Backhoe Design Ideas

[charlz]

He does use bushings, but he's also using shims or washers in between the steel parts of articulated joints. He talks about it a little in videos 22 and 23. I know he goes into more detail on one of the other videos, but I can't find it right now. He's got hours of video on building this backhoe of his. When I went back over the videos I realized he was calling them bronze washers rather than brass washers.

At the local D&B they sell a really thin 'machine bushing' which are made of steel. There are some on my backhoe and the three point, I replace as needed. Maybe not as soft as bronze but provide an easily replaceable wear part and likely a lot cheaper.

 

[Iplayfarmer]

I just bought another "hydrolic" component from Ebay. This time it's a cylinder. I think I've decided I'm going to power this backhoe with hydrolics because hydrolic parts are typically about half the price of hydraulic parts.

 

[Iplayfarmer]

Now I'm on to metal questions. I thought I'd asked this earlier, but I don't find it in reviewing the thread: What wall thickness is needed on the 4" X 4" main boom and dipper? My steel supplier has up to 1/4" wall. Do I really need it that thick?

Also, who are some good online or mail order sources for DOM tubing and short cuts? I know it's been discussed before, but please humor my laziness and post a few links or some contact info. My steel supplier says that he can get the DOM tubing, but he has to special order it and it takes a while. In short he didn't seem to excited to supply it.

 

[David Devuono]

Since I did not go back and read the last ten pages of this thread, I will just make the comment that a backhoe with 3000 PSI pump and 3" cylinders will require heavier tubing then one with 2000PSI and 2 inch cylinder. (31,000 lb push vs 6,250 lbs push). I will let you know in a month how my 2300PSI 2 inch cylinder backhoe works with 3x3" 3/16 wall tubing.

 

[Iplayfarmer]

Since I did not go back and read the last ten pages of this thread, I will just make the comment that a backhoe with 3000 PSI pump and 3" cylinders will require heavier tubing then one with 2000PSI and 2 inch cylinder. (31,000 lb push vs 6,250 lbs push). I will let you know in a month how my 2300PSI 2 inch cylinder backhoe works with 3x3" 3/16 wall tubing.

I'm not going to be pushing 3000 PSI for sure. I'll be down in the 2000 PSI range, and I'll be using 2" cylinders. I would also think that the weight of the tractor will be a limiting factor. After you get to the point where the strength of the steel or hydraulics will pick the tractor up and shake it like a small toy, anything more would be overkill. Cost is a factor, but more than that is weight. If I can get by with 3/16 wall tubing that will cut 25% of the weight out of the major components.

 

[Danno1]

Now I'm on to metal questions. I thought I'd asked this earlier, but I don't find it in reviewing the thread: What wall thickness is needed on the 4" X 4" main boom and dipper? My steel supplier has up to 1/4" wall. Do I really need it that thick?

Also, who are some good online or mail order sources for DOM tubing and short cuts? I know it's been discussed before, but please humor my laziness and post a few links or some contact info. My steel supplier says that he can get the DOM tubing, but he has to special order it and it takes a while. In short he didn't seem to excited to supply it.

.

How about:


Discount Steel - The widest selection of steel, aluminum and other metals at discount prices.

Metals Depot? - Buy Small Quantity Metal Online! Steel, Aluminum, Stainless, Brass

Buy Small Quantity Metals Online | Steel, Aluminum, Stainless, and Brass | Allmetalsinc.com

Principal Metals

Metco Supply Inc.


or


McMaster-Carr


.

 

[Iplayfarmer]

.

How about:


Discount Steel - The widest selection of steel, aluminum and other metals at discount prices.

Metals Depot? - Buy Small Quantity Metal Online! Steel, Aluminum, Stainless, Brass

Buy Small Quantity Metals Online | Steel, Aluminum, Stainless, and Brass | Allmetalsinc.com

Principal Metals

Metco Supply Inc.


or


McMaster-Carr


.

Thanks for the links. Have you used any of these? The prices look pretty good, but I wonder if shipping makes up for the better price.

 

[shutt40]

I found it cheaper to buy steel in 10 foot lengths rather than small pieces. If you can design your backhoe to use some common sizes it will really reduce your price. As an example if you price 3 feet of 1/2 by 3 flat bar it works out to around $22 CDN plus shipping from the online guys or $30 from my local supplier, but I can buy 10 feet for $35 locally. Plus he has a scrap pile of small or slightly damaged stuff that you can get by the pound. Online companies would be good for the hard to get stuff.
Frank

 

[Danno1]

.

IPF,

Yes, I have.

McM-Carr is expensive but will ship the same day. Discount Steel will cut exactly what you specify, which is nice. You get a slightly better deal with larger pieces of course.

I do go down to the local scrap yard to save on shipping, but when you need something like AR400 for wear surfaces, well at least you know that you're getting what you ordered.

And yes, there is the shipping...................

.

 

[Iplayfarmer]

.

IPF,

Yes, I have.

McM-Carr is expensive but will ship the same day. Discount Steel will cut exactly what you specify, which is nice. You get a slightly better deal with larger pieces of course.

I do go down to the local scrap yard to save on shipping, but when you need something like AR400 for wear surfaces, well at least you know that you're getting what you ordered.

And yes, there is the shipping...................

.

Thanks for the reply. I know I'm going to have to go mail order for the DOM tubing and for the brass shims. I may just go that route for the whole deal. I'll run some numbers and see what will work best.

There don't seem to be too many opinions about the wall thickness of the 4X4 tubing. I will probably just go with 1/4" to be sure.