Custom pressure shoes for moulders

A discussion of home-made and custom-ordered pressure shoes for special profiles. August 12, 2001

I'm running a Weinig Profomat 23E with a multiple height pressure shoe. I’ve heard of guys making custom shoes for certain profiles. When are custom-made shoes warranted? How do you make them?

Forum Responses
From contributor M:
I run the same machine for a furniture company. We have a certain crown mould that we make where the profile and the bottom angles cause it to 'rock' when it passes through the last two heads. The flat shoe on the back will not hold it down properly. Since we don't run this profile often enough for a custom hold-down, I bandsawed one out which I clamp to the back of the machine. This cured my problem.

Also, Weinig makes custom nylon pressure shoes.

Considering you are already running a molder with a multi-height pressure shoe, I am sure you are already aware of the need of more than one point of contact on various moldings.

Most shop-made shoes are simple affairs, made to do nothing more than your split shoe assembly (but with less convenience), provide pressure at a couple of points across the timber to stabilize and eliminate chatter.

I will therefore assume you are referring to a counter profile shoe, which is an exact mirror image of the profile. This type of shoe has a couple of advantages over the above.
1. They not only provide even downward pressure but capture the piece laterally as well. This is important if running very short or coped work, where even the slightest amount of snipe would ruin the product.
2. As a counter profile shoe provides even pressure across the entire width of the molding, the undesirable “shine” left by a hard shoe on two narrow points of contact is avoided.

Guin Machinery in LA can provide a reverse profile shoe of nylon that is correctly machined to plug into the stock Weinig bracket. Note: the machining on the top of a standard pressure shoe for a P23e is different than that required on the wide shoe of your multi-height assembly.

You could also grind a set of knives and run a reverse profile on your molder or shaper, or make a mold and cast a shoe. As you can see, a true counter profile shoe, due to the time and/or money invested is probably best reserved for production or repetitive profiles or possibly a particularly challenging run.

I use a lot of custom-made counter profile shoes. There are many sources for these shoes. In the last couple of years, I have been using more impregnated felt. The felt that I use is machineable and can be run through the moulder for exact fit. Use a reverse profiled knife if this is desired.

The use of a split shoe or tilting shoe, when combined with felt, works with a majority of profiles. It should be noted that the felt I use is specially processed to be much more rigid than normal felt. Another advantage to the felt is it does not leave a shine mark that many other types of shoes will leave.

As for custom-machined shoes, any shop that has EDM machines can make this type of shoe.

Dave Rankin, forum technical advisor

I also use felt on two high-speed moulders with very little problems. Just a little contact glue and away you go!

From the original questioner:
Here’s a thought I had the other day when I was up pondering the problem: What if I was to
1) Run a piece of moulding and leave it in the machine.
2) Apply clear packing tape to the face of the moulding to act as a release agent.
3) Make a masking tape “dam” on top of the moulding directly under the shoe.
4) Attach a small piece of plywood to the machine's pressure shoe, bolting it from above into T-nuts in the plywood. I’d have to drill a couple of holes through my steel pressure shoe for this part.
5) Fill the “dam” with bondo and lower the pressure shoe.
6) Commence self back-patting for making my own custom shoe for under 2 bucks.

I’d like to try my idea but won't bother if any of you guys have heard of this method and it yielded disastrous results.

From contributor M:
Since I have been running moulders I have always heard of running reverse profile shoes. I have yet run into a situation where this was necessary. We run a very simple angled pressure plate design. Sometimes it requires a small block of wood to be screwed to the bottom of the plate to keep the plate as level as possible. There only needs to be two contact points. I recommend the two most outer points of the profile. The only problem with the reverse profile shoes is if they don't line up from run to run. What do you do? Make another one. All of these materials expand and contract and warp and they are supposed to line up perfectly from run to run.

We run 85% of our profiles with these plates and they are efficient and less time-consuming. The felt works well but does not take any abuse. If the person who attaches your felt shoe time after time is not the same person feeding your equipment, expect to change this often.

Where can I buy this felt?

There are several different types of felt that are used on moulders. The felt that I use was developed by a member of the Grinderman's Association. He makes the felt available through either the Grinderman's or through MSI. MSI provides the technical instructors for the Grinderman's Association classes.

The impregnated felt is machineable and has a very long life compared to most other types of felt. If a normal felt is used, and this well for short runs, it can be attached to the block with glue or contact cement.

Dave Rankin, forum technical advisor

Guin currently manufactures custom pressure shoes for Weinig. We use a different method than an EDM. Our shoes are made of a durable nylon. Besides being durable, it is also very forgiving. You can cut into the shoe with your cutterhead without damaging the cutterhead itself. This allows you to get as close as possible to the top head.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor A:
I have to say that with modern through feed moulders, the need for special pressure shoes is rare, however I once had to make a counter-profile shoe for running multiples of full-round.