# base plate for mortising? How make it? help



## Bogydave (Nov 14, 2008)

Got 1/4" clear acrylic. 
Using drawing I got from bobj3.
Found out Bosch baseplate screw are metric. 4mm (Back to Lowes again)
Got 2 brass 1/4" bolts & will cut heads off. (will order the mortise bearings but on christmas list)
How big sq is the new base plate? (i was going to go 7")
How to get it centered on the plunge router base so corner to corner center is bit center and base plate holes line up?
How to cut center hole in base plate? How big?

http://www.routerforums.com/attachments/jigs-fixtures/4020d1167540456-mortise-tenon-jig-plunge-router-center.gif


----------



## Bogydave (Nov 14, 2008)

I think so, if I put the router in the plunge base with a "V" bit & line the cent on the point of the "V" bit, mark the holes.
Only thing is if the holes are off any at all then what?
Are the new base plate mounting holes to be a little larger than the 4m screws so it can move, then snug it down?


----------



## bobj3 (Jan 17, 2006)

Hi Bogydave

This is the way I make them 

I do like to make them 8" x 8" square.
Some of the plastic comes with paper on it if not put some masking tape on it.
Next draw a FINE line from corner to corner ,then draw a line around the corners about 1" from the out side edges.
When the line goes across the X line, draw a small cir.around it, then chuck up a 1/16" drill bit in the drill press ,drill the center hole mark and then the out side holes on all 4 corners,,,

Once you have that done chuck up a 5/16" drill bit (8mm) and drill out the holes on the corners, then chuck up a counter sink bit and just touch the holes you just drilled on both side of the new plate..to remove the small bur..

Then remove the base plate off the router, this will become the template to drill the mounting holes,,,,
This is the hard part because it needs to done just right and on dead center.

Make a disk that just fits the center hole in the plate,,,use a hole saw, for this job, because it will put in a 1/4" hole in the center of the disk, use some 1/4" MDF ,hardboard,plastic,etc...cut the disk out just a little bit bigger than the center hole in the base plate..now with care sand the disk so it can be press into the hole, sand a litle bit at a time, I made a jig to do this job but you can do it by hand but with care.

Once you have the disk made, take the new base plate to the drill press and pop in the 1/16" drill bit, then clamp the new base plate down to the drill press using the 1/16" hole to line up the clamp job,once you have the plate in place and then chuck up a 1/4" drill bit and drill out the center hole, drill out the center hole to 1/4",, then put the disk you made and the old base plate on top of the new plate.
Push the drill bit down into the two holes, this will line all the parts up then with some masking tape,tape the plate down all the way around the old plate...now unclamp the plate and with a 4mm drill drill out the mouinting holes, then put the 1/4" bit back in the chuck and reline the plate and clamp it down again,,,once you have it clamped down remove the old base plate and the disk you made...then chuck up a 1 3/8" bit or 1 3/4" bit..
This come down to what size of guides you want to use.
Once you have the bit in place drill down about 1/8" deep in to the plastic, then chuck up the 1 3/16" bit or the 1 1 /2" bit again this comes dow to what size you want to use,,, now dril out the center hole to the scrap block you have under the new base plate on the drill press.

Once you have the hole drilled out unclamp the base plae and remove the masking tape and the old base plate and chuck up a counter sink bit and counter sink the mounting holes so you mount the new base plate in place.

This is the long way but the safe way, once you do it a time or two you will find the short cuts, but for the 1st.time you need to do it this way to get the hang of it... .

For The bearing you can remove some off the router bits many router bits use the 5/16" (8mm) ID type.. ( 1/2",5/8",3/4" OD the norm)

hope this helps a bit

=====










Bogydave said:


> Got 1/4" clear acrylic.
> Using drawing I got from bobj3.
> Found out Bosch baseplate screw are metric. 4mm (Back to Lowes again)
> Got 2 brass 1/4" bolts & will cut heads off. (will order the mortise bearings but on christmas list)
> ...


