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Forum topic by Micah posted 10-14-2021 11:01 PM 501 views 0 times favorited 15 replies Add to Favorites Watch
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Micah

58 posts in 521 days


10-14-2021 11:01 PM

Hobbyist woodworker here with a question that most of you guys will almost certainly consider basic knowledge, but I’m lost and I need some guidance.

I bought a set of plans from Rockler for building an Adirondack Bench. It came with a number of cardboard templates (which I’ve used to create a set of more durable 1/4” MDF templates), and it also came with a sheet of paper containing ‘Shop Drawings’ that provides the dimensions of several pieces of the Adirondack Bench. But I’m not exactly sure how to interpret these drawings. The scale/ratio is throwing me off a bit.

Also not entirely sure how I’m suppose to use this scale to determine the locations of the countersunk pilot holes that I’ll use to connect these components together with the rest of the bench (*these can be seen in the image below as tiny ‘dots’ on the yellow colored wood in various locations.

How am I suppose to know which piece of wood from the provided lumber list I’m suppose to use to cut each element shown in these shop drawings?

I’d really appreciate it if someone could please help me make sense of this all? Thanks so much!


15 replies so far

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Loren

11314 posts in 4934 days


#1 posted 10-14-2021 11:26 PM

An architect’s triangular rule can make reading or making scale drawings easier.

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Micah

58 posts in 521 days


#2 posted 10-15-2021 04:39 AM

I just realized the image I attached to my initial post isn’t able to be enlarged enough for anyone to offer any real help. You can view the full size Shop Drawing at the following link (hopefully this helps you guys enough so that you can help me!)

https://www.dropbox.com/s/suhrj2j7lkzqb1r/IMG_0202.jpeg?dl=0

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Madmark2

3158 posts in 1875 days


#3 posted 10-15-2021 04:55 AM

ULHC says: SCALE: 1/4” = 1”

Everything needs to be enlarged 4x.

-- The hump with the stump and the pump!

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bilyo

1422 posts in 2389 days


#4 posted 10-15-2021 02:31 PM

As said above, the information in the upper left of the drawing tells you that a measurement of 1/4” on the drawing equals 1” on the finished piece. So, the finished piece will be 4 times larger than what is on the drawing. Look at piece number 6 at the top and note that the information below it says that the finished piece is 2 1/2” wide. Now note that piece number 6 is 2 1/2 grid spaces wide. This means that each grid represents 1” and, since the drawing is 1/4”=1”, the drawing grid equals 1/4”. You can prove this by laying any ruler on the grid to find that they equal 1/4”. To find the locations of the holes, lay your ruler on the plan and measure the locations from the edges of the piece. For every 1/4”, you measure, the finished location will be 1”. In other words, multiply by 4. if you measure 3/8” on the drawing, the actual distance will be 1 1/2”. I hope this also answers your last question.

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Rich

7569 posts in 1876 days


#5 posted 10-15-2021 02:45 PM

The architects rule mentioned above will eliminate the need to multiply by the scale factor, which should reduce the likelihood of getting something wrong.

-- Half of what we read or hear about finishing is right. We just don’t know which half! — Bob Flexner

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Lazyman

8260 posts in 2674 days


#6 posted 10-15-2021 04:27 PM

No reason to overthink this. Verify that the grid is actually 1/4” to make sure it is printed accurately then take a measurement with any ruler and multiply it by 4.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

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bugradx2

353 posts in 1306 days


#7 posted 10-15-2021 04:35 PM

knowing the scale conversion as outlined from other folks comments would also allow you to take this to a print shop and have them blow it up for you. If printed at full scale each box would measure 1 inch by 1 inch. You could make your templates from there if needed.

-- The only thing not measured in my shop is time

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Foghorn

1353 posts in 673 days


#8 posted 10-15-2021 04:35 PM

A scale ruler is not a direct translation if the drawings have been reduced or enlarged. Lazyman’s suggestion is the easiest if the printed grid is actually 1/4”. Otherwise, some simple math based on what the actual grid dimension is.

-- Darrel

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LesB

3143 posts in 4730 days


#9 posted 10-15-2021 04:50 PM

Don’t get focused on the scale. The grid pattern on the drawing is equal to 1” squares and the real dimensions are given for each piece. To place your counter sunk holes just count the number of grid squares from the end and side to get the X-Y position for the hole in inches on the actual piece. X-Y refers to the horizontal and vertical measurements.

