T-rail Q's

[Ssonerai]

Between finishing a roof and getting firewood in for the winter, i have been picking away at the wife's 1926 BBC table.
Got the blinds down from the loft to start repairing them, and a couple rails to try to remember how they go back together.

Here's the Q: given how crushed all the bolt holes on the blinds are, are the blinds supposed to provide a reactive force to support the rails from tipping out?
This bolt area at the end of each blind can't just be cosmetic, someone was reefing on them over the ages, most likely for a structural support reason? Or is this just from trying to keep the pocket irons tight?

I really want to understand this, and to take preventive measures now. If the blinds are just cosmetic, I'll patch and putty them and keep moving forward. If there is a structural issue here, then maybe ripping off the crushed ledger and replacing with something dense like ipe, or at least hard maple? Originals are soft poplar and obviously not up to the duty.

Also, rails are BRW as seen. The head rail (obviously at the window end of the room ) is bleached out from sunlight. Is there a good product to restore the color with minimal sanding? All the other rails are pretty much like the dark/foot end. I do not plan to put a film finish on. Just Penofin and carnauba wax. But any other advice welcome about bringing the color back.

Thanks!
smt

 

[bradsh98]

Nothing structural. Just keeping the irons tight. Naturally, the less vibration, the better, as there will be less energy loss.

 

[Ssonerai]

That's reassuring.
I'm on the fence.
Those holes are all crushed in, not countersunk.
Leaning strongly to ripping off the old and replacing with ipe.
("crush this")
Will think about it while stacking last load of firewood delivered this AM.

Thanks, Geoff.

smt

 

[Tennesseejoe]

Do not overtighten the rails... the proper torque has been mentioned here before ....do a search

 

[Ssonerai]

... the proper torque has been mentioned here before ....do a search

1.) I think you are wrong. These are T-rail blinds, not rail bolts. Nor are the actual rails overlay rails, like GC's

2.) it's a bit late - 94 yrs of installers before me have already been at them.

The reason i asked the original Q is that the underside of the blinds (black painted crushed wood strips) butt the frame of the table, more or less, and could provide a reacting force against tipping. Though if so, it is not ideally designed. (Geoff assured me that design-wise, there is no original intent toward that effect). My other reason, still related somewhat to energy management, is that the "nuts" for the bolts are actually the threaded ends of the pocket irons. Secure irons might enhance the stiffness between adjacent cushion rails so long as the tension does not cause a displacing force.

My choices are how to change the design, or whether to repair & re-install as is.
The latter is my option for the time being.
They can always be replaced later.
(They are done, pics to be posted to my restoration post later)



I am musing on the prospect of including belleville washers under the slate bolts (separate item) and how many/what tension would be effective to accommodate seasonal MC changes....

Not that there's any problem that needs be left uncomplicated if a dedicated person applies their perspicuity to it.

Have a great Thanksgiving, everyone.

smt

PS: peripheral to the discussion but interesting to me: in researching pocket irons and such, it appears that a number of manufacturers still use the T-rail design and barrel nuts in the slate. I thought the system was obsolete. For instance, A.E. Schmidt tables are respectable enough in the sense that they seem to embrace some level of performance and quality materials. AFAICT, all, or at least most of their better tables are still T-rail design.