Straight Edge to Cut Door

[Buck Turgidson]

Probably a silly question, but it has been bugging me. I need to trim about

1/8" off some door slabs that I am installing. I'd prefer to cut rather than plane or sand.

The problem is finding an 8' board that is straight. I thought I found one only to find that either it warped on the way home from Home Despot, or I am blind.

I have tried fake wood panel trim, only to find that most of it is not straight either.

Can someone suggest an economical material or product that is reasonably straight enough? I have seen a fancy saw guide that Tommy Silva used, but not sure I wanna sink the bucks into it.

[A Dubya]

...a piece of dry wall ...?

[Swingman]

Most economical is the factory edge of a sheet of plywood ... it should be straight enough for your purpose and a bit of lengthwise bow won't hurt because you will be clamping it securely to the door. The problem with using it as a saw guide is placing it the precise distance back from the proposed cut line, but it can be done with precision if done carefully.

Next step up is to make a saw guide out of 1/4" plywood and the straightest angle aluminum of sufficient length that you can find.

Simply attach, with counter sunk bolts, the aluminum to the plywood, cut purposely wider than the base of your circular saw on the overhang side. Then run the circular saw along the aluminum guide, cutting of the excess plywood ... the resulting edge can now be used to line up with your proposed cut line on the door and you will be assured of reasonable precision.

Next up is one of the commercial saw guides.

[RB]

I'm trimming about 20 solid core doors now and have found that the easiest way to do it is to use a router with a 1/2" roughing end mill.

Three passes is easiest for me, about 1/2" of depth with each pass.

For a straight edge to guide > Probably a silly question, but it has been bugging me. I need to trim about

[Buck Turgidson]

This is the method that I am using, except for a 1-by board instead of alum. I'll look into finding some alum. Or perhaps the factory edge of plywood, over top another piece of plywood.

I also have considered using the old door itself, since it seems pretty straight.

[Dan Baker]

I've used a drywall T-Squre with pretty good success. Just use some clamps on each end to hold it down.

[Leon]

Use one of the other doors as your straight edge.

[Eric Scantlebury]

For about $15 bucks you can get a circlular saw guide at the Borg. That's what I did. It's made specifically for this type of job. It's aluminum and just clamps to the door slab. I can't find one on the Home Depot web site (Then again I can never seem to locate anything on their website) - but I purchased one there. It is similar to this:

[mttt]

MDF - nuthin' straighter. At 19 bux, it's cheaper than plywood here (albeit heavier). Also - it's 97 inches, an extra inch for clamping.

[Buck Turgidson]

Thanks. I'll look at using some MDF for a straight edge. I still prefer to use a straight edge in a "saw board" type jig as Swingman described above, rather than using it directly, since I can quickly see exactly where the cut line is, rather than eyeballing it.

[Tom]

Buck's right about Swingman being right. And the shoe of the saw won't mar the door that way. Sawboard. Someday, it'll all be over....

[Buck Turgidson]

I cut the first door using the sawboard and a 40 tooth finish blade. Looking at the cut off sliver, I couldn't tell which was the factory side and which was the cut side. Got a nice 3 degree bevel on it, too.

If only it had been perfectly straight....

[xrongor]

a string will get you a nice straight line, wont take up much storage space in the garage, and you already have some.

randy

[Pat Barber]

MDF with a 1/4" plywood base will work just fine. I would use 1/2" mdf. I belive that sells for around $12 a sheet.

Buck Turgids> Probably a silly question, but it has been bugging me. I need to trim about

[J. Clarke]

Kind of hard to find string that you can pull tight enough to be able to use it to guide the saw though.

[John]

Find a 8ft length of heavy aluminum angle, OR 8ft lenght of steel stud and use that as a straight edge.

Of course, running it thru a tablesaw using the fence will do the same thing, probably more accurately, and a whole lot less hassle

Other option would be a length of Melamine shelving in 8ft length

John

[Pat Barber]

[Buck Turgidson]

[CW]

[Paul Franklin]

The factory edge of hardwood plywood is usually pretty good. Or why not use another one of the doors?

Paul