Mortiser Bit nightmare


I recently posted a topic on setting up a mortiser and the bit. As for as I can tell everything is tuned as best an I can get it. The problem is that I just can't believe the performance I'm getting is normal.
I have to use damn gorilla strength to get through QS white oak and on some test cuts it started smoking heavily on the first cut. It seems as though the bit is just crap but its right out of the box and I tuned it up as per a FWW article I just read. I don't know what brand the bit is which makes me question it right off. The only other thing I can think is the bit chisel clearence. I spaced it about 3/16 and it was horrible and an 1/8" seemed a little better but it feels more like I'm smashing through rather than cutting. Also the sides of the mortise are not as smooth as I expect. Is this normal?
What about Delta bits? Pro or Heavy duty? Any advice would be much appiciated. I spent many moons making the quadraliner bed posts and want to start on the mortices but I don't want to muck up hours and hours I've put in thus far.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

What sized chisel and bit. 1/2" and larger do require extra effort. By "tuned" you mean that you sharpened the chisel with a cone shaped stone and "POLISHED the out side of the chisel to a mirror smooth finish? It could be a crap bit and chisel if the bit is not clearing out the debris.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
BD wrote: > I recently posted a topic on setting up a mortiser and the bit. As for > as I can tell everything is tuned as best an I can get it. The problem > is that I just can't believe the performance I'm getting is normal. > > I have to use damn gorilla strength to get through QS white oak and on > some test cuts it started smoking heavily on the first cut.
<snip>
Recently had to make some 3/8" M/T joints in white oak.
Based on your previous tale of woe, decided to use a drill press and a carbide forstner bit.
Clamped a couple of pieces of scrap to hold the part in position and had at it.
Took about an hour to make 8 mortices.
Used a 4 flute end mill in the drill press to clean up the scallops.
Piece of cake.
YMMV
Lew
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
BD (in snipped-for-privacy@p79g2000cwp.googlegroups.com) said:
| I have to use damn gorilla strength to get through QS white oak and | on some test cuts it started smoking heavily on the first cut. It | seems as though the bit is just crap but its right out of the box | and I tuned it up as per a FWW article I just read.
Jack Novak (sp?) posted an absolutely first class article here a while back on how to set up a hollow chisel mortiser. Spacing is the key.
Smoke is not a good thing.
It sounds as if you need to get one of the conical stone sets to sharpen the chisel. It does take a bit of effort; but not the hurclean effort you describe. That chisel needs to be razor sharp.
If you burned the bit (look for discolored metal) you may need to replace it. :-(
-- Morris Dovey DeSoto Solar DeSoto, Iowa USA http://www.iedu.com/DeSoto
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
http://home.comcast.net/~charliebcz/MChiselBitSettingTrick.html
Morris Dovey wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks everyone. I'm buying a new chisel set tonight. I'm going with the woodcraft brand (Its all they have in stock for 1/2".) Surprisingly the finish on it is better than most of the others but I will still give it a tune up.
Thanks also for the spacing tips.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
BD wrote:

the very wood that caused you problems with your current bit.
Maybe the previous owners of your current bit overheated it so its ability to hold an edge/perform has been compromised?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Everyone mentioned sharpening the chisel. That is a very important step. Bits can be crap from the factory also. A small file will touch them up and greatly improve cutting and eliminate the smoke.
Sharpen the flat cutting edge and also the inside of the vertical portion. Only takes a few strokes to make a big difference.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com (in snipped-for-privacy@m73g2000cwd.googlegroups.com) said:
| Morris Dovey wrote: || || Jack Novak (sp?) posted an absolutely first class article here a || while back on how to set up a hollow chisel mortiser. Spacing is || the key. | | http://home.comcast.net/~charliebcz/MChiselBitSettingTrick.html
That's the very article I remembered. Good info! Thanks.
-- Morris Dovey DeSoto Solar DeSoto, Iowa USA http://www.iedu.com/DeSoto
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Morris Dovey wrote:

The spelling's right!
Charlie B has the method listed on his web site at:
http://home.comcast.net/~charliebcz/MChiselBitSettingTrick.html
--
Jack Novak
Buffalo, NY - USA
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
no(SPAM)vasys wrote:

