Coil over sizes

[dave@threat]

When it comes to shocks you get what you pay for. FOA out of the box are junk IMO. Every single FOA I have revalved had shavings in the oil, shavings still attached to the piston, and pipe dope in the oil. Those are easy fixes though. After you fix there mistakes they actually perform quite well once they are dialed in. My main complaint about there products are the extremely loose tolerances in all areas of the shocks. I am especially not a fan of there bump stops. Their is WAY to much play in the shaft on the bump stops.

 

[c_note]

Straight threads? FOA's use very coarse threads, which are less prone to stripping then fine threads. Plus with the coarse thread adjusting them is alot easier. With the FOA's get the billet ends and upgraded seals. cheaper then any of the "big" names and a great product. Check out the King of Hammers race. Alot of the field was running FOA's only breakage was a shock shaft due to the rig breaking down and the other competitors having to crawl over the downed rig as it blocked the race path. Im sure your buddy is good at what he does but he sounds like most other guys who short change FOA due to them not being a "big" name brand.

you gotta be kidding me! fine threads make more surface contact and make a stronger thread than coarse threads.

 

[Toreadorranger]

you gotta be kidding me! fine threads make more surface contact and make a stronger thread than coarse threads.

Holding strength and resisting stripping are two different things. A fine is on average 10% stronger in holding then a coarse, but a coarse thread given the same thread engagment is less likely to strip. So, no Im not kidding you.

http://www.fastenal.com/web/services.ex?action=ScrewThreadDesign

http://www.britishfasteners.com/threads/bsw.html

http://www.tapmatic.com/tech_manual/drill_depth.html

 

[c_note]

Holding strength and resisting stripping are two different things. A fine is on average 10% stronger in holding then a coarse, but a coarse thread given the same thread engagment is less likely to strip. So, no Im not kidding you.

http://www.fastenal.com/web/services.ex?action=ScrewThreadDesign

http://www.britishfasteners.com/threads/bsw.html

http://www.tapmatic.com/tech_manual/drill_depth.html

what they are talking about on the stripping is the lead of the screw when you initially thread the screw into a hole.

plus a fine thread like on a shock is better for fine tuning your preload.

 

[Toreadorranger]

what they are talking about on the stripping is the lead of the screw when you initially thread the screw into a hole.

plus a fine thread like on a shock is better for fine tuning your preload.

Read that again, they say for the same thread engagement coarse resists stripping easier, which means after its all ready been threaded.

 

[dogboy]

If I had to guess, I'd say that the course thread would resist stripping, better. That is what my common sense tells me.

On a side note, I won't be doing coil overs. I bought a 93 Ford Probe gt 5spd on Wednesday, so money is not going towards the truck anymore.

 

[c_note]

If I had to guess, I'd say that the course thread would resist stripping, better. That is what my common sense tells me.

so ive been a machinist for over 6 years and ive done thread repair on aircraft until now. what i have gather from my experience with threads is that fine threads strip during assembly and dis assembly. coarse threads strip under load. the reason for that is that fine threads have a tighter class of fit so if the threads have any dirt or chips in them they will strip. coarse threads strip when being tightened under load because the class of fit is loose. they are made that way for quick and frequent assembly thus making them less vulnerable to stripping. still, under load a fine thread will hold better.
thats from my experience as a machinist which during my time as a repairman, i extracted aleast three broken screws during the regular work day.