The Framers Forum

I think the old Cassese underpinner I inherited may be on its way out, and I keep thinking about the Hoffman dovetail router and joiner (,https://www.lionpic.co.uk/p/42550/Hoffmann-Frame-Joiner).

it's very expensive.

Does anyone on here have one? I'm just wondering if they're worth the money, or if I should just get another underpinner.

I've owned a second hand MU2 for about five years. I also have an underpinner but use the underpinner less than the MU2.
It really depends what sort of mouldings you use. The Hoffmann makes hardwoods like oak and ash really easy to join, likewise anything with a shape that makes underpinning tricky. The join is also adjustable after inserting the plastic key. The only downside with the Hoffmann is the extra time it takes to join.
Imho the one you linked to (the S-Line or something) may be slightly under powered and at a third of the weight of the MU2 would probably need bolting down as per the holes provided. If you go down this route, I'd keep an eye out for a second hand one on ebay and facebook marketplace and give Hoffmann UK a call to see if they have any trade-ins. They come up for around £1k, but be aware that there are other versions suited to carpentry rather than mitre joining. You'll need to budget for a W0 router bit(c£50), boxes of keys(c£60/box), tall fences(c£250), digital depth guage(c£30).

Hi, pretty much as Justintime says but they are different products and it depends on your business; if you frame in expensive hardwoods a Hoffman would be nice to have. If your core business is framing family photos, posters and artwork in typically flat black pre-finished mouldings then use an underpinner. In an ideal world nice to have both ...

That's great info, thanks both, I mostly seem to be using softwoods at the moment so maybe it's an expense best kept for later. Presumably it's OK to use for softwoods anyway though?

I love my Hoffmann, and use it for more than half of the frames I make. Once you have got the hang of it, the results are fantastic.

BUT

It is significantly slower to make a frame than an underpinner, it creates noise and sawdust, takes time to change the router bit for different sizes, and it is expensive to stock all of the different sizes of keys that you are likely to use.

In the first instance, unless you are using a lot of hardwood, and/or awkward shapes/sizes of mouldings such as deep rebate shadowbox mouldings, I would recommend investing in a decent pneumatic underpinner first.

One note about the various sized keys. I know only buy 18 40 and 60mm W1 keys and 40mm W0 keys. The keys can be cut down to fit after insertion, which saves having to but every single size available.