# First Box Joint with my new jig



## Chasing Summer (Apr 20, 2012)

Made a box joint jig from FineWoodworking video. Looks straight forward and relative simple to use.
Took a while to get the technique down but I finally got it adjusted just right.
I cut the pins on the sides of my drawers. 3/8" They fit snug over my spacer pin. Went well ... looked great.
I cut the pins on the front board .... HUH? they grew and don't match the side pieces. What happened?
The only thing I changed was from right to left on my jig.
HELP .... wood cost to much to waste


----------



## 27207 (Jan 25, 2012)

Pictures would help a lot here. you cutting these on the table saw with a dado set?


----------



## Chasing Summer (Apr 20, 2012)

*pictures*

I'll post pictures tomorrow as it's dark now. Yes, table saw with stack dado head. Spent a lot of time getting the blade thickness just right.


----------



## 27207 (Jan 25, 2012)

Check to make sure your stack didn't become loose. That's baffling


----------



## Chasing Summer (Apr 20, 2012)

I didn't run as a stack. I ran each board separately.


----------



## dbhost (Jan 28, 2008)

But you just said you used a stack dado... So did you or didn't you?


----------



## Chasing Summer (Apr 20, 2012)

I've seen video of multible boards being run through the jig. I thought that was what he was referring to as the "stack". NO, my blade stack is tight. Had it not my slot would have been loose on the guide pin.
Thank you for your comment. I just rechecked and YES, my stack is tight.


----------



## 27207 (Jan 25, 2012)

It's really hard to suggest without knowing all the details, but is your jig completely homemade? As in the guide runners and all? it could be just not quite perfect, so when you push the jig forward it kind of angles to the right, then pull it back and it angles to the left. This will make your cut wider then wanted.

Even store bought miter gauges can be a bit loose. If this is the case there's a couple of ways to tighten it up


----------



## Chasing Summer (Apr 20, 2012)

Yes, completely home made. I appriciate everyone's comments as I'm trying to figure this one out.
My track guides are quite long and tight in the slots. I fit each one as I was making them. Then I set it with a carpenters square. I don't think that's the problem. I can see how an out of sqare jig would make the finger slots to wide. The finger slots remain tight on the guide pin.
It seems like each slot grew .001 or so so by the end of 10 fingers they don't line up.
Here's the strange part. All the drawer sides I cut line up with each other, otherwise I would have discovered the problem earlier.
It only happed when I started cutting from the left to the right for cutting the end piece. ..... same set-up ... nothing moved except for the guide pin board to the other side of the saw blade.


----------



## Chasing Summer (Apr 20, 2012)

*pictures on my blog*

I've posted pictures on my blog.
The address is: http://chasingsummer-s42.blogspot.com
Thanks for checking out my sailboat project.


----------



## 27207 (Jan 25, 2012)

Let me start by saying I haven't done box joints before, but I've been reading about them for a while. They seem easy and I'm sure I have a grasp on them. That being said i'm just trying to help you brainstorm this issue. So if I sounds like am idiot i'm sorry lol. 

With your pictures it looks like all if you're cuts are exactly the same, but your fingers are growing on you. The only cause for that is that your pin is increasing distance from your blade. Several things can cause it. to me it looks like the culprit is your clamps holding the fence with the pin. they probably work fine, but as you push the piece against your pin, your fence can slightly move. I've had the same problem with my router fence, I used to clamp it onto my melamine top and it would shift. I fixed it by taping sandpaper in between the fence and top. It seems to have fixed it, plus I don't push so hard against the fence. I suggest resetting your fence, then screwing it together, you can use slots and wing nuts so you can adjust it, or just screw it. Double check the measurements, and recut your pieces. 

You can save your boards too. either make small pieces and glue them into your dados, or just recut as it is (being extremely careful since it won't sit tight on your pin this way), fit it together, then fill in the gaps. I would do it the first way though. the fix won't be too noticeable. It doesn't look like all of your boards/cuts are bad though, so go through carefully measuring them all. You may only need to fill in half of your cuts. 

Woodworking isn't about being perfect, the joy is learning from mistakes and finding ways to fix them. I do it all the time. A few minutes ago I realized I miss measured a mortise. I lengthened it then will fill in the gap after its glued together.


----------



## Chasing Summer (Apr 20, 2012)

*box joint jig*

Concerning the shifting of the pin board on the jig. I thought of that, it's not in the picture. As I final adjusted both the right and left positions I drilled 2 pin holes from the back side so the board can not slip also so the cuts can be easily repeated. The clamps are there to hold the board I'm cutting on the first cut.


----------



## 27207 (Jan 25, 2012)

How is your pin attached? I see that its dadoed into the fence, but is there any type of movement to it or is it pretty firm? Also how are your runners attached? Any way for them to move? If they're just nailed in with pins or staples maybe it shifted? Also check your arbor, if its worn and if the shaft can wiggle in and out, or at all in any direction for that matter.


----------



## 27207 (Jan 25, 2012)

By the way, nice boat. What's the specs on it? Length, year, etc? It looks like you're doing a total overhaul on it with a lot already done. i'm sure when its done you'll love it for years!


----------



## Chasing Summer (Apr 20, 2012)

*The boat*

Thanks for looking at the boat. I need to add more pictures as I've been working forward.
It's 42 ft Spencer built in 1969 at Spencer Boats in British Columbia. I got a great deal on the hull because it had been abandon in a boat yard for over 10 years. I'm getting to own and work with all the woodworking tools I've dreamed of having for years. .... Trouble is, after the boat's done and I set sail what do I do with all my cool toys?


