James cowl inlet ring question

I am hopefully getting in the short rows on my cowl work. My inlet rings are a very tight fit in the glass beds. Tight like wacking them pretty hard with the palm of my hand. I plan to loosen them up some. My question is, how tight should they fit? Drop in? Light press fit? As tight as possible? I know this is a feel thing. Will they loosen up when I get some hours on it?
Thanks in advance!

Charles in SC said:

I am hopefully getting in the short rows on my cowl work. My inlet rings are a very tight fit in the glass beds. Tight like wacking them pretty hard with the palm of my hand. I plan to loosen them up some. My question is, how tight should they fit? Drop in? Light press fit? As tight as possible? I know this is a feel thing. Will they loosen up when I get some hours on it?
Thanks in advance!

Click to expand...

Mine started that way and I found that the roundness and diameter were just enough off that they had to be perfectly clocked to fit back. When getting the cowl halves to fit that would not do, so I sanded the bed until the fit tight but not forced into the notch. I used the inlet to mark a 2 x 4 and saber saw to cut a semi circle as a sanding aid and get into that corner. If "we" paint that part it will have to be sanded even more. . . . . before.

A .0015 feeler gage helped find the right area to sand, but do clock them to be sure you aren't chasing it.

Same issue

Charles,
I had the same issue, while building and installing the rings I waxed them and set them in flox for a perfect fit. But perfect was too tight. I never considered Bill's "clocking". But I sanded and sanded and took a dremel tool to it until a "not loose" fit. You do have to be careful when painting that area. You do need a "non restrictive" fit or the two cowl halves will not freely come together.

Clocking? I assumed the rings were turned on a lathe and round, but thinking about it and knowing the rings were dropped on the floor etc. There might be a argument for clocking. But seems like just a little more sanding would allow a fit at any position and allow unfettered installation. I did rotate my rings while working on the fit. Even tried applying adhesive backed sand paper to the ring....but the tightness seemed to be where the male tongue fit in the groove and the paper did not help there, but the dremel did. Keep at it...

Cowl Inlet Rings

For a snug, but acceptable fit, prior to bedding them in flox, cover the ring contact area (carefully & accurately) with thin tape of whatever thickness you want for"clearance". Then proceed normally - when finished remove the "shim" and you should be good to go.

HFS

Thanks for the info. I already discovered the need to "clock" the rings. I have been thinking about "smoking" the rings with something and installing them to see where they are tight before I sand.

Mine were made to a perfect fit, then I quickly discovered after paint I couldn't get the rings in. I sanded till the rings would just drop in all the way and they would easily fall out on there own. Then after paint they are snug. This for me is perfect, when I install the lower cowl I reach up and squeeze the rings in place and they help to hold the front of the cowl in place while I drop the hinge pins in.

I got mine fitting good now but I had not thought about paint thickness. I might need to loosen them a little more.
Thanks