From the first Worthington reel mower made in the late 1800's to present the assembly containing the bed knife has always been referred too as a bed bar assembly.
Some reel mowers have fixed bed bar assemblies, some rely upon the reel itself to be moved.
Some of the earlier JD reel mowers had a floating reel that required continual adjustment, same with the Tru-Cut/Eastman, California trimmer - all had fixed bed bar assemblies. Essentially all commercial reel mowers now utilize a concentric bolt assembly or four pivot points to move the bed bar up/down, side to side and front/rear to achieve the proper set-back.
Regarding mounting the bed knife to the bed bar, I have never seen nor heard of "slop" in these bolt holes. Once the new knife is mounted to the bed bar a hand impact wrench/hammer is used to firmly tighten the knife to the bed bar. No wiggle room at all.
I have seen sprung frames (out of square) on especially the McClane and Tru-cut/Cal trimmers which made accurate reel to bedknife adjustment virtually impossible - which is why when quoting reel grinding prices these mowers will cost as much as 300% more to spin grind and relieve properly.
For instance, say you have a Toro series 5 greens mower, eleven blade reel and want the reel ground. Typical cost if you remove the bed bar assembly is around $125.00 with the new bedknife being squared to the bed bar prior to re-assembly. Parts not included.
Show up with a floating reel mower like the McClane/Tru-cut and I will first closely examine the reel assembly for square. If it passes inspection then the price for a grind/relief with a new bedknife starts at $250.00. If the frame is not square and sufficient clearance exists on the reel figure t least an additional $75.00. Even on a Foley Dual Express instead of my Neary 180 squaring these machines to the grinder takes a good forty-five minutes of constant tweaking due to the rear drive wheels not being uniform in size. Plus, the bed bar assembly is an integral stressed part of the frame which requires removal for grinding clearance so now you have to allow for frame distortion as well. Figure in at least thirty minutes for dis-assembly and initially mount on the grinder. Then a good thirty minutes more of dicking around squaring the reel to the grinder, maybe twenty minutes to grind then a good four-five minutes for re-assembly and clearance adjustment. A good 2 to maybe 2 and a half hours to grind.
This is why I so dislike these mowers, not from their quality of cut but their difficulty in truing for an accurate grind and relief.
Bear in mind even a "cheap" grinder like my Neary cost over $10,000 when new. A Land Pride or Foley Dual Express without the cabinet or computer controls runs around $35,000 to start. Used my Neary is still worth over $5,000 and I haven't seen a Land Pride or Foley in decent shape for less than $12,000 in over fifteen years. Add in the cost for a bedknife grinder or attachments to convert the spin grinder like I can on my Neary for $400 and now you can see why grinding is so expensive.
Inexpensive reel mowers more than make up for their cheap cost in terms of additional labor to grind properly.
When I conducted my mower trials back in 2002-2003 I took all of this maintenance criteria into consideration when evaluating use and cost of operation. I was surprised at how well the Hiayter performed especially when factoring in the cost to maintain.
Nice Try = You Suck Spelled Differently