AKA The Dog Bed Chronicles: Part 2.
You may recall that two weeks ago, I wrote a post about making a box cushion for my dog, Freddie, who has recently become a picky sleeper. This is the continuation of that project: a tent for the cushion.
This project began with a sketch and a paper model and ended with me sitting on the floor, drinking and swearing at plastic zip ties while I stitched them into place by hand. Mistakes were made.
The good news is that I was able to figure out how to jerry-rig a solution after "finishing" the project and can guide you, dear reader, to the correct design from the get-go.
We'll begin with an overview of the project and details of my mistakes and how to avoid them, then move into the design and production parts of the project. Click here to skip ahead to the design, which includes the corrections for my errors.
Note: This post is a bit longer than my usual - now is a good time to grab your favorite beverage.
Q: What materials do I need to make this project?
A: You will need:
Fabric - see the end of the design section for suggestions on fabric choice, cutting layout, and yardage calculations.
Matching thread
Bias tape, garment tape, or extra fabric to make boning channels
See my post on Making Bias Tape Quickly to make your own!
Some kind of boning - I used plumber's zip ties which are available in any hardware store. You can use any sort of semi-rigid boning or similar. Wire, like that used in coat hangers, would also work.
Matching thread
Straight pins
Fabric scissors
Pinking shears are great if you have them
A rotary cutter and cutting mat may also be helpful
Scissors or tin snips to cut the boning - don't use your fabric scissors for this!
Sand paper - if needed to file down the ends of the boning pieces
Electrical or masking tape - may be needed if using zip ties for boning
Tailor's chalk / a pencil / something to mark the fabric
An appropriate sewing machine needle for the fabric used (e.g. jeans needle for working with denim)
Zipper foot for the sewing machine (not absolutely necessary but helpful)
A box cushion - see the previous post here on how to make one
Project Overview & Learnings
The basic idea behind the dog bed seemed very simple: a half cylinder supported by boning channels (zip ties) with a rounded door in the front. I started off playing with several, more traditionally-shaped tent designs, but decided this one would be the easiest to sew and have the easiest pattern to draft. This was mistake number 1 but we're sticking with it.
See the problem is that plastic zip ties are pretty good at adding stiffness to a seam (I've used them for inexpensive corsetry before), but they're not good at supporting a lot of weight. Exhibit A: The "completed" project.
In retrospect, this design might have worked if I hadn't used such a heavy fabric (denim). Quilter's cotton or even a lightweight synthetic might have been a better option. Had I used a higher quality boning (read: not plastic zip ties from the hardware store), it also might have worked. Alas, I used denim and zip ties and the whole thing collapsed.
The "obvious" solution was to double up on the boning. This was actually quite difficult because I'd made the channels as snug as possible to hold the zip ties in place. But I persevered and proceeded to shove an extra zip tie into each boning channel. This took over an hour and rubbed my fingertips raw. Guess what? Not enough to hold up the tent. At this point, Fred and I went for a walk to calm down.
Next up was adding more boning channels that went down the center of the tent. It was too late to machine stitch on any more channels, so I used some garment tape and hand stitched some extra connection points down the center of the tent. After threading two zip ties into these channels, I found it helped a lot with the structure! But the baby channels were spaced so far apart that the fabric was gapping pretty badly between them.
At this point, I was (a) drunk and (b) frustrated so I said some swear words at the fabric and started directly lashing the zip ties onto the fabric by hand. This helped a lot and did me the super fun favor of highlighting that I had originally stitched in multiple mistakes. Eh.
If one extra set of boning helped, more must be better! I then proceeded to lash two more zip ties each halfway between the new center channel and the ends of the tent. While it's not pretty, it holds itself up and that's what matters.
Some Learnings
(Thought 1) Denim was probably not the best fabric choice for the tent. It made a lot of sense for the cushion because of its durability (and Fred's tendency to dig), but was overall too heavy for the tent. Were I to do this again, I would definitely choose something lighter but still durable. Perhaps a cotton-poly blend in a dark color to give it that cave-like feel dogs seem to love so much.
(Thought 2) Wider boning channels definitely should have been used. They would have been easier to make, but also far easier for the actual zip tie insertion stage. And my fingers wouldn't hurt so much after needing to double up.
(Thought 3) In the jerry-rigging stage, there was absolutely no need for those baby garment tape channels. I should have stitched little pockets at the ends of where the boning needed to be (preventing it from scraping the floor) and then just lashed the zip ties down all the way to the other side. This would have been quicker, more uniform, and honestly more effective.
