Multi-Router (Slot Mortiser) Progress

[Guy Kowalski]

Not too much more to go. Just have to finish the X stops and Y stops and the X movement arm. I am pretty happy with the progress. I am real happy because about 5 weeks ago I never touched a Bridgeport Milling Machine before. I learned the milling machine (not difficult but you have to think in thousanths instead of 32nds and 16ths and 8ths and the digital readout makes it much easier because you can zero X and Y on a corner and reference all your milling to that zero reference. Talk about precision. Well, here are some photos of the Multi-Router in progress

http://woodworkersweb.com/posting_pix/side.jpg

Side View

http://woodworkersweb.com/posting_pix/front.jpg

Front View

http://woodworkersweb.com/posting_pix/mill.jpg

The Bridgeport Milling Machine I used

http://woodworkersweb.com/posting_pix/me.jpg

My buddy Larry (Machine Shop Owner) who just wanted to get his picture on the Internet


A complete set of pictures of this machine evolving can be seen here (http://www.woodworkersweb.com/modules.php?set_albumName=album23&op=modload&name=gallery&file=index&include=view_album.php).

:)

[Don Henthorn Smithville, TX]

Impressive project. Have you used it yet for a project?

[Guy Kowalski]

Don,

Not yet. Just one more weekend to finish it. I need to finish the X axis movement arm. I think I will build a craftsmen piece with alot of mortises to test it. It was alot of fun to build and also fun learning how to use a milling machine.

[Dan Barber]

It looks like you are making some fine progress.

Metal working in it's own way is just as rewarding as woodworking - be careful - that is a very expensive hobby!

Just one comment, it looks like you are mounting the router in the box arrangement mounted to your vertical Thomson Rods. The amount of cantilever you have away from the vertical axis is going to apply a large moment of force to those vertical rods. From the photos the rods look to be 3/4" (or .750 to your new found form of measurement :) ). Something on the order of 1-1/4 or 1-1/2 would be better in this situation.

When the router is being used to cut mortises, a large amount of force is transfered back to the router. I guess what I am trying to say is I think you are headed for trouble with your design. As far along as you are, I'd recommend finishing it enough to try it out and see if my suspicions are correct. I think you will find your cuts are going to be inconsistent because of the ability of the router (at the bit end) to flex up and down.

If I'm correct, you could change your design to mount the Thomson Bearings directly to the plate the router is mounted to. This would apply the forces generated by the router to the rods with out the multiplication of forces the cantilever design imparts. See the included photo for an illustration of my point.

http://www.woodisourart.com/mortiseflex/images/DSC00075.jpg

Also the further apart the bearing blocks are, the better the situation will be. I'd try to get the bearings separated by at least 1.5 times the diameter of the router body.

I know this would mean relocating your vertical adjustment screw to one side or the other - which probably seems illogical. In actuality the placement of the screw to one side is probably not an issue with the geometry and forces involved during adjustment.

I may be all wet here - and I hope I am! As you may know, I built one of these machines and have some experience using it that leads to my concerns. If I missed something in my observation, please accept my apology. Please keep us posted on the outcome.

Cheers,

Dan

BTW, I want a shop like your buddy has!

[Guy Kowalski]

Dan,

No need to apologize. I appreciate your feedback. I will try it and if it does not work I will take your suggestion and redesign the Z axis assembly. I am a degreed electrical engineer who unfortunately never took a statics and dynamics course. I was originally going to duplicate your design in wood. I mentioned my intention to build one of these to my friend Larry who happened to own a machine shop. He said, "why not make it out of aluminum" and volunteered his shop on the weekends and taught me how to use the Bridgeport milling machine. I have had alot of fun and I am already trying to figure out how I can fit a used Bridgeport in my gararge shop. I will let you know how it works. I also hope you are wrong.;) :D

[Keith Outten]

Guy,

Nice work!
You seem to have a knack for metal work and beware it can be addictive. When I was in high school I used to hang out in a local machine shop and got the bug. I have a mill/drill and metal lathe in my shop, I use them to build jigs, fixtures and make parts for old machines.

The cantilever aspect of your design does look like it might pose a problem, time will tell. Any flex in the .750" dia rods will translate into chatter, a real problem in the machining world. I expect that your friend Larry has blessed your design and he would know better then most if your design had a major flaw.

When your finished with the project I hope you will write an article and let us post it here at SawMill Creek.

Thanks for the pictures.

[David Blangger]

No! No! No! you need to start all over. Just ship it to me :D when you finish this one and I will test it for a lifetime to be sure:D


Looks great. You are becoming a man of many talents regardless how you measure it.

David