calling all woodworkers

[goaliedad]

I need some help- I'm building some bookcases with adjustable shelves. I'm using 1/4 inch pins. The first case I used a piece of peg board for a guide- turned out fine. As I am building a number of these, and the peg board was starting to wear down I bought a DrillRite Shelf Pin Jig.
Well, on my first attempt I was happy with the first side- made sure the starting ppoint was even for the second side. On a 6 foot run, the top holes were off 1/4 inch! I went back and could not find any one spot that I messed up. On the second side I was off about 1/8 inch.
As the jig has two sets of holes- different distances from the edge, I redid the first side, and was again off about 1/8 inch. I think I can live with this.
I'm pretty sure there is just enough slop in the jig that over a distance there will be some difference- but any help is much appreciated.

Thanks in advance

 

[dieselsmoke1]

Probably the best non technical solution (read expensive) would be to reindex the drilling pattern more frequently.

If you're using pegboard for a guide, I'd guess your target boring pattern is 1" oc. Does not matter, only thing that changes is the math.

On each linebore, mark alignment points from the bottom of the end panel every 10" or so. Always measure all the way from the bottom, not to the last hole bored. Realign to center these points each time you reach one. With a little care this should keep the hole pattern within about 1/32nd or so.

Hope this helps. Good luck.

 

[goaliedad]

good idea- I am not using pegboard anymore as it does not hold up well after several uses- that's why I went with the jig- but your idea will work there as well.,

 

[GeneD14]

If you are going to make multiple sets of shelves here is an idea:
Use a plunge router with a 1/4" bit and a template guide bushing so the holes in your template do not get wallered out. You just have to lay out the holes accuritely once on the new template and make them the size of the template guide bushing.

Here is a link that tells one way to do this:
http://www.woodworking.org/WC/GArchive99/4_23holejig.html

 

[gsganzer]

I don't know how you'd fix the holes that are misaligned, other than router a groove and install a shelf standard in their place.

 

[goaliedad]

Thanks for the link. The guide I have is made of plasitc and has a self centering ( bushing ) drill bit- you drill a series of holes then move the jig and put a pin in one of the holes to keep everything aligned. I think the problem is that the jig is only about 16 inches long- so you have to move it several times. there is a vey small amount of slop when the pin goes in- if the jig is pulled one way consistantly that small amount of slop adds up.

As for fixing the first run I am going to rip the bad portion off and glue up a new piece. Not ideal, but it will work.

I could take the time to make a jig that is full size, but thought buying this was a better option. In the future I am going to make sure that I am not pulling the jig tight to the pin and checking everything as I go.

Any more ideas are still welcome.

 

[Jarrett]

Thanks for the link. The guide I have is made of plasitc and has a self centering ( bushing ) drill bit- you drill a series of holes then move the jig and put a pin in one of the holes to keep everything aligned. I think the problem is that the jig is only about 16 inches long- so you have to move it several times. there is a vey small amount of slop when the pin goes in- if the jig is pulled one way consistantly that small amount of slop adds up.

As for fixing the first run I am going to rip the bad portion off and glue up a new piece. Not ideal, but it will work.

I could take the time to make a jig that is full size, but thought buying this was a better option. In the future I am going to make sure that I am not pulling the jig tight to the pin and checking everything as I go.

Any more ideas are still welcome.

It sounds like the jig you bought would work good as long as there's no slop in it. It uses the same principle as the line boring machine my Dad has in his cabinet shop. You drill a set of hole, slide the board down and set the alignment pin in the last hole drilled and drill the next set. If I were doing it without a line boring machine or a good jig, I'd just measure and mark out all the holes very carefully and drill on a drill press. Or, like a previous gsganzer said, route/cut or dado in and use shelf standards.

 

[gsganzer]

Here's a shelf standard that's decorative.

 

[kennyd]

I made my jig out of 1/2" MDF. I used the drill press w/fence to drill 3/8" holes at 1 1/4" on center. I used a index attached to the fence to insure the holes where exactly spaced.
Then I use my plunge router with a 1/4" bit, and a 3/8" bushing installed in the router base.
Using a router ensures the holes are perfectly straight, and the is absolutely no tear-out around the hole using this method. And the jig does not wear out.

I am currently building an entertainment center now, and just used it the other night...can post pics if you need them to understand better...

 

[goaliedad]

Thanks for the input- I think I am going to break down and make a jig for the full length- I have about 6 more cases to make so it will be worth it. The jig I bought is great for a short run, but looks like it is going to be a problem for the length I need.