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Check out the March 9, 2013 issue and see if this is of interest to you. Sign up to receive Chiefwoodworker's Newsletter by entering your email address below. (Privacy Policy)


Completed StandI recently finished a four part post to my American Woodworker blog site titled The Book of Shaker Furniture by John Kassay – A Treasure Trove for SketchUp Generation Woodworkers. This series of posts demonstrates how to create a 3D model based on 2D drawings from any woodworking book or drawings. The specific piece is a Shaker Round Stand pictured at right. If you wish to learn how this piece was modeled in SketchUp and shop drawings created you can follow the links below:

  1. The Book of Shaker Furniture by John Kassay – A Treasure Trove for SketchUp Generation Woodworkers – Part 1
  2. The Book of Shaker Furniture by John Kassay – A Treasure Trove for SketchUp Generation Woodworkers – Part 2
  3. The Book of Shaker Furniture by John Kassay – A Treasure Trove for SketchUp Generation Woodworkers – Part 3
  4. The Book of Shaker Furniture by John Kassay – A Treasure Trove for SketchUp Generation Woodworkers – Part 4

If you wish to build this stand you can go to my Free Plans page (menu), look in the spreadsheet under Tables for Shaker Round Stand. Click the smiley face in the SketchUp column to download the SketchUp model and shop drawings. You can print out a full scale drawing of the pedestal and leg used in this piece to create templates for the shop. If you have trouble printing to scale in SketchUp see my post Printing To Scale With SketchUp Make & SketchUp Pro 2013. The techniques used in this post also works for SketchUp version 7 & 8.


Student's Shop Made RisersA student wrote me asking how he could make a SketchUp model that realistically represented a project he built in the shop. The project is a lampshade constructed of four L shaped risers and horizontal stretchers.

In the shop he started with four risers, each glued up to produce the L shape. He tied two sets of the risers together with a stretcher. The results are in the picture at left.

The student didn’t share his thoughts behind his question with me, so what follows is my interpretation of what he may have been thinking.

He may have wondered why the left and right sides of the L were not 90° to the sides. Being curious he may then have produced a SketchUp model, perhaps to answer his question. The SketchUp model produced desirable results as seen below right. Clearly all the side are right angles. He wondered why the difference and asked if I could produce a model that represented “reality” – i.e. the shop version.

Student's SketchUp ModelThe simple answer as to why these models are different is that he built the shop model and the SketchUp model differently. The shop model started with glue ups at right angles and roughly 1” on a side and 3/8” thick. He then made a compound cut to allow the risers to tilt inward in both the x and y direction.

The problem is that when you tilt the risers in both direction and then tie them together with a stretcher, which itself is tilted inward, you force the other side to point inward. Further, when you cut the L shape with a compound angle you produce a cross section that is not rectangular, but rather parallelogram in shape. You can see this nicely in the photo thanks to the glue lines. Click on the photo to enlarge it and look at the pieces joined together to form the L.

So why did the SketchUp model look so nice and provide the desirable results? The answer is found in a quote from the email he sent me.

SketchUp Model:  To make the vertical risers – drew the bottom (L-shape) as a horizontal plane, drew a second "L" and moved it up and out, and then connected the corners.

He essentially made the assumption that a compound cut would produce a cross section with right angles, that is, rectangular in shape. He then produced the cross section he wanted and copied it at a higher elevation and shifted it inward in both x and y direction. Finally he connected the corresponding corners to form risers. A detailed inspection of the resulting riser would reveal that the angle between the outside faces would have to be greater than 90°; not by much. In fact little enough to deceive the eye.

I constructed a riser using this right angle assumption just as the student did. It was 1” wide on the outside faces, 20” high and tilted in 3” in x and y. The angle between the outside faces I measured to be approximately 91.3°.

Chiefwoodworker's SketchUp Model Of Shop ImageI then constructed a SketchUp model using the shop model approach. That is, I started out with L shaped risers that was all right angles. Then I used slicing planes to cut the top and bottom just as you would do with a compound miter saw. Then I rotated the risers in the x and y direction to align the compound cuts with the ground plane (red/green plane) and achieved the desired tilt. The resulting picture is at left.

This model is tilted a lot to demonstrate what happens. The only reason this model does not look exactly like the shop picture above is because I did not tie riser sets together with stretchers and force the front and back faces to align. If I had the side faces would be angled in even more. You can download this model and convince yourself that the risers are in fact constructed from right angle stock and compound mitered at the ends.

Compound miters, or more generally, faces that are at angles to two planes, are a difficult problem for most people starting out with SketchUp to master. If you have taken my beginner’s and intermediate SketchUp courses you have heard me talk about slicing planes. This problem begs two questions: how do you create the correct compound slicing plane to achieve the desired splay and what angles do you set your table saw, or compound miter saw for when cutting them. I will answer the first question in the attached video below. The second question is the subject of a subsequent post. Stay tuned.