----------



## Bogydave (Nov 14, 2008)

Wish I'd read this before I made (now my first one) this one. 7" X 7"
Haven't cut the center hole yet, wanted to see if I was on the right track to this point.








I was just going to make this base plate for mortises. I threaded the acrylic but may need to epoxy in the nut that holds the guide posts if it don't hold. 
(another rookie question) (too old to call em dumb ?s, but old enough to know to ask)
 bobj3"..then chuck up a 1 3/8" bit or 1 3/4" bit..
This come down to what size of guides you want to use."
Having never used guide bushings (yet), I believe the bosch I have has a unique bushing mounting clamp. Would I be better off buying a universal set & making the new bases fit them?
Here's what I got (all I got) router speaking.
View attachment 16762

Apologize for lack of router experience but hope to be a quick learner. 
Thanks for all the help. Has been very helpful. 
Will start a new base tomorrow with more knowledge.


----------



## RustyW (Dec 28, 2005)

Guides, or template guides, are something you will find many uses for if you hang around here. You have a couple that came with your new Bosch. They fit in the turret. Most common guides here in the US are threaded and fit in a stepped hole. There are two common sizes, the PC style, or the larger type from Oak Park or Lee Valley. They work similar to a bearing guided bit except there is an offset from edge of bit to edge of guide. To work properly they need to be perfectly centered around the bit. The benefit of using guides is that you can perform multiple steps on a project, with one template, by changing bits or guide sizes. 

It is very simple to center a hole in the base you made. Use the spiral bit in your pic (looks like a 3/8") to plunge right through it, either on some scrap or bridged over two pieces scrap. Than remove the base, clamp it to the drill press using bit that matches the hole size to center it. Than switch to a hole saw, or forstner bit that matches the hole size you want.


----------



## Bogydave (Nov 14, 2008)

Thanks
I've been reading allot on template guides. I'm gaining an understanding but, like normal, the learning comes when you do it. 
I may be trying to read & learn too much about using a router. I need to (now that I have some bits) just get after it. I'll just use a scrape piece tomorrow & try to cut some mortises before I do the oak table legs. It' just when I surf this site, I see & read so many different router uses, jigs, bits & various ways to do the same thing. I get wrapped up in the thought process & need to pick a way to try & get something done.
Building the router table will get me going in the right direction & gain experience with a router.


----------



## bobj3 (Jan 17, 2006)

Hi Bogydave

Well to be strait up with you don't need the guide hole in this type of plate and a 2" will work just fine..

I'm not a big fan of the steel guides, pork and beans can type of steel  , (like the ones in your snapshots) they are a real PITA to put in place ,it's so much easyer to put on a brass ring nut than to take the router down with a screw driver. the rule KISS comes into to play on this one. 

But you may want to make one more plate and on that one I recommend using the large brass guides.. it's not to big of a deal from the PC to the Oak Park type ,the big one will just let you use bigger bits plus it will let you see what you are doing at the router point...


======






Bogydave said:


> Wish I'd read this before I made (now my first one) this one. 7" X 7"
> Haven't cut the center hole yet, wanted to see if I was on the right track to this point.
> 
> I was just going to make this base plate for mortises. I threaded the acrylic but may need to epoxy in the nut that holds the guide posts if it don't hold.
> ...


----------



## Mike (Nov 22, 2004)

Dave, as you can see there is no one method that everyone likes. The important thing is for you to be comfortable with the methods you use. The Bosch quick release guide bushings are faster to use, just push into place and a quick flip of the lever. Many like BJ and I prefer the brass guide bushings. Since you do not want to be removing the guide pins from your mortising sub base plate just cut a 1-1/2" hole in the center and call it done. You can easily make another plate for using either PC or my preference the larger Oak Park style guide bushings. You will find the instructions for cutting the holes vary by user as well. I use hole saws and BJ uses Forstner bits. (I think) Use which ever feels right to you. There is no wrong way to do this. You will not be cutting mortises all the time and it is easy to change the sub base plates as needed. You can also make a nice circle cutting jig that attaches the same way.


