Hole sizes for water jetting parts

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mmarien
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Joined: Thu Jul 23, 2015 9:50 am
Location: Saskatoon, Saskatchewan, CANADA

Hole sizes for water jetting parts

Post by mmarien »

I was going through the plans for all the metal parts. I'm going have them cut with water jet. I noticed the note on the "06 Spar Fittings" drawing the indicates that the holes are drilled undersized and reamed to 5/16". The holes for the AN3 bolts are shown as 0.187 so they are drilled to size. But because the water jetting isn't all that accurate I was going to cut the holes smaller and then just drill (or ream) them to size.

Reading through the form, quite a few builders have had the parts cut with water jet but I didn't find any mention of what size they had the holes cut. Any suggestions on what size should be used for water jet cutting for the 3/16" bolt holes?

As an aside the "COMPRESSION-TUBES.dwg" from the web has an error in the TB-4 part. The holes should have 1.5" between them. The one hole is drawn 1.813" from the other one. It is right at the bend.
Murray Marien - HC 0180
Saskatoon Canada
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dougm
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Re: Hole sizes for water jetting parts

Post by dougm »

The holes on most of the CAD parts are 1/16". This was for two reasons as I understand it. 1. allow for accurate finishing to final diameter, 2. save a little $$$ re: machine time. Takes time to cut all those holes.
Doug
Building Hatz Classic s/n 093 & Rotec R3600
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mmarien
Posts: 178
Joined: Thu Jul 23, 2015 9:50 am
Location: Saskatoon, Saskatchewan, CANADA

Re: Hole sizes for water jetting parts

Post by mmarien »

Thanks. Makes sense.
Murray Marien - HC 0180
Saskatoon Canada
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