Budget Time-sert kit


Oh the usual... I bowl, I drive around...
If you've ever priced out a Time-sert kit you may have balked at the price; $80+ for most, with every size and pitch requiring a new kit. If you already have a tap set, this is a cheap alternative.
If you don't have a counterbore set, you will need to buy one. They can be had for as cheap as $37 on amazon and can be used for your other projects as well.

Step one, buy and measure your Time-serts. Typically the OD of the insert is 2 sizes up from the screw size, with the same pitch. For example a M10 x 1.25 bolt will use an insert with an OD of M12 x 1.25

Step two, drill the hole for the correct tap size

step three. counter bore the hole approximately 1 mm, you will want the counter bore to be as close to the diameter of the lip on the insert as possible, this will mean using a counter bore with a pilot smaller than your hole. wrap some masking tape around the pilot on the counter bore to help the bit self center in the hole, oil the outside of the tape after. You are removing very little material here so the tape should last long enough for one or two holes.

step 4 tap the hole.

step 5 file four sides of a bolt thread flat, it is the same size of the insert ID. Take just enough off to take the thread down to the minor diameter of the threads. this is your insert driver.

step 6. make sure the tapped hole is clean and dry, thread the insert into the hole. Oil the driver and thread it into the insert all the way through the opening, thus expanding the insert and making it permanent.

Thats it, you're done! It works great, i just did several inserts this way but forgot to take pictures during the process. here is a pic of the "driver" with 4 flatted sides. and a pic of the counter bore set I used.


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I thought you needed special STP taps for time serts. Could I use this for say a m5 x 0.8mm ID time sert? https://www.harborfreight.com/hand-tools/tap-die/40-pc-carbon-steel-metric-tap-and-die-set-62832.html
I'm not sure. I would buy the inserts first to confirm the OD and thread size before doing anything. Its probably m7x.08 which is a very unusual tap size and won't come in a tap kit. I would say its probably more cost effective for this to buy the time-sert kit for this size, particularly if you don't already have a counter bore set.
Sadly, I don't quite understand the reason for the counterbore. I've never used a timesert but I've done helicoils.
the insert has a small flange on it. You have to counter-bore for this to enable the insert to be flush with the surface. I used to only use helicoils but I now prefer Time-serts after i had a Helicoil fail on me. IMHO Time-serts are more fool-proof to install, and seem less likely to fail. Particularily if its an area where the bolt will come out for maintenance which is where my Helicoil failed after removing the cam cover for like the 20th time.


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I needed a bottoming tap once, and with none available locally (and my patience at a minimum that day) I ground a standard tap into one. Was cautious and used a fine silicon carbide wheel on my bench grinder. Used a normal tap to start down to its limit, and finished up with the modified tap. Wasn't for a Timesert, but should work the same.
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