I have some forced time off work, so i'm catching up on my own projects, today i made a repo of a lower handle mount for Stihl 090G / Lightning gear drive, part # 1109 791 1900.
Stihl 090G parts
- Thread starter scallywag
- Start date
Help Support Arborist Forum:
I have some forced time off work, so i'm catching up on my own projects, today i made a repo of a lower handle mount for Stihl 090G / Lightning gear drive, part # 1109 791 1900.
Will probably outlast the original part by a few centuries !
Relaxing work isn't it.......
Indeed !
mp5n
ArboristSite Operative
Did you do that on a mill-turn?
Sure makes a difference what geometry you do first!!
It was machined on a five axis cnc mill, the original mount was probed and a program made....... load the bar stock and watch!
If anyone needs one of these mounts, just let me know.
And I thought you were an Ol School handle cranker!!!
I'm like you, i like to watch !
From Peter Sellers favorite movie.
I enjoyed CNC work.
But too much the same thing in our plant.
Now I make repair parts. Had a print from 1931 the other day.
And repair parts the CNCs don't get quite right. Lol
On a manual I can use ALL the tolerances to straighten the part.
This is next on the to-do list, we started probing it today and will machine it flat from 200x200x25 mm stock, if it's successful, then i'll fold it where indicated by the red lines.
Why not machine the whole thing?
I already have that size stock x3, if the first one turns out ok, i'll do two more !........ i know it's not perfect, but regardless, it will look better than this!
You were talking about folding ........dangerous without heat.
Dangerous with heat too......
Dangerous with heat too......
The bar cover in the last pic had a tree droped on it.
How's the tree???
The area that i was going to (cold) fold will be machined down to 3mm, the stock is grade 6061, please let me know your thoughts !
It's prolly 6061-t6. Stress relieved with heat. IIRC
It is still very strong.....resistant to bending at that thickness.
It will want to break. Tear apart on the other side of your compression.
I'd try a piece first. With a form die. And it will want to spring back. A good bit. Radius on the inside. Spread the compression.
Another way is to relieve the back with a slot. Thin enough to close on bending. Clamp in form and weld.
But why not machine out of thicker stock?
Silly question. You've thought about that. Lol
It is still very strong.....resistant to bending at that thickness.
It will want to break. Tear apart on the other side of your compression.
I'd try a piece first. With a form die. And it will want to spring back. A good bit. Radius on the inside. Spread the compression.
Another way is to relieve the back with a slot. Thin enough to close on bending. Clamp in form and weld.
But why not machine out of thicker stock?
Silly question. You've thought about that. Lol
Thank you very much!!..... guess what i'm doing tomorrow ?.................ordering thicker stock !
Cheers!
Cheers!
It's cheaper than R&D. Lol
6061 is one of the weaker aluminums most used today. But still very strong compared to the earlier stuff and it welds great.
Used to be there was soft aluminum and softer aluminum.
Great for forming skins in WWII.
Now there is 115,000 lb tensile aluminum. Most welding rod for steel is 60-70,000 lb........
