer dust associated with
MDF. |
| These plans and fabricating instructions contain links to my parts sources.
Other dealers may give better pricing for some things,
but these are the best that I have found. You also have to add shipping
to these prices. I can get some of these parts locally, but not as cheap as online, even
figuring in the cost of shipping.
|
This is a thumbnail of the actual template for the sides of the Shark
Guard. Just print it out at 300 dpi and the scale should read exactly
1". Cut it apart and make a wooden pattern out of 3/4" plywood
or MDF. You can work on this template while your supplies are arriving.
Click on the image to see the template.
|
 |
|
Here is a link to a
PDF
of the outline for the 8.0 and the 8.4 model Sharks. The same basic building applies to these. There are some differences and I hope to be able to get these posted as I get them completed. If you are intending to build one, contact me to see how far along I am with these plans.The main differences are the length of the guard and the rear or tail hook. The earlier version only fits the Ryobi's and some Craftsman's. The 8.0's are designed to fit all 10" models. It is simply a better design.
|
The Shark Guard Parts
Lets start with the Shark Guard first. Trace a left and a
right side outline on the polycarbonate sheet (Parts A and B). Lay these
out fairly
close to within 3/8" of each other. This should provide the least amount of waste. You will need a couple more
parts from this sheet.
You can cut this out now using a bandsaw or jigsaw and skip this next step. You will need to do some sanding though, if you choose the sawing method.
I rough cut the sides using a bandsaw or jigsaw
to within 1/4" of the line. I use regular craft style hot glue and
I use 3 dabs per side to attach the sides to the template. You could
choose to use double stick tape here too. If I use the polycarbonate
with a paper coating, I just hot glue the template with that left on it only.
If my polycarbonate has a plastic protective coating, I add some painter's
tape to the polycarb and apply the hot glue on this. I don't want the hot glue to melt
the plastic protector and damage the polycarbonate underneath. When you
have the sides stuck to the template, it should look something like this
next image on the right.
|
|
 |
Routing the Template
|
I use a trim router and a laminate trim bit with a bearing that is
3/8" around. This allows the bit to cut into the slots as well
as trim the outside on both parts. Be careful and go slow, especially
in the slots. The next pic shows the next step. With both sides still
attached to the template, I move to the router table and use the 1/8" roundover
bit with bearing. I rout all the way around, but not in the slots.
Also, be careful by the rear slots. This part is not very wide. I usually
round this with a file. You could simply cut the sides out using a
bandsaw or a jigsaw and then just sand the parts smooth to the template
line. This may even be easier than using the router method.
|
The Top Rabbet
| Using the printout of the template, mark the beginning point and
the ending point of the long rabbet on top. Once both sides are
rounded over and marked, you can pull the polycarbonate off the
template.
I
change the bit in the router table to the 3/16" straight cutting
bit. I use a simple sacrificial fence and mark on it the start and
end points of the bit. I line these up with the marks I made from the
template. The bit is set about 1/32" or less away from this fence
and the height is just over 1/16" deep. A perfect sized cut
is too perfect and doesn't allow the glue to flow in the joint.
I make
one pass on the fence and come back and finish the remaining outside
ridge with a freehand pass. I do this to both pieces. The front
location of the rabbet is the most critical. This is the one I
use to line up
the top (part C) when I start welding it together.
|
39 Degree Dado
 |
The next step is to cut the 39-degree dado for the front portion of
the blade cover (part D). I don't change the bit height for this. It
is still just a hair over 1/16" deep. The only way that I have found
how to do this is to make a jig to use on the router table. The jig that
I made slides along the fence on the BT3100, but you could run it in
a miter or a t-track slot as well. It simply just holds the two sides
at a 39-degree angle and cuts a dado all the way from the top to the
bottom of the sides. |
| Take a look at jig in these two images. Both of the angles
were cut at 39-degrees and then mounted opposite each other to form the v-shaped jig. I just used screws as stops to help position the sides.
I suggest a couple of practice cuts using some 1/4" plywood parts
cut in the same shape as the sides to insure a properly made jig. You
need the dado for both sides to match exactly with each other. A hair
forward or back from the template isn't as critical as getting the sides
to match each other. You need to reset the jig to cut these dados again
to make the slots about a 1/32" wider than the 3/16" stock.
You have to make room for the glue to flow. A little too big on these
dados is better than too tight.
|
 |
The Other Parts
Now you need to cut a couple of strips of polycarbonate from
the rest of your stock. I would suggest a blade with the most
teeth
that you
have available for the tablesaw. Use hold-downs if possible. Use a
push stick or push shoe. It is critical to keep the polycarb from bouncing
during the cutting procedure. If a tooth snags on it, it can snap and
pop and scare the crap out of you. You might choose to hot glue the
polycarb to a scrap strip of wood and make these rip cuts with the
plastic on the bottom of this scrap. The width needs to be 1 13/16" wide.
This is a critical dimension.
This width and the depth of the dados on the side determine the interior dimension of the guard. It needs to be precise to mount correctly on the clamp.