(Thought 4) Definitely could have left a few inches of fabric across the bottom of the door. I seem to have forgotten the cushion while planning that bit out. This change would have made the bias tape around the opening easier and definitely would have made attaching the bottom to the long piece easier as well. The door definitely doesn't need to be so wide either.
(Thought 5) Freddie does not care for my struggles.
Designing the Dog Tent
This dog tent went through several iterations on paper and a final iteration via failure during production (see above). The version presented here should hold itself upright with no visible boning. Two comprehensive diagrams are presented: one with dimensions and one with boning channel layouts. Calculations for the dimensions diagram are shown step-by-step, beginning and ending in the comprehensive layout.
It looks trickier than it is and we're going to walk finding the correct measurements step-by-step.
As always, let's start with some math! As we go through this, if your measurements are different from mine, be sure to draw your own diagrams with labels so you can reference them later.
(Step 1) Measure the final size of your dog tent.
Width and length will be determined by your cushion size. My measurements are shown below - be sure you have all the measurements before starting in on the math so you don't have to make changes later!
Width = w = 24 inches
Length = L = 36 inches
Height = H = 18 inches (as measured from the cushion to the ceiling)
Cushion height = h = 3 inches
Door width = 12 inches
Door height = 16 inches
Width of boning (I used zip ties) = 3/8ths inch
Seam allowance = s = 1/2 inch
(Step 2) Calculate the dimensions for the bottom piece.
The bottom is the simplest so let's start there. Calculate the length by taking the length of your tent and adding twice the seam allowance:
length = L + 2s
For me, that means I'm adding 1 inch to my length of 36 inches, so I get a total length of 37 inches (shown on diagram).
Repeat using the same math for the width:
width = w + 2s
Again, that means I'm adding 1 inch to the width. So 24 + 1 = 25 inches.
While we're here, we may as well calculate the diagonal which we'll need later for the boning channel math. You can use the Pythagorean theorem to do this:
(Step 3) Calculate the dimensions of the end pieces.
Time to get fancy because the end pieces have two shapes - a semicircle and a rectangle. But don't be intimidated, the arithmetic here is simpler than it seems.
First, we already know the width of the end piece as we just found it in step 2 (for me, 25 inches). To find the height, we need to account for both the cushion and the seam allowance:
height = H + cushion height + 2s
For my project, that means 18 inches plus 3 inches plus 1 inch total, so 22 inches.
Next, we'll find the radius of the circle aka the top of the end piece. To do this, take the width and divide by two. That's it!
radius = r = width / 2
For my project, that's 25 / 2 = 12.5 inches. This will be helpful later when trying to draw the semicircle on the fabric before cutting.
To find the height of the lower bit of the end piece, aka the rectangle, take the height we just found and subtract the radius.
rectangle height = height - r
For my project, that's 22 - 12.5 = 9.5 inches. Done!
(Step 4) Calculate the size of the side piece.
This piece is the trickiest because we have a rectangle AND the door. Good news is we've just done similar types of math above so this shouldn't be much more difficult.
First, the rectangle. We already found the length of the rectangle in step 1 (for my project, 37 inches).
Next, we need to find what I'm calling the long length - this is the measure that will wrap up and over the end pieces. This is the most complicated our math for this project will get. We just need a little bit of circle geometry to get it done.
What we need to do is find the perimeter of the sides and top of our end piece. The end piece diagram is shown again below, for reference.
To do this, we'll take the rectangle height (9.5 in on diagram) plus the perimeter around the semicircle plus the rectangle height again. We don't want the full perimeter of the shape because the bottom piece will be separate (we did the bottom piece in step 2).
Since we already know the rectangle height, we just need to determine the perimeter of the semicircle which I will label P in the equation below. To do this, we use the formula for the circumference of a circle, but divide by two because we only have half of a circle:
P = circumference / 2
P = 2πr / 2
P = πr
P = (3.14)(12.5)
P = 39.25 inches
Now we just add the rectangle height twice to get our final measure:
long length = rectangle height + P + rectangle height
long length = 9.5 + 39.25 + 9.5
long length = 58.25 inches --> round down to 58 inches
Woo! Hard part over! Now we get to figure out the door. Nice thing about the door: we'll use bias tape to bind the opening, so we don't have to include seam allowance in the door size calculations. Smaller crop of the diagram above included here for reference.
First, let's get the placement out of the way. Take the height of your cushion and add the seam allowance. Bingo, this is the distance from the bottom edge and side edge where you'll cut the door hole. For me, that was 3 inches + 1/2 inch = 3.5 inches.
