keep thread in alloy or thread insert/helicoil

[rodorico83]

Hello guys, I have this engine-gearbox sandwich plate to be used in a lola F3000, plate is alloy 6068 T6 I have a small concern about the threads for the studs that couple the plate with the gearbox, currently are directly made in the alloy of the plate, these threads have a length of 30mm, there are 4 studs (2 lower and threads for middle ones visible in the 1 picture) and then at the top it goes through bolts from gearbox to plate
I believe it should be ok as long as these studs are not taken out frequently and i apply some strong thread locker on them.
but i would like to get some opinions on this.

[jchracer]

Keenserts:

https://www.acmeindustrial.com/insert_comparison.html

[rodorico83]

Keenserts:

https://www.acmeindustrial.com/insert_comparison.html

thanks for the link.

[tstrong]

Assuming the loads and stud size/qty were analyzed correctly and as you state the studs will be semi permanently installed i would go directly with the base metal. That way if in the future on of the holes does get damaged it can be oversized for a Keensert. The keensert will give you slightly more load capacity just due to the slight increase in pitch diameter at the Al to SIL interface. Basically the difference in the OD of the Keenset vs the OD of the stud itself. So gain, my recommendation would be go directly with threaded hole and save the Keenserts for future repair. Todd

[rodorico83]

Assuming the loads and stud size/qty were analyzed correctly and as you state the studs will be semi permanently installed i would go directly with the base metal. That way if in the future on of the holes does get damaged it can be oversized for a Keensert. The keensert will give you slightly more load capacity just due to the slight increase in pitch diameter at the Al to SIL interface. Basically the difference in the OD of the Keenset vs the OD of the stud itself. So gain, my recommendation would be go directly with threaded hole and save the Keenserts for future repair. Todd

quantity and sizes should be fine.
thats what i though taking into account that studs will remain there and the thread length.
Thanks Todd