hollow chisel bit not fitting well

[mr_skittle]

I recently got the Premium 5/8in hollow chisel mortiser bit from Lee Valley and as I'm getting it set up I realize the shaft of the chisel portion doesn't fit tight enough into the collar on my machine. I checked the best I could with a feeler gauge and it looks to be about .005in too small. Doesn't seem like much but it's enough to throw things off. When I tighten the set screw on the machine to lock the chisel in place, it causes it to tilt sideways just enough to make the drill bit really rub on the inside of the chisel. 

The machine is a Delta bench-top mortiser, and while it's a bit old, it hasn't seen much use. I have other bits that fit well, including the economy 1/4 one from Lee Valley. I did call customer service and they said just to send it back, but I thought I'd check here on WN for any ideas before I do so. If in fact I need to return it, does anyone have suggestions for other premium brands that make a 5/8in bit? I tried a cheap one off Amazon and it's a POS.

[jstraw]

I’ve had good luck with Fisch bits. They get good reviews. They’re made in Austria. I got mine from Tools For Working Wood, but they also can be found through Woodcraft and Amazon.

[mr_skittle]

I’ve had good luck with Fisch bits.  They get good reviews. They’re made in Austria.  I got mine from Tools For Working Wood, but they also can be found through Woodcraft and Amazon.

Funny you should mention Fisch. I was at ACME Tools getting a few dust collection fittings and asked if they carry any bits. Nothing on hand but they can order Fisch. I'd never heard of the brand myself but was encouraged when I saw the country of origin. I'm going to attempt to shim the one I've got and see if I can get anywhere but I'm not holding my breath. With only .005 of slop on a round surface, I'm not sure how. I'm thinking tin foil might be somewhere to start.

[Maple Leaf]

Your first move should be to call Lee Valley. They wrote the book on customer service. 

I had a professor in college; he was Swiss. In response to a question about legendary Swiss punctuality he was fond of proclaiming, "If you are on a European train, and it isn't running on time, you are either not on a Swiss train, or you do not have a Swiss watch. My first guess is that either the chisel is not to spec or your mortiser isn't. 

Either way call LV. They're really good.


dp

[Tapper]

Your first move should be to call Lee Valley. They wrote the book on customer service. 

I had a professor in college; he was Swiss. In response to a question about legendary Swiss punctuality he was fond of proclaiming, "If you are on a European train, and it isn't running on time, you are either not on a Swiss train, or you do not have a Swiss watch. My first guess is that either the chisel is not to spec or your mortiser isn't. 

Either way call LV. They're really good.


dp

^^^^^^^^^^^^
Ditto!!!

Doug

[mr_skittle]

I mentioned in the original post that I did contact Lee Valley. I've understood their customer service to be excellent but the rep I talked with wasn't particularly insightful. He pretty much said just to send it back. I pried a bit about whether or not the .005in was within the tolerance allowed by the manufacturer but he had nothing for me. I wouldn't say he was rude, but I wouldn't say he was friendly either. I could always call back and hope I get someone else.

[jteneyck]

If you don't absolutely need to make square ended mortises just set that thing in the corner and build/buy one of my horizontal router mortisers or buy a Domino.  You will thank me a hundred times over which ever way you go.  

Hollow chisels mortisers were state of the art in uh, when was  it, oh yeah 150 years ago.  So was the horse and buggy.  

John

[mr_skittle]

Here's a  post from a different thread that explains what I'm using the mortiser for. It's a design element of the piece. I won't argue that there are lots of ways to do mortises or that a mortiser machine is the best, but in this case, I'm compelled to make it work. 



I’d like to spend some time now covering how I’m punching the hole for the handle. I was pretty sure that I was going to use my mortiser machine, but I didn’t have the appropriate bit when I was working on the model. I just went with the time-tested method of a forsner bit and a sharp chisel, but I knew this was not a sustainable way to batch them out. After spending what seemed like WAY too long finding the right mortiser bit I started to think about how to make the drill press/chisel method more efficient. 

Quick aside on the search for a bit
I have an older Delta benchtop mortiser that only accepts 5/8in shaft bit. Turns out that most bits are not 5/8. In addition, I also wanted to get a more middle of the road bit when it comes to quality. Amazon has sooo many different choices but when you are looking for anything over ½ in the pickings get slim. Either they were of extremely questionable quality or didn’t have the right size shaft. I was originally looking for 3/4 in but when the search wasn’t going my way so I started looking at 5/8in. I finally found one from Woodline, with the right size shaft, for about $25. I can’t say I’m impressed with the quality but after lots of sharpening, it's serviceable. Sharpening the inside of a bit over ½ is really a pain. The little diamond cones don’t fit! This whole story explains why I need to figure out if and how to get a 4 shouldered tenon on the handle. 

To get back on track, let's talk about my failed attempt at a jig for finished the mortise. The ideas is to come up with a way to punch the hole without having to lay it out. For my first attempt, I tacked a few cleats onto a piece of plywood to hold the side in place while I squared up the hole from the forsner bit. Then I fastened a piece of oak over the cleats and with a nice square guide hole directly above the hole in the handle. My thinking was that I could use the oak board to help guide my chisel and shave some time off the process. It didn’t work out well enough. I’d likely be easier just to do it without the guide. I had already taken the guide apart so the picture is just a mock-up to give the idea. 


    

I think I will at least be able to salvage the plywood and cleats setup to use on the mortiser. I’ll just fasten it down to the table of the machine and center it under the bit. This is what I envisioned from the start but it took longer than I'd have liked to finally get here. And let me say this, Using this mortiser for 5/8in holes is no treat. Even after tuning up the chisel and bit, you really have to pull on that handle. 


    

[jteneyck]

Yeah, a 5/8" square hole is beyond the comfort zone with a bench top mortiser in oak.  I think you need to predrill or route out most of the waste first in order for the mortiser to work more easily.  Or get a floor model mortiser.  Or, better still, get a Makka.  

John

[jteneyck]

But not everyone has a $1000 plus laying around for another tool....

I agree.  But you can build my horizontal router mortiser from the free plans I offer for around $100 plus a router (that most folks already have).  


John