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View Full Version : Ideas on hole patterns for 2-4-6 blocks? And an A2 HT question.



cpm10v
03-05-2005, 11:50 AM
Anyone have any ideas regarding hole patterns and/or what types of holes to put into a set of 2-4-6 blocks I'm making? I generally just use 1-2-3's to block stuff in on the SG or as a reference to measure off of or from or to set something up on the mill. The only purpose I typically have for holes in these blocks is for weight savings, as I find tapped holes tend to trap and hide grit and what not. Anyways, any ideas on what type of holes to put in them aside from lightening holes? Another thing, do you think a 2" thick section of A2 will have a hard time completely transforming/quenching in still air or should I press quench them between two steel plates and have a fan blowing on them? I don't have the facilities to flash quench in oil unfortunately or I'd do that.
Thx,
Greg

sch
03-05-2005, 03:04 PM
If doing your own, then holes big enough to
pass 1/2" studs easily would be useful. I
found last summer when I spent a month
clamping 6x12x3/4" plates in a P&W boring
machine that the 123 blocks made by students
were much more useful with their 1/2" clearance holes than my Chinese 123 blocks
with 3/8" holes. Clamping sets for larger
machines use 1/2" studs. Work arounds were
available but I sure wished for larger holes
the first week of fixturing. Steve

moldmonkey
03-05-2005, 05:15 PM
May I suggest a few reamed holes for dowel pins that are square to the outside edges. If you ream the same pattern in say a angle plate you can just install the block on the plate for fixturing without having to indicate it square. You could then carry the same pattern over to V-blocks, toolmaker's vise, fences, fixture plate, etc. to make a whole interhaneable system. Suburban Tools charges big bucks for their system.

Jon

[This message has been edited by moldmonkey (edited 03-05-2005).]

Jim Luck
03-05-2005, 06:03 PM
Both sch's and moldmonkey's ideas are the way to go. Don't worry about heat treating. Just make sure you soak it at temperature for the proper length of time for the thickness, plus a couple of minutes. Don't forget to draw it back!. You don't have to put holes in, but it's a good idea, especially if you use the two hints!