A Related Tutorial Video – Drawing Tapered & Splayed Legs

Drawing Tapered & Splayed Legs is a related tutorial video you may also be interested in.

Viewing The Video

You can view Drawing Compound Miter Faces In SketchUp by pressing the play icon below or by downloading it to your system.

The video file is mp4. It can be viewed with most video players including QuickTime and Media Player. If you have a default, or user specified, file association for .mp4 you may have to delete it or use a download manager to download this file. Otherwise the associated application may be invoked and file streaming will prevail over downloading. There are numerous free download managers on the internet. Be careful, and do some research to locate one that is not loaded with spyware or viruses.

If you are on a PC platform running Windows OS and have Internet Explorer or Firefox you don’t have to change file association or use a downloader. Simply right click on the link(s) below and choose Save Link As. When Explorer opens choose a destination folder and select Save.

To download Drawing Compound Miter Faces In SketchUp or paste

http://www.srww.com/downloads/blog_posts/Drawing%20Compound%20Miter%20Faces%20In%20SketchUp/Drawing_Compound_Miter_Faces_In_SketchUp.mp4

into your download manager.

Full Screen Viewing

You may find it easier to view the video in full screen mode. Start the video before selecting this mode. To enter full screen mode click the little screen icon at the bottom of the video player. When in full screen view hold your cursor near the bottom of the screen to access the video player’s controls. Exit full screen mode with the Esc key. Sit back, relax and enjoy the show!


One of my students wrote me enquiring how to draw tapered and splayed legs. He was trying to use the usual technique starting with a square representing the cross-sectional area and extruding it to the legs height.  Tapered and splayed legs are tricky to draw because of the compound angle the top and bottom of the leg are cut. The usual way of drawing a tapered leg can be used, but when the legs are then splayed in two directions you run into numerous problems with Rotation and Push/Pull operations. Unless you were an A+ student in high school geometry class and can visualize complex rotations in your head,this is a difficult way to proceed.

Tapered & Splayed LegsAn easy way to draw these legs is to treat them as the intersection of two parts; each an extrusion, one from a front view and one from a side view. This can be done with the Intersect Faces tool. This video demonstrates this technique.

As you watch the video there is a portion of it where I run into problems because of SketchUp’s difficulty in dealing with very small entities. I stumbled and eventually found a work-around. I chose not to edit this out because I thought it a good learning experience for both you and me. I did add a subsequent section to the video to show a better approach. So I apologize for the rather amateurish resulting video, but the teaching and learning moment I couldn’t pass up.

This also points out one of the tenets of drawing in SketchUp. Think ahead! If I had practiced this tenet on this particular occasion I would not have run into this problem.

Viewing The Video

You can view Drawing Tapered & Splayed Legs by pressing the play icon below or by downloading it to your system.

The video file is mp4. It can be viewed with most video players including QuickTime and Media Player. If you have a default, or user specified, file association for .mp4 you may have to delete it or use a download manager to download this file. Otherwise the associated application may be invoked and file streaming will prevail over downloading. There are numerous free download managers on the internet. Be careful, and do some research to locate one that is not loaded with spyware or viruses.

If you are on a PC platform running Windows OS and have Internet Explorer or Firefox you don’t have to change file association or use a downloader. Simply right click on the link(s) below and choose Save Link As. When Explorer opens choose a destination folder and select Save.

To download Drawing Tapered & Splayed Legs click here or paste

http://blip.tv/file/get/Chiefwoodworker-DrawingTaperedSplayedLegs579.mp4

into your download manager.

Full Screen Viewing

You may find it easier to view the video in full screen mode. Start the video before selecting this mode. To enter full screen mode click the little screen icon at the bottom of the video player. When in full screen view hold your cursor near the bottom of the screen to access the video player’s controls. Exit full screen mode with the Esc key. Sit back, relax and enjoy the show!


A reader wrote me in the comment section of one of my blogs and asked how I like the Performax Pro 22-44 drum sander. He was considering purchasing one and wanted my opinion. I replied “I can’t say enough good things about the Performax Pro 22-44 drum sander”, and I can’t. So much so I thought I would write a post just about this invaluable tool.

This is not a power tool that gets used only on occasion – no sir. Nearly every board in my shop goes through it during at least one process step. Mostly immediately following the planner. I use it for final thicknessing of all parts using 80 grit paper. I may also use it for finish sanding of panels and other parts with 220 grit paper. This is especially true for stock that has grain direction changes that would cause tear out with a hand plane.

