Drainage Pipe Clamps





Introduction: Drainage Pipe Clamps

About: I am a professional builder of hollow wood paddle board kits. "The beauty of a Sliver Paddleboard makes it easy to forget you're paddling the most environmentally responsible paddle board on the market."

As a professional builder of hollow wooden paddle boards I have a lot of clamps. One of the handiest clamps I use are these spring clamps made from 4" Schedule 20 perimeter drain pipe. These clamps were originally made for building the rails on my wood paddle board kits, but this summer my wife started stealing them for holding down row-covers in her garden. The clamps do not have crushing clamping force but for their weight they are surprisingly strong. There are many things that make these clamps really awesome:

  • They can clamp at weird angles.
  • They can be used individually with a very light touch or nested together to increase there clamping force.
  • They stay put on narrow edges where other clamps eject themselves
  • They are rust-proof
  • They weigh next to nothing

Probably the coolest thing is they are made from the waste cutoffs that would otherwise end up in the landfill. Every new construction project throws out enough perimeter drainage pipe cutoffs to fill a Rubbermaid with these clamps. It is because of this upcycling benefit that I feel this secrete should not be limited to just wood surfboard builders.

Step 1: Layout Marks

If you are going to make 1.5" clamps you will start by marking your pipe every 1 5/8". 1.5" plus the thickness of your saw blade. If you have already made some clamps you can just slide a completed clamp over the pipe as and use it as a marking tool. (pictured)

Step 2: Pilot Holes

Drill a small pilot hole in the centre of each section. Technically you could skip this step but I usually drill the 5/8" holes with the pipe trapped between my feet so the pilot holes are nice.

Step 3: Drill 5/8" Holes

Enlarge your pilot holes to 5/8". It is best to use a spade bit for this hole. Twist bits drill the pipe so quickly that it tends to grab and torque the bit as you finish the holes. Your wrists will thank-you!

Step 4: Trim the "Bell End"

Drainage pipe has one flared "bell end" allowing it to fit over the next length. If the pipe has a "bell end", it is easiest to cut it off first. You can safely do this by putting something under the pipe and against the fence of your mitre saw as a spacers. This keeps the end of your pipe square.

Step 5: Cut the Clamps to Length..

It is important to slice the pipe into 1.5" lengths before you slice the clamps open. Set-up a stop on the cutoff side of your saw to perfectly space your rings at the desired length. Having them all the exact same length is a nice touch when you nest the clamps later.

Step 6: Open the Clamps

The final step is to slice through the 5/8" hole to open the clamps. I like to use either a Japanese handsaw or a bandsaw for this step. The clamp will want to close on the saw blade as it is cut so be careful if you use a table saw.

Step 7: Safety Tip

A 2x4 fits nicely inside the 4" pipe and keeps your fingers away from the saw blade. This allows you to use the whole length of pipe.

Step 8: Nesting

Schedule 20 clamps are most useful when they are nested together to increase there clamping power. If you are using schedule 40 pipe you probably don't need to nest the clamps. If you are short on clamps in your workshop you will find these clamps very handy. If you have 100's of clamps in your workshop you will see that there are some jobs these clamps out perform the rest. Enjoy!



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31 Discussions

This idea is so handy - clamps can be expensive and although I do not work with wood a lot this idea will help me out in loads of ways.
Thanks for posting, low tech and recycle are my watch words.
Liked this idea so much I have posted it as the FAVE OF THE DAY on F/B group PROTO - TYPE - CHAT, would be great to hear from ya sometime if you had a mo to say something about yourself and your best builds, favorite oldies or the things that inspire you.

Nice job.


The "schedule" is the wall thickness of the pipe. It also is the designation of how much internal pressure the pipe can withstand. Schedule 40 PVC is the "standard" plumbing thickness used for vent and waste lines. Exterior drainage pipe is often schedule 20 (about 1/16" wall thickness or roughly half as thick as schedule 40) because rain water has little to no pressure. Ideally you would use Schedule 40 pipe for these clamps if you are going to buy a length of pipe. I use schedule 20 because the cutoffs from new construction would end up in the landfill otherwise.

What do the different schedule #s mean for the pipes? Great idea, and def less expensive than metal clamps

Great idea. I have seen this before but never tried it. I like the idea of drilling a hole in the pipe to get a curved clamping surface. Schedule 40 pipe would be stiffer than Schedule 20 and might give more clamping force. Thanks for the ideas.

Cool! Silly me, I never considered nesting them for more clamping pressure--could also make some wider (3"?) to increase pressure even more.

Nice Instructable ...please let your next one be about making a Stand-Up Paddle board.

You are a genius!

Thank-you for all the positive comments! I have a few points for readers to remember for some of the other suggestions that have been made.

1. "....If you have issues with it catching and hanging up... go lighter on your feed" - I have made these clamps with twist bits, brad point bits, forester bits and the spade bit is the best choice by far. It is quick and doesn't grab the curved surface as it exits the hole.

2. "....It's not a good idea to trap material between the saw blade and a stop" - I agree 100% with the idea of marking the fence is a safe way to make repeated cuts that don't need to be that accurate. Painters tape is great for marking. I use narrow stops all the time on my mitre saws without problems. You should let the blade stop before raising it past the trapped part. It is important to NEVER do this on a table saw as the trapped stock can become a missile.

3. "...dowel "chopsticks" for opening, an ingenious addition" - It might seem like a good idea but drilling holes in the spine will reduce the clamping pressure and eliminate the nesting ability. I prefer spring clamps for one-handed operations.

while a spafe drill is quick and easy, a twist drill is acurate for size. If you have issues with it catching and hanging up... go lighter on your feed. If you are going with a hand drill... switch to a drill press. And still go lighter on you feed. By feed i mean how hard you feed the bit into the material.


2 years ago

awesome idea. Never thought of It but plan to put this to use asap.

Thankyou or sharing,!


One relatively minor quibble--it's not a good idea to trap material between the saw blade and a stop, unless that material is clamped into place. Otherwise, it can be grabbed by the blade and flung at high speed in some random direction, or splinter and send shards everywhere (ask me how I know). A better way to consistently saw your lengths of pipe would be to use a pen or pencil to mark a tic on the saw's fence up to which you'd slide the end of the pipe for each cut. It's not machinist accurate, but it's plenty close enough for this sort of thing. Great Instructable, though! These "pipe clamps" are so handy!

An addition I saw that might help in some configurations:


1 reply

Love the dowel "chopsticks" for opening, an ingenious addition. Thanks for that.

Great explanation!

Great idea, I'm going to try some for securing bird netting over my vege patches!

I've been carrying around a set of four in my camper. They work great at holding a table cloth on a picnic table.

These look like they would be handy for holding patterns on plywood for tracing, or laying out/marking cuts!

Great to see another clamp solution for gluing rails. Nice.

PatriceL1 - I like the simplicity of your system. Great idea!