----------



## 27207 (Jan 25, 2012)

Chasing Summer said:


> Thanks for looking at the boat. I need to add more pictures as I've been working forward.
> It's 42 ft Spencer built in 1969 at Spencer Boats in British Columbia. I got a great deal on the hull because it had been abandon in a boat yard for over 10 years. I'm getting to own and work with all the woodworking tools I've dreamed of having for years. .... Trouble is, after the boat's done and I set sail what do I do with all my cool toys?


I can take care of them for you


----------



## Chasing Summer (Apr 20, 2012)

OK .... replace the sink in my motorhome project complete .... time to go back to work on my box joint problem.
It dawned on my yesterday that the blade assembly in my tablesaw, eventhough it's completely tight won't align straight with the fence and therefore out of line with the guides slots. Currently the boards go through the jig on the following board, and are cut left to right. If I turn the jig around and put the boards on the forward side I can cut the proper angle and they will still be cut from left to right. I'll let everyone know the outcome tomorrow. Everyone cross there fingers .... but keep them out of the saw.


----------



## 27207 (Jan 25, 2012)

I hope it works for you! You can cut both on the same side. But the first one up to the pin, and use a spacer for the second one. The last finger on your last board works for this


----------



## Benny Blanco (Apr 21, 2012)

I have been cutting finger joints for speaker boxes and have had error problems.
When I cut plywood, no problems.
Solid woods is where I started to run in to the slots not matching.
The problem I was having was clamping the board tight against my fixture until the board was held flat.
Since most boards ar not perfectly flat, like plywood can be, and error that just keeps compouding itself as you go, can develope.
The boards I am doing are pretty long, too hard to just hold in the fixture by hand.
I arranged a clamp out of wood, that goes in front of the board being cut, with a small raised piece that holds the board just above the blade, only contacting in that small area with minimal pressure.
Trying to keep the board absolutely flat against the back of the fixture was the culprit.
A minimal clamping pressure right above the blade in a small area, letting the board be relaxed made it work for me.


----------



## Chasing Summer (Apr 20, 2012)

*cupping boards*

You're exactly correct. The direction the boards are against the jig they can rock a bit on the board cup. I tried to be careful to roll the board so where the blade was the board was flat to the jig. I only clamped the very first cut where there was no pin support. I think you may be on to something. I'm still going to turn my jig around so I'm cutting the box end board from left to right like I did the side boards. Remember I can't just turn boards at random because I have to take into consideration a 15 degree angle on the drawer.
The back of the draw will be even a bigger nitemare because not only will there be a 15 degree angle but a 45 degree tilt so the back conforms to the hull. I know ... I'm asking a lot for this being the first box joint I've ever cut.


----------



## Benny Blanco (Apr 21, 2012)

This problem I had was driving me crazy, then I snapped to the logic, that the two boards must present the slots to each other straight, even if there is a small curve in the boards.
Once I got them together, I could bottom the fingers in the slots with clamps, at times every clamp I have.
Another problem I run into was, wood glue dries to fast, or I am too slow getting the box togeher, square, and all the fingers bottomed- "more then 40 on a corner". Its much easier the wider and fewer slots, but I like the looks of narrow slots.
I found using a slow cure epoxy glue made it much easier to get the work together.


----------



## Chasing Summer (Apr 20, 2012)

*Box Joint Update*

OK ... week end's over ... new sink installed ... back to work on making my box joints.
As you remember the fingers on the sides, which all match up, didn't match the fingers on the end board.
So, my thought was to reverse the jig so I'm still cutting left to right, which I've done.
Re-check the jig for sqare and that the guide pin is tight. I checked the blade set tight and of course I have not altered the blade pack since I started.
I know, you're all waiting for the outcome .... here it is.
The end board if as flat as you could ask for, so cupping is not a problem. The end fingers still grow so they don't fit the sides.
I made the sides longer so I'm going to cut fingers of one side and re-cut them to see of the sides are the culprit.


----------



## Benny Blanco (Apr 21, 2012)

OK, try this,

Adjust your dado so as the slots fit tight on your guide pin, not too tight, but so the board slips in with absolutly no play on that pin.
What happened to me was, the pin was fitting a little loose, and I was loading the board slightly against it on every cut.
This causes another accumlative error as I was working the slots to the end of the board.
And, make sure no chips get under the board when indexing the next slot.


----------



## Chasing Summer (Apr 20, 2012)

*Thanks all*

Thank you to everyone for the comments and advise.
Due to the cost of wood .... and I want to continue work on my boat, I've abandon the box joints for the time being. I'll try again when I have square drawers to make.
From all comments I think I figured out the problem:
Remember: I'm cutting everything on a 15 degree angle which means the drawer sides, cutting from top to bottom are cut left to right. .... the ends need a reverse set up to cut from top to bottom. Potential problem: I may be as small as .002" off on my setup but compounded over 14 fingers thats .028"
That's significant.
So, when I make square drawers I can cut them all with the same setup.


----------



## Chasing Summer (Apr 20, 2012)

Second Try's a Charm .... 
As you recall I was having trouble cutting pins on angled sides and ends. I cut the sides then turned the jig to cut the ends and the joints didn't fit .... at all.
I've re-built the jig so I can cut both sides and ends on what's actually two jigs attached together so with one set-up nothing moves. Please view my blog to see pictures.
As is said: second try's a charm. The joints worked prefectly the first time ... smooth, not to tight but tight enough.
Thanks for all your suggestion on probable problems and causes.
My next challange will be making one more change. The drawer backs are not only on a 15 degree angle but lays against the boat hull at a 45 degree angle. I'll have to set up a jig with the blade tilted over 45 degrees. The guide pin and spaces will be difficult. Vertically they still have to be approx. 3/8". On the angle they will be much wider.
I've added pictures to my album.
Look for posts on my blog: http:chasingsummer-s42.blogspot.com


----------

