Cygnus A

Need help with thread inserts.

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I've been fighting with these inserts and cannot get a grip on how to install them without either stripping the insert or cracking the wood. I first tried using some brass inserts from home Depot. They we're complete garbage and every one of them broke while trying to thread them I to this maple.

Since those did not work, I purchased some EZ Lok inserts along with the tool to install them. These all stripped too. They came with a drill bit that I used on my drill press. The hole is clean and deep enough for the insert.. I such got 1 fully inserted, but it took several inserts stripping to cut the threads completely.

http://imgur.com/a/mSTybBo

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I think I would us an appropriate size and thread pattern, thread tap.  Drill a pilot hole of appropriate size, usually when you pick up the tap it will have a bit or tell you what size to use for your pilot hole,  then tap it with the thread tap.  You can do it by hand with a wrench or you can chuck the thread tap up in your hand drill but go extremely slow so you don't strip it out.  Do a couple of practices in some scrap to get the hang of it.  It works really well for what you are wanting to do.

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I measure the barrel with calipers and drill that size clearance hole.  I cut the head off of a bolt that is the size of the insert.  Double nut it with a washer to prevent jamming.  Chuck the bolt into the drill press and drive the insert in by hand.  You don't have to worry about staying aligned, the DP takes care of that.  Just turn the chuck by hand and lower the quill as if drilling a hole.  If you wood still splits, your clearance hole is too small perhaps.

1541699105_DonkeyEar(3).jpg.cbeffff7bb034aee370c10c6f73cd71b.jpg

Here I am doing it with a cut off hex wrench for smaller inserts used in shop made pulls.  the hex key doesn't thread in and therefor doesn't need the nuts and washer.

Niki CT Dresser (90).jpg

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I agree with the comments above. With a hard wood like maple you will likely have to drill a bigger hole then the bit that comes with the kit.

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I'll toss out one other option, that is perfectly acceptable for connections that aren't expected to be unscrewed often.

Just tap the wood. Most hardwoods will take threads and hold a bolt with no probelm at all. Yes, it is possible to strip the hole. Yes, the threads will wear over time, if used over and over.  But a bolt will hold in wood amazingly well.

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Fractional bits may not give you enough steps to find the right hole size.   I use them on window jambs in very old houses, so the stops can be taken out easily, to remove the sash to be worked on in the future.  Also, in sash with weight cords, I put them in the sides of the sash to attach the cords to, for easy removal without banging on them with a hammer to put tacks into the sash with glass in them.

Nothing is worse than trying to get them into the old Heart Pine jambs, but having a Number set of drill bits allows very small steps to find the right bit.   Most of the time, there is only a very small edge of the threads that actually bite into the wood.

I think the recommended hole sizes for those things must be for White Pine.

You should be able to screw it right in with the dedicated tool.   If the resistance gets to the point where you're having to strain your wrist at all, back it out, and try the next size hole.  On the old Heart Pine, with so much variety in grain size, and the difference between the hardness of the hard, and soft rings, each hole might be different.   With something like Maple, once you find the right size hole, it should work good enough for all of them.

I think I took this picture to try to explain the steps in the process, but decided not to use it anywhere.  I expect you guys here will understand it better than my general audience.  These were 1850 sash, and had a Bunch of nail holes in the sides from being worked on a number of times over their lives.  These were the earliest double hung windows that I've worked on.  On houses older than that, they have all been single hung (where only the lower sash operates, and with no counterweights).

 

CIMG2020.JPG

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8 hours ago, K Cooper said:

Ross, what threads do you refer to? 

I'm talking about using a standard thread tap for the bolt itself, not bothering with an insert. Probably not a great idea for a bolt that is removed and replaced frequently, but as a one-time, or seldom removed fastening method, it works great.

This is where the WW threadtaps that Marc and Andy had going for a while really stood out. Thread taps made for metal are usually too short to properly thread the types of holes one would use in wood. You can always make a tap by sacrificing a bolt of the same size, and grinding a groove or two along its length.

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There are also taps availabile that are called "bottoming taps " These are used to get threads farther down in blind holes. Regular taps have a taper that only works in deep or all the way through holes.  I've also drilled an undersized hole & filled it with epoxy, let that dry then drill the proper sized hole for the tap.  The epoxy hardens soft wood & gives stronger threads. 

Having a complete set of fractional bits, metric bits and "number " bits pays off in the long run by allowing you to find a bit that's just a tiny bit bigger. But it is quite an investment.  Properly sized pilot holes for wood screws just about eliminates splitting.  Having a drill gauge card for the different sets is very handy too.

https://www.harryepstein.com/index.php/1-16-to-1-2-drill-gauge.html

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IMG_3096.thumb.JPG.499e5efd677528fa58b0f3a91000eed0.JPGIMG_3095.thumb.JPG.7a0975dc1823fca1669b5f1a34c794cc.JPG

I had no way out of my house during hurricanes except the garage door. I wanted an exit of a single door. There are 2 more doors to the left that were covered by one large hurricane panel. I covered the glass with 3/8" starboard. I created spacers and attached it with the inserts and bolts. All of the drilling info is on the bag. Without hurricanes the insert bolt holes have a stainless sidewalk bolt to fill the hole. I hope to never use this system. However there will be more hurricanes so I do need to be able to use this system over and over again. The door is a 2 lifetime door.

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I use the type d inserts. If possible, putting them in from behind gives a stronger hold because the bolt will pull it tight. This requires a thu hole.

You can put them into the face with a little epoxy, and they're still plenty strong. 

Typically for a 1/4-20 insert, I use a 3/8 hole. You can buy them with or without the flange. If using the flange, a small countersink keeps it flush.

Insert-Nuts-Type-D.jpg

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