View Full Version : New Brentrup F5C in progress

Larry S Sherman
Nov-11-2013, 11:07am
Hans let me know that he is building a new F5C (http://www.acousticguitarforum.com/forums/showthread.php?t=316545) (classic Loar-copy model) for a customer. As a long-time Brentrup evangelist and recent F5C owner I'm very excited to see this new instrument in progress.

Here's a edited version of Hans' build notes, and some of his build pictures:

Just started one of my Loar copy F5C's (http://www.brentrup.com/page8/page8.html), so thought I would finally document one of my builds. This one is a "side bound" 1923 copy and features a red spruce top, flat sawn red maple back, and my violin varnish recipe of spirit varnish over oil. Folks that own my F5C just call it Lloyd.

The blocks screwed to the well worn mold. Rather than use an outside mold for building, I have always used violin style inside molds for my mandolins. Works better in my opinion.

Peghead does echo the Florentine shape, but I think it was more the period than marketing. I really don't think Orville had marketing in mind when he designed them. The pegheads were rather large, and I suspect it was partly the "turn of the centrury" look and partially balance. Just so happens that they balance almost perfectly at the scroll. They might look top heavy, but they are not.

Yesterday I bent and glued the ribs on. I use an electric pipe bender and bend the ribs by hand. I soak the ribs and the pipe is at its hottest before I start bending.

The section of rib is glued with wood glue and clamped. Then I run a bead of cyano over the joints to hold it together while the wood glue dries. Makes it all go a lot faster as you can take the clamps and cauls off within minutes.

Let it sit overnight for the wood glue to dry and will sand inside today. Then it will be ready for kerfing. A bit further yesterday, with the top kerfing installed. The rim was removed from the mold first and some excess on the blocks sanded away. Then the ribs were sanded to 150 grit. At this point, the ribs are ready for the top to be glued on.

I waded through my stash of W.Virginia red spruce found a nice wedge cut in '96. Note that it is split, not sawn.

A small mountain of planer chips and my trusty Starrett carbide resaw blade and we are ready to join the two halves with HHG. Picked out a nice flat sawn red maple back and split it in half.

Every Loar I've ever seen or handled has had a two piece back. I have maple wide enough for one piece, but don't use one piece on Loar copies. So, when I glue up the back, I slip the joint a little. Some Loars had quartered maple with the ////\\\\ flames , but many were more random flame, some narrow, some wide and some very plain. I picked something with medium flame and some randomness to it.

Now the real mountain of chips starts!

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My F5C (http://brentrupmandolinregistry.wordpress.com/2012/03/24/60809-f5-c/) has a clarity and power that I had never previously experienced in a mandolin. My Brentrup M23VB is a bluegrass cannon (loud, strong, resonant bass and cutting treble), but the F5C is simply a different animal altogether. Hard to describe tone, but I think the midrange is dialed in, and the bass and overall frequency range is more balanced. It just sounds like a Loar to me.

I find his approach to the visual details very interesting, especially his selection of tone woods. I think he gets the subtle details correct. I go into a bit more detail (http://www.mandolincafe.com/forum/showthread.php?100146-Brentrup-F5-Comparison-F5C-and-M23VB) regarding the F5C model here.

I can't wait to see how this new F5C (AKA "Lloyd") turns out, and hope to meet the new owner and hear their impressions when it arrives.


goose 2
Nov-11-2013, 11:56am
So good to hear Hans is building again. Maybe he never stopped? I have sadly never played one of his but have always admired his work from all the pictures on the cafe. It will be fun to follow this as it progresses

Larry S Sherman
Nov-11-2013, 12:23pm
Maybe he never stopped?

He did seem to concentrate on guitars (http://www.acousticguitarforum.com/forums/showthread.php?t=312858) for a while. Really happy to see a new F5C being born.


Nov-11-2013, 1:24pm
I actually asked him about mandolins after he started doing just guitars. He seemed adamant that he wasn't going to build any more mandolins. I'm glad to see him building them as well.

Nov-11-2013, 3:13pm
I guess even with the pain in his hands from mandolin plate carving, he couldn't keep mandolin building out of his hands. I'm happy he's making another.


Jim Garber
Nov-11-2013, 7:53pm
I, too, am glad that he is back at it. I hope it is not painful for him and that he keeps up the excellent work. I don't think he ever completely gave up but needed to take a break esp from the super detailed F-models. Looking fwd to hearing more about this one and any others). BTW I also think his guitars are beautiful as well from the ones I have seen.

Jim Garber
Apr-15-2014, 9:58am
Any more updates on Hans' building progress here. I was esp interested in the form he uses.

Larry S Sherman
Apr-15-2014, 11:10am
I'm not sure where he is in the process.

I don't think that he was planning to show any more in-progress because the next phase involved some of his proprietary steps. Hopefully I can get some finshed pics when it is complete, if it isn't already.


Jim Garber
Apr-15-2014, 11:51am
I see there are more pics at that first link you posted on the Acoustic Guitar Forum.

Apr-17-2014, 5:35am
You mean there's an acoustic guitar forum?? Why would anyone devote such time and energy to such an obscure and irrelevant instrument? It probably doesn't get too much traffic as most guitar players can't spell:

"Uh...let's see what to put in the search box...gittar...nope, gee-tar...nope,...gitire...darn internet must be stupid!"