Building a horizontal slot mortiser?
A couple of years back I was in a woodshop (on an open studios tour) and saw a home built slot motiser. As I remember, it had a motor connected by belt to a rod-like fixture (mandrel?) spinning in bearings, with a chuck on the business end. An end mill like bit went into the chuck. This was all on the top of a bench, with the bit facing out. Then there was a sliding table sticking out from the bench, about 4″ below the bit, with two sets of two linear bearing slides, mounted 90 degress apart with a board in between them, and a board on top. End result was that the table could slide in and out, and side to side. The guy would pile wood on the table until the table height worked for whatever mortise he was cutting, put the piece on the table, slide it in, over and out and Voila, a mortise. I didn’t see it in operation, but I expressed interest and he gave me a quick verbal description in between people milling about asking questions about his work.
So I’m interested in building something similar and spent some time browsing the MSC catalog. This is pretty unknown territory for me, so I don’t know what the set of gear I need is called. The part that turns in the bearings, can attach a chuck to the front and a pulley to the rear. It obviously has to be able to withstand the thrust of the work pushing into the bit. In addition, it seems that a lever to move the table each way would make it all way easier.
Anyone have any advice or insight in to how to go about this?
Thanks,
Jim
Replies
I think one of the TV woodworkers has one that is similar. Richard Marks? Didn't Woodcraft supply carry one a few years back for small shops, multi-rout? You can do some cool tricks with a plunge router in a horizontal router table. That is, a router table with the router mounted on the fence so to speak not under the table. A sidewinder. The Shopmate tool has a horizontal mortice attachment as do many of the euro combo machines. Industrial level horizontal borers are also available but not inexpensive.
FWW # 141 has the simplest slot mortiser you can build and it does work. Haven't built it myself but saw one similar a few years before the article came out and was pretty impressed. The next step up is to buy the mortising unit off a combination machine from Laguna. About $500.
You can set it up with a router or better yet with a regular motor, pillow blocks and a shaft. It comes with a mortising chuck. Been using slot mortisers for 20 years and made a few as well. One of the best secret tools of woodworking.
Popular Woodworking carried a plan for one several years ago, and the plan is widely available. It does not use linear bearings, which would be better. There is a fellow out of Rochester NY, on ebay, who sells linear bearing by Thomson, which I think are good ones, and they are quite a bit less expensive than going to an industrial supply house. I have not designed or built one, but would love to see a print for a good one using the linear bearings. I think that for a pair of 1/2" bearings, with the rods, it is about 60 - 80 dollars. He has them up to at least 2" dia.
There's an article in FWW issue #141, "Shop-Built Horizontal Mortiser," by John Matousek (pp. 67-69). His version uses a router and drawer slides to accomplish the same thing.
http://woodcentral.com/shots/shot390.shtml
Bruce
Jim, The device is a 1/2"steel bolt with it's head cut off and with a threaded end 1/2-20 fine thread.
It is supported by two 'pillow blocks' and the opposite end will take a v pulley with 1/2" bore.
The chuck is 1/2" capacity with 1/2x20 internal thread.
The whole arrangement is mounted and blocked up with four bolts through the work bench The pillow blocks' ballbearings (2)are 1/2" id.
They'll need 4 1/2" collars to keep the shaft in position
The motor can be mounted either along side and parallel to the shaft's pulley, or mounted beneath the table and a slot provided for the vee belt. The sliding and indexing (X Y) fence can be made with sliding dovetails or sections of table leaf slides.
( I used sheaves and rails used for sliding cabinet doors)
Motor must turn clockwise and I recommend 3450 rpm speed. Can use spiral router bits instead of end mills.
Using blocks to allign the support is simple, but I'd make an adjustable 'lift' with two threaded bolts to raise and lower the contraption .Stein.
Or use the threaded column and nut from an office chair.and a hand wheel Like a wine press?
Edited 11/15/2003 6:29:58 PM ET by steinmetz
I seen a home made one in American Woodworker -96 97 98 ? not sure which year or issue.
