E: Engine Comet Mongrel

BigEd

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Was the engine in a featherbed at one time ?
When Tony first built the engine it was fitted in a modified Featherbed frame. It was always his intetntion to put it in an Ariel frame, he just needed a suitable Ariel frame and time between other projects to get around to fitting the engine in to it.
 

litnman

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Thanks for that. Is there some reason why you use hole saws instead of an annular cutter? I know the saws are cheaper, but thinking maybe an annular cutter would last longer? I did end up using hole saws instead of end mills because it was faster and less chatter on the poor old Taiwanese vertical mill, but the saws seem to take a beating.
Hole saws in bulk was very economical and worked well in ss and far less expensive than annular cutters. Especially in steep angles such as stair railings deep cut / fine tooth hole saws worked great. For softer materials I had special carbide tipped cutters made.
Interestingly I too have the same small Atlas horizontal mill as yours.
 

Cyborg

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Hole saws in bulk was very economical and worked well in ss and far less expensive than annular cutters. Especially in steep angles such as stair railings deep cut / fine tooth hole saws worked great. For softer materials I had special carbide tipped cutters made.
Interestingly I too have the same small Atlas horizontal mill as yours.

Thanks. When I was dealing with my brother’s estate, I was a little overwhelmed with the contents of his shop and garage. I actually tried to sell the larger mill and considered selling the smaller one. I didn’t try that hard.. when researching the value of the Atlas, it had some pretty good write ups and apparently the one I have turns out to be one of the more desirable models, so decided to just keep it. Seldom gets used though, especially compared to the vertical mill or lathe. The previous photo was just grabbed of the net, this is mine. Currently used to display my chuck collection. The hand wheel on the front unfortunately suffered a bit during its journey across country. Now replaced with one of those alloy idlers that we normally hang on the wall for some strange reason.
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Cyborg

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Proof of concept. New MT2 arbor sitting in there that needs to be threaded for the hole saw. Vise is a little on the large side, but the jaws on the smaller vises aren’t really deep enough. If nothing else, it will cut angles and lengths of tubing that can’t be done in the vertical mill. On a different forum there was a discussion about roller bearings and I mentioned lapping/honing them to size. The dreaded C3 thing. Anyway, the light came on... any reason why I couldn’t convert this mill to also do honing. The subject of speed came up, but I have since had a look at the RPM info plate and it doesn’t appear that speed would be an obstacle. Easy to slow it down more if I wanted to attach a rigid hone and finish cylinders. Any thoughts on the subject? Although the advantages of a Sunnen hone has been explained to me, I still think that with care and frequent pauses to check and measure things that an acceptable result can be obtained.
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Magnetoman

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Any thoughts on the subject?
If you intend on using Sunnen mandrels I'll be interested to see how you solve the problem of applying pressure to the back of the wedge in order to advance it into the part being honed. I never got that far before buying an actual Sunnen hone.
 

Cyborg

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While you had that question rattling around in your head, it was also rattling around in mine. A modified governor from a Brigs and Stratton? Actually I was thinking of asking you what the Sunnen setup looks like, or is it buried in the bowels of the machine? At this point, I honestly have no idea. The rigid hone might work for larger stuff, but I haven’t had a chance to dig it out yet to see if I’m barking up the wrong tree on that one too.

On another note... So can I remain feeling smug, or do you have the device or a reasonable facsimile of the one in the second photo? I’m also feeling juvenile, but can live with that if I can gain some relief from my tool envy.

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Magnetoman

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I was thinking of asking you what the Sunnen setup looks like, or is it buried in the bowels of the machine?
It is buried in the bowels of the machine, but it's a rectangular rod that has a slot in it to engage the back end of the wedge on the mandrel allowing the foot pedal to push the stones up or pull them back down. There's a spring involved as well, whose force is adjusted by the knobs on the front. That is, the slotted rod pushes on the wedge via a spring whose preload is adjusted with those knobs. The absolute position of the slotted rod is determined by another knob. You crank the knob, forcing the stones up, until the dial indicator registers the displacement of something inside the housing. As the part is honed away that displacement decreases.

IOn another note... So can I remain feeling smug, or do you have the device or a reasonable facsimile of the one in the second photo?
I can't tell from the photo what the black shaft at the right end of it looks like. Overall, it looks sort of like a mechanism to make a right turn, e.g. to turn your horizontal mill into a vertical one(?). But, you'll have to let me know what it is for me to tell if I have something equivalent, or if you can sleep like a baby tonight knowing you have something I don't have (but, which I clearly would then need to find...).
 
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