Size between bulkhead and drillbit?

Embowe · 02/05/2007, 03:43 PM

Ok..I am getting ready to drill my tank finally. I know they say to drill the hole a little bit bigger than your bulkhead but how much bigger... by my calculations the hole I need to drill will be 47.2MM (1 and 7/8) and the bit I have is 50mm...that would be roughly a 3mm diff. Would that be enough or is it actually too much "slop"

Joshua1023 · 02/05/2007, 03:50 PM

I encountered the same issue recently. I had a 1/4" oversize from the closest bit I could find. I was a bit close for comfort for me so I sandwiched the hole w/ two pieces of acrylic drilled to the exact size and siliconed into place. Of coarse mine was just a 5/8 hole. One and a half mm all around a bulkhead that size SHOULD be fine.

MCary · 02/05/2007, 03:52 PM

Most places you find bulkheads, the size of the hole is listed. A hole for a 1" sch 40 bulkhead is 1.75 inches. I believe 1 7/8 is the hole size for a sch 80 bulkhead. The flange is pretty big, I would think a 50 mm hole would be fine, but if your uncomfortable then I would order a new bit. You can get them on E-bay for less that $12 shipped from hong-kong and recieved in less than a week.

Mike

Embowe · 02/05/2007, 06:24 PM

The thing was I had a brand new 50mm bit in my work and was just going to use that...and yes a 1" sch80 is a 1 7/8 hole.....1.75 is 44.45 ...so ideally a 45mm bit would be great? Correct?

loves saltwater · 02/05/2007, 06:31 PM

Yes 45 MM for a 1" bulkhead

02/05/2007, 03:43 PM	#1
Embowe Registered Member Join Date: Sep 2006 Location: South Jersey Posts: 331	Size between bulkhead and drillbit? Ok..I am getting ready to drill my tank finally. I know they say to drill the hole a little bit bigger than your bulkhead but how much bigger... by my calculations the hole I need to drill will be 47.2MM (1 and 7/8) and the bit I have is 50mm...that would be roughly a 3mm diff. Would that be enough or is it actually too much "slop"

02/05/2007, 03:50 PM	#2
Joshua1023 Registered Member Join Date: Oct 2006 Location: Reading PA Posts: 1,526	I encountered the same issue recently. I had a 1/4" oversize from the closest bit I could find. I was a bit close for comfort for me so I sandwiched the hole w/ two pieces of acrylic drilled to the exact size and siliconed into place. Of coarse mine was just a 5/8 hole. One and a half mm all around a bulkhead that size SHOULD be fine. __________________ Only bad things happen fast. Only bad thing happen fast. Only bad things happen fast. Man,I'm friggen hard-headed!!! Current Tank Info: 90 gl tank,Coralife 14K MH lights,2 Current dual daylight/actinic 40 watt fixtures, tidepool sump,Coralife SS 220 protein skimmer,six inch sand bed w/ plenum, Current Prime Tower 1/3 hp Chiller,RedSea ozonizer w/ orp

02/05/2007, 06:31 PM	#5
loves saltwater Premium Member Join Date: Oct 2006 Location: Katy,Tx Posts: 945	Yes 45 MM for a 1" bulkhead __________________ Does anyone have the number to Reef Keepers Anonymous! AM- 0 Rite- 0 Rate- 0 Phos- 0 PH- 8.0 SG- 1.026 Cal- 420 KH- 8.0 dKH Alk- 2.51 meg/L Mag- 1350 Temp-78-80 Current Tank Info: 125RR/30 gal DIY sump-fuge/100 lbs of LR/PM Bullet Skimmer/1000GPH Closed loop/T5 4X54 Watt HO

02/05/2007, 03:52 PM	#3
MCary Premium Member Join Date: Dec 2002 Location: Hardin, Montana Posts: 3,142	Most places you find bulkheads, the size of the hole is listed. A hole for a 1" sch 40 bulkhead is 1.75 inches. I believe 1 7/8 is the hole size for a sch 80 bulkhead. The flange is pretty big, I would think a 50 mm hole would be fine, but if your uncomfortable then I would order a new bit. You can get them on E-bay for less that $12 shipped from hong-kong and recieved in less than a week. Mike

02/05/2007, 06:24 PM	#4
Embowe Registered Member Join Date: Sep 2006 Location: South Jersey Posts: 331	The thing was I had a brand new 50mm bit in my work and was just going to use that...and yes a 1" sch80 is a 1 7/8 hole.....1.75 is 44.45 ...so ideally a 45mm bit would be great? Correct?