20mm or 21mm bit for KD fitting?

[Mike Weaver]

I'm doing a favor for a friend and trimming some melamine shelves to save him the cost of buying new ones...

Some of the shelves use some sort of a knockdown cam joint and I need to get the correct drill bit to redrill the holes.

The cam measures 0.80", but that converts to 20.32 mm - do I want a 20mm bit, or a 21mm bit?:confused: What's common for these - anyone know?

Thanks in advance,
-Mike

[Rick Lizek]

Used a lot of Ready to Assemble (RTA versus the old term KD, knock down...which sounds like better quality from a marketing stand point) fittings in the business over the years and not sure what you have exactly but logic would dictate a 21 mm bit as 20 would be to small to fit. The cam should be able to turn easily.

[Mike Weaver]

Used a lot of Ready to Assemble (RTA versus the old term KD, knock down...which sounds like better quality from a marketing stand point) fittings in the business over the years and not sure what you have exactly but logic would dictate a 21 mm bit as 20 would be to small to fit. The cam should be able to turn easily.

Rick,
You're absolutely correct - 21mm makes more sense.

RTA does sound much better too.

Thanks,
-Mike

[John Renzetti]

Hi I use these types of knock down fittings. They are commonly called Rafix. I use a 20mm bit to bore the hole. You might want to make a boring jig so that you can line up the edge of the workpiece in the exact location called for. Also the screws that the fitting slips over need to be exactly positioned also. Once you get the hang of the installation you'll find these things have a lot of uses. I use them a lot for closet systems to lock the main components into place.
take care,
John

[Mike Weaver]

Hi I use these types of knock down fittings. They are commonly called Rafix. I use a 20mm bit to bore the hole. You might want to make a boring jig so that you can line up the edge of the workpiece in the exact location called for. Also the screws that the fitting slips over need to be exactly positioned also. Once you get the hang of the installation you'll find these things have a lot of uses. I use them a lot for closet systems to lock the main components into place.
take care,
John

John,
Thanks!
-Mike

[Rick Lizek]

http://www.woodfit.com/product_info.php?name=Rafix%20Knock%20Down%20Fitti ng%20-%20Zinc&products_id=145
If that's the Rafix then 20mm is as John specified. I've used a lot of other types and 20mm would be undersized.

[Mike Weaver]

http://www.woodfit.com/product_info.php?name=Rafix%20Knock%20Down%20Fitti ng%20-%20Zinc&products_id=145
If that's the Rafix then 20mm is as John specified. I've used a lot of other types and 20mm would be undersized.

The one he is using looks like a plastic version of that exact fitting w/ a metal insert for the screwdriver. Thanks for the link.
Cheers,
-Mike

[John Renzetti]

Hi, The Rafix are based on the European 32mm system. I'm sure there are other types that use the Imperial system. The 20.32mm sounds like the Rafix since you do need to tap them into the 20mm hole for a secure fit.
Mike I've scanned the page from the Hafele catalog that shows the boring diagrams for setback, depth etc. I couldn't attach it to the email I just sent you from this site. Let me see if I can attach it here. I haven't done this before so bear with me. I think this worked.
take care,
John

[Mike Weaver]

Hi, The Rafix are based on the European 32mm system. I'm sure there are other types that use the Imperial system. The 20.32mm sounds like the Rafix since you do need to tap them into the 20mm hole for a secure fit.
Mike I've scanned the page from the Hafele catalog that shows the boring diagrams for setback, depth etc. I couldn't attach it to the email I just sent you from this site. Let me see if I can attach it here. I haven't done this before so bear with me. I think this worked.
take care,
John

John,
Thanks again! Yep, I think 20mm is the way to go... The cam was in the hole quite firmly and had to be *carefully* pried out so that I could cut 1/2" off the shelf length.

Thanks for the catalog page.

Cheers,
-Mike