Purchased a Delta 14-651 benchtop mortiser and am wondering if there are some tips for getting one of these to work well. The problems are as follows–the plunging action of the mortiser is stiff, and I’ve already loosened the hex bolt that is supposed to make the action smoother. For example, the action is stiff enough that if I lower the head of the machine and then let go of the handle, the thing just sits there and won’t rise at all until I manually raise it. It will stick at any position I happen to leave it at.
Secondly, the bits are jamming very easily with chips and are very difficult to plunge into the wood. I began by leaving the 3/16″ clearance between the tip of the bit and the tip of the chisel, as specified in the manual, and that didn’t work, so I left a bigger clearance, and that hasn’t made any difference.
The woods I’ve used the machine on so far are fir and red oak; just some test cuts.
Any advice would be much appreciated. I’ve never had this much trouble getting a piece of machinery to work before; the results I’m getting feel like I must be doing everything wrong somehow, but that seems a little odd. Anyone have similar problems? Are there any tricks to tuning these machines? What sort of rate do you use when boring into the wood? So far it’s taking a lot more pressure than I would have expected–not at all as effortless as the drill press. Thanks for any suggestions.
LeoL
Replies
Try sharpening the chisel. Something like this: http://www.rockler.com/findit.cfm?page=11153 Lee Valley has something similar.
It does take some pressure. That's why the handle is so long. While the drill bit is clearing out the center, the 4 corners get simultaneously chiseled out by the square portion of the bit assembly, so it takes a bit of force. A benchtop machine must be bolted or clamped to the bench, or it won't work.
Edited 9/11/2005 3:26 am ET by BarryO
BarryO. Thanks for the link. I hadn't really considered honing them, I guess, because they're brand new and very sharp already, but it makes sense, as that's pretty much what you do with other blades and chisels that are new. I will do that.
The mortiser sits in a pocket I made for it along a countertop, just down the way from my miter saw, so the work can sit flush on the counter. Bolting it down in the pocket sounds like the next thing to do.
Also, I think there is some racking that's occurring because the work needs secured more firmly; the hold down isn't very effective and offers really almost no resistance against lateral movement of the piece during boring. I'm going to go down here in a minute and try some other clamps and such. Hand pressure against the fence maybe isn't enough.
LeoL,
Taking the time to sharpen the chisels that were provided with the mortiser will make a huge improvement, but be certain to sharpen and hone each side equally... Overzealous sharpening can easily transform your square chisel into a rectangular chisel, or worse!
I find that the Delta chisels that come with the mortiser are servicable, but once you find which sizes you rely on the most, plan to replace these with a better set. Whiteside and CMT bits have performed very well for me, and I am sure there are other good replacement chisels available. I have seen quality sets offered by Garrett Wade, Highland Hardware, Veritas and Woodcraft.
When installing your chisels, also be certain that the chip ejection slots run along the length of the mortise. Otherwise, chips can easily jam between the rotating bit and the "wall" of the mortise you are trying to cut.
I keep a can of spray dry lubricant handy, and give the bit and the chisel an extra shot or two especially when working with hardwoods.
I agree that the hold-down mechanism is lacking, but see FWW #175 (Feb. 2005) for a great solution. I mounted a 6" cross-slide vise to a plywood carriage mounted with four quick-release cams to two t-tracks dadoed into the benchtop. This arrangement allows me to remove the vise when I need additional length (for mortising the ends of bed frame posts, for example).
With sharp chisels, a well-lubed and adjusted rack and pinion, and a good hold-down, you should be able to drill out beautiful mortises in no time.
Since I tuned and tinkered a bit, I've cut more mortises with my Delta than I care to count.
Hope these tips help...
STEELHEAD
"The first rule of intelligent tinkering is to save all the pieces."
- Aldo Leopold
Thanks a lot for the tips. I don't know why, but upgrading the chisels/bits that came with the machine never occurred to me. Right now I'll definitely be using the 1/4" bit all of the time for cabinet doors. Where did you find the CMT and Whiteside mortising chisels? I just saw what Garrett Wade has to offer but would be interested to see the CMT and Whiteside too. Don't find them anywhere.
Also, I will definitely look up that article in FWW that you referenced. Your setup sounds very interesting. I'm all about tinkering too. Thanks again. Your advice definitely helps.
I have a Jet.. Same thing... DO NOT loosen the bolt.. Keeps the shaft in-line.. It is manual work... and will loosen up as you use it.. Make sure the shaft is clean and lightly oiled.. I clean mine every time I use it.. But, then again I do that to ALL my tools..
I mostly use my routers but sometimes I use it.. Has it's place...
I made ALOT of Horse Jumping Standards.. Oak and Cedar.. I find the Jet works better than all the router set-ups I'd have to do...
Leo,
Things are not so bad as you think. I have never used a morticing machine that was able to lift itself back up, so don't wory about that. I am not sure which bolt you loosened, but if it was the gib screws that tighten the dovetail ways, you should tighten them up again. The Delta unit I have came with good chisels that worked a lot batter after I honed the inside and laped the sides. Mortising machines turn pretty slow, so they cut diferently than a Drill Press unit that was probably turning faster. Giving more clearance than recomended usually dosent help. The chips still have to travel up the chisel and out the hole.
Good luck,
Mike
I have the same machine:
1. Get the best chisels
2. Clamp the workpiece firmly to the fence. I know it's tedious when you're chain drilling, but it's necessary
3. Plunge in stages, each time letting the chips clear completely. You can judge this by the sound.
4. The head isn't really supposed to go back up by itself.
LeoL,
I bought the first benchtop mortiser that Delta released - several years ago. It came with a set of 4 inexpensive (cheap) bits/chisels that were somewhat rough-finished, inside and out. I immediately bought a set of upgraded Delta bits/chisels that had MUCH better fit and finish. All the initial problems I had with the cheap bits went away when I upgraded.
I don't know if Delta still sells (or supplies) two levels of bits but I belive most, if not all, of your issues will be minimized with better bits - or by improving the fit and finish of the supplied bits.
Good luck,
Richard Baker
Thanks everyone for taking the time to reply. I really appreciate it. You gave me some really good suggestions that sound like they're going to solve my problems.
LeoL,
Most Woodcraft stores have the option to special order CMT or Whiteside bits and chisel sets that they don't stock. I have a local Hogan Hardwoods Store that has always been able to get whatever Whiteside products I want.
See the following link for Whiteside's website:
http://www.whitesiderouterbits.com/CompanyHistory.asp
I have always found Whiteside's router bits and other parts to be of the highest quality (and no, I don't work for them...). I've been trying to wear out a 1/2" Spiral upcut bit for a couple of years now, but haven't been able to manage...
I hope this helps, and let us know how you are making out once you get your mortiser up to speed.
STEELHEAD
"The first rule of intelligent tinkering is to save all the pieces." - Aldo Leopold
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