He had used a router on its side and a drill press vise -the vise was the kind that would adjust from side to side and in & out with the crank handles- it looked to be a good working mortiser .
The Multi Router is very similar to the way the home made mortiser worked.
Ron
Who Ever Has The Biggest Pile Of Tools When You Die Wins
I bought the one I use for cabinet, entry and passage doors from Laguna Tools for about $700 with stand. It took some modification and strengthening, mainly to make sure everything stayed dead square, and it's worked perfectly for the last 10 years.
Rob,
What did you do to strengthen the Laguna version of the multirouter. I bought one with my planer/jointer along with a stand but don't use it very often because it gives me a sloppy joint.
Thanks,
Phil
Phil, I think I have pictures somewhere. Send me your snail mail address and I'll send them, but you have to send them back. I'm in Los Angeles and if you're close, come look in person.
There are a # of things that have to be done. First, to stop the entire router/sliding table assembly from sagging, I propped it up with a piece of 3/4" x 4" aluminum, bolted to angle iron and channel iron brackets I'd welded to the base and the bottom of the carriage assembly. Second, that piece of 8" x 8" x1/4" black angle iron which holds the router is too flexible. I triangulated each side, corner to corner with 1/2" steel rods, threaded 1/2-20 RH and 1/2-20 LH on each end, running in the appropriate nuts welded to the corners of the angle iron. They work like turnbuckles, allowing me to fine tune the angle between the router face and the table to get and keep an absolute 90*. Of course, each rod has a locknut. Third, where the bottom of the big angle iron sits on the square base wants to rotate under hard use. I drilled and tapped SAE fine 3/8 for a couple of pinch bolts. Finally, the work holding system sucks. I threw out the original cam/lock system and drilled and tapped 3/8-16 holes in the table to mount and dismount Jorgensen surface clamps. The handles from the discarded system now lock and unlock the rods that limit travel.
I can now do 7/4 entrance doors all day and the last mortise is in the same place as the first one to the best I can measure.
Rob,
Thanks for the details, I have a good understanding of what you did. I already modified the hold down system and added an L=shaped bracket bolted to the sliding table to hold smaller pieces.
Phil
I bought the Feb '03 edition of Woodworkers Journal for the article on "Build the Ultimate Router Table". The table has an accessory arm that the routher attaches to horizontally. The arm has a microadjustment feature, and looks to me like it would work very well as a horizontal mortise attachment with the addition of a spiral bit and a few stop blocks.
It seems that this approach would be a lot simpler, cheaper, and easier than trying to build a dedicated machine.
I built something very similar to what you are describing. I had an old electrical motor that already had a speed of 2750 rpm, so it was quite appropiate for the problem. A machinist attached a chuck directly to the motor shaft, the ordinary kind with a key, to form the core of the machine. I bougth eigth friction bearings and four mecanized (polished) rods and end supports of 16mm. I used eigth instead of four to obtain a wider support for the torsion forces.The rest is precisely as you describe and everything made of wood. I have been using the machine for the last year, it is very precise and I am very happy with it.
I am a weekend woodworker so the usage that it gets is not very demmanding. I was worried about the the motor bearings not to be able to whistand the horizontal forces when mortising. The machinist that made the attachement of the chuck checked the bearings and thougth that there was no problem.
The friction bearings ( I don't know if that is the rigth name in english) are a lot cheaper than regular linear bearings with balls inside, and work well enough for tis case. They also take up less room. I bought them in Spain, where I live, from a german company
Justo
In FW #98 on page 48 there is an article by Ross Day That shows how to build exactly what you refer to. It's on my list of future projects. Art
Coincidences ...
Name issues aside, see my post yesterday re a shop-made vertical mortiser, in "general discussion". You may not want to do it the way I did, but my contraption works well, and I find the vertical nature makes it easier to view. If you want more particulars than what is in the post, let me know and I'll get them to you. I've seen the FWW article mentioned in some of the responses, and it did look like it would work. Good luck with what ever you decide to make.
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