You need one part for the top, (Part C) 15 3/8" long. You need
another part, front plate, (Part D) to have a 39 degree bevel cut on
the top side and a 31 degree cut on the bottom edge. You should make
this a 1/16" or so shorter than the actual length of the dado
on the sides. The length from short point (39-degree) to long point
(31 degree) on the front of this piece is 5 1/4". Your dado may
be a bit shorter or longer. Adjust that length dimension to fit your
slot. You need one more part that has a 31 degree angle cut on one
end and 90 on the other (Part E).This tiny part gets butt welded in
place. It is typically 1 11/16" wide and 3/4" long at the
short point. See the template for proper placement.
Sand the front and rear of the top part to fit into the rounded ends of the rabbets
on the sides. Take a file and knock off the square edges on all the
parts that will be welded. This helps with the solvent flow. Now we
are ready to weld. Check
out this link for some advice on the particulars in working and gluing
polycarbonate.
|
|
The Glueing (welding)
|
Remove the protective film from all the parts. I didn't actually glue
these together for the pics. You don't want to be fooling around too
much when you are gluing these up. I start with one side and part D.
|
|
 |
Shoot some glue in the dado from the top edge. You can see where the
glue is going. If you put too much in, you will have a mess. If it
drips over the edge, you will have a mess. Let it set for a couple
minutes. |
| It's nearly an instant bond, but not quite. Take a square
and make sure the part is square with the side. Flip the part around
and glue from the bottom in the same manner. Then fill in on both
sides of the dado. Try not to leave any air pockets, but a couple
of small
ones shouldn't affect the strength of the joint. Let this set about
5 minutes or so. |
|
 |
Take the top part (C) and place it in the rabbet.
Don't glue it yet. Now take the other side and place it on where
it goes. Carefully turn it over and with everything positioned
correctly,
shoot a little solvent in the dado at the bottom again. Let this
set a few minutes.
Now swing out the top part to access the top of the dado on that side.
Leave the rear of the top part in the rabbet for spacing. Shoot some
solvent in the dado. When dry again, replace the top back in the rabbet.
Line it up with both sides at the front of the rabbet. Hold upside
down and shoot a bead in the joint about 1" long at all 4 corners.
Let the joint dry a little between each injection. Blowing on it while
you are waiting seems to help. Now it should be getting pretty solid
feeling. Make sure at this point that all is square again. A slight
adjustment is still possible. Now taking your time, go back and fill
in all the beads that haven't been glued up. Not too much solvent.
It will run out of the joint. If the solvent touches the polycarb anywhere
its not supposed to, it will show badly. Now you let it dry a few hours
to get good and rigid and insure all the solvent is dry.
|
Drilling for the Dust Port
Now you can drill the hole in the top to accept the dust port. I use
a 2" Forstner bit to bore this hole. You can use a holesaw too.
The hole is centered in the middle and as near the front part (D) as
possible. I only drill deep enough to cut through the top part (C). You
are cutting into the sides too and this is why a forstner bit is better
than a holesaw. You will have some trimming to do with a holesaw. The dust port will replace the portion of the sides that you remove. I clean
up the edge of the hole and glue in a length of dust port using the glue
in the tube. This effectively seals the port onto the Shark Guard. It can be done with the syringe, but very slow and carefully. You will need a couple of applications this way. You have to let it dry between applications so that it doesn't run all over the guard.
I let this dry for about 30 minutes and then I use the syringe on the inside
and finish welding the joint. The glue in the tube is not as strong as
the plain solvent type. I usually add the decals after I clean it up
real good with a soft cloth and a squirt of Windex. I found that the plastic
cleaner that I ordered leaves a film.
Lastly, weld in part E. You now have a Shark Guard. You have to mount
it so the clamp mount is next.
|
The Clamp Assembly
| Compared to the Shark Guard, the clamp assembly is a breeze. This graphic is basically self-explanatory. The other pic is the finished
clamp and what it should look like. |
 |
|
|
Start by cutting your aluminum tube to 5". You need 2 this length.
You need to drill the holes as close to perfect as you can get. I drill
a pilot hole about 1/8" first in one half of the clamp. Then I drill
the 2 1/4" holes here. Now I clamp the two parts together and drill
both holes in the second half of the clamp. Leave these clamped together
and change drill bits to the large one (25/64"). Drill these 4 holes
through the outside part of the tube only. This leaves you with 1/4" holes
on one side of the tube and just over 3/8" on the other side. Clean
up all the milling fragments with a file and I use a wire wheel to put
a brushed finish on these parts.
|
| Now on one side, its time to glue some
60, 80, or 100 grit sandpaper to one half on the 1/4" hole side
or inside. I use contact adhesive and a small acid brush. Put glue on
the aluminum and the backing of the sandpaper. Let these tack up. Stick
them together and trim the outside edges and poke a hole back through
where the 1/4" hole is. You are now ready to thread the hardware.
Put a washer and a bushing on one screw and thread it through. Put
another bushing and washer and then the knob on the other side and
you have a
clamp. I always line the clamp up with the rear of the splitter.
You may need to check that the blade doesn't contact part E when
raised
fully and the Shark Guard is in place. Feel free to e-mail me with
any questions
or comments.
|
| Now after seeing the plans, if you are interested in purchasing a Shark
Guard and clamp from me, click here for details. |
|
|
HOME
MY
SHOP
