Multiple flat tires on front
The Sunlight tubes I was using have a &quot;ribbed&quot; area near the valve stem. Patches just did not hold in that ribbed area.
Inside the rim no sharp areas or spokes protruding, but I added an additional cloth rim strip and a Continental brand tube purchased from a different shop.
It is holding for now, although this problem sometimes doesn't show up immediately.
Here's hoping it is a good fix.

(later) I am happy to report that changing to a different brand of tube (continental) and adding a second rim strip has solved my problem of multiple flat tires.