If you are purchasing lumber what you need to know is the total number of board feet you need plus the various lengths and widths that need to come out of each piece. One method I use to get the most use of say from a sheet of plywood is to draw out all the pieces I need for the project to see how they fit on a 4X8 sheet. I do this with a computer cad program but you could do it cutting scaled pieces of paper. You can do a similar method for pieces of lumber. Sometimes you will find it is better to buy say a 1”X8” board and other times a 1X4 or 1X10 will produce the least waste/scraps.

-- Les B, Oregon

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controlfreak

3063 posts in 888 days


#10 posted 10-15-2021 05:08 PM

Never trust a printed scale, if anyone has ever changed the print format you are done for. Architects in the early days of PDF’s used to intentionally do this to screw over anyone who reproduced their plans with out buying them. In the end it screwed over their own buildings enough to where they stopped the practice. To this day I always find a 3’0” door to check the scale.

As said just get a scale rule or use a regular rule to get your bearings and go to it. Scale rules are cheap and can bypass some math errors if the plan scale is accurate.

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MrRon

6213 posts in 4530 days


#11 posted 10-15-2021 06:20 PM

I would cut the wood as shown on the drawing, and that’s it. The orientation of the pieces will tell you where the nails/screws go.

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LesB

3143 posts in 4730 days


#12 posted 10-16-2021 05:45 PM



Never trust a printed scale, if anyone has ever changed the print format you are done for. Architects in the early days of PDF s used to intentionally do this to screw over anyone who reproduced their plans with out buying them. In the end it screwed over their own buildings enough to where they stopped the practice. To this day I always find a 3 0” door to check the scale.

As said just get a scale rule or use a regular rule to get your bearings and go to it. Scale rules are cheap and can bypass some math errors if the plan scale is accurate.

- controlfreak

Why would Rockler include a scale drawing that “intentionally” included errors? Not good for business….
The dimensions are written on the drawing and all you have to do is count the scaled grid to confirm they are accurage.

-- Les B, Oregon

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MrRon

6213 posts in 4530 days


#13 posted 10-16-2021 07:23 PM

I don’t trust drawings by others. On 2 occasions, using plans, I found errors that had I followed would have resulted in the project not turning out right. I use Autocad© to produce all my own drawings. Dimensions are integrated with the images so as long as the image is correct then the dimensions are also correct.

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ManySplinters

25 posts in 66 days


#14 posted 10-16-2021 09:05 PM

But I m not exactly sure how to interpret these drawings. The scale/ratio is throwing me off a bit.

Also not entirely sure how I m suppose to use this scale to determine the locations of the countersunk pilot holes that I ll use to connect these components together with the rest of the bench (*these can be seen in the image below as tiny dots on the yellow colored wood in various locations.

How am I suppose to know which piece of wood from the provided lumber list I m suppose to use to cut each element shown in these shop drawings?

Fortunately, it looks like those drawings do contain the actual measurements too. I’ll focus on the bottom part, 3A.

It’s 46 inches long, or 46 squares (where a square = 1 inch). The width is harder to see since it includes a full square and a partial square that is less than half. So 1 inch and almost a half inch wide. The drawings tell us it’s actually 1 and 3/8’s wide, so our eyeballing the squares was pretty close.

That’s what you’ll have to do to locate the pilot holes – eyeball the partial squares and you’ll be close. So on 3A again, looks like the left pilot hole is 1 square and then maybe a quarter of another square. This would equal 1 and 1/4 inches. Same on the right. The middle is exactly 23 squares from the left (or right). So that would equal 23 inches… My guess is that the parts you’ll be attaching it to will have plenty of material and if you’re off an 1/8th of an inch it really won’t matter. But I’m just guessing there.

Identifying where the parts come from or how they relate to the materials list is tricky to figure out without seeing the full set of plans. (don’t post them here of course) I looked up the plans for sale on their website though and it invites people to call for expert advice. I’d take them up on it.

Good luck! :)

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Mike_D_S

808 posts in 3501 days


#15 posted 10-17-2021 04:34 PM

A lot of the advice above is good. But at the end of the day if this is one of your first times building from scaled plans, the advice above about taking it to your local print shop (or Fedex/Kinkos) and getting it blown up so that you have full size plans may be the easiest.

It may cost you $15-$20 to get it done, but then you’ll be able to focus on doing the work rather than sweating whether you measured right or not from the scaled down drawing.

As a side note, make sure you tell them that the squares in the final scaled print should be 1” x 1” rather than just telling them to blow it up “4x”. They do it for a living and should be able to scale it in two axis as required.

-- No honey, that's not new, I've had that forever......

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