I enjoy the look of a through mortise, and try to use them whenever possible. I just bought the little Delta mortiser, hoping that my mortises would be a bit more exact- When I chop them via chisels, I can’t seem to have a good fit, so I bought the machine.
My problem is that my bit is squared, it’s sharp, and my tenon is very straight and square. However, both sides of the mortise are a bit ragged, especially where it exits. So, when I fit it up, it doesn’t look as good as it could. Am I missing something? Obviously some practice would help, but does anyone have suggestions?
Replies
Cut half way through and flip the piece end for end, and cut back to the middle. You'll have to square your lines around to the far edge with a square and pencil/knife. This is a completely normal routine. Slainte.
Sgian always gives good advise. I would check to make sure your chisels are very sharp with no burrs, if the outsides are polished to a mirror smooth finish the work is easier and the entry hole is clean and crisp. The exit hole is a problem, make sure your work is backed up with a fresh scrap block of a wood harder than the wood you are morticing. A back up block of pine or alder will crush leaving a ragged exit hole.
Stephen
Backing up & switching sides both work well and a sharp polished tool is a must. Another way to get a smooth exit side is to cut your stock oversize by 1/8th inch or so oversize and then plain to exact size after chopping mortise....wastes a little wood but works well also.
George:
I agree with Sgian and Stephen also. I have never thought of yours. Thanks very much. That adds another approach to my bag of tricks!!
Have a great holiday week-end..
sarge..jt
Anyone ever have tear out problems doing this?
Don:
I'm not sure you meant to send post to me? I have used the method Sgian and Stephen used with no tear-out. I have never heard of George's method or thought of it. It seems it would be a sound approach with the draw-back he mentioned. A little extra work and some waste of wood. I can't imagine there would be any problem in George's method as any tear-out on exit would simply be planed away in execution of his original plan.
If you meant to direct toward Sgian or Stephen's method, you might re-direct post. I know their method works as I use Stephen' approach. I have used Sgian's also but I find I have to be very cautious to make sure when you turn work-piece over you have it aligned properly or the two holes won't meet exactly. Not that I've ever had that happen.he..grin>>
sarge..jt
Sarge,
It wasn't directed to you. You just happen to be prior to me, so you got the addy. I just had thoughts of a jointer ripping the edge of the mortise.
As for the other sentiment. I don't see how it could happen to you. I've never even heard of misaligning something. Must be one of foriegn practices or something????? Nope, never heard of it.
8^|
Don
Don:
Nope. Me either. I read that deal about mis-aligning in some Afgan Wood Mag.
You know, as we get older; that fish we caught keeps getting bigger and bigger doesn't it.. Well, gotta run. I got to go skin that killer-whale I caught in the creek out back this after-noon! giggle..
sarge..jt
I would think that if you cut from the visible side through & back up, any normal tear out would be covered by the shoulders. Am I missing soumething?
Dave
Dave:
I agree with you. I use Stephen's method as my preference, but all three methods would work. I'm not sure why Purswell is getting a ragged entry hole.? The exit is the norm as you know for the crucial part. I wonder if Stephen may be on to something about burrs on the chisel. I have honed tools that looked good by eye-sight. I put them under a little magnifying glass and opps, need a little more work with that high grit water-stone or what-ever sharpening method you use.
I suppose you could use a piece of hard scrap for entry, but it interferes with initial alignment. Maybe, if you align first and then put the backer over the entry? I have never had a problem with entry. I'm headed for the shop to try this. Just curious. Ha.. Most of what I learn new is because I'm just curious..grin>
sarge..jt
Dave:
Dis-regard last post to you. Got all the way to the shop to try and suddenly the light bulbs came on. YES, if you back up to eliminate tear-out on exit any tear-out on entry should be covered by the shoulder. Dah! I'm obviously one cup of coffee short and possibly one toxic fume from wake-up.
Good point! Curious to hear answer, unless Purswell just happened to notice this and thought it unusual. Seems lot of unusual things happen in this forum. IMO only, of course....
sarge..jt
Thanks for all the ideas- I didn't sharpen the chisels much- I don't really know how. I can polish the outsides of them, but the inside rounded part...?
The tenon shoulders do cover, but I still have clean-up on the entrance hole. After I clean things up with a hand chisel, my squares are okay, but I was trying to get to where through mortises could be exact- no gap anywhere. I guess practice and time is what it takes.
Thanks
PURSWELL:
You might consider "The Complete Guide To Sharpening" by Leonard Lee, the founder of Lee Valley and Veritas. I learned much from his book that just doesn't get passed on sharpening all tools. About $23 and worth every penny IMO. I don't know if you have sources literature, so if nothing else here's a website here in Atlanta that is mecca for us down-south folks. http://www.highlandhardware.com They'll send you a catalog free too.
