My holdfast won't hold

[Mike Gabbay]

I just drilled the front row dog holes for my bench. I went to test them and put a Gramercy holdfast in and gave it a really good whack with my mallet and the piece of wood that was being held slipped pretty easily. All holes are drilled with a 3/4" spiral upcut and are .75" based on my calipers. Any tricks to getting these to hold?:bang:

http://www.toolsforworkingwood.com/Merchant/merchant.mvc?Screen=PROD&Store_Code=toolshop&Product_Code=MS-HOLDFAST.XX&Category_Code=TL

Other than that, the bench is really coming along. Next on the list is to cut the vise dog holes and the back row. Then its time for a finish sanding/planing and some finish. For the finish I was going to use BLO and mineral spirits. I'm not sure if I want a little poly in the brew as well. I did that for the base and it feels pretty good.

[glenn bradley]

I used thinned BLO as you describe. The poly will dry hard and be prone to cracking, chipping or scratching as I understand but I have no direct experience. The BLO has worked well for me. I'm also no help on the hold down as I don't have any. I must just be posting to hear myself type ;-)

[Chip Hamblin]

I found that after lightly sanding the shafts of the holdfasts with 120 grit they held well. By "lightly", I mean that I probably spent 10 seconds on each one. Hope this helps

[Jason Beam]

Mike, How thick is your top?

I had some trouble on really thick tops in the past. Over 4" seems to take quite a beating to get it to seat.

[Norman Hitt]

Mike, How thick is your top?

I had some trouble on really thick tops in the past. Over 4" seems to take quite a beating to get it to seat.

I seem to remember an "Old Codger" telling me something about the thicker the top is, it needs to have a "SLIGHTLY" larger hole than a thin top to get them to hold, since the holdfast cocks off of vertical and binds on one side of the hole at the top and at the opposite side of the hole at the bottom. With the THICK top and a small hole, the holdfast can't cock sideways enough to get a grip. I think he even told me how much to increase the hole size vs thickness, but that has been over 50 years ago, and "for some reason", I can't seem to remember "Details" very good.:rolleyes::rofl::rofl:

As a suggestion, you might try drilling a hole in a large scrap that was 2 to 3 inches thick and then tapping the hold fast in and see if it would hold a piece of wood satisfactorily and if so, then remove the holdfast and put it in a fresh hole in that same scrap wqithout tapping it in, and measure the angle from vertical, then make a hole in your top, sized so that it would give you the same angle and it whould work properly then.

let us know how it works out.

[Bart Leetch]

From Tools for woodworking's site

"Note: we have discovered that while the holdfasts work great they will work even better and in more benches if you just rub a little 150 or 220 sandpaper around the stems (not up and down, round and round)"
.

[Frank Fusco]

That is an unusual design for hold fasts. Not that it's bad but it is a departure from the traditional styles I have seen. Another difference I see is the smooth steel. Mine are Jorgensens and a more traditional style with a shorter arm than yours. And, they are cast. Meaning the iron (steel?) is rough. That might be a reason why they hold better. Dunno :dunno: just kinda guessing. I put a leather pad on. Helps hold and doesn't mar the wood.

[Mike Gabbay]

The top is 2 1/4" thick.

I'll try sanding them with 120 and see how that works out. Worse comes to worse I'll get a Veratas adjustable hold fast. You can never have too many tools! :)

[Jason Beam]

My top's 2 1/4" thick, too - i haven't drilled holes in it yet so I'm really hoping roughing them up helps you!! Good luck and let us know how it comes out! :)

[Mike Gabbay]

Success!

I used some 120 on the shafts (sanding horizontally) and they hold 10 times better!

Thanks everyone! :thumb:

[Alex Reid]

I'm a little late on this thread but Lee Valley has a nice hold-down that uses slight serations on the pole to grip the dog holes. It uses a 3/4" and has a threaded screw down for extra hold-down pressure on the piece.
http://www.leevalley.com/wood/page.aspx?c=3&cat=1,41637&p=31149