Now the fun stuff! Take the door width and divide by 2 to get the radius for the top part of the door.
radius = r = door width / 2
For me, that's 12 inches over 2 = 6 inches.
To find the height of the lower part of the door, aka the rectangle, take the door height and subtract the radius.
rectangle door height = door height - r
For my project, that's 16 - 6 = 10 inches. Done!
Be sure to record these dimensions on your own diagram to make the cutting process easier. For reference, here is my complete diagram:
(Step 5) Figure out boning channel placement.
See the diagram below where each dot-dash line represents a boning channel:
Importantly, you'll see that the end pieces have no boning channels. This is because boning will not bend sideways, only forwards and backwards. So to get it to lay flat, that means it has to be on the side piece, not the ends.
The rest of the boning channel placements is as follows:
Bottom piece - 6 channels total:
One channel along each of the four sides (4 channels)
One channel along each diagonal (2 channels)
Side piece - 9 channels total:
Along the long length, 5 channels total: Two on each of the long lengths, one down the center, one between the center and the long length, one between the center and the other long length.
Since this piece will measure 36 inches without the seam allowance, that means there will be about 9 inches between each of the channels.
Along the regular length, 4 channels total: One in the center, one between the center and the door, two between the center and the end.
To be honest, I didn't do the math here I just guessed it would be about 10 inches between the channels. You can also just eyeball it, it's really not noticeable if these are off a bit.
There are a lot of channels on the side piece and you will spend a lot of time sewing them down. It's worth it though, as the boning will hold the tent up and the channels will hide the boning while also helping to keep it in place.
(Step 6) Calculate the fabric needed for boning channels.
Here's where that measurement you took at the beginning for the width of the boning comes in handy. Take that measurement and decide how wide the channels need to be. In my original project, I used 3/8 inch zip ties and 1/2 inch channels. In retrospect, that was not wide enough. If you use the zip ties, I recommend using a width of 3/4 inch. If you will purchase bias tape instead of cutting channels out of fabric, this is the width to look for on the packaging. If you will purchase bias tape, single fold bias tape is the way to go for boning channels.
Take that width and multiply by 2 to get the width you will cut out of your fabric. For 3/4 inch wide channels, that's 6/4 inch = 1.5 inches wide. Below, I refer to this as the strip width.
Now we find the lengths:
Cut 6 pieces of the strip width by the length of the bed (2 for the bottom piece and 4 for the side). For my measurements, this is 1.5 inches x 37 inches. Just to be safe, I like to add a little extra at the ends, so I cut 6 pieces measuring 1.5 inches x 38 inches.
Cut 2 pieces of the strip width by the width of the bed - these will be for the bottom piece. For my measurements with a little wiggle room at the end, this is 1.5 inches x 28 inches.
Cut 2 pieces of the strip width by the diagonal length - these are also for the bottom piece. For my measurements with a little wiggle room at the end, this is 1.5 inches x 46 inches.
Remember to add these pieces to your cut list for later!
(Step 7) Calculate the fabric needed for bias tape.
Bias tape can either be easily made for this project or purchased separately.
The only place you need bias tape instead of channels cut along the grain is to finish the edge of the door. To be honest, I cut the door out and measured. If you're buying bias tape separately, you might just buy a package of tape, but you could also do the math which would make the most sense if you're also using purchased bias tape for the boning channels.
In this case, to find the total amount to purchase, add all the lengths of the channels together, then add to the perimeter of the door. To find the perimeter of the door, we'll do the same math we did to find the long length above.
To find the perimeter of the door (labeled p in the equation below), we'll find the circumference of the circle and divide by two (because semicircle), add it to the rectangle heights on both sides, then add it to the width of the door:
p = (circumference / 2) + 2(rectangle height) + door width
p = (2πr / 2) + 2(rectangle height) + door width
p = πr + 2(rectangle height) + door width
p = (3.14*6) + (2*10) + 12
p = 18.84 + 20 + 12
p = 50.84 inches --> round up to 51 inches
I recommend adding a little to that measurement just for safety. In this case, I'd use around 55 inches for my purchasing measurement. Purchase double fold bias tape the door (or purchase single fold for the boning channels and just plan to iron in an extra fold to go around the door).
If you will make your own bias tape, first decide how wide you'd like it to be. I went with 1/2 inch tape which was 1/4 inch after the fold. This was a bit fiddly so I'd recommend starting with 1 inch wide tape. To cut the tape, remember to double that number to 2 inches! To make the bias tape, check out the tutorial I wrote here.
(Step 8) Finalize the cutting diagram and purchase materials.
