Shop Made Zero Clearance Inserts for Bosch 4100

  • Advertise with us
Project by NiteWalker posted 04-05-2013 02:46 PM 7720 views 11 times favorited 4 comments Add to Favorites Watch

After getting my bosch 4100 refurb and setting it up, the first thing I did after making the stand for it, was make some zero clearance inserts for it. These are actually take 2; the first inserts I made out of baltic birch plywood scraps and they weren’t completely flat, so I had a corner that stuck up and was catching on workpieces. So this time I used some 7/16” MDF I had.

The process wasn’t too complicated, just a few more steps involved than a typical zci. The first thing I did was cut a blank for a master template. I cut it so it’s a snug fit. Instead of using the stock insert as a template, I used one of the corners to make a custom corner radius template like the other one I made. This works better for me than using the stock insert and having to reposition it because of the gaps and tabs in the way. Once the master template was done I used it at the router table with a flush trim bit to make the rest.

With the fit taken care of, I drilled the holes for finger hole and set screws. For the finger hole I used an old 24mm forstner (a size I use a lot) and placed it out of the way of the blade slot and leveling screw locations. For the set screws I just screwed the set screws in most of the way on the stock insert, placed it over the blanks and gave it a tap. This left indentations so I knew where to drill the holes for the set screws. I used 1/4-20×3/8” flat tipped set screws from amazon. I already have a 1/4-20 tap set, but instead of using the drill bit that came with it I used one 1/16” smaller so the set screws would have a snug fit. Since MDF is so soft, using the tap with the smaller hole was no problem. Also, instead of tapping by hand, I used my cordless drill on slow speed. I’ve been tapping holes in wood this way for a while and it works great.

A rabbet all the way around was done at the router table. It’s about 1/8” deep and just over 5/8” wide I think. On the left side I had to do another deeper, but not as wide, rabbet for the ledge that’s on the saw. I used stops at the router table for this rabbet.

For the blade slot I used a dado set to get it started, then switched to the blade I use (great blades btw). To make sure the slot was long enough for the riving knife, I used a 1/8” spiral bit at the router table. I used the slot I already made at the table saw to position the fence, and stops for the start and end positions of the cut.

With all the woodwork out of the way I gave the top edges a light sanding and applied 2 coats of zinsser sealcoat, followed by a light sanding with 400 grit and a coat of paste wax.

Time to put em to work!

-- He who dies with the most tools... dies with the emptiest wallet.

4 comments so far

View mariva57's profile


666 posts in 3166 days

#1 posted 04-05-2013 08:48 PM

Zero Clearance Inserts, will be very useful. Instead I have a
Bosch GTS10.

-- The common man thinks. The wise man is silent. The stupid man discusses.

View whitebeast88's profile


4128 posts in 3352 days

#2 posted 04-05-2013 09:07 PM

nice work,thinking on trying some for my r4512 ridgid.

-- Marty.Athens,AL

View NiteWalker's profile


2743 posts in 3739 days

#3 posted 04-06-2013 05:18 AM

Thanks guys. They work great; the sealcoat/wax combo keeps the inserts amazingly smooth and the MDF makes for a great insert material.

-- He who dies with the most tools... dies with the emptiest wallet.

View jshroyer's profile


80 posts in 2820 days

#4 posted 09-30-2014 06:28 PM

that is very helpful. I also have a bosch and need a ZCI for it.

I didnt think of using a template. I think i might just use the dado or original one and then put a few layers of tape around it to add thickness. Then use a router follower bit.

I have a couple questions about this. Where do you get 7/16” MDF? i dont think i have seen that before. i only ever see 1/2”.

Also i do like how you made this. It worked pretty well to make that.


Have your say...

You must be signed in to post the comments.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics