Drill size question

[Charles in SC]

I am working on the canopy where the side skirts bolt on my slider. The plans say to drill #30 holes in the skirt c-660 & c-659 where the #6 screws go thru and a 5/32 in the canopy. A #6 screw will not go thru a #30 hole so this needs to be bigger, I am thinking a #28. Does anyone se something wrong with this or am I missing something.
Thanks!

 

[D-Dubya]

I'm doing a tip-up, but I think the reasoning is the same. If you have to countersink a hole, you need the #30 hole to use as a pilot for the countersink bit. You do NOT want that countersink jumping around and chattering on the Plexi. After you have all the countersinking done, you can enlarge the holes to the #6 screw size using a 5/32" Plexi bit so the screw will fit through them.

Since the countersinks only come in a few select sizes, you just have to take all the drilling in steps until you're ready to enlarge them to the final screw hole size.

Maybe a slider builder can chime in and correct any misconceptions I may have, but hopefully this gets you in the ballpark.

 

[Charles in SC]

Thanks Dave , I am with you on all that, the plexi is done, drilled, countersunk and enlarged. My question is about what size to enlarge the holes in the aluminum to for the #6 screws.

 

[Rick6a]

....A #6 screw will not go thru a #30 hole so this needs to be bigger, I am thinking a #28....

Charles,

As builders, we are often faced with problems as you describe. The easiest way to help quickly determine the correct size drill bit in any situation is to measure the fastener's shank with a micrometer then refer to a drill index chart for the appropriate drill bit. If you seek optimum hole quality, you will find the technique handy now and in many other situations in the future.

 

[clevtool]

Correct #28 is the correct size for the #6 screw. The larger hole in the plexi is so the screws don't bind on the plastic.

 

[AltonD]

Use a #27. The goal is for the #6 screw to have some wiggle room for thermal expansion of the plexi.

 

[Charles in SC]

Charles,

As builders, we are often faced with problems as you describe. The easiest way to help quickly determine the correct size drill bit in any situation is to measure the fastener's shank with a micrometer then refer to a drill index chart for the appropriate drill bit. If you seek optimum hole quality, you will find the technique handy now and in many other situations in the future.

Thanks Rick, that is how I came up with a #28 drill. It is done now so I am on to the rear skirts.

 

[rzbill]

Yep

Use a #27. The goal is for the #6 screw to have some wiggle room for thermal expansion of the plexi.

Either the prints or a comment in the instructions say to use a #27 for the aluminum and also 5/32 for the plex.

I think it is buried in the instruction text. I know at this stage many (like me) are looking at the prints more than the instructions. I called Vans to find out the hole sizes (they gave the above) and then I found it in the instructions while perusing them at a later date.