Cutting the perimeter of the canopy (7 slider)

[nohoflyer]

It is not clear to me in the instructions hence me posting here.

I am making the initial cuts in my 7 slider canopy.

I see that I’m supposed to remove the plexiglass just above the mold lines.

Besides the “big cut” I don’t see anywhere else on how to trim it. Do I screw it to slider than see where it lies to remove more?

 

[PhatRV]

You trim off the flange from the plexiglass forming process. Then you trim the final shape with the canopy frame as a guide. Do it slowly, sometimes it was 1/8 to 1/4 inch at a time. As you trim the canopy closer to its final shape, the plexiglass becomes easier to fit to the frame. Do you have someone close by who has done this before to help you
The picture below shows the incremental process of trimming the plexiglass to fit the frame in my -8. This is the part to trim the aft portion when the plexiglass is clamped to the frame as a guide.

 

[nohoflyer]

No I don’t have anybody nearby. I’m building in a wood shop in Brooklyn, NY.

Thanks for the reply and the pic.

 

[Ralph Inkster]

Do plexi cutting in a warm room, 70F or warmer.
Use the cut off wheels provided in the kit, try not to warm (melt) up the plexi too much as you cut. Slow & easy does it.
I have used vibrator cut off tools also with great results, again, don’t create hot spots.
Initially cut just the flange off. With trial fitting, you will see where additional material will have to be trimmed to fit right.
Good idea to support the canopy on the table so it doesn’t spread out sideways while trimming.

 

[rapid_ascent]

First off my disclaimer. My canopy is cut and ready to be glued to the canopy frame. I have not completed the installation yet, but I think it is ready. I'll will probably wait until it is a little warmer.

I had the same issue with finding little guidance in the instructions. The main thing is you need to understand how the canopy mounts to the frame. Study the drawing details in DWGs 41 & 43. Some of the trimming depends on how you are planning to mount it to the canopy frame, glue (sikaflex) or screw.

Per the instructions the forward edge is just slightly forward of the canopy bow. Detail B on DWG 43 shows the forward edge position. Section K-K shows the mating with the windshield.

The instructions suggest trimming the lower portion even with the side bows and that is a good first step. For the lower portions you want the bottom edge of the canopy to be positioned relative to the inside canopy skirt (C759) such that it is just above the little flange. I suggest you drill that piece to the canopy bow to set its position. Refer to DWG 43, Section F-F to see how all of the side pieces go together. Once that is in place you can work at trimming a little at a time to get the fit the way you want. If you are screwing the canopy to the frame you will want to have enough edge distance of canopy material so you don't want to cut it too short. Glueing may be more forgiving and there are different approaches used in this area.

For the aft portion it just needs to extend past the aft canopy frame bow. Refer to DWG 43, Section G-G. There is some flexibility in the exact measurement for this cut since the aft shirt is going to cover this portion of the canopy.

 

[PaulvS]

It is not clear to me in the instructions hence me posting here.

I am making the initial cuts in my 7 slider canopy.

I see that I’m supposed to remove the plexiglass just above the mold lines.

Besides the “big cut” I don’t see anywhere else on how to trim it. Do I screw it to slider than see where it lies to remove more?

The plexiglass gets screwed to the frame only later on in the process but earlier on you should use spring clamps (lots of them) to help with positioning while planning some of the cutting. The plexi edge position moves relative to the frame when it gets clamped on.

For the initial trimming of the sides I removed as little as necessary to begin with. I just cut off the stuff that was obviously not going to be part of the final canopy and this was the wavy bits at the edge up to the straight mold lines.

Note that the windscreen portion has much less cut off at the sides than the slider portion. So I actually continued with trimming them separately after the big cut.

The edges of the plexi need to be smoothed after each intermediate cut to reduce the risk of cracking. A belt sander works well for this.

The canopy work cannot be rushed, just take your time.