The Shop > Our Shop
Simple DIY toe jack plan?
PekkaNF:
Last week was busy, but made a sketch of traditional hydraulic toe jack. Bought cheap 2t bottle jack and checked it. I could not trust it to support any load near my fingers - clogs, wedges and timber.
Therefore "Plan B": Screw jack type.
First scissor jack I checked seemed to have nice thread but plastic nut...don't get me wrong, I think that plastic can be used an lot of stuff but I would not buy cheap lift and use it, sooooooooo I looked up on table of the metric screws and whilst M10 seems to be a little marginal to lift one end of the 1t machine, M12 seemed to have enough security. Some more doodling and quick visit to local nut n' bolt shop produced 180 mm thread length M12 bolts with 19 mm AF hex. I wanted to have normal hex head - easier to use standard ratchet wrench and avoid using bar, etc.
Hard look on the corner of my dungeon and with a bit digging I found 50 mm C-channel, 40*100 mm L-section, flat bar and round bar. All hot rolled and least somewhat weldable. Hardest part was to decide how to mount the screw to minimize side load - all tables assume that the bolt/nut is mostly in pure tension (no bending). Decided to use classic round dowel nut/pivot design. Now this 180 mm length does not look too long anymore....on my disposable all welded structure there were no problems to reach effective 100 mm lifting height for dolly, but half way I got this idea of making it more professional and easier to repair and I'm watching my daylight disapearing. Also I found that one 25 mm bar that has carbon inclusions and eats my drills....now I have to paint/mark it to be used only where crappier iron will do.
Got to the point where I'm having most parts ready.
pekka
PekkaNF:
Just got home - and it is about to hit the hay or tomorow will be even more proverbial....
Here is a consideration: How well stick weld will hold hot rolled parts together: I need to weld the bushing into "toe" to allow a degree of movement for the barrel nut. Longer the weld, stroger it will be, but at the expence of the lifting height.
The part is now near 30 mm long, two beads, both sides? If I could cut it 20 mm long it probably would allow just enough height.
Or I could buy 8.8 grade all thread and weld long nut to it if it really comes to that. But I like standard parts.
Pekka
PekkaNF:
Bit more progress. One hour goes fast.
There is some extra material on column. One retainer and some minor features left, but at 100 mm lifting length is a bit marginal.
Pekka
RobWilson:
Following along with interest Pekka :thumbup:
Rob
PekkaNF:
That swivel bolt is bit overkill, but haven't been able to locate (locally) DIN 6319 Spherical washers, those would give a bit more headroom and allow enough of flex, play and inaccuracy:
https://www.ganter-griff.de/en/products/3.2-Mounting-positioning-leveling-via-clamping-bolting-and-supporting-parts/DIN-6319-Spherical-washers-Steel
DIN 6319 CD pair to bottom end and DIN 6319 D/G washer and DIN 6330 nut on the top end?
I'm sketching/piling up crap stock metals for dolly, have to build them too and it would be nice if these were compatible. Although not too bad to lift a bit with tiny toe jack, put stabilizing 2*4" onder the machine, lift other end and continue with bigger toe jacks (that I can borrow, but those are big/heavy and 30 km away - not handy for every and each move and maintenance).
Small tools and baby steps, all under 2t.
Pekka
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version