Good Luck..
sarge..jt
It comes to mind that the rotating bit cuts a little larger opening than the chisel will clean up. This is seldom a problem since the sides of the mortise is usually not seen.I think that if you cut the slot with your hollow chisel machine in the usual manner ,going almost thru the detail part. Transfer the lines as has been suggested,then cut the show side of the mortise with a chisel and mallet,you would get a smoother and better looking finished joint. FWIW¬¬¬¬¬¬¬¬¬¬¬¬PAT¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬
Pat:
I think you just added an excellent finishing touch!
sarge..jt
Wrap a piece of 600 grit sandpaper around a small wooden dowel to dress up the inside of the hollow mortice chisel. Then remove any burr from the outside edge.
Stephen
Does anyone know if the chisel bit sets that come with the Delta drill press kit are the same that come with the mortiser? The kit is $70 and the bitchisel sets go for $39 to $45 each. It would be less expensive to buy the whole kit and get more for replacements andor spares. I find it annoying to stop in the middle of something even if to sharpen a bit. Of course this is under the assumption the bitchisel sets are the same.
Don
Edited 9/2/2002 10:39:33 PM ET by Don C.
I have this question as well. From what I've read, there are Asian, and then European, sets, with the Eoropean sets more expensive and mcuh better. Perhaps it is old pricing we are seeing? I have the set, and used it a good bit, carefully, without replacement or sharpening. Wonder how the good ones would be. Does anyone know if the price difference is worth it?
s4s:
I'll attempt to give you an opinion based on what little I know of the chisels. The Left Coast crowd kept me up late last nite and I'm in desparate need of coffee. I don't know what kind of chisels are in the Delta sets, but I can tell you that most all brands come with Taiwanese made chisels. If the quality control of the company having them made is good, that in itself is not a problem. IMO. I think the problem lies in the grade of metal being used. I am an absolute believer and practicer of keeping tools as sharp as possible. In order to get excellent edges that will stay that way requires work. It also requires an excellent grade of properly tempered, hardened steel. You can put a good edge on cheaper steel, but watch with a magnifying glass what happens after you have used it. That is especially true with the harder woods. You see the edges gap and get ragged easily. The cheaper steel is brittle. You get what you pay for (most of the time)..!
I suggest you purchase Leonard Lee's (president of Lee Valley and Veritas) book Complete Guide to Sharpening. It's worth the $23. IMO..It's unlocked a lot of what used to be mysteries to me in this area.
The cheaper chisels work OK, don't get me wrong. A higher grade set with it's better grade steel and more stringent machining just Get and Keep better edges much longer.IMO only. Correct me if you find different results. Constructive critique is how I learn..
Have a good day..
sarge..jt
Sarge,
My question was are the chiselbit sets that come with Delta's hollow chisel mortiser the same as the ones that come with their drill press mostising set???? If so, a complete set of bitchisels can be had for about a third the price of the chiselbit sets bought individually. The chiselbit sets that came with my hollow chisel mortiser, Delta, are fine IMO. I don't know anything about what steel they are made from, or where they are made.
Don
Don:
I was just giving my thoughts on what sks asked about the difference between European and Chinese. As I stated, I didn't know what Delta come with. I just called tech support at Highland Hardware who are Delta dealers and here's what they had to say:
The bits that come with the 14-650 mortiser are Chinese, even though they said they are pretty good. The individual ones you probaly saw are the Delta model # 17-908, 17-909, 10 and 11. They are way up in price as Delta has them made in Austria. Different quality, different price. These may be a good quality set. I'm curious also as I haven't had time to experiment with different brands yet. See last post to sks as to this would be a great thread. I noticed Biscardi got interested too. I've got to get to work, but hope to come home this evening and see some reponses here or another thread! Ha..
Have a good and productive day..
sarge..jt
Sarge,
I would like to get another 1/2". I think I'll order one from Amazon and see how it compares to the Chinese one that came with the mortiser.
Don
Don:
Good idea! Let me know down the road as this is an interesting subject. Biscardi has a good point also, as I like to shop and get the best quality for the money. I hope others respond that have had different brands awhile. I don't see much on the subject..
I' out the door, tried to squeeze in a last second response, Got 13 mi. to to in 30 minutes. grin>> have to talk about old classic cars for the next 6 hours..How dreary..ha..
sarge..jt
Which chisels, from whom, do you recommend?
Alan T.
This brings up a good point. Why don't tool companies tell you the type of steel the tools are made of? This would be helpfull if you ever had to re heat treat them. Also Rockwell hardness # / points of carbon etc . . . would alow one to comparison shop.
Frank
s4s:
I would rather not reccomend as I have had my mortiser for a short time. I have used mortisers often at the local tech school (another thread), but my mortise slots have been done by router or hand previously. I bough the Fisch from Austrailia. I have been told that Clecko (spelling) from England are good also. I have used the Taiwanese with success at the tech school, I was trying to explain what I IMO thought the difference would be.
This would be a good thread, if you want to get it started. I would like to hear from those that have used both the European (etc.) and the Taiwanese and get some opinions of what they think!
Got to get ready work..
sarge..jt
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