ChattyMatty

I've seen people talk about countersinking the screws on the upper deck of double deck carbon chassis cars as a means of eliminating 'on-the-fly' tweak issues (read: hitting walls). My question is that unless you have a handy dandy CNC machine to do the countersinking for you, don't you introduce the possibility of 'Demel tool induced tweak' in that the chamfer you put in the hole by hand will never be as perfect as the CNC hole location from you car manufacturer?

Anybody ever tried good old-fashioned star washers for this purpose?


Still a NuB,
-M

sidecarphil1

iTrader: (1)

maybe try with a bigger drill bit and only drill the conical start of the drill bit

this will put a countersunk hole in for you , we do it if we need this in cars at work

academygaz

If you look at all the current chassis from the past 3 or so years, none of them (apart from the TC5 I think) have a countersunk upper deck, as manufacturers realised that tweak can happen because of the countersinking (the chassis twisting, and the countersinking grabbing onto the screws, stopping it going back to the original form).

pinggoy

iTrader: (24)

you can buy countersunk washers...

Greg Sharpe

iTrader: (15)

All the countersunk holes I have drilled over the years in r/c chassis, decks, towers, braces, nerf wings, etc. have all been drilled with an actual countersink drill bit ( http://www.mcmaster.com/#countersink-drill-bits/=3pqei7 ) in a simple, small, inexpensive Craftsman drillpress. Harbor Freight also sells hobby grade drill presses that work great for this type of work. The best part about using this method is that the countersinking bit self centers in the bolt hole, so you don't even have to clamp the piece down, nor worry that it is misaligning the bevel.

heretic

Exactly, and exotek offer a non-countersunk top plate for the TC5 just to address this problem.

Also, Xray has non countersunk top plates with very cleverly designed screws that center the top plate even better than anything else.