- February 7, 2016 at 5:33 pm #87589
Thanks guys, My scrap metal pile is pretty tiny so using what I had I added a piece of tubing from the arch to the pole pocket (similar to Mark’s piggy back arch) and set the evener in front of that. If I can figure out the picture posting thing I will post some on here. Or if someone else wants to post them I can email the pictures. I should be able to test out the cart soon and I will keep you posted on how the geometry works. Like I said before I already have a few things I will change for cart number 2.February 7, 2016 at 6:15 pm #87590
Jared, Not sure how you are putting pictures on your computer (and I am no tech guy!), but one thing you can try is reducing the file size? On my computer I use picasa3. when I want to down load a picture the first thing I do is “export” it to it’s own folder. This makes it easy to find, and give me the choice of what resolution to save it at. I am planning to make another one next winter, too.
I just dropped a couple big trees, so it will get a good test soon, DFebruary 8, 2016 at 7:23 pm #87592JJKParticipant
That makes sense.February 8, 2016 at 9:25 pm #87595Carl RussellModerator
While Donn’s assertion is reasonable, just think about the purpose for thearch. We are trying to lift the weight of the log off the ground. That means we are using the horses to pull a fulcrum over the axle to lift the log. If the evener is set lower than the hitch point, you are basically giving up mechanical advantage. You have just taken ahold of a lever that is shorter than the point of draft.
If your evener is on top of the pole it will pull it down, so if you want to use the pole as ply our fulcrum, you can probably get away with setting your evener on top of the pole, with the hitch point higher, but then we get back to high pole and horses pushing vs lifting.
Dragging weight is different than lifting weight, so even though you could get away wit an evener lower than the hitch point for light work, with heavy logs, and the shorter fulcrum, you will get pole lift. When the pole comes up between the horses they lose maneuverability. One may be able to move the weight, but you won’t be able to direct it very well.
Here is a pic I took today. I still haven’t measured the height yet Jared, but you can see the follow through from evener to hitch, and down to the log.
February 9, 2016 at 7:24 am #87604
- This reply was modified 4 years ago by Carl Russell.
Hi Carl, “Dragging weight is different than lifting weight, so even though you could get away with an evener lower than the hitch point for light work, with heavy logs, and the shorter fulcrum, you will get pole lift.”
Where you say you will get pole lift, I would say it depends. That was the point I was making, don’t put more down pressure on the system than you need. Moving the working chain closer to the spindles is just as effective at reducing pole lift as raising the evener, and they don’t have to be straight across from each other to both be working together.
A drawbar is a very good example of this. Keep a drawbar short and close to the axle or spindles and you can put hundreds of pounds on it with out lifting a tongue. For each few inches longer the drawbar the less weight it can support with out tongue lift.
On the piggyback arch the tongue and evener are set up at the level of the hooks, but because the hooks are back behind the axle there is still the a little tendency for tongue lift sometimes. At least I think that is what Mark said.February 9, 2016 at 9:08 am #87606Mark CowdreyParticipant
Concerning the PiggyBack Arch. You are correct that the pole and evener are set at the level of the log chain hitching points (hooks) in what seems by consensus to be the optimal arrangement. Therefore, as w any arch, when the arch is under way AND pulling (i.e. there is a forward force being applied by the horses in order to overcome the resistance of the friction of the log(s)), the pole is not a significant element in the process and floats along nicely. In the event that the load is pushing the arch, (large load, downhill, slippery going), the geometry of the cantilevered hooks causes the pole to tend to rise. This can be overcome by lengthening the chain between load and arch, creating more drag, until the “pushing” conditions are no longer a factor.
One PBFWA user has described to me how he uses the straight axle and cantilevered hitch hooks to his (and his horses) advantage. He can back up to a log until the axle is against it and by going a little more, the pole comes up and the hooks go down, allowing a shorter hitch, giving more lift when under way.
By the way, I have 6 brand new arches in my barn available or sale. They are currently $590.
MarkFebruary 9, 2016 at 1:53 pm #87612
Mark, I noticed that same advantage with your piggyback. A week or so ago I hitched up to a decent sized pine log with a long chain to pull it out of the slash. Once I got it out I backed the horses up to tighten the hitch and they backed into the log, I was able to pull the slack out of the chain while still sitting and when they stepped forward it was nice and tight. Their harnesses dont fit great so I figured the pole lift would be visible if there was any and it didnt seem to lift at all with the tight hitch.February 9, 2016 at 3:16 pm #87614Mike RockParticipant
Carl, the picture doesn’t show up, at least here.February 10, 2016 at 9:54 am #87621dominiquer60Moderator
The lack of pictures is a problem that we are trying to address with a new tech person and funding that was approved this week. A little patience, and we will see what can be done about this glitch.
February 29, 2016 at 8:53 pm #87912
- This reply was modified 4 years ago by dominiquer60.
Here is a picture my customer took the other day with our first trial run of the new arch.February 29, 2016 at 9:01 pm #87914
It is hard to see in the picture but it has a low platform with a 30inch arch in the back, I had to put the pole pocket lower than planned because the new tires were taller, because of that I put the evener on top and ran a 2×2 tube from the arch to the evener strap similar to mark’s piggyback. As I wrote in don’s post I can easily and quickly step over the arch onto the platform. The Platform is short, putting the handrail close enough to grab from the ground behind the arch. Like I said before I had plans to change the arch before I even got to try it but I was impressed with how well it worked the other day. The log in the picture was 22 feet long hard maple and when the pole would lift shifting my weight onto the platform would balance it out nicely. I hope to get a lot more time in on the arch and I will pick everyones brains at Brad’s workshop on march 12.
Thanks for all of the advice and looking to more in the future.
JaredMarch 1, 2016 at 9:18 am #87916
That looks really good. Simple and stout. DMay 16, 2016 at 8:20 am #88866Michel BoulayParticipantDecember 28, 2018 at 9:20 am #100085Mark CowdreyParticipant
Well I guess this is as good a place as any to let folks know that I am sold out of arches and have no plans to build anymore. Since I first demo’ed a prototype at Ron & Cindy Ames get-together in February (?) of ’07 I made and sold 3 dozen of them. I hope they are out there serving people well.
That last photo is David Fisher drawing out a stick at his place.
- You must be logged in to reply to this topic.