Lap joint on end of 2x4?

[J. Clarke]

Just put it up on flickr--an account is free.

[J. Clarke]

I'm curious as to the treatment--almost all pressure treating of construction lumber involves copper compounds and almost all copper compounds are green. Brown pressure treat would usually be creosote, which would go in railroad ties, marine pilings, and a few other uses. The stuff is sticky and has a distinctive odor and is generally not used for light construction.

If it's "partial treatment" it's crap. The dark brown treatment is a coloring for deck lumber and other uses where the lumber will not be painted and is in addition to the preservative--it's no more a preservative itself than an application of Minwax is a preservative, it just goes deeper so won't go away the first time you clean the deck with a pressure washer. The only brown preservative in common use is ACQ-D IIRC, and it's a light brown, not dark.

Does your lumberyard stock two kinds of pressure treated lumber, one to "sit on the ground" and the other to be cut up to make decks and the like with through-holes for fasteners?

In any case, lumber rated for ground contact generally has a heavier treatment than lumber not intended for ground contact.

[Winston]

Hokay, Morris.

Watch your inbox.

--Winston

[Winston]

On 4/27/2010 6:47 PM, Larry Jaques wrote: (...)

OK. Thanks, Larry

--Winston

[Morris Dovey]

Thank you. I can't really tell how much is protected. If ugly will do the job, then that stick should last forever!

[Winston]

Exactly.

That was one of the very few *good* looking pieces that I selected out of the HD stack.

Oh Well. It just has to work structurally.

Thanks.

--Winston

[Mike Paulsen]

Minnesota. The local Menards and Home Depot both stock treated 1x4 and 1x6.

[Robert Bonomi]

Awright, wiseacre! You *do* know that somebody actually makes a hand circular saw with two *counter-rotating* blades on it, don't you?

No, you do _not_ need flat. Consider a dovetail joint -- no flat surfaces whatsoever. The _only_ requirement is that they mate up well.

The _easiest_ way to ensure a good mating it to make both surfaces flat, but it is -not- a requirement.

[Larry Jaques]

On Tue, 27 Apr 2010 18:26:54 -0700, the infamous Winston scrawled the following:

Is it sprayed on? Now you know why you don't buy wood at Homey's Despot.

Send the pic! You have my addy.

-- Losing faith in humanity, one person at a time.

[Larry Jaques]

On Wed, 28 Apr 2010 00:35:39 -0500, the infamous Mike Paulsen scrawled the following:

Amazing. I'd never heard of them before, let alone seen them. In doing more research on it, I found out that AZQA is used on Doug Fir. I hadn't thought that species was PTed.

-- Losing faith in humanity, one person at a time.

[Tom B]

That is what I'd do in your shoes... a flatter bottom and if your routing guide is clamped square to the pieces, a nice fit. Make a couple practice cuts to achieve the proper depth to wind up with both pieces (joined) on the same plane. Be aware cross grain joints don't do well with glue alone over time... peg, dowel, or screw them as well. Tom

[Tom B]

Braggart! I wish I had your abilities! Tom

[Winston]

Copy that, Tom.

I've tried lateral cuts with the skilsaw, chipping and chiseling. My second attempt looked a *lot* better than my first attempt.

Neither gave me the great looking step provided by the router. Each attempt took about the same amount of time so it's an easy decision even though the router approach is noisier and messier.

I will have at least two wood screws through each glued lap in the corners so I'm pretty confident that will be sufficient.

As Larry says, I would be well advised to provide some kind of enhanced diagonal support, like aircraft wire to address sag. I am still pondering how to make that brace look a little less clumsy than they normally do. Perhaps I will epoxy a couple

1/4-20 standoffs inside some 1/2" steel tube and then paint it thoroughly.

Hmm.

Thanks!

--Winston

[Morris Dovey]

It's not much a matter of abilities - I really wanted an accurate joinery machine to compensate for my _lack_ of abilities.

It was a matter of making drawings (a lot of drawings) until I had a design that, if I could build it, would be inexpensive and do what I wanted. That took a while...

One of the things that no one seems to notice is that there are relatively few critical dimensions in the wooden parts. :)

Even so, by the time I was done I'd made all of the wooden parts _at_ _least_ three times before I had 'em right...

The motors and electronics, and the controller software were all off the shelf - the results of _other_ peoples' abilities.

The only thing I can really brag about is sticking with the project until it was done (I _almost_ didn't).

[Winston]

(...)

didn't see a BOM, dimensioned drawings and assembly /setup instructions for your JBot, Morris.

You are selling the CD with all this on it for $24.95, yes? A 'wood parts' kit for $129.95? Full mechanicals kit, minus the motors and electronics for $449.95?

Link?

--Winston

[Morris Dovey]

Drawings were posted to ABPW as soon as the design was finalized, and photos were posted to my web site as each part was made and installed. What you see on the web site today are just a few of those photos.

[Chris Friesen]

Actually a dovetail joint is a bunch of flat surfaces that all mate together. :)

Chris

[Jack Stein]

J. Clark is right. Here are 3 pictures of wolmanized 2x4 and a 2x6 I had laying around my shop. These are above ground pieces, not rated for below ground use and whether the pictures show it well or not, I can tell you the treatment is all the way through. The 3rd one shows the heart wood is a different color but the treatment is throughout, and not just he first 1/4".

This is standard wolmanized lumber, can't say where I bought it but probably 84 lumber, a lumber yard.

If it's dimension lumber and it's not the same color all the way through

I'm pretty sure PT wood must be green when treated. If it is dry, the treatment won't penetrate as it is some sort of hygroscopic hocus pocus that is going on?

[Winston]

(...)

--Winston

[Winston]

(...)

That doesn't look anything like the bargain basement sticks I'm working with.

--Winston