Bringing Door Stiles & Rails To Final Thickness My thicknessing process starts with the planner where the stock is brought to within 1/16” or 1/32” of final thickness. If the stock is figured wood such as tiger maple or blistered maple I may even leave the stock 1/8” over sized because tear out on figured woods can be excessive. I will then bring the stock to within 1/32” or 1/64” with the 80 grit paper on the Performax Pro. Depending on other factors, I may even bring it to final thickness with 220 grit drum paper.

The drum sander has five significant advantages over the planner for final thicknessing. First there is negligible to no snipe at the ends. Hence you can save two to four inches on rough stock lengths.

Second, small nicks in a planner or jointer blade leave noticeable ridges in the wood. This only happens on a drum sander if you have a burn in the paper from clogging (generally caused by pitch pockets). But the latter is extremely rare while the former is quite common.

Third, with fine paper you can attain the final thickness while also leaving the stock with a finished surface.

Fourth, you can finish figured woods with no tear out, which is nearly impossible on the planner.

Thicknessing A Wider Than 22" Panel After Glue Up Fifth, and this brings me to another feature of the Performax Pro in particular, is that you can thickness wide panels. The 22-44 in its name means you can sand panels as wide as 22” in single passes, or up to 44” in two passes. Note in the picture on the right that the panel hangs out the edge of the drum sander. Simply turn the panel around to sand the remaining portion.

This can be a little tricky on long and wide panels, for example, 30” wide and 72” long table tops. You must be careful to keep the piece moving and prevent it from drooping over the edge due to its weight. It helps to have a helper in such situations.

A Simple Leg Taper Jig One of the things about a drum sander is that it is relatively safe. You might get pinched if you are not careful but it is very unlikely that you would lose a digit or suffer a significant cut. In fact, if you use your imagination you can use the drum sander to de-risk otherwise risky shop operations. For example, tapering table legs can be a risky operation, particularly on a table saw. But you can taper legs on a drum sander very safely.

In the picture above left I have rough cut tapers on four legs using the band saw in free hand style (this is not a necessary step but one that makes things go quicker). No need to be accurate, just be sure to leave the taper line. Stay an 1/8” away from it if you are not confident about your free hand cutting ability with a band saw; or skip this step all together and do it all on the drum sander.

Tapering Table Legs With A Simple Jig & Drum Sander The jig is simple; use either 3/4” plywood, or as I have here, a Formica covered piece of particle board. Using double sided sticky tape place two pieces of 3/4” wood in the direction perpendicular to travel through the drum sander. Space them for the correct taper by sliding one board closer to or further away from the other until the taper lines are parallel to the jig surface. Place the rough taper legs as I have in the photo with one piece keeping the legs from moving beyond the end of the jig and the other providing the correct taper. You may wish to tape the top ends of the legs together to keep them from slipping sideways. Start with 80 grit paper and finish with 220 grit paper and feed the legs through while monitoring the taper lines. See photo at right above.

Finished Tapered Legs - No Sanding Necessary The finished legs are shown at left; they are completed and require no final sanding. I have found this method to be not only safe, but the final product is more accurate than when cut on the table saw. In addition there are no burn marks from the saw blade which is particularly troublesome with cherry. Lastly, any significant grain direction change is no problem for the drum sander, but might be for even a hand plane. These legs were made for an Office Table which you can read more about by gong to http://www.srww.com/office_table.htm.

Flattening A Panel After Glue Up Glue ups can create wide panels and no matter how careful you are the individual boards do not align perfectly. I generally leave panel stock 1/16” to 1/8” thicker than finished width. After the glue is dried I scrape any excess squeeze out from the panel and then draw numerous parallel lines on each side with carpenter’s crayon. I sand one side keeping an eye on the disappearance of the crayon marks. As soon as they are completely gone I turn the panel over and bring the opposite side to parallel. With 220 grit I then bring the panel to final thickness. See the picture at right.

Two things you need to know about this tool: One, you must have dust collection connected and running at all the times when you are using the Performax; Two, feed the material at half speed, using 1/8 turn on depth adjustment for each pass and don’t let the material stop. I have ruined several pieces of cherry when I first used the Performax Pro until I understood these issues.

One last piece of advice. If you do buy a Performax, it comes with a drive belt that moves the material which is similar to a sandpaper belt. Optionally they sell a rubber surfaced belt. Buy it. It’s worth the extra cost. The grip is better and it doesn’t mar your surface.

As you can see, the Performax Pro 22-44 drum sander is an invaluable and frequently useable tool. Not only does it do a better job in many situations, but it is often more accurate and safer. Its snipe free operation can result in less material used. And it can handle wide boards and panels that the planner cannot. It is the only tool that can handle figured or difficult wood without any chance of tear out. Even my trusty hand planes cannot guarantee that. This machine has been a workhorse in my shop and it is rugged and reliable. I wouldn’t hesitate a second to buy another if I found it necessary to do so. But I have a feeling this one will last so long that buying another will never be an option.


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