Bosch Fixed Base Design Flaw

[Bob Penoyer]

I have a Bosch RA1181 router table. I'm using the fixed base of my MRC23EVSK router in the table.

The Bosch fixed base (MRF01) has a design flaw, I think. I wonder about the best way to deal with it.

With the fixed base mounted upside down under the table's top, the router motor placed in the mount, and the clamping lever loosened, all of the weight of the motor is supported by the retaining snap ring (e-clip) attached to the adjustment shaft. This is a very weak mechanism.

The retaining clip (e-clip) is held in the adjustment shaft by a shallow groove in the shaft. When the shaft is turned to adjust bit height, the ring can--and does--slip out of the groove so support of the motor is lost.

Has anyone else run into this problem? Did you find a way to avoid this weakness?

[Leon]

Not a design flaw, you are simply using a router that was intended to be used in the traditional manner, not upside down. so you have to be careful to not damage the router.

What you should be using is one of these.

or any of these

Or use the plunge base for that router.

[woodchucker]

I don't have that router, I have 2 of the 1617evs. But I wonder if you can add a drop of C/A to the circlip or eclip . First take it apart and wax the area where the circlip or eclip rubs against so it won't glue to that area. you can also use oil, but if you drop the clip into it, it defeats the purpose. use a heavy coating of wax as c/a will still burn though, or better yet, use waxpaper.

put the clip on, and drop the c/a on the clip and rod.. really just a drop.

If you even need to take it apart, a torch or soldering iron will help you losen it.

That should help hold it.

I looked at that router, seemed way heavier than my 1617evs. Other than that issue , how do you like it.

[Bob Penoyer]

Well, I'm using a Bosch router motor with a Bosch fixed base in a Bosch router table. Certainly, the Bosch engineers must have realized, when they designed and marketed their router table, that their motor and base would be used in the table. It's shown used that way on p.23 of this manual:

It's clear to me that the base was not designed to be used upside down as it is in the router table. For that reason, I have to label the weakness that I described as a design flaw.

I will give these two links a careful review but I'd rather not have to buy additional equipment.

That would be a problem. I use the plunge base fairly often and wouldn't want to have to remove and reinstall it in the table. The fixed base is permanently installed in the table since I haven't needed it for any other reason. Also, since the base is spring loaded, it would be awkward to use upside down under the table.

[Bob Penoyer]

Rather than the c/a, I was thinking that a small (small!) hose clamp might be used around the adjustment shaft to backup the clip. It's only a thought at this point since I haven't studied the idea yet.

I think my router and the 1617 are in the same class with the 1617 being an older model. With the exception of the problem we're discussing, I think the 23EVS router is excellent. The feature I like most is the on-handle power switch.

[Electric Comet]

if you plan to keep it then you should contact bosch if it is possible some places have so many layers that you never get any traction

meanwhile i would not use it as it is because it sounds like the bad kind of surprise waiting to happen

it is possible that the designer of the table was not thoughtful enough and also was not in contact with the designer of the router

[Bob Penoyer]

I do plan to keep it. The only "surprise" occurs when adjusting bit height from above the top of the table: the e-clip can slip out of the groove on the adjustment shaft and prevent the motor from being raised. Everything is safe once the base clamp lever is engaged.

I've come up with a fix. I wrapped some plastic material around the

1/4" adjustment shaft (to increase the diameter) and against the clip, then tightened a small hose clamp (minimum 5/16" diameter) around the plastic. This seems to work. The arrangement is secure on the shaft and the clamp doesn't interfere with the motor or anything else. That's good, but there's a better idea.

A better fix is to place a T-nut big enough to just slip over the 1/4" adjustment shaft (5/16"?) and use the hose clamp and plastic to hold it in place. This way the flange of the T-nut rides against the base flange that the clip rides against. I haven't tried it yet but I think this is a better way.

[Bob Penoyer]

I'm adding this post for anyone interested or anyone who has run into the same problem. I've implemented a fix that has worked for me.

After removing the e-ring, I drilled out the threads of a 1/4" T-nut using a 1/4" drill, then slipped the T-nut over the threaded shaft.

With the shaft correctly mounted in the base and the flange of the T-nut against the flange that the e-ring rested against, scratch a mark around the shaft where the other end of the T-nut sleeve meets the shaft.

Now remove the shaft and the T-nut from the base.

Using my drill with a diamond cutting wheel (a few bucks for the wheel from Harbor Freight), cut a groove around the shaft. Let the groove extend from about 1/16" above the scratch mark to about 1/16" below it. Cut the depth of the groove so that the final diameter of the groove is about half the diameter of the shaft.

Using some abrasive, such as sandpaper, abrade the surface of the shaft to roughen it.

Clean the shaft and the T-nut with acetone to remove all oils and grease.

Assemble the shaft and T-nut back onto the base. When the shaft and T-nut are seated properly, the sleeve of the T-nut should extend about half-way across the width of the new groove. The other half of the groove should be exposed.

Mix a two-part, 5-minute epoxy. Glop the epoxy onto the end of the T-nut sleeve and into the groove on the shaft, being sure to get epoxy completely into the groove, up under the end of the T-nut sleeve. Be generous with the epoxy. Spread it thickly, including over the end of the T-nut sleeve and on the shaft beyond the groove.

Patiently watch the assembly after the epoxy has been applied. Prevent the epoxy from forming a drip on one side or wetting down the inside of the T-nut sleeve. You don't want to epoxy the T-nut to the router base, only the threaded shaft. If you've used 5-minute epoxy, it should stiffen fairly quickly. Once that happens, allow at least 24 hours for the epoxy to cure.

The threaded shaft should now be held securely in the fixed base and the router lift feature should work reliably.

[gsaksida]

Dne petek, 06. maj 2016 03.37.39 UTC+2 je oseba Bob Penoyer napisala:

Can you please post some pics? I am planing to buy this router although I am aware of this problem (I have already fsn OFA and guide rail system that is why).

[Bob Penoyer]

No pics. But a better idea than what I described here last year is to use a drill bit stop collar in place of the e-clip.