When I saw the Bachmann Right Angle Hold & Glue Set of clamps it quickly became apparent that I need to purchase a set of these from Micro Mark. These two foam-lined plastic clamps hold structures at right angles while you apply your favorite adhesive. They look like they might be easier to use than the Original Right Clamp, also available from Micro Mark.
Going to order a set and give you my thoughts once I have had a chance to test them out.
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This is from Chooch Enterprises but you can get it from Micro Mark.