Dowels - how tight is tight?

[Jim Mackell]

I've never used dowels to any extent. Now I have a project that will require me to use numerous 3/8 dowels for joining. In preparing the wood I've used a 3/8 bit in a drill press and each hole is exact. When test fitting the dowels they are extremely tight and require a good rap with a mallet to properly seat. Not sure of the brand name of the dowels but they are the type that has a spiral groove to help spread the glue. I also microwaved them for 60 seconds to remove any moisture.

How tight should a dowel fit in a properly prepared hole? Very tight? Tight? Can be twisted by hand?

Thanks for any input!

Jim

[Glen Butler]

I don't like them so tight that I can't pull them out by hand. I want to be able to work quickly with them, and having to pick up a mallet defeats that. They should be snug though, with no noticable jiggling in the hole. You may need a different dowel, or you may want to get the next size up of bit. Sorry I don't have my starrett chart on me right now so I cannot tell you if there is a drill size a couple thou bigger than 3/8"

[Wade Lippman]

Depends on how hard you have to hit them. If they are too tight to just push in, but need a tap, then they are perfect. If you have to really hammer them, then they are probably too tight.

Dowels are rarely truly round; if they go in too easily than they aren't in contact on much of the dowel.

[Jim Summers]

I don't like them so tight that I can't pull them out by hand. I want to be able to work quickly with them, and having to pick up a mallet defeats that. They should be snug though, with no noticable jiggling in the hole. You may need a different dowel, or you may want to get the next size up of bit. Sorry I don't have my starrett chart on me right now so I cannot tell you if there is a drill size a couple thou bigger than 3/8"

I like mine to be able to push them in and take them out by hand. I am pretty sure the drill bits that come with the dowelmax are 9.7mm, and then using the 3/8 expansible dowels.

I also microwave the dowels in 45 second increments 2-3 times depending on how many I am doing.

HTH

[Leo Graywacz]

I go 1/64" over on my holes for dowels. Never had a problem yet.

[Bill Huber]

I use a lot of dowels with the DowelMax and I use the expansible dowel from Lee Valley. I use the 9.7mm drill that came with the DowelMax and the dowels can be pushed in with you thumb but once glue hits them, they swell up and become very tight.

Once I was using them and the humidity was very high and I put some dowels in and let them set for awhile, while I was doing some other things and when I came back to glue things up I had to use pliers to pull them out.

So you want to keep these dowels in an air tight container, I use a jar with a good lid.

[glenn bradley]

In the immortal words of Sam Maloof "Leave room for the glue".

[Kent A Bathurst]

I go 1/64" over on my holes for dowels. Never had a problem yet.


Bingo....

asdf

[Dan Forman]

3/8 is .3750" Next up from that is 25/64, which is .3906" If you want to split the difference, you can use a "W", which is .3860". Drills are cheap, I'd get one of each and see which one fits better. My drill chart is hanging on the wall by the drill press, and gets a lot of use. One of the handier things to have around.

Dan

[Charles Wiggins]

I like mine to be able to push them in and take them out by hand.

I'll second that. I like them just snug enough so they don't fall out, but not so snug that I cannot pull them out with my fingers. Then when the glue is applied they either slip right into place or a light tap from the mallet will do it.

[Prashun Patel]

In my experience, the 'tightness' of my dowels is more a function of my dowels - not the hole I'm drilling.

I find life is much easier since I made a dowel plate. Drill a hole in a piece of rigid sheet metal like a mending plate. Don't ream the edges. You want them nice and sharp. Then drive your dowels through that before putting them in the hole.

[Harold Burrell]

I take a more natural approach to this...

First, I drill the holes. Diameter is not important.

Then I fill the hole with dirt.

Next I plant whatever species of tree/wood I want for a dowel.

I then clap the corresponding pieces together and set them aside, waiting for the dowel to grow.

It usually takes 4-5 years.

[Tom Esh]

The next size up is a "V" (.377"). Unless they're pretty worn, the DM guides won't accomodate "W" or larger. The moisture content of the dowels can cause a lot more variance but it's pretty easy to deal with. I toss 'em in a 150 deg oven for a couple hrs or overnight in a ziploc bag with a dessicant dryer.

[Barry wines]

I have noticed that most dowells that you buy in hardware stores or in the big box stores are slightly over size.(up to .005"). In most cases a press fit is not necessary because when you put glue on them they swell slightly and it makes them difficult to install. If you use dowells that match the size of the hole and then glue them they should be just about right.
If your dowells are over size you can sand them down in a drill press or better yet buy the A2 steel sizing plate that Woodcraft sells. I don't have one yet but am tempted to buy one. Hope my two cents worth is helpful.

[Leo Graywacz]

I have noticed that most dowels that you buy in hardware stores or in the big box stores are slightly over size.(up to .005"). In most cases a press fit is not necessary because when you put glue on them they swell slightly and it makes them difficult to install. If you use dowels that match the size of the hole and then glue them they should be just about right.
If your dowels are over size you can sand them down in a drill press or better yet buy the A2 steel sizing plate that Woodcraft sells. I don't have one yet but am tempted to buy one. Hope my two cents worth is helpful.

Not in my world. That is way to much time consuming work. If you are a hobbyist good chance that will work for you. But when you are making money off of this you can't be sanding dowels or putting them through a die or anything like that. If you use a 25/64" drill that leaves .0078" on either side of the dowel for glue. And while that is a little large of a space for the glue it will work more than adequate for that function. Plus if you are doing rows of dowels and you only have a few thousandths tolerance on your holes all you have to be off is a few thousandths and you won't be able to push the pcs together.:mad:

[Jim Mackell]

Appreciate the replies. I've taken the dowels I'm working with, chucked them in my cordless and just touched them up with sandpaper. Does the trick quickly and nicely.

[Peter Quinn]

Thats what I do at home Jim, but in the drill press. I like about .008" difference between dowel and hole, give or take a few thousands.

At work we use thousands of dowels, and we buy them custom milled undersized. I think we use .490" dowels and drill the holes with a three head line boring machine. No sanding or dowel plates necessary, but the minimum dowel order is like 10,000 pieces. If you need pliers to pull them out dry, thats too tight. If they fall out dry, thats too loose.