I bought a broke smithy!

Alcoa, yes that support is the spindle bearing support. It holds the left side, (standing in front of the lathe) of the spindle. It’s really bad engineering if you ask me. The spindle is about 1 foot long and they have the two supporting bearings about 4 inches from each other. On top of that, in order to have the bevel gear for the mill over that bearing support, they needed to thin it up to less than 1/4” thick. Then in the directions to preload the spindle bearings, they tell you to whack the chuck with a big hammer down the bearing line.
 
So the intentions of this repair are to keep the cracked bearing support from flexing towards the chuck as the preload is placed on the spindle bearings. I realize cast iron has very little flex and that is why it cracked here instead of bending but I figured the 1/2” x 3/4” piece of steel might give it a little bit of support against the preload pressures to keep it from cracking in another place and becoming completely unrepairable.
 
Whatever is inexpensive and relatively easy to do is the best approach. Combo machines like the Smithy don't make the best
milling machines so you certainly don't want to put a lot of time or money into a repair
The lathe portion is usually much more useful on combo rigs than the milling portion
Sometime down the line you will probably want to buy a small separate mill and possibly even another lathe
 
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Well, I got off the phone with Smithy. The last time I talked to them, I couldn't believe a small cast part from china was so much and the guy on the phone told me I could talk to the owner. I requested to do so this time around and then was told that the owner said I didn't buy it from them so $1000.00 is doing me a big favor. So I guess moral of the story is, "If you don't buy new, don't expect any support". I kind of thought they would be more helpful in getting me the part for a reasonable price just to keep me interested as a customer down the road. I wasn't looking for a free part, just one with a reasonable mark-up. The whole new machine is only 4995.00.

Well, I think I am going to try to get some money back from the seller and cobble it together best I can and use it until it completely breaks. I can't afford to spend anything more than what I paid for this one and the wife wants to move somewhere warmer in a few years so might not even have a shop after that.

Thanks for all the replies and wisdom everyone.
 
@Flybyjohn
I understand that you are doing the best you can within the investment value you think appropriate.
The 1/2" x 3/4" piece will also act as a tie rod, not just an axial reinforcement, resisting the crack 'widening' under load.
If you can work it out, and have the clearance, would it be possible to also add a steel reinforcement to the top of the bearing mount?
If so, it could be epoxied/match pinned to the casting and screwed to the other steel reinforcement.

Good luck and please reply here with the progress of your project.
 
We used the tapered pins( metal stitching) on engine heads with a good success rate. It might work here. Good thought Gnpenning
 
I looked up the metalocking stitching but couldn’t find the Reid system. It looks like something like that across the top might work but not sure how much space would be required to get a drill jig inside the opening to accurately drill the chain required.

There is only 1/16” or less clearance between the support and the bevel gear for the mill head. I actually think the nylon bevel gear comes really close to touching the support when assembled. So anything over the top won’t work unless sunk in like the stitching.

There is a possibility of drilling and screwing the plate of steel against the support with the screws parallel the spindle ( so through the support and into the steel or through the steel and into the support). I might have to drill some access holes through the headstock that I can plug after the repair is done.
 
fixit said:
In my other life, I supervised repairs on all the air compressors for a large glass manufacturer. I have used this method of repairing castings successfully.

Metalocking Metal Stitching | Metal Stitching Cast Iron

www.metalockengineering.com www.metalockengineering.com

Fixit
Click to expand...
I wonder if something similar could be devised in a home workshop? I have done something similar with wood to hold cracks in place and prevent expansion or lengthening of the crack.
 
Here is my suggestion, referencing the photo looking straight in with the vertical Crack.

The Crack is a rough, male and female matching interface so if properly supported, it should be good.

Start with a STRONG STEEL that will lay flat across the front, covering the Crack, and having it long enough to touch both ends, having it as close a fit as possible.

Locate grade 8 or 10 amall screws, maybe 1/4 or 5/16 size.

You need to have as much of the original intact as possible.

We will use 5/16 for example.

Socket head screws allow stronger screws with small head.

If thick bar is used the heads are easy to countersink by simple drilling, this increases resistance to movement.

Start by predrilling the bar with 2 1/8 holes at each end, not in line with bar but in a column.

Place bar in place and clamp.

Drill hole for tap through both bar and frame.

Drill clearance hole in bar.

Tap and insert screw.

Repeat with opposite end, opposite side.

Finish remaining 2.

Remove and counterbore if needed.

Mark additional pairs of screws spaced an inch or so apart, par attention to where the bearing is at.

Last sets of screws about 1/2 away from the Crack.

Drill all 1/8 inch.

Counterbore all if desired.

Replace back inside and one hole at a time, drill, tap, insert screw.

Torque to spec of screws.

The bar may bend a bit if surface is rough, this is why you do them one at a time.

Make not of order for final assembly.

All of these screws will hold the bar in place.

When all done, fully assemble the unit to be sure everything fits and a screw does to bind something.

Once satisfied it is good, remove it and with a dremmel or other like tool, scar up the cast iron so the epoxy has something to grab.

On the bar hit it with rough sandpaper.

Get some LONG CURE, strong or structural epoxy.

Clean everything with acetone and apply thin epoxy to both parts, rubbing it in to help get it into the scratches, some will get into the screw holes, this is fine.

Place bar and insert the screws.

Tighten all to spec, make sure spindle still works.

Let it cure for a week.

The bar is the structure.

Screws interface the 2 parts.

Epoxy is filler and additional bonding.

Sent from my SM-G781V using Tapatalk
 
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