What is the best Chop thickness for end vise with dog hole

[Jon Crafting]

Hi guys, this is my first post on these forums so my apologies in advance if my noobiness shows through.
I am currently working on a design for my first woodworking bench and would like to make a small end vise with a dog hole in the chop so it could double as a wagon vise. I'm wondering if there is a general rule of thumb for how thick the chop would need to be to support a dog and withstand the clamping pressure without blowing out. The bench will have a solid 3" top, if that ties into the equation at all.

Thanks in advance for any enlightenment you can provide.

-Jon

[glenn bradley]

Probably as many variations on this as answers. I have a small work holding station that uses a 1" chop with a 3/4" round dog and is fine for smaller stuff. My main bench chops are 2"-plus thick with four dog holes along them and I can pretty much crush things if I am not careful.

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[Jim Becker]

What material you use is going to be part of the equation, too...

[Jon Crafting]

@Glenn - Thanks for the references, that helps at least get be started.

@Jim - Good point. While I know hardwood would be best, if I use yellow pine would you think that 2" would be adequate or would I need to go thicker such as 2.5" or 3"?

Thanks,

Jon

[Derek Cohen]

I would be using hardwood (and Australian timber is Hard). If you plan to use yellow pine for a tail vise, thicker would be better (Yellow pine is not one found in Oz, but my understanding is that it hardens as it ages?). Still, you are not going to crank down that much, so 2" should be fine (with a 3/4" dog hole centred). Watch the grain direction - creating a quartersawn edge on the top side might be a recipe for splitting.

Regards from Perth

Derek

[glenn bradley]

I would do some testing with your pine. Most pines are well under 1000 on the jamka scale where something like American beech is 1300 and hard maple is 1450. You will be applying pressure via a screw. Your leverage will be substantial (you won't need much to hold your work). On the other hand, if the pine fails you just make a new chop. If it doesn't, you're golden.

[Tom Bender]

As you said "first bench" don't overthink it.

[Jon Crafting]

Thanks again for the feedback guys. Great points all.

@ Tom - True, but the planning is part of the fun too The goal I guess is to not over plan it to the point where it gets too complicated to even start.

@ Glenn - "if the pine fails you just make a new chop" is an awesome bit of advise. That bit along with Tom's took out the little bit of worry I had, and I'll just go with it and see how it works.

@ Derek - Good point. I'm not sure I'd have oriented the grain incorrectly, but it also wasn't something I was thinking about so thanks for bringing that up.

Cheers!

-Jon