Pretty sure the tap that comes with that kit is not the bottoming tap.DO NOT grind the tap. It is onley tapered for 2 threads. Yoiu must have a taper for it to cut.
If you leave 4 tapered threads the screw will still go in but it will be tight at the bottom. That makes the threads stronger.Pretty sure the tap that comes with that kit is not the bottoming tap.
The bottoming tap has only 2 tapered threads (and doesn’t need to be ground).
The STI tap has 4 tapered threads and needs to be ground if you want to thread more than 2 or 3 M6 threads...
Interesting suggestion.If you leave 4 tapered threads the screw will still go in but it will be tight at the bottom. That makes the threads stronger.
You have extra helicoils so I suggest you try it. You can remove helicoils by grabbing the top with needle nose plyers and pulling it out.
It won't damage the threads.
Cool. And how many M4 threads were you able to engage into that tapered Helicoil?I'm saying you can grab the top thread of the helicoil and pull it out. It uncoils.
My holes are about 7mm deep.
I did two holes with a tapered tap and I could screw the stud to the bottom of both. It got a little tight at the bottom. So, no loctite needed.
I think you better get something that won't allow you to drill more than 7mm deep.
If you sink a drill bit into the cell you might have flames shooting in your face. Might be amusing if you are wearing fire fighter gear.
The screw went to the bottom. I had 4 threads in there so 4 engaged.
So do you think even the standard tapered (4 tapered coil) tap would be hard to tap straight with a press or a jig?I didn't use the drill press to drill my holes. But I used it to start the tap straight. It is harder to start a tap straight when it has less taper.
Yeah, if I drill I will make a stop first. All this DIY stuff is fun, but not worth a trip to the Emergency Room...I think you better get something that won't allow you to drill more than 7mm deep. If you sink a drill bit into the cell you might have flames shooting in your face. Might be amusing if you are wearing fire fighter gear.
I didn't get 7 tapped threads. My hole was 7mm deep in the middle. My flat bottom drill went about 6.5mm deep. The tap only went 6mm deepWow, so the taper was gentle enough to allow all of first tapered thread to engage M6. You modified a 6 coil Helicoil to make a 4-coil Helicoil, correct? So 4 coil threads engaged into the top 7 tapped threads and the bottom 3 tapered threads remained infilled.
You could use some kind of tap guide but the easiest way for me is in the drill press. I just put the tap in the hole and hold down on the handle while I turn the chuck with my other hand to get a couple threads started. Then the thread axis is perpendicular to the terminalThe top 3 Helicoil threads were full-diameter and only the 4th Helicoil thread has slightly reduced thread due to the taper of the tap. And an M6 grubscrew was able to thread through art 4 Helicoil threads including that last tapered thread and reach the bottom.
Very helpful, thanks.
So do you think even the standard tapered (4 tapered coil) tap would be hard to tap straight with a press or a jig?
As they say, ‘you only get one chance to tap a straight thread’...
Yeah, if I drill I will make a stop first. All this DIY stuff is fun, but not wirth
I didn't get 7 tapped threads. My hole was 7mm deep in the middle. My flat bottom drill went about 6.5mm deep. The tap only went 6mm deep
The top of the helicoil has to go 1/2 turn past. So, I put 4 threads in 5.5mm of tapped threads. And the bottom was defiantly tapered.
It’s true that the tap is shorter than a drillbit, so I should check whether I can fit a cell under my small HF press with sufficient room for the tap.You could use some kind of tap guide but the easiest way for me is in the drill press. I just put the tap in the hole and hold down on the handle while I turn the chuck with my other hand to get a couple threads started. Then the thread axis is perpendicular to the terminal
Never had to use one, but it may finally be time...
I used the cheap HF drill press. You have to rotate the table out of the way and set the cell on the base of the drill press.‘Defiantly tapered’ - I like that .
Ok, so the tap went down 6mm out of which only the top 2 threads were straight and then two coils were tapered and you succeeded to thread an M6 grubscrew through all 4 coils, right?
It’s true that the tap is shorter than a drillbit, so I should check whether I can fit a cell under my small HF press with sufficient room for the tap.
I think you can fit a 1/4" drill bit in there. If not you can rotate the whole head off of the base and set the cell on the table.No way I could get a 1/4” drillbit ie with enough space to slide a 280Ah cell under it, but a tap, maybe...
Overkill Fortune cells have very strong stainless postsIf you use JBweld, Loctite or any other thread glue, be very careful not to get it on the terminal pad..... it will create a slightly resistive barrier that is a bitch to debug. (don't ask how I know that!! ?)
Also, Don't count on any of the thread glue products to add much strength. You can have the best glue in the world... but it will pull out along with the soft aluminum threads.
The next time I purchase cells I am going to investigate having fortune style post laser welded on. I have thought about talking to Amy about it but I don't want to start the conversation if I am not ready to buy. What would be ideal is if she just carried a line of cells with the posts that we could order.
OK, so I just got one of these, but I figured being a tap to M6 thread, I should get metric.My EVE 280's are measuring 7mm+ deep. One of them is stripped so I'll be doing this soon. I do have a cheap drill press but in lieu of that you can use something like https://www.amazon.com/gp/product/B00J3ZYEJQ/
I have a bottoming tap but even that won't put threads all the way down. I may cut off the tip of a 1/4" bit and possibly the tap, too. I'll do a video on it ... watch my channel (I'll never remember which thread to post the results in lol)
Found the tap specs and the M6 Helicoil tap has a thread diameter of 7.422mm (wish I’d though of looking this up before ordering the tap guide).OK, so I just got one of these, but I figured being a tap to M6 thread, I should get metric.
The shank fits 7mm perfectly but the threads are slightly larger than that and won’t fit through the 7mm hole. The threads fit through the 7.5mm hole but there is enough play that I don’t think it will do the trick.
So now that I’ve understood that you got a Standard tap guide, am I correct that the threads of the M6 Helicoil tap fit snugly into the 9/32” hole?
That’s what I expected (and why I purchased a metric tap guideThe helicoil kit I purchased came with an M7 tap and requires a 1/4" drill bit. The resulting threads in the aluminum before the helicoil is M7. After helicoil it's M6 of course.