Zero clearance insert questions

[George Hoppen]

I have a number of questions about zero clearance inserts for my table saw. A year ago I bought a piece of 1/2" thick phenolic to make several inserts for my 1992 Delta table saw. Well, as luck would have it, I didn't get to it and the motor on saw took a digger recently, and fortunately I hadn't made any inserts yet. Since the motor has the arbor integral and is $250, I convinced my wife it wasn't worth the cost and she let me buy a new saw! She's the best! Here are my questions:
1) I have a Jet JWSS-10LFR saw. The insert included with the saw is 3/8" thick with set screw levelers. The supports for the inserts are 1/2" below top of table. So I really need 7/16" or 3/8" thick phenolic to allow vertical adjustment. Can I put the phenolic through my planer to reduce its thickness without ruining the planer blades?
2) On after-market inserts I have noticed that they have a "gouge" on the underside as the start of the blade slot. What does this do and is this necessary?
3) What type of drill bit is needed to drill into the phenolic. Rockler has what they are calling a special bit w/countersink to drill phenolic (and it doesn't wander) for $19. Is that really necessary?
4) Leveling set screws - will they cut their own threads in the phenolic or should the holes be tapped first?

Thanks in advance for the help!

[glenn bradley]

1) I have a Jet JWSS-10LFR saw. The insert included with the saw is 3/8" thick with set screw levelers. The supports for the inserts are 1/2" below top of table. So I really need 7/16" or 3/8" thick phenolic to allow vertical adjustment. Can I put the phenolic through my planer to reduce its thickness without ruining the planer blades?

- I cannot comment on this but hope someone who knows, will.

2) On after-market inserts I have noticed that they have a "gouge" on the underside as the start of the blade slot. What does this do and is this necessary?

- Most saws only bring the blade a small amount below the table in the lower most position. The gouge allows you to turn the saw on (with your insert firmly attached to the saw via screw or other method) and raise the blade to get the zero clearance cut you are after. If you don't want to fool with making the gouge and if (very rare) you have a smaller diameter blade that is not wider than your actual blade, use that. If you are running full kerf blades, an outside dado stack plate can do the job. I cut the "gouge" on my router table.

3) What type of drill bit is needed to drill into the phenolic. Rockler has what they are calling a special bit w/countersink to drill phenolic (and it doesn't wander) for $19. Is that really necessary?

- I have never used a "special" bit for phenolic, no problems.

4) Leveling set screws - will they cut their own threads in the phenolic or should the holes be tapped first?

- Phenolic will accept threading well. I use 1/2" BB ply and just thread them in. You could drill a hole in one of the corners you are going to cut off of your blanks and try it.

[Chris Kennedy]

I have a number of questions about zero clearance inserts for my table saw. A year ago I bought a piece of 1/2" thick phenolic to make several inserts for my 1992 Delta table saw. Well, as luck would have it, I didn't get to it and the motor on saw took a digger recently, and fortunately I hadn't made any inserts yet. Since the motor has the arbor integral and is $250, I convinced my wife it wasn't worth the cost and she let me buy a new saw! She's the best! Here are my questions:
1) I have a Jet JWSS-10LFR saw. The insert included with the saw is 3/8" thick with set screw levelers. The supports for the inserts are 1/2" below top of table. So I really need 7/16" or 3/8" thick phenolic to allow vertical adjustment. Can I put the phenolic through my planer to reduce its thickness without ruining the planer blades?
2) On after-market inserts I have noticed that they have a "gouge" on the underside as the start of the blade slot. What does this do and is this necessary?
3) What type of drill bit is needed to drill into the phenolic. Rockler has what they are calling a special bit w/countersink to drill phenolic (and it doesn't wander) for $19. Is that really necessary?
4) Leveling set screws - will they cut their own threads in the phenolic or should the holes be tapped first?

Thanks in advance for the help!


I can provide some partial answer. The disclaimer -- I have only worked with phenolic once, and it was miserable. The stuff is hard!

1. I wouldn't put it through my planer. I have never tried, and maybe in theory you can, but I wouldn't.

2. The gouge is so there is room for the blade when it is completely below the table. If you don't want to route the gouge, you may be able to get away with using a smaller diameter blade to begin the cut (dado blade or circ saw blade maybe).

3. I drilled my phenolic with zinc nitride coated bits. They did just fine.

4. I would recommend tapping the holes. I didn't, and I probably broke ever other screw I was putting in.

Hope that helps.

Cheers,

Chris

[Myk Rian]

You can always create a rabbet around the edge where the insert is too thick. A router table does that fine.

Use a smaller blade to start the slot. Then switch over to the 10" to finish it.

[George Hoppen]

Thanks - all make sense and are a big help!

[John Thompson]

Do the rabbit as Myk suggested. Phenolic is nasty on planer or jointer blades period and I mean nasty.

[Bill Huber]

Look at the last post in this thread, the pictures are the inserts for my Jet contractor saw and they are 1/2" phenolic and that is the only thing I use for them.
They last forever and work very well.

http://www.sawmillcreek.org/showthread.php?t=108137&highlight=clear