----------



## curiousgeorge (Nov 6, 2006)

Dave,
Check this out...

http://eagleamerica.com/400-1292/p/400-1292/


----------



## Bogydave (Nov 14, 2008)

Here's what I came up with. Works OK but if I have to make many more mortises I'll make the jig bob talked about. 
Used my "V" bit to find center of baseplate then drilled 1-1/2" hole. 
Beginning to get the baseplate ideas & template guide bushing thing. Probably need to add to the christmas list.
Problems. Operator error. Having never used a plunge router I had trouble raising the router up out of the hole smoothly. I started getting the feel after a few routs. 1st couple weren't pretty. 1st one in the oak was ugly but they got better. (Pics on request only). I was probably too tense & was gripping the router too tight & not relaxed. (learned to hold it more like a golf club, firm but not too tight & relax) I put one pin off line about 5/8" to get within 1/4" of the edge of the wood. Making a few different locations for the pins would be useful but should be like bob said, an 8" baseplate. (next one)
Thanks for all the patience & help. Now I can move forward on the cabinet/table base. 
Rounding the tenons next.


----------



## curiousgeorge (Nov 6, 2006)

Looks like that should work great, Dave. The only problem might be the bolts marking the sides of the pieces as they slide along. Is this the case?


----------



## bobj3 (Jan 17, 2006)

Hi Bogydave

You did a great job and it looks like it will work just fine 

The offset pin is a good ideal, it shows me your using your head and the basic geometry to get the job done 

On your next plate do put in the hole to use the brass guides and I will show you a neat way to take the guess work out of putting in the slot off center .


=======


Bogydave said:


> Here's what I came up with. Works OK but if I have to make many more mortises I'll make the jig bob talked about.
> Used my "V" bit to find center of baseplate then drilled 1-1/2" hole.
> Beginning to get the baseplate ideas & template guide bushing thing. Probably need to add to the christmas list.
> Problems. Operator error. Having never used a plunge router I had trouble raising the router up out of the hole smoothly. I started getting the feel after a few routs. 1st couple weren't pretty. 1st one in the oak was ugly but they got better. (Pics on request only). I was probably too tense & was gripping the router too tight & not relaxed. (learned to hold it more like a golf club, firm but not too tight & relax) I put one pin off line about 5/8" to get within 1/4" of the edge of the wood. Making a few different locations for the pins would be useful but should be like bob said, an 8" baseplate. (next one)
> ...


----------



## Bogydave (Nov 14, 2008)

Didn't notice any marks on the wood from the pins (couple of weird marks on the inside of the mortise, looks like chainsaw was used.  LOL )

Before you you show me, see if what I think is close. Draw an arc using opposite pin as pivot for the arc. Center holes for the pin + 1" out on the arc would be 1/2' inch at the bit.??
Moving in on the center line (near the corners) would do the same, but harder (for me) to calculate the results on the bit.
Am I close to the "right way"?

Mike, isn't this a circle cutting baseplate already? Just pull one pin & circle will be the radius from center of pin to edge of bit (inside/outside). Not real versatile but will cut a circle. Saw a teardrop shaped "pomell" (sp) circle jig in a book with adjustable sliding center post gismo. Is there a simpler easier to make one? 

I also put a bushing over one pin (the wood was 1-1/2 X 1-5/8) to adjust when I did the other edge. Which goes back to using the bearings you wrote about, you can various OD bearings to move the bit around. If I used a standard 1/4" brass bolt & bought some various OD - of 1/4" bearings, I'd have the same results.
Is & was fun figuring out how to make it work for me using what I had in the shop. Only problem was operator error. Router operator needs more "chip making" time.
I know nobody on this site ever did something like this, means I'm the first, am glad it'll get covered & only you & I will know it's there


----------

