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Beveled Finger Shims?

Beveled Finger Shims?

Beveled Finger Shims?

(OP)
Anyone aware of any finger shims that are beveled and commercially available?

RE: Beveled Finger Shims?

Explain beveled. Most shims I buy at Lowe's are triangular in shape - just shove them in and they work??

RE: Beveled Finger Shims?

(OP)
Basically a beveled washer with a slot rather than a hole.

RE: Beveled Finger Shims?

Beveled shim might create problems. All surfaces in firm contact... A beveled shim implies that a portion of the faying surface is in contact. If the gap is sufficient to consider "special" machined fills, there may be another problem. I have not used beveled washers, but the intent is to keep the faying surfaces in contact, therefore the beveled material is not located between the plies.

If the connection is fabricated to a skew different than the support, I may suggest repairing/adjusting the connection material. If the gap is small and material relatively thin, can the gap be closed by simply applying tension to the bolt? Does this connection require slip critical?

what is your condition?

www.FerrellEngineering.com
Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.

RE: Beveled Finger Shims?

(OP)
Connect-
Glad to see you are here.

This is bizarre situation.

I have a very light truss/frame.
The "top chord" is a light L2x2 and the purlin that runs over top is at a skew to the truss chord such that it only makes contact on the heel of the angle.
When the bolt to the purlin bottom flange is tightened, the angle leg easily bends to meet the purlin flush.
I have not been able to find any information on whether or not it is permissible to draw the angle leg tight. In this case, the leg has to bend up 0.2" on the tip of the outstanding leg.

RE: Beveled Finger Shims?

As a bearing condition, this is not an RCSC issue. I think you are on the right track with a shim to provide a bearing surface. Drawing the angle up to the purlin is counter-intuitive for bearing. A machined tapered shim might be un-necessarily expensive. Maybe a combination of 1/8" finger shims at staggered depth and tightening will be sufficient. I expected that the loading is very small.

www.FerrellEngineering.com
Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.

RE: Beveled Finger Shims?

(OP)
The more I look at it, the connection would require to shims otherwise the bolt head or nut will not be 90º to the surface on which it is bearing.

RE: Beveled Finger Shims?

A beveled washer would be required under the head or nut, whichever is at the purlin. And also shims in the gap.

www.FerrellEngineering.com
Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.

RE: Beveled Finger Shims?

Toad:
How many of these connections are there? Assuming 2 bolts per connection. Have a machine shop take a piece of 3/16" x 1.5" x 5' long commerial bar stock and machine it down to almost nothing at one edge, your 5.71° slope. Cut one piece 6" long and punch two slots in it at the proper bolt spacing; then shear two pieces 2" long with punched slots for under the nuts and washers; this makes up the beveled washers for one connection. I don’t think you’ll find anything like that in stock someplace. The machining doesn’t have to be anything fancy, and doing it in 5' lengths before shearing the individual beveled washers shouldn’t cost an arm and a leg.

RE: Beveled Finger Shims?

Why are you bolting to the purlin flange? Purlins are normally connected through the web.

RE: Beveled Finger Shims?

(OP)
dhengr:
I have some sketches on your suggestion out for pricing right now.
I will have to see if they plan to machine large lengths or not...then suggest it.

Hokie-
All I can say is this is not your typical "building" purlin connection.
Hopefully when I get more time I can explain better what this actually is.
But you have me thinking....If we do connect thru the web, I could use a typical cleat angle off the top chord and the purlin wouldn't even have to rest on the top chord angle.

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