Zero Clearance Inserts (ZCI)

dusty · Post by **dusty** » Thu Jan 24, 2013 2:40 pm

Based on my own limited exposure to only three different Mark V tables, I believe you will find that a 1/4" thick insert will be very, very close to perfectly flush with the table top.

As has been stated, if too thin, they can always be shimmed but why do that if you are making them. Make them thick enough to not need the shim. If too thick, you can either discard them (as has been suggested) or make them thinner.

I have had more trouble getting the holes in the right place than in getting them the right thickness. Now that I built my zci sled, I don't have that problem either.

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Gene Howe · Post by **Gene Howe** » Thu Jan 24, 2013 5:12 pm

If they aren't quite flush (too low) apply a few dollops of hot melt glue on the metal ledge/lip and immediately drop the insert in and push it down till level. The glue will stick to the wood and come away cleanly from the metal.....at least, that's my experience.

mrhart · Post by **mrhart** » Fri Jan 25, 2013 9:36 am

dusty wrote:Based on my own limited exposure to only three different Mark V tables, I believe you will find that a 1/4" thick insert will be very, very close to perfectly flush with the table top.

As has been stated, if too thin, they can always be shimmed but why do that if you are making them. Make them thick enough to not need the shim. If too thick, you can either discard them (as has been suggested) or make them thinner.

I have had more trouble getting the holes in the right place than in getting them the right thickness. Now that I built my zci sled, I don't have that problem either.

[ATTACH]20012[/ATTACH]

So back to basics sir. I have'nt made one yet but I need to asap as I've had issues where I "should" have had one in.
Thickness of 1/4" will be fine.
I can trace the shape from the SS one.
Drill and countersink the holes.
Everone mentions 1/4" hardboard, I haven't seen that in the stores. I ve seen some "hardboard" thats dark brown with a white laminate on one side, but it's not that thick. I bought some to make patterns with, works good but it's kinda soft and leaves fuzzy edges when you cut it.
Any pics of real hard board?

heathicus · Post by **heathicus** » Fri Jan 25, 2013 9:51 am

What is generally referred to as hardboard is labeled "Eucaboard" at my local Lowes.

pennview · Post by **pennview** » Fri Jan 25, 2013 9:57 am

Masonite is another brand name for hardboard.

dusty · Post by **dusty** » Fri Jan 25, 2013 10:05 am

heathicus wrote:What is generally referred to as hardboard is labeled "Eucaboard" at my local Lowes.

I think 1/4" eucaboard measures 3/16". Not a big deal for most applications but not good for TS inserts (IMHO).

dusty · Post by **dusty** » Fri Jan 25, 2013 10:14 am

mrhart wrote:So back to basics sir. I have'nt made one yet but I need to asap as I've had issues where I "should" have had one in.
Thickness of 1/4" will be fine.
I can trace the shape from the SS one.
Drill and countersink the holes.
Everone mentions 1/4" hardboard, I haven't seen that in the stores. I ve seen some "hardboard" thats dark brown with a white laminate on one side, but it's not that thick. I bought some to make patterns with, works good but it's kinda soft and leaves fuzzy edges when you cut it.
Any pics of real hard board?

Neither of these are "real hardboard" (used to be called masonite and was waffled on one side while slick on the other).

The darker one is actually a 3 layer laminate and is .004" thinner than I would like. The other is 1/4" thick but is not as stiff as I would like.

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The lighter colored one is what I have been using until recently. I have begun an evaluation, however, using real wood. What is in test right now are a couple made from cherry cutoffs that I planed to a precise 1/2" and routed to fit snugly in the cut out.

Ed in Tampa · Post by **Ed in Tampa** » Fri Jan 25, 2013 10:51 am

dusty wrote:Neither of these are "real hardboard" (used to be called masonite and was waffled on one side while slick on the other).

The darker one is actually a 3 layer laminate and is .004" thinner than I would like. The other is 1/4" thick but is not as stiff as I would like.

[ATTACH]20034[/ATTACH]

The lighter colored one is what I have been using until recently. I have begun an evaluation, however, using real wood. What is in test right now are a couple made from cherry cutoffs that I planed to a precise 1/2" and routed to fit snugly in the cut out.

The one on the right the lighter one looks like 1/4 MDF to me.

I suspect Masonite had chemicals in it that the EPA had on their hit list (read formaldehyde) and Masonite was allowed to die a quiet death.

Also I think building techniques have changed where Masonite isn't used as it once was.

I still see peg board but even that is being replaced with the new "track" systems.

pennview · Post by **pennview** » Fri Jan 25, 2013 11:33 am

I thought I found the stuff at the Home Depot web site. They list 2' x 4' panels of tempered hardboard that is 1/4" thick, but the fine print in the product description says it's actually 3/16" thick.

I have a ZCI made of laminate flooring that is about 8mm thick for my Model 500, but I haven't gotten around to routing around the edges so it's even with the surface of the table. I also made a round one for the bandsaw, but that too needs routing.