To give credit where it's actually due - The Forty Cent Method isn't my idea, but rather, as noted in the page on the method, was described to me by the Fisch (or is it Fische?) rep at a wood working show. I just illustrated the method. And someone here provided the Euro equivalent for the metric folks.
At the time I bought my General International 75-075M tilting head, XY table unit, good hold down/in device and LONG handle. I "needed" it. If you look at the first illustration on this page, and realize that just about everything is held together with mortise and tenons, some are BIG tenons. you understand why I "needed" a mortising machine.
http://home.comcast.net/~charliebcz/MT/CBbench6.html
The glue up was a "challenge" - http://home.comcast.net/~charliebcz/MT/CBbench18.html
And if you have a lot of M&T joints that have to be glued up at one time - here's a tip that may save you some grief..
http://home.comcast.net/~charliebcz/MT/CBbench19.html
Back to mortising machines - there are a multitude of less than obvious sources of problems.
1. If your stock isn't prepared properly - flat faces, square edges, parallel faces, straight edges etc. any one of these being off will likely bite you in the ass somewhere along the way. If the face you're mortising isn't parallel to the opposite face the bit - and chisel - can wander a little.
2. If the part isn't held down on the table AND tight against the fence the chisel may bind - and raise hell. You should NOT have to deadblow the part off the chisel.
3. If the back of the chisel isn't set parallel to the fence you''ll get a skewed up mortise. This is where an XY table comes in handy - move the fence up to the back face of the chisel, get the fence and chisel against each other, lock the chisel down and off you go! The XY table also makes aligning the bit to a layout line SO MUCH EASIER.
4. If you "nibble your way" such that the some or most of the bit is hanging out in the air in the space previously created, it will wander all over hell - and may burn itself AND the chisel while making a BAD mortise. Ideally you want the first pass at the cuts to have the bit surrounded by wood as the plunge is made. The little bits left after the first pass should be pretty thin - not beefy enough to cause the bit to wander - and easy to cut with just the chisel
5. Unless you have a really small bench top unit, with a small motor, faster is better. Do a series of cuts and really pull that lever hard and fairly fast. That'll keep the bit cutting rather than abrading the wood. Big curlies/chips don't get caught between the bit and the inside of the chisel. If what's coming out of the opening in the side of the chisel looks like hairs you're not pulling down hard enough. Of course, if your motor bogs down significantly when you do . . .
6. Like bench chisels made from crappy steel, crappy chisels and bits are worse than none at all. Rather than cutting mortises, you'll either spend a lot of time cussing and swearing - or sharpening. I like the Fisch chisels and bits - and you can pick up a set of their lower end, but still pricey, sets for a good "show price" at woodworking shows. NOTE: there doesn't seem to be a "standard" when it comes to mortising chisels and bits - where they connect to the mortiser. Know your mortising machines "sleeve" (or "sleeves") inside diameter AND outside diameter. It's a real let down if you get home with your new set and find they don't fit your mortising machine. Take the "sleeve(s)" with you when you go to make your purchase.
Why not simplify your life and just go with routed mortises and loose tenons? If you already have a plunge router and maybe an upcut spiral bit or two the TREND Mortise & Tenon Jig, without their bits and just their 2 1/8" guide will do the job nicely - with a bit less grief, cussing and swearing etc.
http://home.comcast.net/~charliebcz/TrendMTjig/TrendMTjig1.html
I just did 24 loose tenon M&T joints for some bonsai stands I'm making - that's 48 mortises to cut - in three different lengths. Quick and easier - and NO SMOKE, NO SCREACHING no sore arm.
Consider this alternative.
charlie b
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Did you have the bit turning at HIGH enough speed? Maybe you're just hogging out material too slowly. (My very first mortise with my drill press attachment was tough going until I sped it up. YMMV)
- Owen -
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I have said it before and I will repeat myself....
(1) Forget the mortising machine. (2) Buy a decent plunge router and some spiral bits. (3) Build one or more jigs to use for mortising. (4) Stop fighting the wood with difficult tools.
I have a mortising machine with sharp bits and I still think it's a piece of junk compared to my routers.
BD wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.