brg
i need to build a portable boring machine, to sleeve two 3 1/2" x 20" pin holes in an excavator which are worn tapered up 5" any help appreciated.
Printable View
brg
i need to build a portable boring machine, to sleeve two 3 1/2" x 20" pin holes in an excavator which are worn tapered up 5" any help appreciated.
Hi brg - welcome to HomemadeTools.net :welcome:
Interesting! I'm going to see if any of our heavy equipment or machining folks have some ideas for you.
Take a look at those portable cylinder boring tools. They are designed to swing a single cutter through the bore. There are also welders to bring the bore back to size so you can remachine them to final size. Attachment 17601Attachment 17602
By the way, there are machine shops that specialize in on-site heavy machinery work.
Use a drill with a magnetic base as a milling machine with suitable supports for a boring bar.
My son has done this for a living and there is not much to it if you want to do it farmer style, you jut make an of set carriers on each side to hold your boring bar made out of a hefty piece of shafting which can use metal to metal close bored holes with plenty of lube.
The drive can be just about anything that can be speed controlled ie: gear mtr with chain and sprocket drive/large drill mtr.
When you finish one side flip boring bar around and repeat. you weld your offsets on to the equipment how ever you can get a good purchase on your equipment.
You will weld your sleeves once you get done with a pin to hold them straight while welding, should not take but a light ream to finish up the holes.
Good luck just remember its not as hard as it looks and keep it simple.
Bill
My machining is rather small scale but - this sounds like a line boring operation. On YouTube CompedgeX described a very similar situation - his channel is here - https://www.youtube.com/channel/UCXi...nuVatgepDzydbw
The relevant video is this one - https://www.youtube.com/watch?v=zQ0489bSE7M
Hope this might give some ideas.
That would be my advice too - in the absence of dedicated equipment like was shown in the video above. Flanged, self-aligning ball bearings bolted to a sacrificial flat steel bar and welded to the cat will work well to hold the DIY boring bar. Good luck and show us the results!
I do not believe the magnetic base drilling machine would be rigid enough. The portable boring machines is the best idea. If you live in a large city you might find a rental place with one.
Hi brg how about a roto-broc drill that’s the one with a big magnet so it will just stick to the side of the machine with a large drill bit or a boring head to clean the hole up for you. Hope that helps all the best ijs61 ( Ian J Smith )
I have built two of these rigs. I used a milwaukee mag drill motor. It had the gear reduction option plus a variable speed VFD control and is rated for a 1.5 inch drill bit. It was very similar to this picture. Which uses the Milwaukee drive motor. I built a very similar rig with two precision shafts and an acme thread drive and a hand driven feed.
http://www.homemadetools.net/forum/c.../2017/04/1.jpg
You will then need a boring bar that will accept the square lath style carbide bits. We cross drilled and tapped ever 3-4 inches. Square holes can be broached or inserts sweated in.
http://www.homemadetools.net/forum/c.../2017/04/1.jpg
You will find that simply sticking a mag drill on will not give the results you want. The vibration will move the drill around and the rack gear has too much play, this will cause bit chatter and quickly destroy both the bit and the work. I also found that connecting the boring bar directly to the motor made it hard to line up and caused vibration. I used a short drive line with two U-joints, this allowed for a slight misalignment while still providing a precise feed.
http://www.homemadetools.net/forum/c.../2017/04/2.jpg
You will also need a couple line up cones to center the bar to the bores while you tack weld the flange face bearing plates on.
http://www.homemadetools.net/forum/c.../2017/04/3.jpg
Also some "L" shaped plates to give a standoff distance between the bearing plates and the pin boss. This lets you see in and should give you enough space to adjust the bit without dismounting everything. Here they used angle iron.
http://www.homemadetools.net/forum/c.../2017/04/4.jpg
The important thing is to have a very precise low back lash feed and a powerful enough motor that you can control the speed of.
There are many ways to build this that will work. The first portable line bore I built, I used a milling table off of a shop drill, to which I mounted the Milwaukee drive motor. It was rigid and fed smoothly without chatter. It was just really heavy to lug around and setup. But as it was a proof of concept, I just used what I had at hand before laying out a lot of money. After I seen it worked, I harvested parts for my next build which turned out much like the one above, only without the shiny paint.
When it came time to press in new bushings, we used a hollow porta power and 1" Grade 8 redi rods. Simply cut plate washers with which to push or pull the bushings into place. This is the exact one we used which can often be rented.
Enerpac Hand Pump Parts - Bing images
Renting a machine, or hiring one might also be a cost effective option rather than building your own. It can be a rather costly thing to build if your only doing a few bores. There are ready to run options out there. Portable Line Boring Machine Tools for Heavy Equipment Bore Repair
The ready made boring bars are worth buying. It's hard to make them cheaper than you can buy them. And the chrome plated shafts last.
I did the welding for Finning's Portable line bore machine about a dozen times before I tried to build one. By then I had a pretty good idea of what was involved and where to source pin material and hardened bushings. Plus he gave me all of the interference fits on the bore sizes. I did the center pins on a dozen loaders and countless pins and bushings on buckets, loader booms and excavators. So it was worth it to me.
I had to do the same job many years ago and we rented a Climax portable boring machine. For a 1 time job I think that would be the easiest solution. Should be able to find one most anywhere as we are in a town of less than 20,000 people and had no problem. Climax has a rental program and here is their contact link We're Here To Help! - Contact Us - CLIMAX Portable
Hi all, you can be inspired by this topic in this interesting french forum!
Aléseuse portative DiY | Usinages
I m also french, so be gentle with my language :)
I think bvd1940 is on the money if you have to bore. Question where are the pins? Most pins run metal to metal, case hardened pin to case hardened bush and usually you can gouge the welds and knock the old bushs out then fit new bushes, weld in with a couple of cones with a through bolt to locate accurately.
Must have been dry for a long time to wear like that.