Lag Screw Pilot Hole

[Jim Summers]

Hello All,

I am pretty sure poplar is technically a hardwood. But to me it is a little on the soft side of hard. I was looking at recommended pilot hole sizes for 1/4" lag screws in wood and it recommends:

3/16 for soft and 7/32 for hard.

Will a 32nd matter much, if I do not have a 7/32nd drill bit?

It is just going to hold a fence to a sled. Actually the front fence, so there shouldn't be any pushing or pulling, just twist resistance.

Ideas?

Thanks

[glenn bradley]

I don't think you will have a problem in poplar. Just follow the general guidelines for large fasteners; adequate pilot (as just discussed, poplar is physically pretty soft), hole depth a bit over the connector's length (you don't want a 1/4" shaft forcing its own hole I also sometimes slightly countersink the pilot hole where the two surfaces will meet to avoid 'creep' caused by volcano-ing the holes rim.

All that being said, all my 1-1/2 to 2" thick front fences on 3/4" thick sled bases are held with glue and #8 screws.

[Neil Brooks]

Big fan of this sort of info. Lots of these things ... I've printed out, and put in a 3-ring binder, under my bench:

http://www.internetwoodworking.com/w5/screws.html
http://www.engineershandbook.com/Tables/woodscrewpilotholes.htm
http://www.engineeredpartsinc.com/pilot-hole.htm

[Joe Angrisani]

One of those times where I gotta say it:

Jim... You know being a hardwood and being a softwood has nothing to do with being hard or soft, right?

[Greg R Bradley]

hardwood comes from deciduous trees, softwood comes from conifers.

[Jim Summers]

One of those times where I gotta say it:

Jim... You know being a hardwood and being a softwood has nothing to do with being hard or soft, right?

Ummmmmm. I tell ya' when I was writing the OP I was thinking to myself, "This one may eventually get mod'd or deleted if it takes a wrong turn!"

[Dick Brown]

My Dad, who would be 111 if he were still alive, told me his dad said "You drive lag bolts in with a hammer! The treads are for taking them out!" They had cordless drills back in the 1800's so I don't know why they didn't drill pilot holes!! L.O.L.

[Forrest Bonner]

Check out McFeely's. They sell a lot of fasteners for wood and have tables for screws, lag blots, etc/
Forrest