Threaded Inserts ????

[movnup]

I'm finishing up my drill press and router table and am having problems getting the threaded inserts to start / stay in. I'm using Rocklers insert for a 5/16 t-bolt but in using a 3/8 (recomended), 7/16, and also 1/2 guide hole I can't get them to thread in. I also built the jig they had in wood magazine that centers a vertical bolt w/ washer and double nut over the insert then using a ratchet and still no luck. I've also tried different woods - birch ply (the tops), poplar (fences), and oak (hardwood test).

Going down the list I've tried wood titebond, construction adhesive, epoxy, and gorilla glue in the process but none of them stop them from spinning. Such a simple concept but do they even work in birch plywood / do I need a different brand / what am I doing wrong ?????

[Tequila]

If they're the inserts that I think they are, they're meant to be hammered or pressed in. If you're spinning them, then the barbs that are supposed to hold them in place are going to chew up the wood like a rasp, and they won't work.

Does the outside of the insert have a bunch of barbs running along the axis, or does it have a screw thread?

[movnup]

Screw thread ... if you hammered them in why would you have a screw thread / screw w/ barbs on the thread / screwdriver slot on both versions on the top of them ????

I sure would love to take a hammer to them that's for sure

From Rockler's website:


Made from steel. Size listed is the size of the internal machine threads.
Sold in pack of 8.

Can be installed with screwdriver, threaded insert wrench or threaded insert power drive tool.

[bradley_osu]

I installed those into my workbench (MDF) using the method described in Workbench magazine. They drilled a slightly oversize hole, the threads of the insert should barely dig in (my inserts just set in without any screwing). Put masking tape on the bottom of the insert and put epoxy in the hole. Screw a small bolt and fender washer into the threaded insert and drive it in with the bolt. The washer keeps it flush with the table surface and the epoxy does the real holding. It works like a charm for my miter saw fence.

I'll see if I have that article lying around and can scan it for you.

If the hole is tite and you screw those inserts in you sometimes get buckling in the wood around it which isn't nice, you also run into the problem of there not being enough surface area for the epoxy to hold onto.

[bmyers]

There was a wood-mag somewhere (shopnotes?) that suggested putting a bolt in your drill press and double nutting the insert onto that bolt. Then twist the insert into the wood by turn the drill manually and press slightly with downward motion of the press.

That way it goes in straight and you have some grip behind it.

HTH,
Bill

[Pappy]

I've used the brass inserts that Lowe's sells on several projects. Always into solid stock, not plywood. I play with some scrap with different size holes until I find one that threads in good. I also slightly chamfer the edge of the hole so the initial bite is in the wood a little.

With the courseness and depth of the threads, I would think they would pull hard enough on the plywood to tear through the laminations before they could get a good bite.

[cgallery]

Can you switch to the style Joe was referring to (with barbs)?

Seen here:
http://www.rockler.com/product.cfm?p...eaded%20insert

I've used 'em in plywood and they hold great. You can apply epoxy to the hole before you knock 'em in, if you feel that is necessary. I never found it to be.

If I was really concerned about strength, I'd use a barbed insert, and counter-sink the hole for the flange. Then I'd epoxy it and bang it in.

[movnup]

The Wood Magazine jig I built mimics Shop Notes drill press idea with the double nut and the bolt w/ washer threading it in. I called Rockler and he thought the barbed version banging it in and with the popular wood fences the ones i had were supposed to work !!! I'm going over to Rockler after work and try the barbed version with epoxy as that sounds like the ticket for ply.

I'm also going to try chamfering the edges first as mentioned above and that I saw in a Woodcraft article. Great feedback everyone !!!

Can anyone recomend a brand / type of epoxy they like as the HD version I used didn't hold ???

[Popeye]

Can anyone recomend a brand / type of epoxy they like as the HD version I used didn't hold ???

I use 5 minute epoxy. HD/Lowes and auto parts stores all carry it. Pat

[JimD]

I have had good success with harbour freight 5 minute epoxy. I was pleasantly surprised.

I have also used a lot of screw in inserts like these. I cannot quite picture your application but when the hole depth permits, I find it handy to have an inch or more of bolt going through the insert. That gets me well aligned before screwing the insert into the hole. When I want to be extra sure it does not split the wood or bulge it out, I drill an oversized hole and use the epoxy to hold the insert. I have used #8 threaded inserts up to 3/8 inch and they all work. I've put them in particle board, MDF, oak, and pine. Maybe some others I am forgetting. Larger holes for hardwood but otherwise they seem to work well.

I do not like the hammer in variety. The ones I used are made of zinc which is soft and less durable than brass or steel which is what is generally used in the screw in variety. I've had the inserts pull out and also had the machine threads pull out of the inserts. I haven't had either problem with the screw in type.

Jim

[scorrpio]

I recently did a project that needed to be easily assembled/disassembled, so it used a LOT of 3/8" threaded inserts. I took a bolt, cut off its head, and threaded two nuts with a lock washer between them. About 1/2" of bolt protruding below the nuts. Then, I chucked this contraption into a regular hand drill and put a bit of oil on the bolt and lower nut.

The insert is threaded onto the bolt till it is against the lower nut, then you hold the drill as close to a right angle as you can get, and put the insert in. Use low speed - about 1-2 rotations per second. On my Dewalt, I was just barely pressing the switch.
Once the insert is all the way in, switch into reverse, and give the trigger a good squeeze. The fast speed and oil should disengage the bolt from the insert, leaving it in place. It took me less than a minute per insert this way. There were a couple of stubborn ones that caught and would try to come out along with bolt - for those, I'd unchuck the bolt, and use one wrench to hold lower nut while I loosened the upper one, and then holding the bold with vise-grip while I losoened the lower nut from the insert.
Aside from those few, I got 50+ inserts perfectly seated with no fuss in less than an hour.

[movnup]

In response, the applications are bolting my drill press table top to the drill press original metal table (four 5/16 x 1 bolts coming up from underneath), the back side of left / right sliding router fences, and custom vertical material hold down clamps for the table. I went to Rockler and the guy there wasn't much help and he said "I never have a problem I don't know why you do .... buy my $11 insert bit " !!! I bought the barbed inserts and they had some cheapie epoxy but the barbed inserts are 3/4 inch and the stock I'm using is also 3/4. I'll cut them down and see how it goes ...

Now that I'm frustrated at Rockler talent / parts what other sources besides Lowes that Pappy mentioned do you get the brass / steel inserts that worked well and right the first time for you all ?????

[LarryG]

Now that I'm frustrated at Rockler talent / parts what other sources besides Lowes that Pappy mentioned do you get the brass / steel inserts that worked well and right the first time for you all ?????

Without looking I don't know whether either will have exactly what you need, but I buy most jig and fixture hardware from either Lee Valley or Woodpeckers -- the latter when possible, as they tend to have more reasonable prices on this sort of stuff than most vendors.

[cabinetman]

I use the threaded inserts, not the barbed ones. The trick to these little buggers is to drill the correct size hole the correct depth, clean it from debris, and make sure it is straight (90 deg to the panel). Then turn in the insert. They work best being inserted once and are much better than the barbed ones.
.

[JimD]

I also like Lee Valley for hardware and also Hartville tool. I think it is Hartville that has little 8x32 inserts if you ever need those. Lee Valley's smallest is 1/4 inch, if I remember right. Hartville's are brass plated steel and I think Lee Valley's are brass.

Jim