Bertram33 User Forum

I am contemplating adding a arch for mounting the radome. It is currently mounted on the forward flybridge. My concern is the area on the sides of the bridge where the arch would be installed are not very robust. Has anyone with a arch had any reinforcing done that is more than a backing plate? Any potential pitfalls to avoid? Thanks

Bill, I have one on my B35 that attaches to the horizontal portion of the FB as it curves down. It was on the boat when I got it in 2000, I can lean on it a could probably hang on it (but that's a lot of weight). It has aluminum backing plates to help spread the load. There's a little crazing around where it's attached, but my boat is painted so that may be it. I was going to replace it but opted for a new enclosure instead. As for what to look for, I'd say get one that's all welded as it should be more stable than then ones that are adjustable. The other thing is to consider how it ties into existing ladder and if you want rod holders and so on. Good Luck,

It will be a fully welded arch that will attach to the outside surface of the bridge to clear the enclosure side curtains

Bill, You have a valid concern. The sides of the bridge there are only about 1/8" and the ones I've seen will flex a little if pushed on. I guess if it were me, I'd locate it as close to the base of the flybridge as you can and use decent sized backing plates. Of course you could get really tricky and epoxy some 1/2" marine plywood behind there as big as you can get it....

Try this site. Pre-designed for many different boats. I got my hardtop from them and installed myself. http://www.atlantictowers.com/

Brian, I just bought a Radar Arch in-a-box from Atlantic Towers for my B-35 any tricks to installing it? Thanks, Mike

Mike, Would you mind posting a pic?

Scott, My plan is to tackle the installation the week of the 27th. I'd be happy to post a picture once I get the arch installed. Mike

Mike, I made a simple 2 x 3 frame, 4 corner supports with some diagonals as I recall to get it level and the right height. I presume your side legs have the extra length to allow you to trim to where you want to mount it? Also, I went with plywood backer boards to add to the rigidity of mounting to the sides of the bridge. I had the yard lower it into place with a boom crane, as I was on land at the time. Once I got the side mounts on, I just removed the 2 x 3 frame. Any more questions, just let me know.

Thanks Brian, I plan to use 1/4 aluminum plate as a backer, do you think plywood would be better? Also I thought if I tied 2x4's to my Bimini top for the installation I could slid the arch over the end of them to hold the arch in place while I attached it into position, what do you think? Mike

Mike, I think the aluminum should work fine, just use some tef-gel if using SS bolts. If you've got a yard around that has forklift or crane, you maybe able to work out a deal for use of the equip for an hour or so just have them lift it to the height you need and then you do the install. Post us some pictures when you get done. br,

Hey John great to hear from you, I store my boat in a warehouse over the winter with about 25 other boats so no room for a forklift, I was also thinking I could hang a come-a-long from the rafters if my 2x4 idea does not work. Take care and thanks for your replay, I'll take photos of the installation and post them. Mike

Mike, The 2x4's on the bimini might be OK, but you may find the weight flexing your frame to much or you might find it harder to get it level? Will the spread of the arch be aft of the bridge floor, behind the bridge seats? If the arch is directly above the rear floor I'd do either: - lower the bimini and make a couple of 2x3 support frames in the two back corners of the bridge to hold it up. - or do as you suggested, hang a come-along from the ceiling, that would make is easy to adjust height, though finding a beam directly over your centerpoint may be a little challenging? Regarding the 1/4" Aluminum plate as a backer, I'd be more reluctant to recommend. Depending on where you are mounting, I believe you'll find an ever so slight curviture to that inside bridge wall. I think the plywood is a little more forgiving and will flex slightly better than Aluminum (maybe), but also, as you tighten down on the bolts, the metal will not give and you don't want any spider cracks in the fiberglass around the mount areas. Just my two cents.

Brian, All good suggestions, I thank you very much for your input. I'll be installing the arch in a couple of weeks so I'll let you know how it comes out. Thanks again, Mike

I installed a Atlantic Towers arch on my 33 in 2007. Make sure that the center section is the proper width. I argued with them that it should have been the next size up and they insisted I had the correct one. Long story short...I gave in and listened to them. Once you drill the holes you own it. It works and looks fine, however I wish I stuck to my gut! I had to redo my bimini....Steve