forge and/or fabricate mini excavator implement adaptor

[iNOTaRobot]

Hello all,

Well I am faced with a slight quandry. I am not sure whether to NOW forge (with oxy torch and hammer or porta power), or CUT then fabricate up with welding, 2 predrilled pieces of mild steel plate I am using to make a mini excavator implement adaptor.

I will try and explain my need. Hopefully add a few pics. try not to write to long winded explanation.

In summary :- I need to put a 3.5" /90mm accurate stepped offset in 2 pieces of 6"/150mm wide by 18" / 455mm long and 7/16" /12mm thick mild steel plate, while keeping both ends parallel and 6 predrilled/reamed holes inline.




facts

1. I own a 3/4 ton mini excavator, that I need to add a hydraulic auger drill drive to.

2. Measured both excavator attachement points and auger drive mounting pads/points.

3. The excavator boom end is 4" /100mm wide (2 holes per side 1 for boom and 1 for crowd ram)

4. The auger pivot support mounting end pin holes are 11" / 280mm wide ( apart) (1 hole per side)

5. I purchased 2 cut pieces of 6"/150mm wide by 18" /455mm long and 7/16" /12mm thick mild steel plate.

6. Marked out the holes and set both plates on top of other on mill. Drilled the 3 required 1" /25 mm pin holes through both plates. Also added an inner hole part way along plate as an option (DO not plan to use this for auger) One pic shows auger mounted at this point but its only due to an end hole not being reamed fully to take 1" pin during my mock up stage

7. Trialled the drilled plates on excavator with auger. Planned on leaving both side plates staight and just making spaces and longer pins at excavator end.

8. Of course I was adding cross bracing to the 2 plates and some upper lower edge reinforcing

However I felt that leaving both sides plates straight and simply using some 3 1/2" /90mm spacers on the boom end looked like it might be problem.

There is urgency to use the excavator/auger unit to drill 4 holes 13.5" /350mm holes 80" /2m deep in compacted mudstone so as to build a 6ft /2m high retaining wall under my house before rains cause more dirt bank to collapse.

So :-

a. do I mark, clamp to a heavy steel I beam I have. Then heating a plate about the scribed bend mark, bend it using sledge hammer or maybe by my porta power ram and some chain ( feel thats likely to give me more bend angle control.

or

b. mark plate at both bend points. Cut ALMOST through using 6" angle grinder with narrow cuttoff wheel then bend at cut line with heat; before then welding in the V opening the bend will provide to lay fillet weld in.

Be interested in some thoughts please.

probably I would have been better to bend plate first and then drill holes. But I can still drill the single front hole back in a bit from the end as the plate is a little longer than I needed.

Mind you if I do that then I will NOT have enough clearance to let plates hang vertically down with auger vertical.

Wished adaptor to be able to operate either :-

horizontally up under house for maximum head height

or

vertically to make it easy to drill over side of an embankment giving more down reach.

also seasons greeting to all

David
In Australia.

Edited December 20, 2009 by iNOTaRobot

[orgtwister]

if i was makeing this and was going to leave the side plates straight i would get thick wall tubing for the spacers and i would bore the holes so the spacers would go through the side plates and then weld them to the side plates and also weld gusets from the spacers to the side plates for more suport .now if i was making it and hadn't allready drilled holes i would fab the hole thing from pieces so there was no spacers and welded the off set in it like to arms that are flush with the boom to a plate that was wide enough to meet with the wider plates off the auger then guset it for more stregth

[ptree]

I believe that the heavy wall spacers with gussets mentioned above would be my choice at this point. I would bevel every joint and use heavy stick welds.

[peacock]

If you can find some 3.5 inch 3/8 or 1/2 wall square tubing and weld them to the inside of the plates add some gussets, then drill the holes on thru it should be fine. Phil

[forgemaster]

Joggling is the correct term for setting plates such as these, and yes you should have joggled them first then drilled the holes. It will be fairly hard to joggle them and still keep your holes in line, better to do like suggested and use spacers and long pins with gussets. I would suggest using hollow bar as the spacers, try Atlas Steels, Interlloy, or Bohler, they will be in most of the capital cities at least, look in the yellow pages. You will have to bore the hollow bar out some as they are under sized to the FMS
Where are you in Aus bloke.
Phil

[hillsideshortleg]

I am curious, Is your mini a Kobelko and what size is it? I have been wondering how a post hole digger would work on a small mini.
Thanks
Rick

[Dragons lair]

Rick it looks a lot like my 014 kobelco.HMMM a mini with a auger. Might have to look into that and keep the komatsu
05 for digging. Ubracket to the bucket pih, Bucket lines to run the motor. I would weld mine(easier to align) I have a welding shop and have built a Met kit backhoe. Should be fun.
Ken

[hillsideshortleg]

Dragons Lair
I have a 015sr mini. Ya I get made fun of by the hip dudes with the big machines. What is a MET Kit backhoe? We build and install automatic entry gates and the small mini works well for digging small 5' deep holes for our post.