Stripped Knobs and Pulls

It is not fun to deal with knobs and pulls with stripped threads so that the knob or pull come off of the drawer or door when grasped, yet it happens frequently. 

Many at Instructables have dealt with this often in their time. This is for the person who has the problem, but does not know what to do about it.

Step 1: The Problem and One Solution

The threads strip out in the first 1/8 inch or so of the threaded post on the backside of the knob or pull. Many simply insert part of a paper matchstick into the hole and twist it back onto the screw. This may last for a very short time, but eventually fails. 

Step 2: The Real Solution

The entire length of the post on drawer hardware is threaded. Push a toothpick into the hole and pinch it with your fingernail to indicate the length of the threaded portion inside the post. The distance from where your fingernail pinches the toothpick to the end of the toothpick is the ideal amount of threads to extend beyond the finished surface of the cabinet wood. You really want to shorten this distance by about a millimeter or two in order to allow a little free space for tightening the knob on the screw. Add to the amount of thread extending beyond the finished wood surface the thickness of the cabinet door or the drawer front. You may also need to add the thickness of a washer. See the next step.  

Step 3: Small Head?

The screwhead on the left is the screw removed from the knob or pull. The screw on the right is a standard screw from the hardware store. Notice that its head is smaller than the original screw. Adding a washer gives it better support against the wood on the back side of the door or drawer front and is a good idea, but it also adds a little thickness that needs to be considered in preparing a screw for your knob or pull.

Step 4: A Handy Tool Worth Having

The photo shows a wire stripper tool for household electrical work. These are available in many tool departments, particularly in the electrical tools at a big box store. They are not expensive to buy. 

Although useful for stripping wire sizes commonly used in homes and for pinching crimp connectors, this one also has five holes on each side of the tool for cutting screws of different common sizes without damaging their threads. The screws for cabinet hardware are 8-32 in thread size (#8 diameter screw, 32 threads per inch). 

Step 5: Insert the Screw From the Proper Side

You will not likely be able to buy a screw the exact length you need. Buy a screw that is a bit longer than you need and plan to cut it. Twist the screw into the proper hole on the threaded side of the tool. That would be the side with the threads, not the side that has smooth holes. Notice that there is even an instruction to the user that says, "Insert screw here." 

If you were to insert the screw from the other side, the threads would be damaged in cutting the screw to length. 

Step 6: Cutting the New Screw to Length

Twist the screw into the tool so the screw will be cut at the proper length. This is indicated by the yellow arrow. Try to be as accurate with this as possible. If anything goes wrong, you can always buy another screw and try again, though. When you are ready, firmly squeeze the handles on the tool and the screw will be pinched off. Turning the screw back out of the tool will make the threads at the end of the freshly cut screw as factory new as possible. 

Step 7: The Results

On the left you see an original cabinet hardware screw. On the right you see a freshly cut replacement screw. It is just enough longer to catch fresh threads in the stripped cabinet knob or pull. See also the second photo, which shows the original screw in the cabinet door; and the third photo, which shows the new freshly cut replacement screw. Some of the old stripped threads are only partially stripped and will add some additional gripping power. 

You will have saved your knob or pull, which may no longer be available new in the pattern you have on the rest of your cabinets. Cutting a new, longer screw can get you out of a difficult situation. 

If your knob is still too loose after cutting to length, you could add extra washers to the head to take up the extra and make it tight. If the screw does not grab enough threads after cutting, you could drill out the back of the door or the drawer front using about a 1/2 inch bit to gain some length. But, both of these are "desperate measures" for getting out of a special, very difficult problem.

Comments

[BarbB58]

I'm putting a fan together and the fastening knob is stripped; I can't screw it in or back out what do I di

[Phil B]

Despite the photo, I am having some difficulty visualizing exactly what you have, so I will offer some general things. Can you get a thin screwdriver or a butter knife between the knob and the surface below it? If so, apply a bit of pressure in the direction for removing the knob and hold that while you turn the knob in the normal direction for removing it. That may help you get it off. Are the threads on the shaft that holds the knob metal? Can you find or buy a replacement knob to screw back on? Or, can you slip a shim inside the hole in the knob that will tighten up the threads? Sometimes people put some JB Weld (epoxy) on the threads and push the cap back on. That works, but creates problems for the next person.

[steptoe49]

I was looking for the thread type for the drawer nut as I had to tap custom handles and found it here. Thanks Allan Townsville

[Phil B]

Glad to have been of help. Thank you for looking.

[mole1]

Thank You!! I'm not living alone, but we've had two of those electrical tools around forever ... and had no clue those holes were screw cutters.

[Phil B]

Not only do they cut screws, but they preserve the threads pretty much undamaged on the portion you want to use. Thank you for looking and for commenting.

[pfred2]

If you don't have that tool to cut screws there is a trick to cutting threads with a hack saw where you pull up on the unsupported end right before you cut through and threads come out so you can use them. In my workshop I usually cut threads straight off, chamfer on a grinder, then wire wheel them myself. But that method does require the most equipment.

I've filled stripped holes with JB Weldit and then redrilled and retapped them. Of course the simplest method is just throw some epoxy in there, put it together and wait for it to dry, but that has its drawbacks if you ever want to disassemble hardware. I've also filled holes with braze, or even weld then done the whole drill tap routine on it. Depends on the situation, what I'm looking for etc. Also I've drilled out plenty then retapped it to the next size up. That is always my first choice for dealing with stripped out stuff because to me it is the best, and easiest fix. But it often isn't an option for a variety of reasons.

I've done as you suggest here and still had blow outs. Some hardware is under sized, and some materials are inferior and having the top stripped out already is just another strike against you sometimes.

[Phil B]

Thank you for the information on alternatives. So far I have never had stripped threads in the knobs or pulls when I used longer screws. Filling with braze or welding could be possible if one can be certain the melting point of the cabinet hardware is not too low. When I did this, I envisioned the woman who lives alone and may not know about the screw cutting section on a wire stripper. She is in a better position to help herself than she may know.

[pfred2]

Those aren't alternatives for stripped pulls necessarily just other stripped things. Ever tried just wrapping the screw with some thin wire and threading it back in? Sort of like a homemade Heli-Coil.

[Steliart - Stelios LA Stavrinides]

Only you Phil would have thought an Inbl like this, very well done as always.
Thank you for sharing

[Phil B]

Thanks, Steli. It seemed to me this is a common problem. The fix is probably obvious to many. But, there may be some, especially younger people out on their own for the first time, who would not think of how to solve the problem, other than bubble gum or cellophane tape. Thanks for looking. I hope all is well with you.