Substrate thickness for holdfast

[RickCarpenter]

What is the minimum substrate thickness for an old-time holdfast (galoot-ish, not the Veritas type)? I am building a version of the Roubo bench where holdfasts will be used in the front apron. Believe it or not, I've heard of a maximum effective thickness, but I'll not approach that thickness.

Rick

 

[houtslager]

Roubo bench iirc was /is 4 1/2"thick so anything thicker then 2"will do it justice.

 

[bugbear]

http://nika.frontier.iarc.uaf.edu/~cswi ... =1#message

BugBear

 

[Paul Chapman]

Hi Rick,

In Bugbear's link someone mentions the Record holdfast which fits into a metal collar bolted to the bench. This metal collar takes most (if not all) of the strain, which would make the thickness of the bench or apron less important. I suppose it all depends how Roubo-authentic you want to be. I've used a Record holdfast in a bench and a Workmate (the original Mate Tools version with the beech vice bars) for years. If you are making your own Roubo-style holdfast it might be possible to make up a Record-type collar as well.

Hope this helps :wink:

Paul

 

[RickCarpenter]

Thanks for the replies, y'all. I emailed Chris Swingle last night and he replied to me rather quickly also. Reading the very informative link BugBear provided points me as well to the reply from Chris. He told me to experiment with hole diameters on some scrap first, so I think that's what I'll do.

Paul, I don't want to do the metal collar... for now. My apron will be 2.25 inches thick (covering houtslager's recommendation), which is three 1x boards glued together, and I think that may be just right. If I need the collars, I can always fit them in later.

Thanks again,
Rick