width of end bars

[honigbiene]

I've noticed some discussion of cutting the width of the end bars on the frames down from 1 3/8" to 1 1/4". When that is done, the top part of the end bar is only 1/8" wider than the lower part of the frame (1 1/8"). Why are end bars wider on the top half and then cut narrower on the lower half? Is there some historical basis for this? Is there any reason the width of the end bar shouldn't/couldn't be the same along its whole length?

[BULLSEYE BILL]

A, David, That is meant to be cut from a width of 1 3/8, from top to bottom, to 1 1/4, top to bottom. Not tapered as you read it. [img]redface.gif[/img]

[honigbiene]

I didn't mean tapered. None of the end bars I have seen taper continously from top to bottom, rather the sides of the top half are parallel and 1 3/8" in width, and the sides of the bottom half are parallel and 1 1/8" wide.

This link

http://www.beesource.com/plans/frame.htm

shows my understanding of what the end bar looks like.

It should be easy to cut the end bar from 1 3/8 to 1 1/4 on the wide part of the end bar. That would still leave the lower part at 1 1/8 wide. My question is why are end bars wide on the top half (same width over the whole section) and narrower on the lower half? Why couldn't the end bar be 1 3/8 wide (or cut down to 1 1/4) along its whole length?

[flathead]

My understanding is:

When you shove frames together, the upper portion of the end bars touch and provide spacing.

There is then space between the lower(half) end bars for bees to move from one frame to the other.

Top bars are designed in much the same way so that when frames are shoved together bees can come up from below( between frames) and move around.

Both don't violate bee space rules while providing ventilation and free(er) bee movement.

[middlesattrefarm]

Flathead is right, I have heard of migratory end bars that have a connector on the bottom to preventsway in transport.

[BULLSEYE BILL]

HSC is straight width all the way down. I haven't measured to see what the width is.

[Sundance]

HSC is 15/16" on comb width and 1 13/32" on
the end bars. As Bill says, they are straight
all the way down.

[Michael Bush]

Yes it can be straight all the way down the end bar. They are harder to pry apart, but they also swing less in transport.

[Dave W]

Cutting 1-3/8 side bars to 1-1/4" reduces the bee-space under the shoulders to 1/8". Bees can NOT pass between frames and may fill w/ burr comb.

A more severe problem ??? is the bee space between TOP BARs is also reduced, from 5/16" to 3/16" (.187). An excluder is .163 of an inch [Ref 10, p221]. To correct the space-problem, top bar width must be reduced to 15/16" (from 1-/1/16).

Custom frames can be made to address these problem.

[size="1"][ January 27, 2007, 09:56 AM: Message edited by: Dave W ][/size]

[NW IN Beekeeper]

[Yes it can be straight all the way down the end bar. They are harder to pry apart, but they also swing less in transport.]

Bingo, that is the answer the question was asking for. They are tapered to reduce propolizing so the frames are easier to remove, thus resulting in less damaged equipment. Note some plans don't include rounding the physical thickness of the top taper in alternating corners, this makes them even easier to separate.

IE:

X......O
-------- <-Top Bar
O......X
^Taper

[...the bee space between TOP BARs is also reduced...]
[...top bar width must be reduced to 15/16"...]

Dave points out a very important precaution. Last year I cut my top bars just a 1/16" too wide, 1-1/8", and beespace was tight between frames and nearly non-existant along the hive body walls. The bees will propolize/burr comb this area, but more importantly it becomes unusable space and causes crowding, which in turn can promote swarming.

I have since gone to 1" wide top bars and I use this size because when you notch them for the end bar shoulders/ears you have a deeper and studier grove and fit. End bars are 1-1/4" wide and maintain the standard 3/4" top bar notch [so you can still buy commerical and cut/shave the 1/4"]. When you do the math and fudge the numbers for a little working propolis, it works out right about a healthy 3/8 " beespace.

If you are looking to mod commerically bought frames, I'd say you can tablesaw [for straightness] a skinny 1/8" off each side of the top bars carefully so not to damage the endbar groves. You can plane 1/8" off each outside edge of the endbar, but I don't plane very level so I perfer to saw them also [just watch your fingers because mechanical finger damage takes months, if ever, to heal]. When sawing be sure to use a sharp 40+ tooth blade for a nice finish and better control when pushing through the cut.

-Jeff

[and PS. if you need to move/ship a hive with tapered endbars, push pin thumb tacks in the bottom of the endbars help prevent too much movement]

[Barry Tolson]

Bill,
I'm sure I'll feel foolish for asking, but what is HSC? Thanks.
Barry

[Michael Bush]

> I'm sure I'll feel foolish for asking, but what is HSC?

http://www.bushfarms.com/beesglossary.htm