At this point, you should have all the measurements you need for your pieces. After choosing your fabric, take a look at its width to help you figure out how much you'll need to purchase based on the size of your pieces. Remember that you can always cut the boning channels and bias tape out of a contrasting fabric, it doesn't have to match.
Q: What fabric is best for this project?
A: For my project, I used denim to match the cushion I already finished. However, I found it was a bit heavy and the zip ties struggled to support its weight. I would recommend a lighter fabric, like a cotton or poly blend. You could use a fabric with a little bit of stretch, but I would recommend a one-way stretch (cut so that the stretch goes along the curve) and no more than a 10-25% stretch. This is a great opportunity to stash bust too, if you're up to piecing some bits together.
Putting it Together
Take a breath, the math is behind you! Time to get to the fun stuff - remember to wash and press your fabric first!
(Step 1) Cut out all pieces.
Use your diagrams from the design process to cut out all the pieces for the project. You should have:
1 side piece with door
1 bottom piece
2 end pieces
Boning channels:
5 pieces the long length by the strip width
6 pieces the length by the strip width
2 pieces the diagonal length by the strip width
Note that the image here cutting out the door is from my original design, NOT the design shown above in the instructions. It should be fully cut-out from the fabric but not touch any of the edges. This will make the sewing process a little easier and also look nicer for the final product.
Once everything is cut out, take this opportunity to press your fabric one last time.
(Step 2) Press all the boning channels and bias tape.
Ironing is just the best /sarcasm. Time to get real friendly with your iron and press the boning channels so that the edges meet at the center of the strip.
You can use a bias tape maker if you have one, or use straight pins as in my bias tape post to help speed up this process.
Press your bias tape as well. The bias tape will need an additional pressing to be double fold tape. That is, after pressing the edges so they meet in the center, fold the tape in half and press again.
Machine check: make sure the needle on your machine is appropriate for the fabric you've chosen for this project (e.g. jeans needle for denim)!
(Step 3) Finish the door edge with bias tape.
Beginning on the wrong side of the fabric, stitch one side of the bias tape to the door opening, working close to the edge of the bias tape. Note that my photo shows the old style door, yours will not begin at an edge. I recommend starting somewhere along the bottom of the door opening.
Work your way around, easing the tape along the curve. You can, of course, pin the tape in place before stitching. I did not because I did not.
When you meet the end where you began, overlap for an inch or so, then tuck the end of the tape under so no raw edges are left exposed.
Fold the bias tape over to the right side of the fabric and stitch, keeping the needle close to the edge of the tape.
The door opening should now be completely bound so it won't fray, with no raw bias tape edges showing.
Check your work and make any repairs as needed where the needle strayed (confession: I always have to fix at least one spot).
Iron the door opening to finish this step. This will help control and correct any wrinkles or waves that happened from stitching the edging.
Note: If using a fabric that likes to fray, now is a good time to baste around the edges of the bottom and side pieces. They will be handled a lot while attaching the boning channels but before the seams are done.
(Step 4) Mark all boning channel locations on the bottom and side pieces.
I found it easier to start with the bottom piece, then move on to the side.
Use your diagrams to guide the placement for the boning channels and mark them using chalk/pencil/whatever on the right sides of the fabric. Keep in mind that you don't actually want to mark the centers, you want to mark one edge. This is the guide you'll use to stitch the channels on in a minute.
To mark the edge instead of the center, first make small marks where the channel centers will be, then measure half of the channel width to one side and draw across from there. You can see in the image of marking the side channels that I realized this after drawing a few - the center is shown in blue and the correct, edge marking in yellow.
For the diagonal lines, I found it easiest to use the fabric channel to help mark them as my straight edge wasn't long enough.
(Step 5) Stitch on the horizontal boning channels.
Stitching the boning channels is the most time-consuming step- I ended up doing this over the course of a few days. Shout out to the Stormlight Archive book 4 (Rhythm of War) audiobook for keeping me sane.
To stitch on each horizontal boning channel:
First, line up one of the edge folds with the line you marked in the previous step. Fold over a little bit of the channel so that the raw edge will be tucked under when finished.
Stitch along the fold, making sure it follows the line you marked in the previous step.
When you reach the end of the strip, leave about 1/2 inch of fabric and cut off any excess (remember we left some in for wiggle room earlier).
Fold up the remaining 1/2 inch to keep the raw edge from being exposed, then continue stitching to the end.
Flip the strip over to create the channel and stitch as close to the edge as possible. I use the inside of my presser foot as a guide - it's basically top stitching along the channel.
