carcass saw drifting to the left

[Ron Bontz]

Hi Lowell. Thanks for the stealth plug. Intentional or not
As far as glue is concerned, I occasionally use a few drops of loctite, but I mostly just compress the spine slot. Glue does not make a joint. It simply strengthens it. I actually made a hydraulic jig a couple of years ago, maybe three years ago now, I forget, just for the purpose of compressing the entire spine at once. If done well the spine is as rigid and tight as any folded brass back. I actually ruined a saw plate the other day, because I couldn't get the plate out of the spine to correct a small misalignment. Opps! Should have left it alone. (&&(#(#&(&#*) Yep, I shall not type what I said. Plus you have a solid 3/8" of back you can shape, etc. I know, I know. Shame on me for sculpting the spine. I do have to be careful to "tension" the plate into the back, but a slotted back, unlike a folded back, has a repeatable reference point for the plate to seat against. Enough said about that.
Having mentioned folded backs, I will not say one type of back is superior to another as that is just an opinion and/ or marketing ploy in my view and, of course, always stirs up controversy. But rather say every type of saw back made has it's pros and cons. Including folded, slotted, laminated, and moulded. I have made steel folded backs in 10 gauge as well as 11 and 12 gauge and bought a few as well. I even have a couple of hydraulic presses sitting in my shop, strictly for that purpose. So maybe I will offer them some day. ( Some day ) Then again I have been telling myself, for several years, I am going to make myself a nice set of matching joinery saws out of Madron Burl with all the bells and whistles. Basically functional presentation saws complete with engraving. Hmmm. Well, Ok, so maybe that's someday too. Now back to work. Lunch is over. Best wishes. P.S. We are way off track now.

[Patrick Chase]

George,
I mis-spoke. I did bed mine in Loctite.

Since my daughter-in-law is in marketing for Henkel, I use Loctite.

Henkel bought Hysol a while back so they make great epoxies, too.

The slow-cure Hysols are right up with the best of them (West G-Tech, etc) and superior to any single-component adhesive for tough materials including smooth steel. Of course it helps to have a hot box, as the really strong-gripping, tough epoxies don't fully cure at room temp. IIRC Hysol 9460 only cures to 50% strength at 70F, for example.

Looking at spec sheets, Hysol 9460 scores ~3200 psi for lap shear on degreased (but not sanded/blasted) 1018. The corresponding number for Loctite 262 (the permanent kind, let's not even talk about removable threadlocker) is ~2000 psi.

Even room-temperature-cure Hysol 907 scores about 3000 psi for lap shear on steel, but it isn't as tough, gap-filling, or temperature-resistant as 9460. The catch is that it takes 3 hours to set and 24 hrs to cure at room temp, but for critical applications it's worth it (and if you have a hot box you can get the cure time down to a couple hrs).