Beesource Beekeeping Forums banner

Minimum angle to avoid comb attachment to hive wall

7K views 10 replies 7 participants last post by  Steven Ogborn 
#1 ·
I am thinking of building a top bar hive. What angle (floor to wall) prevents attachment of comb to the sides of the hive? And, while we are at it, what is the maximum practical depth of the hive?
 
#2 ·
I'm not sure that there is any such angle. I have a 60 degree angle, and while there is not a lot of attachment, there is some. That's why a long knife is a basic part of the Top Bar toolbox. The depth depends on the normal temperature, I think. Combs filled with honey are very heavy and will break from the weight. I had one break yesterday, but I caused it by trying to fix some slightly crossed comb. The angle of the walls helps with the weight, but my hive depth is about 9 1/2 inches. I live in a hot area, but I don't like to even touch the bars if the temp is over 90. I have seen recommendations of as little as 7 inches. You live in a pretty warm area so the shallower it is, the less problem you are likely to have with collapses and breaks. The depth of my hives is determined by the angle of the side and floor for a 1x12 board with the angle cut off one side of the 1x12 so it is flat on the bottom. Other hives in our area use 1x10 boards, so they are shallower, of course.

I would strongly recommend finding other KTBH Beeks in your area and finding out what they use. It is very useful to have a standard size so you can share comb and other hive parts.

Ted
 
#3 ·
This is a copy and paste from Sam Comforts web site, with his dimensions for a TBH, bonus is that you can use the top of Lang frames fir bars.....Guess what? I measured one of my top bar hives. Eveything is made from rough cut 1 by 10s. Remember that bees just need a hollow space and dimensions are not important, though this size has proven versatile. To generally keep combs straight on the top bars, they are cut at 1.25” width. This is just the general trend, and NOTHING IS ABSOLUTE WITH BEES.

INTERNAL DIMENSIONS (approximate with rough cut lumber)
Width of top (accommodates a langstroth top bar): 18.25”
Width of bottom: 8.25”
Angle of sides: 120 degrees, gap left at bottom of board makes the side 10.5"
Height: 9”

Top bars: 1.25” by 20” (accommodates 4 popsicle sticks)

A .25” by 20” strip separates the divider boards from the first and last top bars and maintain bee space.
I sit the side boards angled onto the bottom to create bottom entrances. See some pictures. Get creative.

The box is 3 feet long, for convenience. 4 feet would give them even more room.

Born to bee bad,
sam
 
#4 ·
Top Bars:
I use fully Lang. compatible top bars in my KTBH hives, complete with a "bee gap" built into the bars so the bees can get on top of the bars. In my really hot, really humid area (Texas Coast), I use top entrances on these hives & it allows the bees to circulate air over the tops of the bars efficiently, thus aiding them in heat control (VERY important when it's 95F out and 85%+ humidity).

Sides:
The sides of my hive are angled at 60* up from the bottom, as the standard dimension of an equilateral hexagon (i.e. bee cell), this helps dramatically in keeping the sun's rays from hitting the sides directly enough to cause damaging heating, but the bees will make side attachments no matter what you do, short of coating the walls with Slick50 (don't do it...would kill your bees most likley), so just be ready to cut a few attachments every now & then.

Comb Depth:
My hives end up with 9.5" vertical height from the bottoms of the top bars to the top of the bottom board. To date I've only had 1 comb collapse, and that one was 100% my fault; I'd cut the connection of the com for about 1/3 of the total length in order to straighten a curved comb, and the bees didn't get the cut parts reattached before the heat of the day kicked in...:doh:

Lids:
One thing that hasn't been mentioned yet in this thread, but I believe is the #1 most important thing for a KTBH in a hot climate is the lids... For mine, I coat the top of the lid with 2 coats of a high-penetration, white "homestead paint"...followed (after fully dry) by a coat of aluminum roofing paint. The aluminum paint is HIGHLY reflective, and will dramatically reduce the amount of solar heating in your hive. In my opinion, if you don't use the aluminum paint, or some form of metal covering, on your lids, you're not going to be a very happy/successful TBH beekeeper in hot climates.
 
#5 ·
There's no angle that will prevent attachment of the comb to the sides of the hive, but most people
agree on the 60/120 degree angle to minimize comb attachments. Mine are around 64 degrees, because
that's what it came out to when I lined the boards up. My combs end up around 9" deep.
I use 1x12s for the body of my hives, with the sides of my hives set down 3/4" from the top
of the end boards. This matches the thickness of my top bars.
 
#6 ·
Yep, sounds like most people use the 60 degree (or 30 degree from vertical) for the side walls. That's how I built mine, and it works just fine. As stated above, you will always have some attached comb, but it's so random that I can't figure out when/why they decide to attach where they do. I just have a habit of always running my knife down both sides of the comb before even trying to move the bar, just in case there is a bridge that I can't see.

With all the talk of heat and collapsed comb it makes me wonder. What about a TBH that is considered extra wide, to compensate for being shallow. I build mine based on a set of plans that called for a 1x12 sidewall, resulting in 11" comb height. Then I just hacked of 2" to make the combs smaller. But what about making the bars say 24" wide by 8" deep? Has anyone ever tried this? It would give more surface area to attach comb to the bar, and still sufficient volume of comb per bar. I guess the folks that use a half barrel are close to this. I believe those barrels are 22" wide. The downside is that it would not be Lang compatitable, but if you don't intend to run Langs, then what's the worry?

Didn't mean to sidetrack. Back on topic!
 
#7 ·
I think the 22"-24" bars would prob. work...just would be concerned about making them much longer without increasing bar thickness to compensate so the wood doesn't bow/crack when holding up comb full of hone 1'+ from any support.
As far as Lang. compatibility, as long as your box was still deep enough, a Lang frame could simply be attached to the bottom of a 22"-24" top bar & inserted in the hive :D
 
#8 ·
I am curious why you would want less brace comb and not more? If it helps keep comb from collapsing in the hive? Forgive me for asking a ton of questions! I would think the longer bars with a steeper angle would be beneficial. Having less weight (distribution) on the longer bar both in and out of the hive plus the total attached surface area
 
#9 ·
I am curious why you would want less brace comb and not more?
While brace comb may help support the comb while the bees are filling it, it does the opposite, and may tear the comb apart when you pull it out during an inspection. That's why we want to get as little brace comb as possible.


I would think the longer bars with a steeper angle would be beneficial. Having less weight (distribution) on the longer bar both in and out of the hive plus the total attached surface area
Longer bars will help with keeping warm combs from collapsing ASSUMING that the lid is insulated well enough that the higher lid surface area doesn't cause increased heating, and that the bar itself is strong enough (and stiff enough) to support the weight of the comb. Also, the 30 degree angle of a KTBH is arguably the strongest angle for the comb itself, as it runs along a natural division line between cells (IMHO)
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top