When you reach the end, remember to turn and go across the end of the channel so the boning won't poke out one side.
A note on this: I found it helpful to have the boning channels all open in one corner of the bottom piece and on one end of the side piece. It doesn't really matter, but something to think about in your planning.
Put aside the side piece for now, we'll finish up the bottom and double back.
(Step 6) Stitch the vertical boning channels to the bottom piece.
The steps to actually attach the channels are exactly the same as above, but the vertical channels will butt up against the ones you just finished.
To deal with them, you will not overlap these channels, just begin and end immediately next to the horizontal ones you just finished stitching. Remember to only close one end!
(Step 7) Stitch on the diagonal boning channels to the bottom piece.
Here, follow the same steps to stitch down each of the channels diagonally, making the ends of the channel butt up against the horizontal and vertical channels already stitched down, but not overlapping.
The tricky bit is sewing on the second of the diagonal channels.
Stitch it exactly the same as all of the other channels, BUT, be sure to "jump" the seam over the other diagonal channel. That is, stop the seam (backstitch), pick up the foot, and restart the seam on the other side of the already-stitched channel.
When finished at the machine, you should be able to slide something between the two channels. This is exactly what you want (otherwise the one boning channel would be cut off).
Finish the top channel by hand stitching it to the channel below, making sure to only catch the channel fabric on top and none of the folded edges hiding underneath. This will keep the edges from fraying and the boning in place once it's added in.
(Step 8) Stitch the vertical channels on the side piece.
The method here will be similar to stitching the diagonals above in that you need to "jump" over the horizonal channels which have already been stitched down.
Stitch the channels as before. Remember that one side of the horizontal channels is closed already, so it's safe to stitch right next to that end. For the end that needs to remain open, you'll have to "jump" on both the initial stitch down AND the stitching after folding the channel over to topstitch.
Hand stitch in place as before to finish the channels.
At this point, all of the boning channels should be completed - if you were going to reward yourself for finishing this part now is the time! Personally, I went with a whiskey sour.
(Step 9) Sew the side piece to the bottom.
Pin one of the length edges of the side to the bottom piece, right sides facing. That is, match up one of the short sides of the side piece to the long side of the bottom piece, right sides facing. I found it easiest to first find the centers of the edges of each piece, then match them up and pin in either direction.
Sew, being careful not to stitch into the boning channels. I used a zipper foot for this.
Repeat with the other end of the side and bottom pieces.
You should have a rather large tube when finished.
(Step 10) Sew on the ends.
Pin one of the end pieces to the end of what is now a tube, right sides facing. I used a lot of pins around the curved edges to help keep everything in place.
To turn the sharp corners, you can snip into the end piece's seam allowance at the corner. This should help provide a nice, crisp turn at the corner.
Stitch, being careful not to go into the boning channels. Again, I used a zipper foot here.
Repeat with the other end. Yes, this will "close the tube," but remember there's a door.
(Step 11) Trim the seams and turn right side out.
I like to use pinking shears to trim my seams because it helps with the fraying issues later. If you don't have pinking shears, regular scissors will do just fine.
Trim all the seams, then use the door to turn the whole thing right side out.
(Step 12) Add the boning.
For boning, I used plumbing zip ties. These XL zip ties are plastic and have one end that's a bit tapered and another end with a zip tie head (I don't know what to call it but it's that bit where you put the rest of the zip tie in and pull tight).
To fit my zip ties into the boning channels, I take one at a time, slide it into the channel, then cut off the head.
I then use sand paper to file down the cut end. This isn't a 100% necessary step, but it prevents my hands and the fabric from getting cut. It also keeps the ends from scratching the floor or other furniture later.
Some of the boning channels are really long and require more length than a single zip tie. In this case, I take two pieces, butt them up against each other end to end, and tape them together.
I like electrical tape because it's smooth and slides through the channels easily, but any strong tape will work.
I found it easiest to do all the bottom channels first, then the horizontal channels, then the vertical channels.
As you add the boning to the channels, now is an excellent time to develop your Dr. Frankenstein impression: ARISE!!!
Final Thoughts
You made it! Even if all you did was read through the post, I appreciate that as this has been a long one.
This project was fraught with mishaps, mistakes, and occasional regrets, but the final product has come out looking pretty OK. More importantly, it's functional. I hope your projects come out just a little bit better than mine (remember the tutorial above includes corrections to avoid my mistakes).
I'd love to see your projects, whether in progress or complete - tag me on Instagram @Craftematics, like the post, leave a comment, and be sure to subscribe to the blog using the form at the bottom of the page so you never miss a post!
